BU-804b: Sulfation and How to Prevent it

Applying ways to minimize sulfation.

Sulfation occurs when a lead acid battery is deprived of a full charge. This is common with starter batteries in cars driven in the city with load-hungry accessories. A motor in idle or at low speed cannot charge the battery sufficiently.

Electric wheelchairs have a similar problem in that the users might not charge the battery long enough. An 8-hour charge during the night when the chair is not being used is not enough. Lead acid must periodically be charged 14–16 hours to attain full saturation. This may be the reason why wheelchair batteries last only 2 years, whereas golf cars with the identical battery deliver twice the service life. Long leisure time allows golf car batteries to get a full charge overnight. (See 403: Charging Lead Acid.)

Solar cells and wind turbines do not always provide sufficient charge for lead acid banks, which can lead to sulfation. This happens in remote parts of the world where villagers draw generous amounts of electricity with insufficient renewable resources to charge the batteries. The result is a short battery life. Only a periodic fully saturated charge can solve the problem. But without an electrical grid at their disposal, this is almost impossible.

An alternative solution is using lithium-ion, a battery that prefers a partial charge to a full charge. However, Li-ion is more than double the cost of lead acid. Although more expensive, the cycle count is said to be cheaper than that of lead acid because of the extended service life.

What is sulfation? During use, small sulfate crystals form, but these are normal and are not harmful. During prolonged charge deprivation, however, the amorphous lead sulfate converts to a stable crystalline and deposits on the negative plates. This leads to the development of large crystals that reduce the battery’s active material, which is responsible for the performance.

There are two types of sulfation: reversible (or soft sulfation), and permanent (or hard sulfation). If a battery is serviced early, reversible sulfation can often be corrected by applying an overcharge to an already fully charged battery in the form of a regulated current of about 200mA. The battery terminal voltage is allowed to rise to between 2.50 and 2.66V/cell (15 and 16V on a 12V mono block) for about 24 hours. Increasing the battery temperature to 50–60°C (122–140°F) during the corrective service further helps in dissolving the crystals.

Permanent sulfation sets in when the battery has been in a low state-of-charge for weeks or months. At this stage, no form of restoration seems possible; however, the recovery yield is not fully understood. To everyone’s amazement, new lead acid batteries can often be fully restored after dwelling in a low-voltage condition for many weeks. Other factors may play a role.

A subtle indication whether lead acid can be recovered or not is visible on the voltage discharge curve. If a fully charged battery retains a stable voltage profile on discharge, chances of reactivation are better than if the voltage drops rapidly with load.

Several companies offer anti-sulfation devices that apply pulses to the battery terminals to prevent and reverse sulfation. Such technologies will lower the sulfation on a healthy battery, but they cannot effectively reverse the condition once present. It’s a “one size fits all” approach and the method is unscientific.

Applying random pulses or blindly inducing an overcharge can harm the battery by promoting grid corrosion. There are no simple methods to measure sulfation, nor are commercial chargers available that apply a calculated overcharge to dissolve the crystals. As with medicine, the most effective remedy is to apply a corrective service for the time needed and not longer.

While anti-sulfation devices can reverse the condition, some battery manufacturers do not recommend the treatment as it tends to create soft shorts that may increase self-discharge. Furthermore, the pulses contain ripple voltage that causes some heating of the battery. Battery manufacturers specify the allowable ripple when charging lead acid batteries.

Last updated 2016-09-22

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Comments (662)

On March 8, 2012 at 3:06pm
Odd Styrmo wrote:

On the market I have been offered a gadget named Megapulse (www.megapulse.net) . Australian made and supposed to reduce/remove sulfation.
Do you know anything of these ?

On March 9, 2012 at 6:21am
Carl wrote:

In a sulfated battery, which is so heavily sulfated, beyond desulfation, is it possible
to drain the electrolyte and using a rotary tool, cut the battery top off and lift the battery out of the housing and clean the plates, reinstall the battery, replace the electrolyte, reseal and charge it? Is this possible? I have one that was used in my PV system in which I was forced to replaced.

On April 5, 2012 at 1:28am
John Fetter wrote:

Odd Styrmo - Megapulse makes and markets pulse desulfators. While they claim their pulse units can desulfate batteries, they are unable to explain how this is achieved - which is not surprising because pulsing does not desulfate. However, their units seem to be able to keep batteries from dying prematurely, so obviously something beneficial is happening. I tried to discuss this aspect with them but they weren’t interested.

Carl - It is obviously possible but is it worth doing? I think if you approach the task with an open mind, you will become more observant and less likely to see things that aren’t really there. Assuming you are dealing with a 12V car battery: Personally I would put the battery on a slow charge for a week. This can be done with an ordinary car battery charger, plus a light bulb connected in series with the mains input. Select 25, 40, 60 watt for very low, low and moderate current. Then you test the battery. If it has not improved, do as you suggest - open it up, clean the elements and reassemble. Then, at the end of the experiment you will know for certain whether, or not, it is possible to recover a sulfated battery.

On April 8, 2012 at 9:06am
Chris C. wrote:

Odd Styrmo: I am always suspicious of companies that hide their ‘secrets’ with marketing BS. If there was anything there, they wouldn’t be afraid to publish the basis for their claims and have a patent for it.There are more reputable companies out there that don’t hide their ‘secret’ and tell you, just like the author here, that the benefits exist, but are limited.

Carl: cutting off the top is possible, batteries used to be glued together with a tar-like sealant, but it’s a dangerous job if there is any remaining charge on those plates should you cause a short while cutting. If you’re adventurous you could use a booster cable and connect the free ends well away from the battery, in open air, to see if it will spark wink .

Have you tried emptying the cells from the top and rinsing them first? This can remove the mud that accumulates at the bottom and can be a cause for sulphation inducing shorts. It will not remove chunks of lead, though. For that you could try drilling a hole in the bottom and flushing the cell from the top, this could remove fairly large sized chunks. Apparently, hot glue makes an effective plug, but I doubt it has sufficient mechanical strength to seal the battery top to the case, like you are planning to do.

On April 8, 2012 at 11:48am
Carl wrote:

John, Chris,
I had a couple of deep cycle batteries that were sulfated heavily. I had a thought about cutting the top completely off and cleaning the plates. However, you are correct concerning charge remaining on the plates. I decided a few weeks ago not to take that route. Instead, I replaced them. I had a third battery suffering minor sulfation. This battery would not hold a complete charge. It would only charge to 90%. With a 1A load the battery discharged rapidly within minutes. This is a 90 AH battery. Therefore, I purchased an XTREME CHARGE DESULFATOR 12V. www.xtremecharge.com and Within 3 weeks of of continuous pulsing and charging, that battery was back to full capacity. I did not connect this unit to the heavily sulfated batteries, because I did not have the XTREME CHARGE DESULFATOR at that time. If I did have this unit at the time I found the other two batteries heavily sulfated, Naturally I would have connected it to those. Well, as the saying goes, can`t win them all.

On April 8, 2012 at 6:04pm
John Fetter wrote:

Carl - How did you determine the batteries were sulfated? Chemical analysis? Had a look inside, saw some whitish stuff and made an assumption? It seems the the battery was not functioning properly and you assumed it was sulfated. Your description of the battery that did not do well with a 1A discharge and then responded to 3 weeks of pulsing is typical of another type of defect. Did you know that there has never been a satisfactory explanation on how pulsing is supposed to desulfate a battery?

Lead-acid batteries have been in use for well over a century. It was only in 1991 that the first pulse “desulfator” was patented. No one can tell me that not one inventor ever thought of pulsing a battery before 1991. Of course they tried. Over and over and nothing happened. Something happened inside the batteries in the 1980s. Batteries became low maintenance and maintenance free. How was that achieved? The manufacturers changed the alloy composition of the battery grids. The new alloy that they used is the cause of the problem that pulsing seems to be able to treat.

The original alloy was lead-antimony. The new alloy is lead-calcium. An ultra thin oxide layer forms between the positive grid and the positive active material. Eventually the battery does not accept charge, does not deliver amps. Battery manufacturers have a few names for this condition: (1) “open circuit” and (2) “antimony-free effect”. Pulsing breaks down this oxide layer.

On April 9, 2012 at 7:03am
Chris C. wrote:


This is the first I’ve read on this issue - pulsing breaking down an ‘oxide layer’ between the positive grid and the positive grid material. As we all know, the positive material IS made of lead oxide(s). What type of oxide are you talking about between that and the positive grid itself, that would interfere to that extent with battery capacity?

I understand that lead acid chemistry is complex and not fully understood, and there is little hard evidence (at least online) to directly relate desulfation to pulse conditioning; but I have not found significant evidence that pulse conditioning does not increase battery capacity and reserve as measured in the conventional manner, by load testing and electrolyte concentration measurement.

So, if not sulfation, what phenomenon are you talking about that pulse conditioning seems to cure and could you supply some references?

On April 9, 2012 at 1:58pm
John Fetter wrote:

Chris C. - Lead-acid chemistry is most definitely well understood. There is plenty of excellent literature, Handbook of Batteries by David Linden; Lead-Acid Batteries by Hans Bode; Electrochemical Power Sources by Monty Barak and, of course, Storage Batteries by George Wood Vinal and so on.

There is an abundance of information on so-called pulse desulfation at the United States Patent & Trademark Office, uspto.gov/patents/process/search. Use their boolean search facility. Start with “lead acid” in field 1 and run through “sulfate”, “sulfation”, “pulse”, “pulsing”, etc. in field 2. A picture soon emerges. The patents are all written by inventors who describe their own version as correct and all previous versions as flawed. You will find at least 70 patents if you look long enough. There is not one explanation that holds water.

Lead-acid battery manufacturers are fully aware of the problems with low maintenance and maintenance free batteries. They all make the same type and therefore the consumer cannot avoid the problems. Two out of every three batteries sold are replacement batteries. The industry relies for its very existence on the replacement market. A bright young engineer in a battery factory would be ill advised to go to his boss with a new idea on how to make batteries that last longer. Not a career enhancing thing to do.

Pulsing must provide at least some benefit, otherwise there would not be thousands of desulfation pulse merchants making a living around the world.

The positive active material is lead-dioxide. Lead-dioxide is a semi-conducting material. When it is housed in a lead-antimony grid, the antimony and dioxide remain firmly in contact. When housed in a lead-calcium grid, an ultra thin oxide layer of a different kind builds up over time between the grid metal and the lead-dioxide, which takes just long enough for the battery to survive a couple of years. Manufacturers add a little tin to try and prevent this problem but it is not very effective.

The term sulfation is overused. No one bothers to check whether it actually describes what has really happened inside the battery. Most of the people who work on pulse equipment are electronics oriented. Do not really understand batteries very well. They assume the other guy knows what he is talking about. It is not unusual to have millions of people convinced they know what is going on and then one day to discover they were all wrong.

I am a lone voice in the wilderness. I am perfectly content to be so.

On April 9, 2012 at 10:33pm
Chris C. wrote:

Thank you for your thorough response, John. I can’t help but wonder what your area of expertise is, because you seem to know a lot and have apparently done extensive research on the subject.

Although I tend to dismiss conspiracy theories when it comes to engineering advancements, when you stop and really think about it, is does make sense: by making a product ‘maintenance free’ you also make it ‘maintenance proof’. By taking away the human factor responsible for a lot of errors leading to failure, you also end up with a product that cannot be maintained effectively.

When I studied lead acid battery chemistry in junior college 40 years ago, my chemistry professor said the lead acid battery chemistry was actually much more complex that the usual simplification that was used to describe the reaction, that it wasn’t fully understood and that the actual process likely included many intermediate lead oxide and lead/sulfur compounds. So I’m looking forward to read up more on the titles you mentioned smile

On April 10, 2012 at 2:03am
John Fetter wrote:

Chris C. - My background is industrial electronics, power converters, some of the equipment quite large. Thirty years ago I decided I could design and build an electric car. I teamed up with a large automobile manufacturer and a large battery manufacturer. The car was great, the commercial prospects dismal. The marketing director of the battery manufacturer made a suggestion. If I can put together the resources to build an electric car, I can do even better designing and manufacturing certain auxiliary products for batteries for his company. The commercial prospects looked good, so I went ahead

One learns a great deal more working alongside, not inside an industry. People are inclined to discuss things differently. One day someone suggested instead of purifying battery refill water, it might be a good idea to find a way of putting something into the water to make it suitable for refilling. I decided it was worth a try. Made a few preparations and tried them out on some golf-cart batteries. One of them had an unexpected effect. It reduced water consumption.

Decided to commission an independent laboratory to run carefully controlled tests. Their testing showed the same reduction in water consumption. They carried on testing until all the had batteries had worn out. The batteries that had been fed the treated water lasted between 40 and 60% longer. The water treatment not only worked, it had done so beyond all expectations.

I have been unable to find one battery manufacturer prepared to discuss this discovery coherently. 

Decided to study the deepest inner workings of lead-acid batteries in some serious detail to find out what it was that the treatment was doing right. In the process also worked out how pulsing worked.

It seems I found a gold mine in the main street of town - but everyone just keeps walking past it, refusing point blank to look.

On April 11, 2012 at 10:10pm
Andrew M wrote:

John, what was it that you introduced to the battery that reduced the water consumption?

Also, on the subject of desulfation and reducing water loss what is your view on chemical products like China depot, probat,  and resurex? 

There has to be someone willing to spread the info needed to further understand the pulse technology and why/how it works. The way I understand it… and help clear it up if I am wrong… by pulsing at the correct frequency or a variety of frequency this would help shed sulfation. Because the crystal sulfate grows on the plate during discharge as small to large crystals and we know everything has a resonant frequency, by using a specific frequency or a variety of frequency that would induce that crystal to vibrate and break down or atleast help shed from the plate.  Correct? Or way off?

On April 12, 2012 at 12:28am
John Fetter wrote:

Andrew M - It took years to develop and to test the material that can reduce water consumption and extend battery life. The testing alone cost $80 thousand. When one extends the service life of a $3500 motive power battery by 40%, it translates into a $1400 saving. In 2010 there were $11 billion worth of motive power batteries in use worldwide. I think you will agree there is no useful advantage to be gained by shouting out its identity.
It does not appear to serve any purpose to discuss individual “desulfators”. Most of the concepts rely on belief, rather than technical merit. Hundreds of billions of dollars worth of merchandise are sold annually worldwide purely on the basis the purchaser believes there is a benefit.
3.26 MHz resonant sulfur frequency desulfation makes no sense to me. It is impossible to maintain this frequency on the required resonance among thousands of batteries by discharging an inductor into a battery. Circuit capacitance is not fixed. Resonance in an oscillating circuit depends on L and C.
If the pulsing looks like a damped sine wave, the energy is NOT going into the battery but is being dissipated by the resistance of the circuit. Energy can only be transferred into the battery by fully damped, single pulses.
If the battery treatment causes material that is allegedly sulfate to be shed from the plates, then this amounts to ampere-hours being cast off permanently. 

On April 21, 2012 at 3:13pm
Joe Clack wrote:

I hear that some times about an ounce of Acetic acid (white Viniger) added to each cel of a 12 Volt Battery can “De-sulfate a battery…..Is there any truth in this??


On April 21, 2012 at 3:43pm
John Fetter wrote:

Joe Clack - I doubt whether the acetic will desulfate a battery but I suspect it might help to recover a battery that is suffering from an ultra thin oxide layer between the surfaces of the positive grids and the lead dioxide active material. This is known in the battery trade as “open circuit” or the “antimony-free effect”. It is quite common. Modern SLI batteries have lead-calcium alloy grids. Older batteries have lead-antimony.
When the calcium type of battery is operated too long at low charge, an insulating oxide layer develops at the lead-calcium and lead-dioxide boundary. The acetic dissolves some of the lead at the surfaces of the grids and also the boundary oxide, helping to reestablish contact. Fortunately, only a small amount of lead will be dissolved before the acetic is eliminated. Lead-antimony batteries do not suffer from this problem. Their particular disadvantage is high water consumption.
Why not try it in the interest of science?

On May 1, 2012 at 1:06pm
Mike Rosera wrote:

I also would like to know what you can add to a battery - I think there is a useful advantage to share with some of those who wish to know (send it to mrosera@new.rr.com) - I’d like to experiment with my deep cell. Thanks!

On May 1, 2012 at 4:45pm
John Fetter wrote:

Mike - There have been hundreds of battery preparations and electronic aids. Advertised according to the “AIDA” principle; sold at modest prices. No one has ever succeeded in this line of business beyond the cottage industry level. Giving away the formula sounds even less attractive.

On May 4, 2012 at 1:43am
Malcolm wrote:

Somewhere I heard that a pinch of Magnesium sulphate will help rejuvenate a sick battery it seems to work however I haven’t done any in depth scientific tests.

On May 4, 2012 at 4:50am
John Fetter wrote:

Malcolm - People have been proposing and using sulfates of many metals. The most common being aluminum, potassium, sodium and magnesium. There have been scientific tests done by the US National Bureau of Standards under George Wood Vinal more that half a century ago. The Institute proved every single battery remedy containing these metals had no meaningful effect. Their findings caused an uproar. MIT got involved. There was legal action. The US Congress got involved. In the end, the Institute’s findings prevailed.

What they definitely did help to demonstrate is that people who promote these battery preparations will go to almost any lengths to stay in business.


On May 13, 2012 at 7:03am
Ofer R wrote:

Andrew M. - In regard to your remark about the resonant frequency of sulfate crystals, I gather you were referring to mechanical resonance and if so I would suggest enacting mechanical pulses such as sound or ultrasound waves rather than electric pulses. The water based medium inside the cell is perfect for conducting these waves.
I see no logic in trying to breakdown a mechanical structure with an oscillating voltage, which probably affects the cell at the chemical level.

On May 13, 2012 at 9:11am
John Fetter wrote:

Ofer R - Are you suggesting that sending high frequency sound waves into the battery eliminates sulfation? If so, it would be very instructive if you can explain how this works. There are billions of dollars worth of batteries being scrapped world-wide every month because of sulfation.

On May 13, 2012 at 1:19pm
Ofer R wrote:

John Fetter - I apologize if my post was misleading. I do not claim to know how to breakdown sulfate crystals with sonic waves. I do know quite a bit of physics and have experience in R&D of certain devices. I was merely pointing out that the notion of pulsing voltage spikes on the battery terminals at the crystals resonant frequency has very little to do with mechanical damage done to them.
I think the battery companies go to great lengths in order to limit the life of lead-acid batteries. This is not a conspiracy, it’s just business. The only green that motivates industry is money (sadly), everything is designed for a certain amount of cycles.
You however seem quite knowledgeable in this field, I doubt you need my help. If you wish to share ideas though, I’ll be more than happy.

On May 13, 2012 at 5:31pm
John Fetter wrote:

Ofer R - I thought perhaps you knew how sonic achieved desulfation.
My theory is that it is predominantly self discharge that causes batteries to sulfate. One can attempt to overcome sulfation and gain commercial reward by selling product that addresses the end of the process; or go to the front and reduce self discharge to as near zero as possible. (There is more to sulfation but one has to start somewhere.)
Batteries are sold nowadays purely on price. Batteries are a grudge buy. Manufacturing batteries has become a very low margin industrial activity. Comparing the size of battery manufacturers with the size of their customers, the ratio is often one to one hundred. I think battery manufacturers have, at best, only limited influence.
This would seem to imply that outsiders can be reasonably assured of unimpeded progress if they are determined to improve battery life. However, I do not believe this can be achieved by tinkering with over-the-counter consumer products.

On May 19, 2012 at 9:50am
David A. Mead wrote:

The very essence of the chemical interaction that produces electricity produces lead sulphate. When fully charged all the sulfuric acid molecules are bonded to water molecules (H2) to create battery acid or electrolyte (H2SO4). When a battery delivers an electrical current the sulfuric acid molecules break their bonds with the water and combine with the lead dioxide (PbO2) in the plates creating a new chemical compound known as lead sulphate. Therefore, whether a battery discharges through use or self discharge sulfate is always created. The damage comes when the lead sulphate compound is not reversed by recharging relatively soon.

I have taken batteries over 5 years old that only delivered 30 minutes of discharge “run time”. By recharging them and applying a pulse technology desulphator I increased the run time to 34 minutes, 44 minutes, 49 minutes and so far just over 55 minutes. My conclusion is that as the sulphation is removed form the lead plates there is now more capacity to re accept the molecular exchange that produces an electric current this evidenced by the significantly increased run time. I use the BatteryMINDer battery maintainer desulphator for over 13 years always with good results.

On May 20, 2012 at 12:03am
John Fetter wrote:

David - There is a desire to attribute healing properties to desulfation products in all of us.
However, the description you have provided is a good fit what happens when one uses a pulse charger or a plain charger. Repeated charging, discharging acts progressively on the lead sulfate crystals in the negative plates, helping to convert more and more into lead metal crystals plus sulfuric battery acid, at the end of each successive charge. (Positive plates do not suffer from permanent sulfation.)

On June 3, 2012 at 1:51am
Vic wrote:

I am about to install 6x8 volt trojan deep cycle batteries in my golf cart.I get approx 525 rounds, 4.5years live out of these batteries. HYow can I get an improved life from the new batteries I am installing.I recharge immediately after every round and maintain the batteries properly.

On June 3, 2012 at 4:12am
Oscar Ormond wrote:

I have been told you can get 50% Xtra cycling if you use the stuff described on batteryvitamin.net

On June 3, 2012 at 9:48am
tampajym wrote:

I have been told you can get 50% Xtra cycling if you use the stuff described on batteryvitamin.net

It would seem after a brief review of the aforementioned site that this substance is similar to that invented by John Fetter.  Am I in error, John?

On June 18, 2012 at 9:12am
zed wrote:

“I understand that lead acid chemistry is complex and not fully understood,”

Are you kidding me? You can’t be serious.

This isn’t nuclear physics. It’s simple elemental chemistry. Because of that one idiotic statement this entire website becomes dubious at best and dangerous at worst. It matters not who wrote that rubbish, owner or guest, but allowing that statement to stand is what matters.

I urge everyone to take everything here with a grain of salt.

On June 18, 2012 at 1:54pm
Oscar Ormond wrote:

@ zed

Get off your soapbox. U can buy reading glasses real cheap at any pharmacy/drugstore.

On June 18, 2012 at 4:32pm
tampajym wrote:

@vic, where are you located.  I may be able to help you.

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On September 1, 2012 at 5:31pm
King wrote:

Add some graphene into the battery.  Would it help ?

On September 7, 2012 at 4:19am
John Fetter wrote:

King - Great idea. Graphene is the ultimate high performance carbon. I suspect you’ll need to add something to keep the graphene in suspension. It is unlikely to cause any problems. Hopefully fix lead-acid problems such as sulfation. Is it cost effective?

On September 8, 2012 at 10:15pm
Terry t wrote:

I remember that you used to be able to buy a recondition battery when i was younger (30 years ago ) i was told that they applied a high reverse charge on the battery then then drained the power then recharged it the proper way anyone ever herd of this before? Nobody ever really finished answering the question about splitting the battery open then cleaning the plates ,would this work or not ?

On September 8, 2012 at 11:36pm
John Fetter wrote:

Terry t - You can buy reconditioned batteries today for about $29.95 to $39.95. Reconditioners take in scrap batteries, work on them, about 30% respond and these receive a new label and are sold . People used to want to buy good stuff. Nowadays they want to buy cheap. Caveat emptor.
There are plenty of old wives tales about reconditioning batteries. There are enough people who, deep down, believe anything when the story is well told.
Splitting a battery open to clean it out is a natural inclination - the inside of an old battery looks messy, so why not clean it out? Does it work? Use you imagination.

On September 22, 2012 at 3:11pm
Oscar Darwin wrote:

I live in a very hot climate where battery life is often measured in months rather than years. My assumption is that short battery life here is largely the result of the extreme ambient temperatures combined with poor maintenance and the poor quality of water being added to the batteries. I’ve begun using one of the more well-know powdered chemical additives for de-sulfation. (the name was mentioned briefly in another post) Regardless of what has been said here regarding these products…it’s hard to argue with success. I’ve been taking large industrial batteries that were discarded as scrap…and subsequently doubling the life of many of these batteries. I’ve also discovered that I can greatly extend the life of batteries if this product is added BEFORE it begins to reach it’s end-stages of life. I also discovered some old military documents from the 1950’s that document a mixture of chemicals used to dissolve sulfation in aircraft starter batteries. So if the US military was doing it back in the 50’s…I don’t understand why you say it can’t be done today…and even improved upon????  As I said…it’s hard to argue with success. I plan to continue using this particular product!!

On September 22, 2012 at 8:52pm
Chris C. wrote:

Are you a troll or are you just looking to scam people with some mystery snake oil? All that hush-hush about your so-called ‘product’ and the obscure military papers you ‘discovered’ sounds very suspicious to me…

On September 22, 2012 at 10:56pm
John Fetter wrote:

Chris C.- I agree with you. “it’s hard to argue with success.” “I plan to continue using this particular product!!” Obviously a salesman’s pitch.

On September 23, 2012 at 5:34am
Oscar Darwin wrote:

When a web site representing itself as a serious scientific research and information resource descends into name-calling in a public forum…and the moderator condones such juvenile behavior…it speaks volumes about your academic qualifications and calls into question every conclusion therein. The military documents I referenced are in the public domain and readily accessible to anyone with basic research skills. I noted with great interest that you didn’t ask for a link to the documents but merely dismissed them out-of-hand with contempt. Perhaps your research skills were acquired at the same place you acquired your objectivity, scientific qualifications, common courtesy and manners!! For my part…I think I’ll now take the advice of a previous poster who admonished others to take everything here, “with a grain of salt.” After all…you’ve earned it!! Have a nice day.

PS - I also have a PDF transcript of a lengthy 1956 court case that challenged the claims of another battery “snake oil” remedy. In his decision, the judge states, “In view of the CONFLICT IN THE SCIENTIFIC EVIDENCE, the hearing examiner deemed the user evidence attesting to product merit to be particularly significant and he, accordingly, held the complaint’s allegations to be unsustained by the greater weight of the evidence.”

That document is also in the public domain but I’m certain you wouldn’t be interested in the link since it doesn’t fit your template. Happy hunting!!!

On September 23, 2012 at 5:57am
John Fetter wrote:

Oscar - Old news. Been there, done that. The 1956 court case involved Jess M Richie, bulldozer operator, and his magic potion AD-X2. I posted something on this on this website some time ago.

On September 23, 2012 at 6:05am
Oscar Darwin wrote:

Good for you!!  Then you should have no trouble finding the military docs as well. I’m sure everyone is anxiously awaiting your polite, scholarly and objective report on those as well. Everyone except me that is. Fare thee well.

On September 23, 2012 at 7:34pm
Chris C. wrote:

Take it easy, Oscar, these are legitimate objections! When you make claims, you have to be ready to back them up with FACTS. Come on, it’s Science 101!

You gave us NO LINKS to back up your affirmations. It would therefore seem to me that you have only yourself to blame for “name-calling”, as unsupported affirmations do indeed “speak[s] volumes about your academic qualifications”.

If, however, you are trying to protect a market, why not say so?

On September 29, 2012 at 4:59am
Pau C. wrote:

John Fetter- As you are well instructed in the battery desulphation and as you said….
“3.26 MHz resonant sulfur frequency desulfation makes no sense to me” therefore what would be the best frequency to operate in order to desulphate a battery?
And what should be the maximum peak of that pulses, would that be related to battery capacity or voltage? If you pulse that battery along the time how the pulses would have to act along the time related to battery impedance also would the peak decrease?

I would be appreciate much your opinion on the questions as I see you very experienced on the subject.

On September 29, 2012 at 5:21am
John Fetter wrote:

Pau C - I consider the 3.26 MHz concept to be an idea rooted in magic. Weird.
Just about any type of pulsing seems to work for batteries than are marginally sulfated.
Pulsing will not budge 100% sulfated batteries.
Pulsing seems to be something that could be described somewhat colorfully as “equalization charging on steroids”.

On October 16, 2012 at 12:02am
Jerry Malinski wrote:

I’m a seventy year old retired engineer and I’ve been following you comments with great interest. I’m in the process of going off the grid and plan on depending entirely on solar power. I started researching desulfation about three years ago and have learned a few things.  One is that it works with electronic pulsing. Two, even some shorted batteries can be brought back into service with a simple flushing process.  I use electronic circuits that are simple to make and monitor.  I’m not selling anything.  I will give the information to anyone who wants it for free.  It’s the battery companies who don’t want this information out there.  Pulsing is like sandblasting the crystals.

On October 18, 2012 at 12:20am
Jerry wrote:

Jerry you can write me at pcurrius@gmail.com about the electronic circuits to desulphate this 2V-48V banks of batteries. Thanks

On October 19, 2012 at 5:19am
Jerry Malinski wrote:

I don’t need any circuits.  I think I can design that part of it. The key is the frequency of the sulfate crystals.  The whole pulsing process is designed to bombard the crystals with a pulse at the right frequency (kind of sandblasting the crystals at a molecular level). This in turn breaks them up and allows them to go back into solution. At least that’s the theory.  If the crystals haven’t expanded and damaged the plates, they can be pulsed back into solution.  This is different than using an additive that breaks the crystals off the plates allowing them to fall to the bottom of the battery.

On October 19, 2012 at 6:03am
John Fetter wrote:

Jerry Malinski - Everything that has been said about lead sulfate having a resonant frequency and pulsing at that resonant frequency in order to desulfate a battery is anecdotal and empirical.
Marketing desulfation product 101. Step 1. Invent a problem. Step 2. Invent an explanation. Step 3. Create a product. Step 4. Sell the product.
Some people want to believe in miracles. Their minds will make the desired miracle happen.
Don’t get me wrong. A percentage of lead acid batteries get sulfated. A percentage of those sulfated batteries respond to pulsing. There are now so many desulfator entrepreneurs trying to sell their products, they gotta say something clever in order to stay in business. Caveat emptor.

On October 19, 2012 at 6:40am
Pau wrote:

So Jerry what’s the frequency you can think of the best? Or will it be a range of it?

On October 19, 2012 at 2:07pm
Jerry Malinski wrote:

John Fetter-I’m not trying to sell anything, anything I discover that will help restore my lead acid batteries and give them additional life I will share with the world for free.  No one invented the problem of sulfation, it’s a fact of science.  You seem to have a bitter taste in your mouth about this subject. In my seventy years on this planet I discovered manufacturers build products with a life span profitable for their business, not for the consumer.  If I can extend that life span I will, not with a miracle but with research and hard work.  My desulfating has worked, albiet slowly, but worked.

On October 19, 2012 at 2:14pm
Jerry Malinski wrote:

Pau-My son works for a large auto parts store and he gets me batteries people trade in for new ones just by paying the core charge.  He just gets batteries that won’t hold a charge.  He passes on the ones with shorted cells or if there is bulging.  The frequencies I’ve been experimenting with range from 900hz to1650hz. It seems between 1100hz and 1350 is a sweet spot but it can take up to a month and a half to bring one around. Lately I have been trying different amplitudes at these frequencies to see if that speeds anything up.  Jerry

On October 19, 2012 at 5:07pm
John Fetter wrote:

Jerry Malinski - If a lead-acid battery is used correctly, it does not become sulfated. If it is used in a way that results in the battery receiving insufficient charge, it is likely to end up becoming sulfated. These are the lead-acid battery “facts of science”.
The majority of desulfation product merchants make the claim that batteries become sulfated with age. There is not a single battery manufacturer who agrees with this - saying batteries wear out due to positive plate corrosion and shedding.
I have personally tested ways of de-corroding and de-sulfating batteries. I found both can be made to work.
There are many hundreds of battery manufacturers around the world. If there is one who makes batteries that last longer, curiously, no one could care less. That is because the overwhelming majority of people who purchase batteries will buy only the least expensive batteries. Automobile manufacturers are interested only in rock bottom price. Motorists are either looking for convenience or for the best price when they need a replacement. Batteries are a commodity. Batteries are a grudge buy. Manufacturers have no option. Make cheap batteries or perish. That is the battery business dynamic. The consumer, not the manufacturer, decides how long batteries last.
I have found pulsing works, in terms of desulfation, up to a point. It is ineffective on deeply sulfated batteries. Cadmium is slightly better. Switching the charger on and off, plus cadmium, for three weeks or longer seems to be the best.

On October 19, 2012 at 5:21pm
Carl wrote:

It seems as though battery sulfation, shorted and open cells, adding distilled water, and swelling of battery housing will be a thing of the past. I believe the following will render batteries obsolete. It is SUPER CAPACITORS! Battery University has an interesting article on SUPER CAPS. Below, are a few links that may be of interest, beginning with Battery University. Check these bad boys out! Oh, they are expensive!








On October 19, 2012 at 6:53pm
Jerry Malinski wrote:

John Fetter-I believe batteries become sulfated because of poor maintenance and neglect also, but that is an advantage for me. Being retired and on a fixed budget these rejected batteries are helping me build a solar bank without a huge expense. And it gives an old man something to do. Their garbage is food for my cat, so to speak.
And Carl your absolutely right, Super capacitors are the future battery.  I believe that is the answer for electric cars.  As a retired electrical engineer, who was around for the birth of the transistor and the microcontroller, I can see it coming. Jerry

On October 19, 2012 at 11:49pm
John Fetter wrote:

Jerry Malinski - My budget has let me study the subject of battery life unhindered by constraints. I have a reasonably well equipped lab. I have managed to figure out the lie of the land, in a manner of speaking, with regards to batteries.
If you can convert batteries that other people discarded into cash, that’s absolutely wonderful.
You might find the following useful. A percentage of the discarded batteries will respond to plain charging. A percentage will respond to pulsing. A percentage will respond to cadmium. And a percentage will not respond at all.
You can obtain cadmium in the form of cadmium oxide from electroplating suppliers.
A high percentage of these batteries will be low maintenance, zero maintenance calcium alloy.  They will be suffering from “open circuit”. They will respond to pulsing.
To obtain maximum return on your work, treat your batteries with cadmium, then pulse charge. The spiky pulsers are useless. You need something that pushes out proper power. You cannot desulfate without supplying the batteries plenty of EXTRA energy.
Carl - Think about this. The amount of energy held in a tankfull of gas translated into its electrical equivalent, would require nine out of ten existing electricity consumers to be disconnected to allow the ten percent of electric car owners to recharge their batteries.

On October 20, 2012 at 1:57am
Jerry Malinski wrote:

John Fetter- I have a pretty good lab too, acquired over the years, Is there a formula or mix for the cadmium additive?  After looking at some of the Super capacitor links Carl posted I’m tempted to throw one of them into a pulsing circuit. That would sure shake the crystals out of the sockets.  Of course, standing a safe distance away. rea Jerry

On October 20, 2012 at 4:08am
John Fetter wrote:

Jerry Malinski - I researched this subject in considerable detail. I read the scientific papers and books written by acknowledged battery experts and read the anecdotal, empirical garbage. I have posted quite a few comments on the various pages devoted to lead-acid on this website’s pages.
Fifty percent of the active material that is put into the plates does not participate in the battery reactions. It provides conduction. There is no other way the other fifty percent can work. Sulfation of the active material is normal. Without it batteries cannot work. Sufation crystals growing beyond a reversible size is a wonderful story. I have been unable to find any evidence in support.
The “unused” fifty percent sits underneath, out of sight, out of mind. It becomes sulfated when the battery is neglected. That then leaves the active active portion in a precarious situation. I believe that is the true cause of “irreversible sulfation”
It is not difficult to work out what to do from an electrical, electronic, chemical perspective about this problem. The electrical transmission path has gone high resistance. That can be overcome by application of high voltage. Well, almost. Better still, infiltrate the now-sulfated support material with electroplating. That is where the cadmium comes in. It grows like fine grass onto the negative grids, in every direction. Helps to improve conduction. It is important to switch the charger on and of cyclically, to reabsorb and replate the cadmium. Takes many weeks.
One level teaspoon cadmium oxide per 60 Ah cell. Cadmium oxide is not soluble. It reacts with the acid, slowly forming cadmium sulfate.
Carl - Super capacitors designed for supplying energy cannot not store more than a tiny fraction of energy compared to lead-acid. That is why many are built into lead-acid batteries. Identical positives, dual negatives. Half being lead-acid, the other half capacitor. Very good at supplying and absorbing very high currents for short periods. Very good at controlling sulfation. Very expensive. Batteries do not obey Moore’s Law, like semiconductors. The problem that besets batteries, limited energy storage, cannot be solved. However, there are some ingenious ways around the problem. Right now, peoples’ emotions are getting in the way of accepting these solutions.

On October 20, 2012 at 12:17pm
Jerry Malinski wrote:

John Fetter= The only problem with electroplating with cadmium is “Cadmium is subject to the spontaneous growth of Cadmium whiskers. The propensity of Cadmium to grow whiskers appears to be lower than that of zinc and especially tin. Cadmium whiskers (like tin whiskers) grow spontaneously and are capable of causing electrical failures ranging from parametric deviations to sustained plasma arcing that can result in catastrophic short circuits.”. It is also a cumulative poison. What gases would be released when mixed with sulfuric acid.  Jerry

On October 20, 2012 at 12:43pm
John Fetter wrote:

Jerry Malinski - Oh yes. But you want the whiskers. Cadmium is useless in lead-acid batteries without the whiskers. Whiskers can only grow so far before the cadmium that is in solution becomes depleted. Then you switch off the charger and wait. The cadmium goes back into solution. Then you switch on again. And so on until conduction is restored. You need to take the cells up to 2.6 volts each time. When you have finished, the density of the cadmium whiskers will be so dispersed, you won’t notice a thing.
Putting metals into sulfuric can liberate hydrogen. Putting oxides into sulfuric liberates water.
Things are relative. Cadmium is a poison. So now lead is not a poison? Comparing a couple of grams of cadmium with over 10 kilos of lead. The tyranny of numbers.
I am not promoting this cure. You were saying I have a bitter taste in my mouth about this subject. I have tried every desulfation trick. I found this one to be the best. That is all I am saying. I personally believe there are far, far better ways of getting the most out of batteries.

On October 20, 2012 at 1:25pm
Jerry Malinski wrote:

John Fetter- I posted cadmium being a cumulative poison not so much for you but for the internet audience who will take our comments and experiment without any research, Some clown will probably sell it on eBay as a battery cure-all without explaining its dangers. My “bitter taste” comment wasn’t derogatory, it was pointing out that your distaste for the “Medicine men desulfator salesmen” was coming across loud and clear. Most of the stuff they sell is worthless and that’s why I started my study.  My goal of acquiring and maintaining my solar battery bank is progressing nicely and I thank you for your help with that.  I will experiment with cadmium and see where that takes me.  Jerry

On October 20, 2012 at 1:52pm
John Fetter wrote:

Jerry Malinski - Lead-acid technology is a bad choice for solar. These batteries are operated partially charged. The problem is sulfation. Conventional lead-acid is doomed to a short service life unless you can bring them all the way up to full blown gassing charge at reasonably regular intervals. The correct choice is probably nickel-iron.

On October 20, 2012 at 2:15pm
Jerry Malinski wrote:

I agree with you a 100%. NiFe batteries are the best for solar applications.  But I just can’t afford that right now.  The Edison battery would eliminate all the other problems.  Jerry

On October 20, 2012 at 9:40pm
Chris C. wrote:

The discussion in the past months on this site has been nothing short of astonishing. Kudos to John, Jerry and Bevan for keeping this subject alive and under active research.

I do agree with John that its is difficult and certaib=nly not cost effectiive to reverse lead plate sulfation. Lead acid battery chemistry, although ubiquitous and made with inexpensive materials hence inexpensive, is far from ideal for true energy storage as it works best only if it is not called upon to be used at all wink

I have been using automotive type “deep cycle” batteries for the past 12 years now in my truck and to be honest, performance improvement in heavy use (read: with accessories using power with the engine off) has been modest at best. Do I feel it is an improvement upon standard start batteries? Definitely. Are these so called deep cycle batteries less prone to sulfation? Definitely NOT! Their only redeeming quality, IMO, is the fact they can actually be filled with deionized water for the purpose of gassing them off for equalization purposes, and that they can be restrored to working condition with lots of effort. But if you’re the type who likes to fit it in and forget it… You’ll quickly find out they need much more maintenance than regular start batteries.

But making batteries last more than 5 to 8 years and be easily recharged after an accidental complete discharge? That hasn’t happened with thee “deep cycle” batteries and John’s explanation that internal grid compounds probably are the culprits and do get sulfated, explains the problem very well.

I therefore suggest that perhaps the problem with sulfation really lies with current grid design. Maybe it would be time to get back to a sheet design, where reactions are limited only to the surface, rather than the current powder/sponge design. Hey, congratulations, I just reinvented the Optima battery design wink

On October 20, 2012 at 11:22pm
John Fetter wrote:

Jerry Malinski - There are numerous patents for pulsing solar powered lead-acid batteries. A patent does not automatically mean a technology works, it merely reflects the inventor’s ability to think outside the box. I found more than 70 patents related directly or indirectly to pulsing lead-acid batteries for the stated purpose of desulfation.
If you are still looking for a way of making lead-acid solar powered batteries last longer, it suggests that you have not been able to get any of these “technologies” to work. Is my assumption correct Jerry?

On October 21, 2012 at 4:18am
Jerry Malinski wrote:

John Fetter- No, your assumption is incorrect. I have a circuit that has brought six different batteries I acquired from between 50 and 60% to a near new condition. I also had one battery with a shorted cell that i dumped the acid into a container and flushed out the battery with distilled water and poured the acid back. This was a new battery put in a car and sat for a year.  When the car went back into service the cell shorted out and it was given to me. That battery is in like new condition now.  My problem isn’t that it’s not working (the pulsing) but that it is so slow. Weeks, sometimes months. Leading me to believe the frequency or the amplitude or both are wrong.  Jerry

On October 21, 2012 at 4:53am
John Fetter wrote:

Jerry Malinsky - Let me try again. On October 16 you said you are in the process of going off the grid and going solar. It might be a good idea not to let any car battery issues interfere with the solar situation, just yet. I have been under the impression your objective is keeping your solar lead-acids free from sulfation and that what you managed to achieve is short of what you believe you need. Alternatively, are you acquiring discarded batteries and hoping to get them working well enough to be used in your proposed solar system?
Perhaps you would like to share some information about what you have tried. Then we can try to work out some kind of solution.

On October 23, 2012 at 5:48pm
Ev Rea wrote:

Hey Guys - Would there be any benefit or harm done by zapping a 12 volt battery with 24 volts for very short periods?

On October 27, 2012 at 3:38am
John Fetter wrote:

Carl Gali received a patent for pulse desulfation in November, 1991. He was the first “desulfation pulser”. Robert Gerbman received a patent for pulse desulfation with a pulse rise time between 200 and 500 nanoseconds, (5 MHz - 2 MHz) in February, 2001. He spoke of 3.26 MHz as the resonant frequency of sulfur crystals (?) and implied that zapping these crystals at 3.26 MHz would restore a sulfated lead-acid battery. According to the best sources of information available, there are no sulfur crystals in lead-acid batteries. It is convention either to to disclose the source of information on which a technology described in a patent is based or to describe its function. Significantly, Gerbman does neither, reducing the value of his patent, in terms of genuine intellectual property protection, to a fat zero.
Gali’s patent is reasonably credible, although not strong. Gerbman’s patent is pseudo-science.
Certain people with a keen eye for opportunity and a strong desire for profit have been turning the Gali and Gerbman patent disclosures into products, with impunity.
The suggestive power of advertising copywriting has people scrambling for the optimum frequency at which to desulfate batteries.
The reputation of desulfation cures deservedly continues to plummet.

On December 1, 2012 at 6:41am
John Davies wrote:

The people who vouchsafe for pulsing batteries seem to me to come across as the same mentality as people from the early days of medical science.

Just give the patient a good electrical shock. That will cure almost anything that ails him..

Very interesting discussion though and I totally agree with John Fetter’s comments about battery failure and compacted sulphation.

On December 7, 2012 at 1:02am
Lee wrote:

EDTA, which is ethylenediaminetetraaceticacid - tetrasodium salt,also known as N,N’-1,2- Ethanediylbis[N-(carboxymethyl)glycene] tetrasodium salt is used to dissolve sulfate deposits from lead acid batteries. The pulse chargers simply give the battery a higher than normal charge voltage for a brief period which “helps” break up the sulfation from the high voltage but doesn’t overheat and gas them because it’s cycled on and off. They don’t tell you why (assuming they actually know) because it’s so simple. I do the same thing by hitting the “jump start” button periodically.

On December 7, 2012 at 1:26am
John Fetter wrote:

Lee - EDTA does not dissolve but sequesters lead sulfate. The lead sulfate is taken out of service permanently - equivalent to stripping out portions of active material.  It is bad science.
Some of what you say about pulse charging is undeniably correct. Batteries that have been slightly neglected and are “mildly sulfated” respond well to being given a pulse charge. Seriously sulfated batteries absolutely do not respond to pulsing. Maintenance-free batteries that have died suddenly often suffer from another problem altogether. A PbO/ sulfate insulating layer between the positive grid and PBO2 positive active material. Pulsing gets rid of this barrier and the affected battery regains most of its former performance.

On December 7, 2012 at 1:50am
Lee wrote:

John Fetter, If you spent half the time that you flap your jaw here and simply research the web you would say “WTF is Fetter talking about?” The sulfuric acid reacting to the battery plates when a load is placed on the battery deposits the sulphate on those plates, that’s the delivery of power part that also lowers the hydrometer reading (less acidic), charging simply reverses the process, but if not recharged enough to clear the sulphation and allowed to go thru a few charge/discharge cycles allows new sulphation over the existing then off the existing sulphation with those charge/discharge cycles and that “soft” sulphation gradually builds up layers and becomes “hard” sulphation, like the anodizing process does to aluminum when sitting in acid/distilled water + volltage/current application. If you pour out the electrolyte, fill with distilled water only and cycle it a few times (charge/discharge) and the water ph level starts going up/acidic, from the electro/chem charging, removing sulphation from the plates and depositing sulfuric acid in the distilled water. Didn’t mean to type so much and still didn’t totally describe it…..

On December 7, 2012 at 2:18am
John Fetter wrote:

Lee - Thank you for sharing the information you picked up about lead-acid batteries recently.
There is a difference between information acquired through reading and information acquired through hands-on experience. However, one needs to do both in order to get a proper handle on the subject.
(As an aside, I noticed a curious relationship between 555 IC timers and lead-acid batteries. The more people profess to know about 555 timers, the less they seem to know about batteries.)

On January 7, 2013 at 9:31am
Khurram wrote:

Dear sir I have following questions for you.
Sir I am having the problem that some times my inverter keeps on charging the battery for no reason for long hours and some times it terminates the charging all by it self after a reasonable time of charging.

Following are the reading of Hydrometer from the battery;

• Inverter remained off for 24 hours and input of inverter from main socket was disconnected and the reading on battery terminals was 12.5V.
Hydrometer readings are as following;
Cell no 1= 12.4
Cell no 2= 12.4
Cell no 3= 12.4
Cell no 4= 12.7(I added 30 ml distal water in this particular cell and then the reading was 12.3)
Cell no 5= 12.4
Cell no 6= 12.4
• Then I inserted the input of inverter into the main’s socket and inverter charged the battery for 45 minutes and terminated charging the battery after that. I took the readings on the battery terminals and it showed 13.7V. (the inverter manual states that this inverter charges the battery on 13.7V).
• Then I cut off the main and checked the out put on one of the socket’s for output voltage of battery and it showed 192V however, LCD indicator on inverter was showing 220 V as output voltage.
• After 5 minutes I resorted the main’s input to inverter and it started charging the battery for approximately 40 minutes then I turned off the power button of inverter and it stopped charging the battery immediately.
• Voltage reading on battery terminals was 13.7V while the inverter had stopped charging the battery.
• After 3 minutes voltage dropped to 13.4 V.
• After 20 more minutes voltage further dropped to 12.9V.
• Then I removed the inverter’s input from the main and inverter was also in off position after 2 more hours voltage reading was 12.6V.
• After the passage of 15 hours battery output voltage was 12.5V and voltage has remained the same even after 36 hours. (inverter is still in off mode while the input of main has been disconnected however, inverter cables were connected all the time with the battery.
It is quite strange that when my inverter keeps on charging the battery for some time and then I rapidly turn off main’s input to inverter and then restore it some times inverter stops charging the battery and some times it doesn’t. 

*    Battery was fully charged and inverter terminated the charging by it self. I turned off main and checked inverter’s output directly from inverter’s AC out let and the reading was 176 V while there was no load on inverter. However, LCD indicator on inverter screen was showing 220 V output.

2nd Step:
I connected the phase wire in inverter’s out put socket and turned on 2x 23 Watts bulbs and inverter showed 184V output voltage in another socket of the room. Gradually volts increased to 192V.
When I tuned of the both bulbs (when there was no load on the inverter it once again shows 179 V in the same socket).
3X 23 Watts bulbs load on inverter, reading in socket showed 195V.
4X 23 watts bulbs load on inverter, reading in same socket increased to 198 V and then I turned on a 40 Watts tube light and volts increased to 205V.
4x bulbs+ 2x tube lights, voltage in socket 202V.
Then turned every thing off, meaning there was no load on the inverter and reading in socket gradually reduced to 179V.
I repeated these steps three times and readings were strange. However, voltage output of inverter seemed to fluctuate while increasing the load or decreasing it. When there is some load on inverter during power outage then output voltage is better as compared with the inverter running without any load.
3rd Step:
2x 23 watts bulbs load on inverter, reading in socket = 191V.
3x 23 watts bulbs load on inverter, reading in socket = 195V.
4x bulbs + one 40 watt tube light, reading in socket =  202V.
4xbulbs + 2x 40 watts tube lights, reading in socket = 199V.
4x bulbs load on inverter and when I turned off both tube lights reading in socket was 212V.
Turned off all loads and reading from socket was once again 179V.

Meanwhile, when main is restored the LCD indicator on inverter shows the voltage which precisely corresponds with the voltage readings in the socket i.e inverter LCD indicator shows 129V as well as regarding on socket shows 128 V or 127V.

However, the reading on battery terminals was 12.1 V during this time.

Another thing which I have observed that when I charge the battery and inverter terminates the charge then I switch off everything including the inverter so that nothing drains the battery. When I took measurements using a volt meter then the battery reading was 13.3 V and after few minutes it seemed to gradually drop to 13.2 and so on. My main question is that is my inverter the culprit or my battery has some issue. 

On January 7, 2013 at 2:06pm
Chris C. wrote:

Wow, Khurram, what a lengthy post!

3 things come to mind:

Have you double checked the voltage readings of your AC output with another meter? Inverters are notorious for fooling all but the best of meters, because of waveform, as even RMS aware meters are designed for true sine wave. Most inverters are modified sine wave, or more appropriately, modified square wave.

Secondly, check the battery voltage over a month. That will tell you resting voltage (after a day or so unconnected), which should then remain pretty much stable for the next few days, with only a very slow decrease after that. A fast decrease indicates a bad battery. Normally, a wet cell lead acid battery fully charged at rest should be between 12.65 and 12.75V after a day of rest, after that it should drop no more than about .15V over a month, but it depends on battery chemistry and the climate your battery is sold for.

Which brings me to the third point: I understand you probably meant 1.24 electrolyte density, not 12.4. Which would indicate that your battery probably has the warm climate electrolyte density, that would be normal. What would be abnormal is to have a greater than .01 (some say .05) difference between cells, that would indicate a problem in one cell, which can often be solved by equalizing (overcharging until poor cell electrolyte density is up to the level of the others, and keeping an eye on electrolyte level). Furthermore, you cannot get good readings if your charger doesn’t churn the electrolyte, as it does during equalizing, otherwise the electrolyte might be stratified, with the weakest solution up top.


On January 8, 2013 at 12:19am
John Fetter wrote:

Khurram - There isn’t actually all that much usable troubleshooting information and we are left guessing about the inverter and about the battery.
The output waveforms of inverters vary, depending on price. The cheapest has a square wave output. A more expensive type has a quasi square. The most expensive a sine wave.
Different waveshapes can give a different voltage readings on the same meter. Not only that, different types of voltmeters can also give different voltage readings. Some meters read average, some RMS.
Your inverter seems to have a control circuit that senses the battery voltage and decides whether or not to charge. Battery voltage is never a foolproof indicator of state of charge. So the system ends up “hunting”.
The inverter output voltage control appears to be slightly overcompensating. Not a problem.
The cell that needed water might have a problem. Something is causing it to gas more than the other cells. This could be due to an impurity or lower capacity, even aging.

On January 8, 2013 at 4:58am
Khurram wrote:

Thankyou so much for your kind replies yes Mr Chris and Mr John Fetter. I have doubled checked AC output readings using another meter as well, there is only difference of 2 to 4 Volts. If I turn off the inverter and pull the plug then the voltage of battery seldom drops over a period of 24 hours or so. i.e; when inverter had fully charged the battery then I disconnected the input of inverter and turned it off but the wires of inverter were still connected with the battery and after 30 hours reading on battery terminals was 12.48 V. however, I have noticed one thing when inverter fully charges the battery and voltage reading on battery terminals is 13.4 V or 13.7 V and it remains on and when power goes off and even when one 23 Watt bulb is running on inverter then the battery voltage drops to 12.1V within few minutes but it remains at 12.1V for more than an hour even if 120 Watts load is running on it.
Yes, your right I have Exide NS 200 AH battery which is the biggest in this region and it is made for wormer climate, usually temperatures during summer seasons are from 30 C to 44C and it performed excellently during summer months but after 7 months now it is winter season and I am having problems. Winter temperatures are 3C to 10 C nowadays.
If I use inverter for 15 minutes to run 23Watts bulbs and after restoring main power inverter tends to charge the battery for one and a half hour then I turn off the input of inverter and after few seconds turn it on then it stops charging the battery, I guess this indicates problem in the inverter?   
      Well Mr John Fetter your right it is a simulated sine wave inverter but I have a question that when main is on the LCD indicator of inverter i.e; shows 229 V input and when I check the readings in one of my room’s socket the AC readings are 226 V etc, meaning almost corresponding readings. The main problem is when battery is fully charged and if main goes out LCD indicator on Inverter shows 220 V output but readings show 176 V in the socket and when I turn on few bulbs and tube lights the voltage readings increase. I understand your point that modified sine wave inverter’s might deceive the volt meter. Now I do not operate my PC and LED monitor any more on inverter outlet because I am afraid that low voltage could be detrimental for these appliances.
I have another question that why my inverter stops charging the battery when I turn it off and then turn it on again within few seconds. But this technique only works when inverter had charged the battery for at least for 70 to 90 minutes.
Second thing is that when I add little bit distal water and after wards shake the battery once after that for two to three days inverter does not seem to overcharge the battery and if power outage lasts for an hour and 60Watts load is on and after restoration of power inverter fully charges the battery for one hour and then automatically terminates the charge, but after three to four days it starts behaving abnormally, power outage lasts for 15 minutes when 23 Watts load is on inverter and it tends to charge the battery for one to two hours. This is strange phenomenon.

I have Cyberpower Inverter “CPS 1200 EI LCD” and following are the specifications;

Model CPS1200EILCD
Capacity (VA / Watts) 1200VA / 720W
Frequency Range 50Hz / 60Hz
On Battery Output Voltage Simulated Sinewave at 220Vac +/-10%
On Battery Output Frequency 50 / 60 Hz
Overload Protection* On Utility: Circuit Breaker/ On Battery: Internal Current Limiting

Lead Acid Battery 12V
Charging Current 10A
Warning Diagnostics
Indicators AC Mode, Battery mode, Fault
Audible Alarms Low Battery, Overload, Fault
Auto-Charge / Auto-Restart Yes

4. Charger Control*
A. Select “Default” setting for general application. The charge voltage is 13.7V
respectively for CPS1200EI .
B. Select “Customized” setting for special battery condition. The charge voltage is 13.3V
respectively for CPS1200EI.

On January 8, 2013 at 7:01am
John Fetter wrote:

Khurram - You can measure a voltage of ANY waveshape using two lamps. One lamp connected to the mains, one lamp on the output of the inverter. Compare their brightness.
A quasi-square wave might cause oscillations in long housewiring, or interact with transformers and/or motors that are connected and cause your voltmeters to read an unexpected value.
Most computer power supplies are switchmode and are happy with 90 to 245 volts. Any decision to use or not use tends to be overridden when you find you really must use your computer.
I think you may be causing the inverter control circuit to become confused by the way you are switching the system.

On January 8, 2013 at 12:49pm
Chris C. wrote:

Khurram, I have a fairly similar emergency power setup to yours (1000W inverter and group 27 ‘deep cycle’ marine battery for a couple CFLs, laptop and small chargers), except that I use an independent charger and use manual equalizing, which, I assume from your posting, your setup doesn’t do. If one cell is weak, it will bring down the whole battery, and if the situation is not corrected it could ruin it.

Therefore, it is important to equalize the battery, which means to slightly overcharge it, controlling temperature and checking electrolyte level as you do so, until the weak cell electrolyte density has reached the same level as the others. This could take hours if the problem is benign, or days, if the sulfation is severe. The important thing to remember is to keep current and temperature low to avoid rapid internal corrosion (now would be a great time for you to do it, it seems).

Once fully equalized you could double check the cell measuring its internal voltage putting the probes through the cell on the bus bar (careful not to jab the plates, it could short the cell).

If equalizing doesn’t bring back the cell to normal behaviour, it may be shorting internally, causing it to not being able to accept a charge. If it’s caused by dendrite formation it is possible to zap the offending cell by shorting it, but it can be a dangerous procedure. I’d do that only in the last resort and only after emptying the offending cell and refilling with distilled water.

Getting back to temperature, with a weaker electrolyte the battery will be more affected by dropping temperature due to lower chemical activity. I’m not sure how it works out for your normal electrolyte concentration, but a 30C temperature drop will have a measurable effect on power output.

As for your inverter behaviour, the only thing that comes to mind is that it may actually be trying to compensate for low temperature or a weak cell.

I would suggest you look into the manual as to whether it is possible to set it up for equalization and whether you can increase charging voltage to 14.4V, keeping in mind that this may increase battery internal temperature during charging and require more frequent distilled water addition.

On January 9, 2013 at 2:57am
Khurram wrote:

Thankyou so much gentlemen for your replies I will do my level best about the procedures you told me. 


On January 13, 2013 at 8:00am
stephen wrote:

Hi guys

I have an 18-month old 100Ah leisure battery in my caravan. Recently I foolishly left a low-speed heating fan (not the heater itself!) on for 10-14 days and when I discovered it the voltage was 0. I have reacharged the battery with the caravan recharger and after 48h it retains a voltage of 13v (slightly higher than it did before).

I am not sure how severely am I likely to have damaged the battery or what useful tests I could do, and would be grateful for any comments and advice about immmediate management.

On January 13, 2013 at 9:14am
John Fetter wrote:

stephen - The load was quite low and the likelihood of permanent damage is therefore low. Cell reversal might have occurred but not too seriously. The negative plates don’t like it very much. You will get no sulfation. Simply charge, as you have done. I would continue trickle charging at a few hundred milliampsfor up to a week to fully restore the plates and balance the cells. Keep the voltage at about 14.5 but no more.

On January 13, 2013 at 2:38pm
Chris C. wrote:

This has happened to me a couple of times as well and I was able to get the battery back in shape, but I wouldn’t be as optimistic as John even if the battery voltage seems to indicate it probably didn’t suffer, because the longer the battery stays in a discharged state the greater the chance amorphous lead sulfate will grow into large crystals that cannot be reverted back into lead and sulfuric acid.

Anyway, check the electrolyte level and density in each cell. That will tell you much more about battery health, and equalize charge as necessary, as John suggested.

On January 14, 2013 at 4:45am
stephen wrote:

Thanks guys thats very helpful

On January 17, 2013 at 12:14am
James Bond, Jnr wrote:

SIMPLE OBSERVATION: Virtually zero auto spares, hardware, etc. retail outlets carry desulfating products on their shelves. That should be enough proof these things don’t work.

On January 17, 2013 at 1:08am
Pau wrote:

Sulphation stages occur in this manner divided by market division:

- Solar batteries (they can keep half of the year discharged)

- Traction batteries (they charge and discharge)

- Starter batteries (sometimes they charge and discharge or users leave them unattended for a long period of time. Also warehouses can keep them for more than 6 month on the shelve)

- UPS batteries ( floating charge)

This would be from more to lees that quantity of sulphate that you can find in a battery. That would mean that if you try to regenerate a UPS battery, you are almost dead, on the contrary you can find a solar battery completely sulphated. Even if you find both of them at correct voltage and low density, internal problems can be different!!!

technical department at renobat


On January 17, 2013 at 2:29am
James Bond, Jnr wrote:

It is common knowledge that batteries get sulfated. The big question is whether or not they can be “desulfated”. The almost 100% absence of desulfation products from retail outlet shelves conveys a very powerful message.

On January 17, 2013 at 4:32am
John Fetter wrote:

Pau - You are evidently not familiar with large motive power and large standby battery facilities. The batteries in large facilities make up over 95% of these types of batteries. They absolutely do not become sulfated because they are used correctly.
Sulfation occurs, in descending order, in many leisure marine & light aircraft batteries, some truck & automobile batteries, a fair number of cold-winter golf-cart batteries and a smattering of underutilized forklift batteries.
The people in the desulfation trade are overwhelmingly not originally from the technical side of the battery industry.

On January 21, 2013 at 8:42pm
Jack wrote:

Interesting thread even if it does degenerate into the odd name calling. Such is the internet.

I think there was a comment about adding graphene above.

Not sure how many are aware, but many companies are looking at building and or incorporating aspects of Lead-Carbon battery technology from full up electrodes, to additives. The full up versions appear to have no or limited issues with partial discharge, not to mention 5-10x the cycle life at about 2-3x the price right now.  I think Exide has an automotive battery now with carbon additive that claims to have much longer life.

I am surprised there was no mention of some of the advanced charging algorithms that NREL developed in the late 90s/early 2000s. As opposed to the typical 14.5ish charge voltage, they actually charged as high as 17+ volts for part of the cycle looking for the point at which the delta voltage approached zero. This could be interpreted as the point where almost all sulfur would be removed from the negative plate. They then continued with a somewhat typical small absorption overcharge. The tests I remember were done with Optima batteries. They were able to achieve 2x+ the number of cycles.

Of course, there was some pulse charge algorithms that were promoted for similar batteries (spiral wound) that actually reduced the number of charge cycles for flat plate batteries.

I do have an interest in any way to prevent and/or reverse sulfation for VRLA batteries (primarily AGM, but GEL too) in solar applications.  I do custom charge electronics so I have quite a bit of flexibility in what I can accomplish and always looking for an edge. There appears to be some competitors promoting sulfation prevention, but not much in the way of real world feedback.

On January 22, 2013 at 8:44pm
barry b wrote:

does epsom salt work to help desulfate a battery   or is this a myth if it works whats the best way to use it

On January 23, 2013 at 2:12am
John Fetter wrote:

Jack - A very useful source of information about carbon-in-lead-acid begins at the United States Patent & Trademark Office website, uspto.gov/patents/process/search - enter “lead acid” as the first search expression, “carbon” as the second search expression. The patents often carry the names of the corporations that own the patents. Carry on searching, corporate names, via popular search engines and a world of useful information becomes available.
What becomes evident is that the majority of carbon-in-lead-acid corporations are finding it difficult to make decent progress in the unforgiving world of business. Their batteries are apparently too expensive. This is very unfortunate. It seems that the lead-acid battery has become a mere commodity. Batteries are a grudge buy. People will buy only the cheapest. Graphene is an ultra expensive form of carbon.
If you want to charge a battery very quickly, two things need to be taken into account. Temperature of the battery, rate of gas evolution. Simply attach a temperature sensor and a gas flow sensor. Charge at high current and use the sensor outputs in a normal feedback control circuit to limit the charging current.
VRLA naturally sulfate through oxygen recombination. Awful technology. Designed by marketing people, not engineers. Much better to use a catalyst to recombine the O2 and H2.

On January 29, 2013 at 3:12am
Khurram wrote:

Hello Mr Chris C and John Fetter. I hope your doing good. I checked the readings on the battery terminals after charging the battery for approximately 4 hours I turned off the inverter and removed all connection cables and took a reading on 200AH battery terminals which was 13.17 V and after one hour readings was 12.90V (note there was no load on the battery, as all the cables were removed) after one more hour reading was 12.46V and after 28 hours reading was 12.36V. My question is that why readings are automatically dropping on the battery terminals when there is no load? As inverter was also disconnected from the battery. I also checked the internal voltages of individual cells using a procedure like connecting the positive probe of the multi-meter with positive terminal of the battery and then submerging the negative probe of the meter into electrolyte of individual cell, one by one. Readings were as following;
Cell no 1= 1.98V, Cell no2= 4.17V, cellno3= 6.33V, cellno4=8.48V, cell no 5=10.62V, cell no 6=12.76V. To make sure I took readings three times. 
After one hour readings were like this( all cables from battery were removed as well as inverter); cell no 1= 1.92V, cellno2= 3.99V, cell no3=6.06, cell no 4=8.13, cell no 5=10.19V, cell no 6= 12.26V.

I also noticed one thing that if battery is full and I only run 23Watts load on inverter for one hour inverter takes 2 to 3 hours to charge the battery before terminating the charging and some times it does not terminates charging at all.

On January 29, 2013 at 4:32am
John Fetter wrote:

Khurram - You may, inadvertently, be looking for a problem where there is none. Your battery is doing what all other lead-acid batteries have always done.
The plates of a recently charged battery include chemical species that exhibit an elevated open circuit potential. These dissipate over time. The battery settles down to its stable open circuit voltage after several hours, perhaps even a day or two.
Your final reading of 12.36 seems to suggest your meter could be under reading slightly.

On January 29, 2013 at 4:37am
Chris C. wrote:

Voltage is higher just after charging because of the surface charge, which dissipates under no load condition within a day, this is normal. Voltage drop after that first day depends on self discharge and is a different phenomenon.

From your readings, it appears your measurements were made from one battery post on one probe to the bus bar in each cell with the other. From that we can determine that battery voltage for each numbered cell (n) is: V= V(n=1)-V(n), so:

test 1 (V) test2 (V)

1: 1.98 1.92
2: 2.19 2.07
3: 2.16 2.07
4: 2.15 2.07
5: 2.14 2.06
6: 2.14 2.07

Differences between tests are not significant, since it appears measurements were done while the battery still had surface charge, so voltage drop would be normal under these circumstances.

What it does tell us, however, is that Cell 1 definitely looks weak. Have you measured electrolyte density of each cell? Cell 1 could be partially sulfated. Does the battery wall present any bulging?

If the cell wall appears flat, there is a good chance it hasn’t been damaged by sulfation and it simply needs equalizing, which is overcharging while keeping the cell temperature reasonable and topping up electrolyte levels as necessary, so as to bring back the weak cell to proper electrolyte density and voltage. You do need a hydrometer to properly monitor this!

As for a light load causing the charger to run for a long time - the only way to find out if it is a problem would be to measure actual power consumed by the charger. For this you would need an inductive ammeter in the charging circuit to measure power consumed by the charger during the procedure.

In any case, as long as cell 1 is not improved upon by equalizing you, will have issues like that.

On January 29, 2013 at 4:39am
Chris C. wrote:

John, are you an early bird? wink

the measurements would seem to indicate a slight problem with cell number one, don’t you think?

On January 29, 2013 at 5:32am
John Fetter wrote:

Khurram posted his SG readings on January 7. Cell No 4 different to the others, added water. There seemed to be nothing wrong with No 1.
The method Khurram used to measure the cells included negative electrodes in series for all the cells except No 1. This means cells No 2, 3, 4, 5 and 6 had proportional cumulative negative electrode potentials in series but not No 1. The first cell must therefore give a different, although not necessarily bad reading.

On January 29, 2013 at 5:48am
Chris C. wrote:

OK John, I had forgotten about that earlier post and ‘bad’ cell #4.

However, how can cell 1 read so differently if Khurram is measuring series voltage? Are you saying it’s caused by meter inaccuracy at the lower end of the scale? In which case measuring voltage between each cell instead would give much more accurate results?


On January 29, 2013 at 7:15am
John Fetter wrote:

Chris C. - Cell No 1 reading includes the electrochemical potential of the positive but not of the negative plates. There is a negative potential but that is generated by the probe reacting electrochemically with the acid. The reading at cell No 2 includes the previous positives, plus the No 1 negative plus the probe. And so on. The negative of cell No 6 never features.
Every cell reading includes a corresponding number of positive readings.
Every cell reading includes one probe-acid electrochemical reading.
Every cell reading except No 1 includes a corresponding number-minus-one negative readings.
Hence No 1 reading will be different.

On January 29, 2013 at 7:28am
Chris C. wrote:

John, I was wondering about the reaction with the probe… Your explanation makes a lot of sense. I tip my hat to you, glad to have learned something useful today smile

On January 30, 2013 at 2:52am
Khurram wrote:

I have checked the readings using multi-meter while the battery was disconnected from the inverter for 3 days now. Same process as before positive terminal of multi-meter was connected with the positive terminal of battery and negative probe was submerged into electrolyte of each cell one by one. Last readings were taken on 28Th January and after two days on 30 January readings are as following.
Cell no1= 1.85V, cell no 2= 3.93V, cell no 3= 6.00V, cell no 4= 8.05V, cell no 5=10.10V, cell no 6=12.16V
However the reading on terminals of the battery was 12.35V.
I used another procedure submerging the positive probe of multi-meter in one cell and negative probe in the electrolyte of another cell and regarding were; cell no 1= 1.86V, cell no 2=2.51V, cell no 3=2.50 V, cell no 4= 2.48V, cell no 5= 2.48V, cell no 6= 2.48V. However, you would have noticed the reading of cell no 1 is fairly different from others the reason for that is that cell no 1 reading was taken submerging the negative probe into electrolyte of cell no 1 while the positive probe of the meter was connected with positive terminal of the battery.
Hydrometer readings. Cell no 1= 1.21, cell no2= 1.21, cell no 3= 1.20, cell no 4=1.20, cell 5=1.20,cell 6=1.20.

My multi-meter is a new one and its readings are accurate. Inverter charges the battery on 13.7V, I have checked that and manual of inverter also states 13.7V. Charging current of inverter is 10 Amps.

On January 30, 2013 at 4:29am
John Fetter wrote:

Khurram - It seems you are very determined there has to be a problem. Maybe you have warranty issues. The very last suggestion I will make on this topic is to recommend you take the identical measurements on another battery.

On January 31, 2013 at 2:55am
Khurram wrote:

Yes, I have warranty issue for inverter not the battery and in our region batteries are only warranted for 6 months and now it’s been eight months. I just wanted you to comment on the above measurements that whether they suggest a problem in the battery or not. Thank you so much.

On January 31, 2013 at 7:15am
Chris C. wrote:

Man, I sometimes wish I was already retired and could respond timely to these interesting posts! “Cousin John” has been so helpful and insightful, it’s been a real delight following this conversation! (If you have German ancestry like myself, you’ll know what I mean, John smile

I would concur with John and from your second set of measurements that indeed, there seems to be nothing wrong with your battery, as Total voltage - Final voltage gives corrected figures for the first cell consistent with a negligible difference between each, indicating good balance.

In any case I would still insist that you do not neglect cell equalization, as your inverter charger setup doesn’t seem to provide for it, as it has been my experience over the years with this type of battery that it is, after forgetting to keep the battery charged when not in use, the most common cause of battery failure, with one cell eventually irreversibly sulphating from being chronically undercharged, or drying up and oxidizing from gassing out.

On January 31, 2013 at 5:51pm
John Fetter wrote:

Chris C. - Your last paragraph points directly at the root of over 90% of all reported problems with lead-acid batteries. Undercharging.
The electrical systems in automobiles are primitive. Almost as if deliberately designed to ruin batteries ASAP. Most battery chargers are designed by electrical/ electronics experts who have a seriously inadequate understanding of the principles of the lead-acid system. (I am one, so I should know.)
Incredibly, they do not appreciate the importance of voltage.
It should be easy for manufacturers to fit adaptive voltage control, that takes battery usage into account. Give you an example. Some cars are regularly driven short distances, others all day long. The regulator should have a memory, so that it “knows” how the car is driven. When the distances are short, the voltage should be increased. The voltage should be decreased when the car is driven all day.
Same applies to boats, aircraft, trucks, etc.

On February 1, 2013 at 3:29am
Khurram wrote:

Thanks Guys i think i got your point, all your trying to say is that i should buy a smart charger which has sufficient range of voltage adjustments at lest up to 16V for equalization and maintenance of the battery in general.

On February 1, 2013 at 1:46pm
Chris C. wrote:

Khurram, that’s pretty much it wink

To be successful, manual equalization using high voltage must be attempted only after the battery received its full charge in the normal manner, otherwise it will result in very high currents which could destroy the battery from warpage and corrosion.

I use a conventional manual charger with mutiple taps for that. I’ve gotten excellent results going as high as 17V, with only 1 to 2 A going into the battery, for a total energy absorption of 30 watts or so, which is minimal at our temperatures.

Of course, don’t forget to check electrolyte levels because most of this energy is going to end up as heat and decomposing water by electrolysis and only a small fraction being actually absorbed by the weak cell.

On February 1, 2013 at 1:59pm
Chris C. wrote:

John, right on. We just lost my mother’s car battery, after only two months of non use (and forgetting to bring the charger when I’d come for a visit wink). Not surprising as she’s been using her car less and less and only for short errands. 10 minutes runs at 14.4V once a week just isn’t enough to keep a battery in good shape!

On February 6, 2013 at 6:23pm
Tony E wrote:

Really interesting threads here…thanks folks…

Maybe I’m really coming at this from left field, but as a biochemist I couldn’t help thinking more physically about pulsing desulfation, and conversely the causes of sulfation.  Could it be that sulfation and the ability of reversing sulfation is more simply related to how the crystals were formed, what types of crystals are formed, etc? 

Obviously, keeping the battery fully charged seems to extend the life of the battery.  Is that because there are no short term chemical conditions to form crystals?

Does using a battery more often create less stratified layers due to ongoing magneto-hydro-dynamic conditions (i.e. constant stirring), so that the crystals formed are more uniform and can therefore be dissolved back into solution more evenly, and possibly avoid the formation of larger crystals which are harder to dissolve - or if these larger crystals are semi-permanent they may combine with other leftover “crap” which results in something with even lower solubility?  We might want to look at that sludge in the bottom, separate it and run it through some spectroscopy to see what it’s made out of.

Could pulsing desulfation be related to getting a physical current moving (stirring),  like how a propeller in ice water will help dissolve larger crystals or inhibit / reduce formation of ice?

Is this maybe why adding additives may contribute to some reduction in sulfation?  Like when you add salt to water, it lowers the freezing point (crystal formation), and below that temperature you will see salt precipitate out of solution as ice forms…etc?

A really interesting experiment would be to constantly stir the battery cells and compare with a control.  I wonder what they used in space at zero gravity beside flywheels.

Just some food for thought.

Tony E


On February 7, 2013 at 2:20am
John Fetter wrote:

Tony E. - A few comments to help make the discussion more interesting:
The concept of pulsing in the context of desulfation was invented and patented by Carl Edward Gali, ex-Texas Instruments, aimed at solar powered batteries. It is a concept with obvious instantaneous appeal to entrepreneurs. I believe products were designed, manufactured and explanations worked out, in that order.
Why wait for a plant to die before watering, a dog to starve to death before feeding?
Lead sulfate is almost totally insoluble in battery acid. Solubility varies, averages 2- 4 ppm.
Lead-acid reactions rely on the mobility of lead “adions” or “adatoms” across the surfaces of the active materials of the plates.
It is doubtful whether lead adions/ adatoms would respond differently to pulsing or plain charging.
Agitation, pumping, etc of the electrolyte is in use, in particular, in submarines. It helps but not much.
Logic suggests that if pulsing works better than charging, the sulfation problem must involve high resistance paths, not big crystals.
Additives do not reduce sulfation directly, they improve conductivity inside the plates.
I would suggest that implying that charging extends the life of a battery is analogous to suggesting that eating extends the lives of animals.
Simply having a starter-type lead-acid battery fully charged for perhaps 2-10% of its life, reasonably regularly, obviates sulfation. If that is not possible, caveat emptor.

On February 8, 2013 at 12:06pm
Tony E wrote:

Thanks for your comments John, a pleasure to have such a succinct response…and I’m more about seeing if there are other explanations than the “snake oil types” and have no skin in this game on whether I’m correct or not…and also to be fair here, I am a relative lightweight in this subject, but sometimes a probe/comment from another direction, besides inorganic chemistry (no disrespect intended) may be useful (if not only to me…  smile
So I’ll bite here…assuming as you surmise, that “Logic suggests that if pulsing works better than charging, the sulfation problem must involve high resistance paths, not big crystals.”
I would first reply with “Well, big is relative” on the atomic versus molecular scales.  If an interactive surface is cluttered with malformed crystals or chemical entities or layers, or layers + sludge, or whatever happens close to the reaction site, as occurs in numerous biological mechanisms (sulfation occurs biologically in a number of mechanisms – but maybe it’s too loosely a use of the term sulfation), could the nature of the clutter suggest the weird (non-uniform) chemical catalytic and non-catalytic reactions that are occurring near or at the reaction site…rarely is a reaction surface truly flat like a sheet of graphene, etc and in the case of modern batteries, the plates are porous grids, no?  So, really we start with a bunch of tunnels where there are a myriad of local conditions with varying local chemistry, some more efficient than others.
At the reaction sites, could we have crystalline/sulfation artifact tunnels or spongy like environments where micro hyper chemical activity occurs, that overall seem like high resistance paths but locally are something quite different? I.e. we don’t just have reaction sites coated uniformly in sulfation artifacts. These micro worlds conceivably could be pulsed with short bursts of electricity, resulting in hyper activity that could disrupt or change the micro environment surrounding the reaction surfaces.  It is conceivable that electrical bursts (maybe resulting in magneto-hydro-dynamic outcomes), harmonic shaking of the micro environments, stirring, electrolyte changes and temperature changes, etc., could all play different roles in the nature of the micro environment surrounding the reaction surfaces. As opposed to charging, where less drastic micro environment changes might occur.  I would then see charging as more status quo in the microenvironment and pulsing as more disruptive, possibly allowing the micro environment to “reset” somewhat.
On the next point, you state that “Additives do not reduce sulfation directly; they improve conductivity inside the plates”.  I assume you intended this comment and didn’t mean to say …additives improve conductivity between the plates and the electrolyte…  If that’s what you intended, then I assume that the additives penetrate the porous plates and change their ability to pass around electrons, etc.  But then again, I suggest that these additives would also change the playing field at the reaction surfaces, since in order to affect conductivity of the plates, the additive would need to be sequestered somehow and integrated with the reaction surface resulting in additional, possibly more complex local outcomes at the reaction surface.
More food for thought.

On February 9, 2013 at 12:35am
John Fetter wrote:

Tony E. - It appears there may be two ways to look at the situation.
(1) Study the “offending” component and work out what has happened using the best techniques at one’s disposal.
(2) Have look at how a battery begins its life, run an experimental cell in a glass jar.
Thousands of people have had a go at (1). For the purpose of this discussion, I propose to have a go at (2).
I managed to get hold of a variety of unformed lead-acid batteries. Simply tore them down and carefully extracted the plates. The active material in the positives is usually a light orange-brown, the negatives a light gray.
Use one positive, one negative, build into a glass or acrylic jar. Add acid and begin formation.
A little bit of background information. All the text books I have consulted say that around 50% of the active material in the plates does not contribute towards the actual measurable electrochemical functioning of the battery. In other words, it sits there, appears to do nothing.
Formation is the first charge. It consumes 350% ampere-hours. The discharge that follows delivers 100% ampere-hours and the second charge consumes around 110% to 130% ampere-hours. Thereafter the battery delivers 100%, consumes 110-130%.
It is very instructive to look at the plates while they are being formed. They change color. The positive goes very dark brown, the negative dark gray.
The changing in color begins at the grids, grows into the active material. The process is not uniform. Some areas seem to form before others. It is very obvious that the spreading of conductivity plays a major role.
What is abundantly clear is that a huge surplus of ampere-hours is “pumped” into the cell on that first charge.
I believe the explanation is simple. All of the active material is charged on that first charge, only a portion of the active material can be discharged. The portion that underlies the surface layers cannot be discharged.
As long as a battery spends most of its working life in a satisfactory state of charge, the underlying material provides electronic conduction. When the battery is habitually undercharged, the underlying material becomes sulfated. The resistance rises and the battery no longer wants to accept charge.
Apply pulsing and the high resistance path is overcome and the battery begins to accept charge. If the battery is totally sulfated, pulsing can only bring back the active material located nearest the grid structure.
If cadmium is used as an additive in a 100% sulfated cell, it is possible to see it electroplating onto the negative grids, spreading very slightly into the sulfated active material. Color changes. Repeatedly switching charger on and off and the growth can be seen coming and going - each time penetrating farther into the active material, until the negative is restored. The positives do not suffer permanent sulfation. Simple charging restores them.
You can draw your own conclusions.

On February 9, 2013 at 7:22am
John Fetter wrote:

CONTINUED The behavior of supposedly insoluble lead at a sub-nanometer scale at the highly convoluted electrode surfaces is totally different to its behavior in bulk electrolyte. It is roughly three orders of magnitude more active than a minimum required to sustain lead-acid battery reactions. This implies that larger lead sulfate crystals take proportionally longer to be whittled down compared to smaller crystals. It does not predict irreversibility. Charging causes lead sulfate crystals to dissolve away and lead dioxide crystals to grow adjacent, in the positives; lead metal crystals to grow adjacent, in the negatives. This is promoted by pushing up the cell voltage using a charger.
Everything happens very, very near the surfaces. Suggestions that lead sulfate crystals can be made to dissolve into the electrolyte appear to be the product of fertile imaginations. They can, of course, be removed permanently with EDTA.

On February 18, 2013 at 8:59am
Bryan Stamm wrote:

This thread thas been very interesting.  I would like to take it in a slightly different direction.
I have 2 “deep cycle” group 24 batteries in my RV bank.  I removed them, and recharged.  In order to test them, I applied a 20 amp load (inverter + 120 voltm, 250 watt bulb) to one battery.  After 25 minutes, the voltage dropped below 10.5 volts, and the light went out.  Obviously not a “new battery” as these are rated for 140 min reserve, and apprx 80 amp-hr.  Rather than throw them away, I tried the “dump the electrolite / fill with distilled, charge, dump, and fill with electrolite method.  I increased the run time to over 100 minutes.  The only Issue I have now is the electolite SG.  It reads “dead” on a 4 floating ball hydrometer, but still puts out 12.6 volts at rest, and last for > 60 minutes to 11.0 volts (I didn’t want to drop it to 10.5 volts).  This is very wierd.  Can anyone explain why the battery charges normally, seems to have decent capacity, but the electrolite SG is too low.

I dumped the “dead” electrolitte from the fully charged battery and installed new electrolite.  Same results.

On February 18, 2013 at 10:31am
John Fetter wrote:

Bryan Stamm - Dumping the electrolyte and filling with water simply creates more problems. Your battery plates and your battery electrolyte are now out of synchronization. I personally would have put the battery on a very long, very slow charge.
Your battery now has two problems. You need to get rid of the one you created. You must replace the electrolyte at the right time of the cycle. Put the battery on a very long, very slow charge. Then, when the battery is as fully charged as possible, dump the electrolyte and put in new at 1.280 SG.
If there is any life left, the battery will respond.
Some people would recommend pulse charging instead of a very long, very slow charge. I have found out pulsing does not always work, (like CPR on a dead person).
No one can give any realistic guarantee regarding these remedies. I will not attempt to try to give you an explanation regarding your observations.

On February 18, 2013 at 12:24pm
Bryan Stamm wrote:

“Then, when the battery is as fully charged as possible, dump the electrolyte and put in new at 1.280 SG. “

I did that, twice.

I expected there SG to be greater than 1.3, not < 1.15. 
Where is all the H2SO4 going? 
What are the voltage / run times still ok?

On February 18, 2013 at 3:25pm
John Fetter wrote:

Bryan Stamm - The additional info about replacing the acid twice and still getting nowhere with the SG implies your battery situation is not of a technical nature.

On February 18, 2013 at 9:56pm
Bryan Stamm wrote:

I am not sure how to interpret “not of a technical nature”.  Can you explain?  The battery acid that was added was brand new, with a 1.3 SG out of the box.  I am using a Optima 1200 charger.

On February 21, 2013 at 1:56pm
Albert wrote:

John Fetter - I read this whole page in awe and amazement.Now about cadmium I quote you “One level teaspoon cadmium oxide per 60 Ah cell” so am I right in saying that for a supposedly 12V 60Ah lead acid battery I would need “six level teaspoons” one for each cell? Just wanted to be clear and precise on your recipe.

On February 21, 2013 at 2:59pm
John Fetter wrote:

Albert - Yes. you can add much more if you want fast recovery but then you need to fully charge, then wait a day or two, drain the acid and replace with fresh acid. This gets rid of all the excess cadmium. You can use cadmium sulfate for quicker results.
I am not in this line of business. I work with industrial batteries. I prefer to keep batteries in tip-top condition, add booster to the battery while it is in good condition, improves battery life dramatically. I don’t use cadmium for this. I am not promoting cadmium. I just happened to have tried it on 100% sulfated plates, found that with plenty of patience, it works.

On February 22, 2013 at 10:36am
Albert wrote:

John Fetter - When you say full charge you mean uninterrupted or on and off as you stated earlier? Clarify please.

On February 22, 2013 at 4:21pm
John Fetter wrote:

Albert - After charging, waiting, charging, etc., make the last a good long charge - wait a day or two without charging, (the longer, the better), the cadmium will redissolve out of the negative plates, drain the electrolyte to take out the cadmium, replace with fresh acid. This prevents dendrites and possible shorting later.

On March 5, 2013 at 3:45pm
Nate wrote:

Great discussion. Hope you don’t mind some more prosaic questions..  Love knowing the “why” of the answers (and retail battery tech’s oft don’t know).
1) I have a generator which starts via a 12v closed cell lead-acid battery. In Chicago winters are cold so I bring the battery inside. Is this a wise or needless work?
2) My multi-meter says the battery now has a 12.65v charge. Today I heard 2 opinions: (a) sulfation begins at 12.45v and (b) it begins at 12.68v. Is either correct?
3) I am planning to purchase a NOCO battery charger (3.5 A). What do you recommend as a “proper” charge to balance sulfation and grid corrosion—perhaps 14v?
4) Reading the posts above I understand under-charging creates sulfation. But, let me ask this: I understand I can have the battery charger on constantly for the 4 months the battery is inside. I would prefer to charge it to say 14 and allow it to naturally discharge to say 13v over a month. And then to charge it to 14v again. Is this an inferior approach?
Thanks much.

On March 5, 2013 at 4:44pm
Jack wrote:


First, what type of battery are you using?

With a good quality AGM battery, leaving it outside in the winter fully charged is the best thing you could do for it. The cold significantly reduces self discharge and extends battery life. A good quality AGM battery will still deliver strong cranking in cold temperatures as well but not as good as when warm.

Even for a standard flooded battery it will last longer if kept cold, on the other hand its self discharge will dictate that you need to charge it during the winter on a periodic basis. In addition, you may loose critical cramping capability.

Sulfation is not based on voltage so much as acid concentration, it generally starts to happen at about 75% state of charge and accelerates below 50% state of charge in most lead acid batteries.

I took a quick look at the Noco chargers .. seems like a quality product with the usual loads of crap marketing BS thrown in. You don’t seem to have much control with the 3.5 on charge voltage though.

Given you are not going to be charging/ discharging on continuous basis (right?), then plate corrosion is not so much an issue if the charger properly terminates.

The Noco seems to have a warm/cold setting, but unless it actively detects temperature and compensates (not as easy as it sounds as batteries have thermal mass too), then the cold setting is only a bit better than no setting depending on how cold the battery is.

In terms of a proper charge voltage, some AGM batteries suggest 14.2-14.5, some suggest 14.5-14.9 ...flooded/GEL more in the 14.1 range. Given you are not going to be charging that often I would not worry that much about a few hundred millivolts over as you will get less sulfation. If you were continuously cycling I would be concerned due to electrolyte loss/corrosion but you are not.

Keep in mind with a cold battery, you may need to charge with as high as 16V, so if you are bringing the battery inside only for charging, let is stabilize for 24 hours so the proper charge voltages are used.

If the charger has a proper float charge mode, usually about 13.2 - 13.8 battery tech dependent, then you can leave the charger on without any issue.

FYI, though the charger is at 14V, the resting voltage of the battery after charging is more like 13V and will decline to say 12.6-12.7 before being recharged.

On March 6, 2013 at 12:48am
John Fetter wrote:

Nate - Your generator almost certainly has an AGM or gel battery, both of which are unhappy compromises.
Sealed lead acid is designed for ultra low water loss, definitely not for long life and must use oxygen recombination. This process is easily overwhelmed, so the charge voltage is limited. However, if you limit the top of charge voltage of any lead acid battery, the negative plates will become sulfated.
I would normally leave a battery out in the cold but suspect Chicago cold will freeze your battery. Sulfation is caused by undercharging. There are additional factors that can make it worse. Sorry Jack.
If you are measuring 12.65V, your battery is happy.
I personally prefer to use a taper charger that can push a fully charged battery to at least 16V. Use a timer. Switch on, charge, switch off, once a week. Set the ON period just long enough for the battery to reach 15.3V. As soon as it hits 15.3, switch off.
There are thousands of experts that will give you hundreds of different opinions. I suspect this is what attracts certain types of people to this kind of technology.

On March 6, 2013 at 6:30am
Jack wrote:

Hey John, no arguments at all on the 12.65V meaning the battery is good. Even with typical cheap multimeter accuracy issues (0.5%), that still puts you over 12.58 which puts you at about 80% SOC or so with a new battery.

I like your suggestion of tapered charge for a brief recharge weekly, but I am not sure your suggested implementation is realistic for the casual user (i.e. Timer, etc.)

Depending on the quality of the user’s battery, and if it is AGM, since it is being kept fully charged, I am not super concerned about it freezing, even in Chicago. Chicago’s on the lake and even when the lake is frozen, you get some moderation though the lowest ever was -33C, and the lowest continuous was -24C over a day. If it is not AGM, I would be bringing it inside.

Nate, I am not sure what your mounting options are, but leaving the battery outside, but putting it into an insulated contained may be your best option. Lead Acid batteries have a lot of thermal mass, but over the period of a night, uninsulated they will reach the low ambient temperature. With adequate insulation, they will stay much closer to the average daily temperature.

On an aside John, I remember an NREL study on spiral would AGM, they were topping out at almost 17 with intelligent tapered charge to ensure no sulfation. They had a fairly intelligent algorithm. That said, I have seen some fairly significant gassing at 15.5 from my telco Genesis AGM batteries at this voltage. Flat plate do not seem to take the voltage abuse (using the term lightly) of the spiral wound. I have had a hard time entertaining discussions with some of the major flate plate deep cycle AGM suppliers about high voltage tapered charging ... they like to stick to the Fixed CC/CV it seems. Any comments?

f you start fully charged though, and just touch 15.3 that should be good. However, I am not aware of a charger that will do this automatically for Nate in a cyclic manner?  Can you suggest one?  I am not disagreeing with your suggestions, more concerned with the practicalities of your implementation. Perhaps just a good and proper full charge followed by a continuous temperature compensated float charge would be easiest?

On March 6, 2013 at 3:54pm
John Fetter wrote:

Jack - Hardware stores sell plug-in timers that are commonly used for lamps. The old fashioned taper chargers work the best for this application.
The problem with AGM and gel is that their designs are compromises. They are not good in deep cycling, although they are often sold as such. Manufacturers will quote CC/CV figures, knowing full well they are not likely to provide long battery life.
There is a fine line between undercharging a battery and overcharging. There is no optimum plateau. The only way to maximize battery life is to take the battery well into gassing briefly, from time to time.
I realize it is not always easy to run batteries properly. One should try anyway.

On March 8, 2013 at 5:33pm
Nate wrote:

Thanks so much for the responses Jack and John!  Very helpful and very appreciated. Sorry for my response delay.
First, here is my specific battery info:

Vision CP12180XRP, Briggs & Stratton 193463GS Battery Specifications:
Chemistry:  Sealed Lead Acid
Voltage: 12 volts
Nominal Capacity: 18Ah
Terminals: Insert, Reverse Polarity
Dimensions (L x W x H): 7.13 x 3.03 x 6.57
Weight (pounds): 12.6
Additionally, the Noco tech advised me their charger will charge flooded batteries to 14.4 v and then stop based on battery resistance. (Sounds like this is well below what is needed for even brief gassing to occur).

Unfortunately, the generator’s design leaves zero room for any battery insulation—though the entire unit is modestly covered. Fortunately, in 35 years there has never been a winter power outage. But the generator is wired to the furnace . And it would need to start. That is why I brought the battery inside.
The timed taper charger idea is excellent ( to extend the battery’s life (which is the objective) but practically is difficult for me to do.
Also, it appears desirable to leave the battery outside—assuming I have it on a float charge.(And if it stays fully charged, it will likely not freeze even at -15 which it certainly can drop to).  But my situation also makes running an extension cord outside to enable the battery to constantly float charge impractical.  [Or, given my inability to insulate, do you still think charging it say once a month would be sufficient? While I do not know the battery’s natural discharge rate,  I am afraid I would need to charge it weekly—and I could miss that schedule and then have a compromised battery].
It is a real pain to remove the battery from the generator. But bringing it inside allows me to ensure it stays fully charged—if I needed it in the dead of winter. I will reconnect it from April-November.
So, there are some practical constraints that prevent me from doing all you suggest. But is what I am doing a reasonable Plan B: (a) bringing the battery inside (b) fully charging it (c) allowing it to naturally discharge for about a month and then (d) bringing it back up to a full charge again ? I would do this maybe 3x over the course of a winter. Or, will this plan significantly reduce battery life?
I am very open to purchasing a different charger that you may recommend. Thank you for looking at the Norco. It seemed reasonable (though its maximum charge will be 14.4 per the tech).
Also, since my battery is registering 12.65v, should I still charge it (after I purchase a charger)? Or is it as “happy” as it should be?
Finally, a tech told me today that sulfation does not begin until a 12v battery reaches 10V. This does not seem factual. Your comment above says bad things begin at about 75% of SOC (which is about 15.75v) or 11.8v. Am I thinking about this correctly?
Thank you again guys.


On March 10, 2013 at 4:35pm
John Fetter wrote:

Nate - If you’re happy to bring the battery inside in winter, only put it back in the generator when you need it,  it all becomes dead easy. Give it a good charge. Keep it in the coolest spot in the house, no charger, just as is. If you anticipate a problem with the power, give the battery a boost. Otherwise give the battery a boost once a month, approx. If you forget for a month, does not matter, the battery will retain plenty of charge.
Battery voltage is not a reliable indicator of a battery’s ability to deliver starting current. After three years I would test the battery by connecting a lamp that consumes one or two amps to discharge, measure amps and time. If you find it does not come close to the rating on the label, replace the battery.
Battery voltage does not predict sulfation. Sulfation is caused by undercharging. Batteries are always either undercharged or overcharged. It is impossible to find a “sweet spot”. That is how lead-acid works. The secret to long battery life is to deliberately overcharge, just a touch. This means taking the voltage over 14.4 occasionally.

On March 10, 2013 at 6:37pm
Nate wrote:

Thanks John. I will do all as you suggest.
Im not “happy” to bring the battery in—but I think it may be the most workable solution for me.

On March 11, 2013 at 3:04pm
Khurram wrote:

Hello Guys,
I have a question that when a tester is connected to the negative terminal of a battery, when inverter is also attached with battery then the tester light should glow? as i have tested it and it does. However, everyone knows that this is not the case in AC but is it different in DC? I also connected multi-meter’s negative probe with the negative terminal of inverter+battery and positive probe of meter with the ground and the voltage reading was 85V. Does DC behaves this way? This should be case when checking the positive terminal not negative.

On March 11, 2013 at 4:03pm
Chris C. wrote:

Isn’t there a warning label saying something like “danger lethal voltages may be present” and to not touch the connectors? In any case it would indicate the charger is probably pushing constant current like those used for tool batteries.

As for safety it would be dangerous when disconnected with no load, once connected and charging it would droop to safe levels.

On March 13, 2013 at 3:00am
khurram wrote:

An electrician who also makes and sells UPS told me that ur inverter is giving ground to the battery, i do not believe him however, i checked it my self and need your input on this. I used screw driver tester, which he also used, and when i connected it to negative terminal of the inverter+battery, it glows as bright as it does when connecting it with positive terminal of inverter+battery. (Dial used on DMM was 200V DC)
Then i connected the negative probe of multi-meter with negative terminal of inverter, when it was charging the battery, and positive terminal of DMM with iron bracket on the wall nearby and it showed 81.6V. Then i connected negative probe of DMM with positive terminal of inverter and connected it with iron bracket on wall and it showed 70.6V. Now the thing is that there should be more volts going into positive terminal of battery instead of negative. As far as the screw driver thing is concerned, it glows bright on both terminals when inverter is either charging the battery, discharging it or even after the termination of charging. however, when inverter is tuned off and its input is removed from wall power plug then tester never glows.
NOTE= (As we all normally check the reading on both terminals of inverter+battery was 13.7 V, when it was charging. DMM is 99% accurate). In fact used another DMM as well.
Need your inputs, Many thanks.

On March 13, 2013 at 3:04am
Khurram wrote:

I checked the vent caps of the battery and there was a slight black powder like stuff inside the vent caps. Does this means that battery is being overcharged?

On March 23, 2013 at 10:55am
Wil wrote:

What causes sulfation?
When a battery is discharged, sulfation starts, right?  So is “insufficient voltage”  a cause of sulfation?

If say I have a 12 volt car battery (lead acid of course) and it starts to read 10.5 volts, I’m guessing sulfation is already occurring at this voltage…..
but what if I connect the battery in parallel to a 12 volt DC source like a DC adaptor.  Will sulfation halt while the battery is connected to the 12 volt DC source?

On April 4, 2013 at 4:02pm
John 2 wrote:

Hello John Fetter, may I ask you a question? (and to everyone else who is knowledgeable about the subject.) I have acquired a solar power system and I live in a place where lead-acid batteries are the only available option. You said above that these are not suitable for solar systems because they would run all the time partially discharged. Is this always true, independently of the ratio between the generated power and the capacity of the battery? The system generates 160 W for a nominal tension of 12 V, so this would provide a charging current of over 10 A. The batteries available here have around 75 AH. So I would suppose it would be possible to fully charge the battery on two consecutive sunny days, provided that no power is drawn from the battery during this time. Or does this not work when charging is interrupted during the night? Or is there something else I am missing? - After a full charge, I suppose it would also be possible to maintain the battery by not discharging it to under 50%, so it could be fully charged again on a single sunny day. Or am I completely off track with my thoughts? What other recommendations could you give for the case where there is no alternative to lead-acid batteries?
I am sorry if I am asking dumb questions, but I am only just beginning to inform myself about the characteristics of batteries, and I do not even own a car, so I am quite unfamiliar with everything related to this subject.

On April 4, 2013 at 4:17pm
Jack wrote:

John 2,

Yes absolutely you can use lead acid batteries with solar. This is done day in and day out with great success.

However, you can’t take the simplistic view of your battery being charged after 2 “sunny days”. A sunny day is not a sunny day is not a sunny day. They we have to look at panel mounting ... i.e. is it fixed, which changes how much sun you will collect at a given point of the year.

What you need to look at is how much battery capacity you will need worst case over a period of time, say a week, and ensure that your battery will be able to support that without going into a deep discharge situation (and consider the battery aging and being cold).

Then you need to look at worst case solar production as you may not have a sunny day for weeks on end and if you MUST use the system, this must be taken into account.

Recommendations are to over size the solar panel .... especially since they are really cheap these days, and to buy a good charge controller that can be set to properly charge your batteries (Morningstar comes to mind).

Rarely will that 160W panel put out 10amps (or even close) unless you plan to continuously move the panel and have an MPPT charge controller.

What type of battery you use will depend on how you intend to use it. If you are in a position to regularly maintain the battery, then a high quality flooded deep cycle can be best. You can overcharge these a bit and add water to compensate which prevents sulfation.

If you are not in a position to maintain it regularly, then a good quality AGM deep cycle can be used. These can take a bit of “overcharging” as well to prevent sulfation.

Batteries will always “start’ to sulfate at partial state of charge. What is critical is to ensure on a regular basis (in a cycling application) that the battery is fully charged (with a bit extra). Hence a good charge controller and over sizing the solar.

On April 4, 2013 at 7:16pm
Chris C. wrote:

The problem with lead acid batteries is that they need to be maintained at the highest possible voltage to minimize sulfation.

As Jack wrote, this means an oversized system and batteries that can take an overcharge, because equalizing is an essential part of the charging process and this requires overcharge with distilled water replenishing of the cells that will gas out in the process.

In my experience with marine troll type batteries (which are built a bit like automotive batteries but with coarser, heavier plates), has been that they can take some heavy discharge to 0% and even lower as long as they don’t stay more than a day or so in this deeply undercharged condition. On the other hand, I’ve managed to get my batteries once all the way down to 2V over a couple of days (forgotten load) and it took me 3 weeks of charging, discharging and equalizing to get them back to snuff, but they were never the same after that.

It sums up to this: the longer a battery stays in a discharged condition, even a partial one, the more it will sulfate and the cumulative effects will eventually add up and cause the battery to fail.

If you have access to more than the standard deep-discharge batteries found in stores and sold for marine use, I would suggest, if you need to have a reliable power source, to look into industrial single cell battery systems of the type used for standby power by telephone companies, like the Surettes, the advantage being, it’s easier to build a balanced battery this way, and bad cells can be taken out without the need to scrap a whole battery.

On April 5, 2013 at 12:45am
John Fetter wrote:

John 2 - The users of solar can probably be divided into two groups - a tiny minority who have a full appreciation of all the nuances of lead-acid and a majority who do not.
Lead-acid will not last in solar unless it is periodically overcharged. The minority of solar users understand this, the majority do not.
It appears that if the user is conscious of the fact that the batteries must be overcharged occasionally and willing to do what is necessary, lead-acid is the perfect solar battery. If not, it is not.
Thousands of desulfation devices are sold every month (1) to people who do not take proper care of their lead-acid batteries. These devices are sold by people who claim sulfation is a normal process in lead-acid. Sulfation is caused (2) by inadequate charging. A high percentage of commercial battery charging equipment (3) is designed by people who do not have a proper understanding of lead-acid technology.
Cycle your batteries according to demand. Give your lead-acid battery a controlled overcharge when you can but not less frequently than once a month. Use flooded batteries. The batteries will last for many, many years. If you want maintenance free, be prepared to buy many, many batteries, be prepared to spend a small fortune.
I do not want to go into specific numbers because then the discussion will never end.
There are many people whose incomes depend on selling MORE batteries. There are many opinions on this subject. Caveat emptor.

On April 5, 2013 at 11:30am
John 2 wrote:

I am using a charge controller which automatically cuts off the charge current when the battery reaches 14.4 V. This value is hardwired in the controller and cannot be changed; so I suppose this makes a “controlled overcharge” impossible? (Except if I bypass the controller and keep charging for some time at noon when power is highest?)

On April 5, 2013 at 12:25pm
Chris C. wrote:

Indeed. This is how most chargers are set up. The problem with that is if one cell is undercharged, it may not get enough voltage to prevent it from sulphating and bring down the whole battery.

Overcharging for equalizing is a delicate matter because you need high voltage, but you need fairly low current to prevent overheating damage.

For a ‘standard’ sized 100AH battery, you can safely go with up to 2A at 20 volts, as long as the battery doesn’t get too hot (try not to exceed 45C). This is certainly feasible with solar cells, I have a few that output just over 24V at rest.

If your setup produces 10 amps in full sun, charging only one battery may be too much. 20V at 2A is 40 watts input; considering most cells would be bubbling off and only those cells which require equalizing would actually be taking the charge, most of it would be turned into heat, which you want to avoid as much as possible.

Go ahead and try, but do monitor voltage, current, electrolyte level and temperature.

On April 5, 2013 at 12:53pm
Jack wrote:

WOW ... slow down.

20V is well beyond what you should ever need for a bit of over charge to prevent sulfation and realistically, your battery should “cap” you out well below that at 2amps unless there is something wrong. We are talking serious overcharge at that point.

I agree in principle with John Fetter w.r.t. flooded batteries, but that is not always possible and for unattended solar installations it is just not an option. That said, I know well treated (i.e. proper charger, load, sizing, etc.) solar systems running on good AGM batteries (Concorde) are seeing 5+ years of service.

John 2, it would be good to tell us what you intend to do with this system.

Simply cutting off the charge current at 14.4V is a fine recipe for sulfation. At a minimum, it should be holding the end of charge voltage until the charge current reduces to a low value. Ideally it has an equalization mode for flooded, conditioning mode for AGM, etc. that engages on a regular basis. You are not going to find that in cheap chargers though. 

The cheapest charger I would recommend would be the Morningstar Sunsaver. It has proper 14.4V absorption charge and a 14.9V equalization. Some would recommend higher, but that is better than nothing. The Sunsaver MPPT is another good option. Don’t quote me on this as I don’t have one here now, but I think you may be able to control the equalization. You can on their larger units, i..e TSMPPT, but these are not cheap.

The other issue with cheap chargers is there temperature compensation. Some really cheap ones do not have it and even the ones that do don’t do it well. If you plan to have this outdoors, if you don’t have temp compensation and it gets cold where you are, consider the batteries toast after the first winter as they will never charge properly.

On April 5, 2013 at 3:53pm
John Fetter wrote:

John 2 - It would seem you correctly identified the elephant in the room. Simply bypass the controller. I would select a suitable resistor to limit the current to 2A max at full sunlight. Ordinary filament lamps in suitable series-parallel combination make a good resistor. Chris C is correct about the 20V, but you don’t charge at 20V but charge from a source capable of delivering 20V but limited to 2A. This is also known as constant current charging.

On April 6, 2013 at 10:26pm
Jack wrote:

John 2.

What is your intended usage?

Generally people who are doing small solar are doing it for “low maintenance”, Is it going to be practical for you to disconnect the main charge controller, disconnect the panel, connect the panel up to something that limits current, reconnect, ensure you only run it for a set period of time ..... of course doing that when the battery is already fully charged (which is not easy to determine) and when you have full sun, etc?

There is actually a simpler way of implementing a basic equalization with a cheap charge controller. This can be done by switching in a schottky diode between the ground of the controller and the ground of the battery. A schottky diode (properly chosen) will have a forward voltage of about 0.5 volts. You could use a regular diode and get a forward voltage of 0.7volts.  What this will do is raise the charge voltage from 14.4 to 14.9 (or 15.1). Given your charger just cuts off, going for the higher voltage may be better.

This is a high enough voltage to cause some gassing, but not so high you need to worry about overheating as the charge current will drop as the battery charges.

When you know the battery is fully charged (and you have a sunny day), you could switch the diode in and let it charge normally for 3 or 4 hours.

With this method you don’t have to worry about resistor selection (and your panel voltage will change a lot with light level and with temperature) and it is universal across all battery sizes whereas current limit varies by battery size.

On April 7, 2013 at 12:06am
John Fetter wrote:

Jack - I believe there is no need to disconnect anything. Simply connect the resistor via a switch to bypass the controller. The controller has voltage feedback control. With the resistor in, the controller senses a high battery voltage, turns off the charge current, leaving only the resistor doing all the charging. No need to fiddle inside the charger. Brightly lit up lamps would confirm the boost charge is working.
I should have mentioned that an isolation diode might be needed in series with the resistor.
People who come to this website surely are the type that figured out that no technology is perfect, no technology can work unattended and that “maintenance-free” is a selling point, never a technological reality?.
John 2, you now have multiple choice.

On April 10, 2013 at 11:20am
John 2 wrote:

Thank you very much everybody for your kind help. So I will see what I can do.
I am using the solar system at home for providing power for a laptop which is in very frequent use, and some other appliances which can be connected directly to 12V DC, and for bridging interruptions in the power supply from the grid (which are rather frequent where I live) via a power inverter to 220V AC. I had also thought of changing the lighting of our house to 12V DC bulbs and connecting them directly to the solar system, but now I think that would not be a good idea because it would draw all the power from the battery, and it would be better to use the solar system for appliances which require power during daytime, and at night only if power supply from the grid fails. - Anyway, the battery is indoors, so it is safe from extreme temperatures.

As for the mounting of the panels, they are fixed in east-west direction, so there is no way of orienting them towards the sun in early morning or late afternoon; but they can be inclined in north-south direction according to the season, so they have always optimal exposure to the sun at noon. Judging from our power consumption, the panels produce more than one kWh on a sunny day. I live in the Andean highlands where sun radiation is quite intense. We have almost every day several sunny hours, even during the rainy season; and during the dry season we have practically cloudless sky during four months of the year. If there should be no sunny weather for a week or so, we can still switch to grid energy - it is not very reliable here, but at least it can help to save battery power when it is available.

On April 10, 2013 at 4:20pm
John Fetter wrote:

John 2 - The fact that your solar is a backup to a 220V AC grid supply simplifies everything. You can use a PLAIN transformer-rectifier 12V car battery charger to equalize your solar battery. Leave it permanently connected to the battery. These types of chargers will take the battery volts right up to brisk gassing. You can use a timer switch, with internal battery backup, to automatically switch on once a week at approx maximum solar output, to provide perfect equalizing, without even having to think about it. Moreover, if you have no sun but you have your grid supply, you can still charge your batteries.

On April 10, 2013 at 8:17pm
Chris C. wrote:

Indeed, if you have grid power it’s a simple matter of using a plain manual charger consisting of a simple transformer and rectifier sized for your battery system so that its current output will be around c/50 to c/100 at 15 to 16V.

The beauty of the old style grid powered chargers is their inherent self regulation, as the sine wave output causes current to reach zero at maximum voltage.

Granted, finding old style manual chargers may not be so easy as they are being superseded with the new generation of fast, powerful and compact chargers that are driven by sophisticated electronics, but that is exactly what you should be looking for in your case.

In any case, monitor current (keep it low), the battery temperature (less than 45C ) and check your electrolyte level. It’s not high voltage that kills batteries during overcharge, it’s high current, heat and water outgassing.

On April 19, 2013 at 4:49pm
Robert H. wrote:

Thanks Mr. Buchmann.

It’s very gracious of you to share such a wealth of knowledge that must have taken many years and much study and experience to acquire. 

Lead acid batteries are my largest interest right now, and from my point of view - I’ve bought different types of smart chargers, standard chargers, float chargers, pulsers, and chemicals - all in an effort to learn how to recover weak starting and deep cycle lead-acid batteries. Your willingness to share your knowledge has allowed me to actually recover some weaker batteries that otherwise would have been turned in for core; some have actually been remarkably recovered to almost 100% of their labeled CCA with great load test achievements.  Your knowledge has also allowed for me to understand how to recognize batteries that are prone to be in the earliest stages of failure and bring them into, and maintain them in, proper functioning condition.  Just as valuable is the knowledge you share that keeps me from expecting miracles from fad chemicals and chargers and thus knowing how to evaluate an SLA battery to determine if it’s a waste of time to even work on it. 

Thus, you’ve not only saved me quite a bit of money and time, but you’ve given me the intangible gift of knowledge, and you don’t even know me. 

Again, Thank You!

On April 19, 2013 at 5:13pm
Robert H. wrote:

Thanks to John Fetter and Chris C. as well.  Lots of knowledge you gentlemen bring to the table in discussion; I’ve read and learned from much of it. 

My level of expertise (on batteries) and electricity: Novice for sure smile

On June 14, 2013 at 12:00pm
Chuck P wrote:


I am a maintenance Tech for a grocery distribution center. We use 24 volt and 36 volt batteries for our forklifts. As part of my maintenance I water the batteries if they had been charged the night before every Friday.
John Fetter mentioned “A high percentage of commercial battery charging equipment (3) is designed by people who do not have a proper understanding of lead-acid technology.”
Which got me to thinking I have no idea what my charger is doing to my batteries. My battery rep tells me to hit the equalize button once a month which I can assume is the same as an overcharge.
How can I tell if I have a properly designed Charger?
should i note the amps on the display during a charge?

Anyway what originally brought me to this interesting conversation is that I was visited by a battery rejuvenation vendor and they are selling battery desulfater devices to be attached to my forklift batteries.  Only understanding the basics of the sales pitch I smile and nodded till they left. so with a fist of brochures I did some research
This is the company that came to visit me.
This is the source of the battery tender desulfaters
( the owner of battlife also owns Jaxian)

I was interested most in the little device that attaches to the battery says it slows down the sulfation process. They said poor maintenance is the main reason for batteries building up sulfide.  They seem to specialize in bringing near dead batteries back to life using this pulse technology and bringing dead batteries back to near full capacity. But I am unique in that this is a new facility all my batteries are only 6 months old. I want to keep them in top condition. What guidelines should I follow?
If i can maintain watering and charging procedures and assuming I can determine I have a decent charger, would this device be beneficial?

Thank you for taking the time.

On July 25, 2013 at 10:25pm
denise wrote:

Hello gentlemen.
I have read this thread and several of the tutorials with great interest. I have shared what I have learned with my dad who is fascinated. My dad has installed a solar system with a battery bank and we have been trying to figure out how to maintain the batteries effectively.  Please excuse this humble request for basic information including recommended tools—hydrometer, type of battery charger and exactly how to equalize the battery bank, and how to de-sulfate batteries or can any one direct me to a source where I can find that step by step information? Thanks!

On July 25, 2013 at 11:34pm
John Fetter wrote:

denise - It’s easy. Keep the batteries charged as much as possible, discharged as little as possible. Keep them watered. Don’t believe people who go on and on about sulfation. That’s about it.

Chuck P - Get a voltmeter. Forklift batteries must be charged to at least 2.55V per cell. They will sit at a lower voltage for about 90% of the charge. Right at the end the voltage rises. Measure just before the charger is due to switch off. People who go on and on about sulfation have a product to sell.

On August 6, 2013 at 1:52pm
denise wrote:

thank you for responding.  a voltmeter?  is a hydrometer also useful? are they used in conjunction? is there any other efficient, accurate way to test the batteries?

On August 6, 2013 at 7:09pm
Chris C. wrote:

The voltmeter gives a general reading for the whole battery;  a hydrometer allows you to check each cell’s chemistry and determine actual cell charge level.

In other words, voltage is the most basic of tools but doesn’‘t give you a full picture as batteries are made of cells connected in series (6 for a 12V battery). You could have a battery with decent voltage that actually has a bum cell in the series, a voltmeter would not be able to tell you, but a hydrometer would.

If one of the cells has low electrolyte density it runs the risk of sulfating and essetuialy killing the battery. Hence the importance of equalizing, which consists in overcharging the battery so that the poor cell will get the charge it needs, and adding distilled/deionzed water to the cells that are already charged as required,  as overcharging basically boils water by electrolysis.

In the end, all the cells will become even in density and you will get the best performance out of your battery, you may even save a battery that could have gone bad. Remember, once a cell is sulphated, the whole battery is basically a write-off. So, you see, a hydrometer is an essential tool for getting the most out of a battery.

A thrd tool you may want to get is a load tester. This essentially applies a known load on a battery to simulate the effects of a car stater and measuring the voltage drop. From that, internal battery resistance can be calculated and cranking current can be derived.

On August 6, 2013 at 7:51pm
denise wrote:

thank chris c that was extremely helpful and clear! can i get a load tester at a car supplies store ? more importantly,  what is the best way to over charge a battery bank? do you take one battery off at a time and over charge it or is there a way to over charge a battery bank? and is there any thing that needs to be avoided or done in order to be efficient and avoid something dramatic from happening like say an explosion? : 0
thanks again,

On September 25, 2013 at 11:29am
Arthur Schultz wrote:

I read all of the above comments, which are most helpful. I hope someone can clarify my own situation.

I have a commercial fishing boat. Unlike the overwhelming majority of fishing vessels, which have engines constantly running, I rely very heavily on battery power. I anchor for long periods and use electric jigging machines. My intermittent charging and steady battery drain resembles an off grid home installation more than it resembles a typical industrial use.

Among our small jigging fleet batteries and alternators are constant topics of discussion. We’re moving to fancy external regulators that supposedly give a better charging profile than standard regulators by boosting voltage, and using temperature compensation. Alternator based charging could occupy its own year long conversation thread, but that’s not my current issue.

I have four 8D style 12V batteries, and I got the best “special purpose” deep cycle batteries that are available from my local NAPA store. They aren’t quite the same thing as a Trojan industrial battery, but they are a few steps beyond the “starting/deep cycle” batteries that aren’t really deep cycle. I cannot always charge the batteries completely because there are many times when I run the engine only briefly while moving or searching for fish. Idling doesn’t do much for battery charging or fuel economy, so I don’t do that much for charging purposes.

My batteries have been settling to a voltage around 12.5V after 12 to 24 hours. I’ve had the opportunity to completely isolate them to check resting voltage. I just ran the boat for several days while traveling, manually forcing a number of charge cycles to ensure a full charge, and checking specific gravity with a refractometer after a day’s rest.

With a presumed full charge, the voltage settled at 12.5V and my readings ranged from 1.260 to 1.280 among the 12 cells that I checked on a paired bank. I’m a bit confused by this reading. Above I read that a starting battery should be fully charged at that specific gravity. I also read that some deep cycle batteries might have a specific gravity of up to 1.33 to wring the max out of the battery. Could my batteries really only be partially charged—and I suppose partially sulfated—at such a high specific gravity?

On September 25, 2013 at 5:07pm
John Fetter wrote:

An ideal way to find out what condition batteries are in is to first bring them more or less to a full state of charge. No need to be precise about this.
Next put them on a constant current charge of C/20. This is also called an equalizing charge.
Try to bring the cells up to about 2.6 volts. As long as the voltage continues to rise, keep charging. When it stops rising, stop charging. Individual cell voltages are unlikely to be the same. The battery will gas briskly and will become hot. Leave standing overnight and the next day measure the cell SGs. The readings represent true full state of charge for each cell. The SGs will not be identical.

On September 29, 2013 at 12:09pm
William L. Benson wrote:

I would like to put a de-sulfator on my battery bank.  But the de-sulfator works by putting a pulses across the batteries which I need way to block these pulses from the inverter.

I live off the power grid and I am using 24 fork lift batteries connected to Trace SW5548 converter with a 10KW generator.  The converter is sensitive to voltage spikes kick from the battery cable inductance when the cable are to far apart.  These spikes will damage the input filter capacitors!
NOTE: http://www.xantrex.com/documents/Discontinued-Products/SW2512MC-SW4024MC2UserGuide.pdf page 110 of the manual!

On September 29, 2013 at 2:55pm
John Fetter wrote:

William - People who purchase desulfation products are the desulfation product salesman’s lawful prey. They are the battery equivalent of beauty products. Work if you believe they work. All you need to do to keep your batteries healthy is to bring them to full state of charge and gassing at intervals. Called an equalizing charge.

On October 14, 2013 at 7:04pm
shawn kelly wrote:

RE: high Frequency ultrasonic excitation….I do claim that this form of excitation prevents sulfation, not removes once the damage is done, but prevents the actually root cause.  first we should establish what everyone thinks sulfation means….it may not be what you think.  for starters one must consider the ionic flux differences between Pb and SO4(HSO4) ions at the electrode-electrolyte interface….and we should keep it simple by only discussing flooded type chemistry.  Once Isee interest i will attempt to explain the pyshiochmeical effects and believe me it is frequency (waveform) dependent….we swept from 300Khz-9Mhz during our testing phase….

On October 14, 2013 at 11:03pm
John Fetter wrote:

shawn - It looks like you are trying to lay a bet without putting your money on the table.

On October 15, 2013 at 12:04am
shawn kelly wrote:

John….in lead acid - 2 successful proof of concept test, 1failed (equiment failure, but learned a lot), in li ion 1 I test underway.  10+ years going after this technology and I do not consider it a bet.  I like to think that I understand this phenomena better based on this effort.  In the first test we cycled the cells between 2.04 and 1.7VDC, control was not mechnically excited and test cell was excited (@3.2Mhz)....the biggest obvious and noticeable difference was the test cell cycled 3 times to every 2 times the control cell did.  We also did not see obvious signs of cyclic degradation on vibrating cell as we witnessed on control cell.  We did not understand these results thoroughly until after comparing to follwo on CV testing

On October 15, 2013 at 1:41am
John Fetter wrote:

shawn - Why do you mention Li-ion? You say you are cycling cells between 2.04 and 1.7 volts. What kind of cells? If the cells are lead-acid, you’re not cycling, you are permanently discharging. Your information is very confusing.

On October 15, 2013 at 3:39am
shawn kelly wrote:

John…I apologize for the confusion….‘prematurely discharging’, i am not completely sure I understand this term?  The test cell (i.e. 3 cycles) did discharge 1/3 less energy through out 8000 minute test than control cell (i.e. 2cycles).  Both cells were discharged through an equivalent and constant resistive load.  Cells were COTS VLA batteries sold at Walmart.  After first 4000 minutes, all the electronics used for test and control cycling were swapped to ensure this difference was not induced by test set-up then the test commenced for 4000 more minutes.  Part way through the second 4000 munutes the non-vibrating cell (control) showed signs of significant degradationand would no longer switch from charge to discharge.  Yes, this has been difficult to explain 1) why vibrating cell discharged less energy throughout test, 2) why it cycled 3 to every 2 cycles under same voltage plateaus.

On October 15, 2013 at 4:19am
John Fetter wrote:

shawn - I am not sure how you managed to misread “permanently” and interpret it as “prematurely”. I do not think you have anything special because you appear not to be operating the batteries properly. A voltage of 2.04 is a below-fully-charged value.

On October 15, 2013 at 4:28am
shawn kelly wrote:

John, the cell discharged until it reached an OCV of 1.7VDC and then it charged until its OCV reached 2.04VDC.  Thus, it discharged and charged, over and over again, cycle after cycle.  Permanently discharging a battery makes no sense

On October 15, 2013 at 4:43am
John Fetter wrote:

shawn - Open circuit values are useless in the context of cycling.

On October 15, 2013 at 4:52am
shawn kelly wrote:

John….we just used OCV for switching action.  I could send you the test report and we can start over….we have not evem got out of the gate

On October 15, 2013 at 5:19am
Chuck P wrote:

Well Shawn I would have to agree with John F. It sounds like your trying to sell something.  The line about what causes sulfation and it might not be what we think. Classic ad man lingo. And considering you never followed up on it with any facts. Just to consider the ionic flux differences of lead and acid. There are 7 paragraphs at the beginning of this that explain what sulfation is, If you have imperical evidence that contradicts or improves this information, how about you tell us what it is. Or do we have to send you $19.95 for a phamphlet explaining it to us?

On October 15, 2013 at 5:33am
shawn kelly wrote:

it is not surprising i have not put all the facts behind these claims….if interested i will send my first test results

On October 15, 2013 at 5:41am
shawn kelly wrote:

Meaning I just started this post last night.  Too anyone interested I can send test reports or you can review my 14 page article in the fall 11 addition of Battery and Energy Storage (BEST) magazine

On October 15, 2013 at 5:42am
John Fetter wrote:

shawn - You opened the discussion by asking other people to show an interest. Very little progress can be made until you provide a description of the test procedure that other people can understand. There have been thousands of claims over the years. So you need to figure out a way to clearly demonstrate your claim is credible.
If you go to the USPTO website and read the patents on this subject, it soon becomes obvious from the background information provided in each specification that each inventor, in turn, believed that he triumphed over all the others.
You must figure out how to conquer that formidable obstacle.

On October 15, 2013 at 5:47am
John Fetter wrote:

Battery and Energy Storage (BEST) articles are not available on line. The magazine is not available over the counter.

On October 15, 2013 at 6:37am
Chuck P wrote:

OH the articles are available on line, for 50 UK pounds for a year subscription.
@Shawn So now you want my e-mail address so you can spam me with crap?
So you acknowledge you haven’t put up all the facts of your claims. How about you Actually put up the facts of your claims, right here right now.

On October 15, 2013 at 6:58am
John Fetter wrote:

I found the Summer issue of BEST on line - no Fall issue. Shawn, I’m sorry but your presentation did not come across very well.

On October 15, 2013 at 11:10am
Arthur Schultz wrote:

I just finished equalizing my batteries for the first time. I did not quite follow the instructions posted above on Sept. 25, but I sure did get them to outgas vigorously. Several issues arose that have not been touched yet in this already lengthy discussion.

I bought a variable DC power supply, a Volteq HY3020EX. I believe my 8D batteries are 180 amp hour units (not so easy to learn this from NAPA) so a C/20 current would be 9 amps. The power supply doesn’t have the best documentation, but it’s easy enough to get some power out of it. I quickly hit a dilemma. I’m told above to push a C/20 current, but I’ve also read that I should equalize around 15.8V max.

I set my power at 15.8V and over a few minutes the current went from around 10A to 2A. there was some bubbling but not what I’d call vigorous. Since this power supply can adjust either voltage or current, I cranked the current up to 5.3A and the voltage rose and settled on 16.3V. This made the outgassing fairly vigorous. I would compare it to a freshly poured glass of ginger ale with lots of tiny fizz and also a steady number of larger bubbles. I did this for four hours on each of my four batteries.

During this procedure the liquid in each cell seemed to turn opaque, partly from bubbles but also the liquid seemed to have a gray-brown tint. I think lead sulfate is the same gray-brown color. Is that right? Should the acid have turned a muddy color? The batteries are in dark and confined spaces so I was stuck examining them by flashlight while being a bit contorted. Thus I’m not 100% sure of the opacity or color rendition. All I can say is that I don’t think a glass of ginger ale would have looked brown in that light.

My puzzlement over the correct amp and volt settings led to a point that I had forgotten to consider before. What is the effect of temperature on this whole process? I have read many times that the batteries would get hot. I live in a climate where a warm summer day may hit 65° and I equalized from an initial temp in the mid 40s. I probably outgassed 2-3 oz of water from each cell, but the batteries certainly did not get hot. They never felt warm, so the temperature probably stayed under 70°. I know that electrical resistance rises with temperature, but chemical reactions also tend to go faster as temperature rises. I figured that the batteries needed more voltage because they were cold, but I have never seen any guidelines on equalizing cold batteries. Should I have used more power than 5 amps and 16.3 volts?

Now that I’m done I see some slight difference. The sp gravity has risen from about 1.265 to 1.270 or slightly more. The batteries seem to return to the expected resting voltage faster after turning off a load. I could zap them some more. How do I determine whether I should?

On October 15, 2013 at 4:21pm
John Fetter wrote:

US Patent 7,592,094 to Shawn Kelly, Sept 22, 2009, 280 claims. US Patent Publication 2010 0021798, continuation of US Pat 7,592,094. The patents do not introduce anything radically new. The specifications are critical of a large number of prior art inventions, include long rambling discussions and are remarkably short on specifics relating to the actual invention itself. The patents are classic, designed to attract investors.

On October 15, 2013 at 4:53pm
shawn kelly wrote:

John, its not a continuation…i served 21 years in the US Navy….11 Years on submarines of which reached the highest qualifications possible.  I am now a Product Manager for the largest Commercial Nuclear Power Plant in the world….and have over 11 I&C products (radiation, nuetron flux and vibration control &  monitoring systems).  You obviously have no idea what you are reading, you clearly are not so smart in IP space. 

At any rate, I like your completely cynical and speculative nature.  You likely have no clue where the energy storage industry is going as a whole, and that’s why you are not grabbing the intrinsic and well thought out claim set, or did you read them….i bet you don’t even know how to determine what an independent claim is if a patent only had two claims.  Nothing radically new?????  Please you are not qualified

On October 15, 2013 at 4:59pm
shawn kelly wrote:

All, John seems to be a very selective and narrow filter and he does not want to learn something he does not know because he knows it all. He is making false claims, not myself.  I have not even been able to have a decent technical discussion based on his blog hazing. 

If anyone would like to discuss the effects of high frequency mechanical excitation on lead acid chemistry performance and cycle life that would be great. 

John, why don’t you take a break.  I am not trying to sell anything I am actually trying to get help solving a very real problem in the industry, but it takes background to get people up to speed and you have done nothing but babbled yourself

On October 15, 2013 at 5:01pm
shawn kelly wrote:

It is Autumn 2011 BEST issue, not FALL

On October 15, 2013 at 5:41pm
John Fetter wrote:

shawn -  Thank you for that.

On October 15, 2013 at 5:42pm
Chuck p wrote:

You work at the Kashiwazaki-Kariwa plant? Thats cool. Alright enough of the righteous indignation. Lets get to some science. Ok, so as a battery sits unused this is the worst thing for a battery.  Sulfation begins. So what your saying is that by generating a frequency pulse inside a battery anywhere from 300KHz - 9mhz but i believe 3.2Mhz was the number you mentioned for the test of lead acid.  Now with 3.2 Mhz frequency going through one battery and not on another battery. During 8000 minutes of discharge and charge cycling that the frequrncy battery recharged it self more times than non-frequency battery.  3 cycles freq to every 2 cycles non freq. so isince it was the same load or discharge rate. Does this mean it was charging faster? Or was it discharging stronger was there heat difference in the load? Could it have discharging more? Was the frequency active for the entire 8000 minutes or just during discharge or just during charging?  Were the batteries taken apart to inspect the electrodes for sulfation on the plates?  Is there a way to measure the frequency penetration in the battery was it reaching all of the battery? If you were make your own battery of glass could you see sulafation and the nonsulfation of a frequency battery?

On October 15, 2013 at 6:21pm
Oscar Darwin wrote:

Shawn - Quite awhile back…I ceased viewing this web site as a source of objective research, study and information-sharing. Name-calling was just my first clue. The moderator says that, “Lead-acid chemistry is most definitely well understood”...but he then goes on to say he spent years researching to, “study the deepest inner workings of lead-acid batteries in some serious detail to find out what (his) treatment was doing right.” (meanwhile, he’s not interested in 40’s & 50’s-era research done by the US Military on battery sulfation) He says there are many pulse-charging patents, “...all written by inventors who describe their own version as correct and all previous versions as flawed. There is not one explanation that holds water.” You can see the same attitude in his responses to your posts as well. Later he says that in the course of his studying, “the deepest inner workings of lead-acid batteries”, he was able to, “figure out how pulsing worked.” So obviously HIS explanation is the only one that holds water. If you limit your research to the information found at this web site, you might think that lead/acid battery technology is only “well understood” if your experience aligns with the moderator’s. If your experience is different…then you’re just a rube or a “troll”.  ***But please take note that he’s not abundantly forthcoming with the information.*** In another post, the moderator says, “A bright young engineer in a battery factory would be ill-advised to go to his boss with a new idea on how to make batteries that last longer. Not a career enhancing thing to do.” But he then jumps on the bandwagon by ridiculing anything that doesn’t fit his ‘highly-educated’ template for extending battery life.
    The moderator (and many who comment here) rail against any form of de-sulfating chemistry or technology and scorn anyone who won’t share their formulas or research data. At the same time, the moderator boasts of spending $80K and “...years to develop and to test the material that can reduce water consumption and extend battery life.” But after this attempt to impress the easily-impressed, he then says, “I think you will agree there is no useful advantage to be gained by shouting out its identity.” So he won’t extend the same courtesy to others that he reserves for himself. He dismisses the research of others by pointing to the absence of their products on store shelves. Ask him what store shelves are displaying his product?? Can you say “double-standard”? Sure you can…I knew you could. Meanwhile, the moderator openly laments the fact that nobody wants to buy or discuss his ‘secret formula’. Were this an objective web-site for genuine exchange of ideas and research…I suspect others might be more forthcoming. But heck…even the battery manufacturers are extremely secretive about their own R&D. In order to make money, everyone is trying to protect their secrets. The moderator here is no different. He has an agenda. Everyone knows what the Chinese will do with a successful product. Patent rights mean nothing to them. Meanwhile, I’m making quite a bit of money de-sulfating large batteries and doubling their life in most cases…and my business is growing steadily. But anecdotal evidence means nothing here within the ‘scientific’ community. If you would like to contact me directly…please let me know. I’m working with an Asian supplier who has a product incorporating some of the latest technologies. (one of which is mentioned in a previous post here) I’ve been testing his product as well as his method for applying it. His business is growing rapidly. As a courtesy to others, I won’t be “shouting out its identity” since the moderator and pseudo-scientists here are invested elsewhere and will simply mock, scorn and engage in name-calling. Meanwhile…I’ll continue watching my bank account grow. Although they like to think so…I would advise caution in assuming that product knowledge begins and ends with the folks at this web site…or at the shores of the US. Cheers!!!

On October 15, 2013 at 6:32pm
Chris C. wrote:

Arthur, here are some pointers if I may.

1) Appearance: the brown comes from stirred-up mud, which is basically shed active material (lead oxide). The older the battery the more pronounced the effect. This bothers me a bit since you are not pushing that much current into the battery. It could indicate your batteries have significant wear. Active material tends to shed when it cycles especially when it gets overcharged or over discharged.

2) Temperature: 45C is pretty much the maximum temperature you want to tolerate so if the battery stayed cool it could indicate the current actually was absorbed which is a good thing.

3) Equalization: as the name implies, it is to make all cells chemically identical so as not to have a ‘weak link’ that could render your battery useless, as the cell with the lowest gravity will hold up all the others and reduce the battery’s capacity to produce power. 1.275 is pretty much the maximum you’ll get for this type of battery, but make sure they are all within that value +/-0.05

On October 15, 2013 at 9:33pm
shawn kelly wrote:

Chuck P. - now we are talking -
{No, I am a Product Design Manager (a domestic Plant equipment supply company) for our new and exciting Gen 3+ passive nuclear power plants. 

{Yes,...there are chemical reactions in equilibrium always….until it runs out of steam}  {I believe there is a worst case….and that is Float Charging at the wrong potentials and the effects on VLA and VRLA are similar but different….but regardless it does lead to failure modes for stationary battery applications}

{I read and understand the electrical pulse sulfating technologies; I also read and understand the older mechanical methods of performance and de-sulfating.  I do not believe sulfation is JUST PbSO4 hardening, I believe it is several Pb oxides (3BS and 4BS and maybe others) that come out of solution, based on ionic flux mismatches and the resultant alkalinity shift in that local region….these compunds interact with and bond with the very ionic PbSO4 salt, thus rendering this volume of ionic salt – defect ridden and not reversible.  So, as far as the electrical pulsing guys and others of similar vein and all this breaking of bonds once they are formed…..i am not at able to say they are wrong, I just know in order to convert this electrical energy to mechanical energy to break these unwanted bonds very high and destructive voltage and currents would be needed.}
{yes, the mechanical energy can be generated inside, it can come in externally, or it can be generated electrically with carefully selected anode, cathode, separator, or electrolyte material selection and fabrication if that material is mechanically responsive to an electromagnetic signal, i.e. ferroelectric, piezoelectric, electrostrictive, magnetostrictive, etc….  There are many, many ways to achieve the proper excitation….the key is in the application and the algorithum’s being used to maximize the effects.}

{Let’s just say that the frequency is selected to optimally interact with the physiochemical process for the chemistry of interest.  Meaning, I am testing Li-ion derivative as we speak and this frequency will be different for many reasons….including whether it has a solid or liquid electrolyte.  Clearly, it does not make sense to broad cast our frequencies all over the network.  We have also found that the amplitude and duty cycle of the waveform are very important as well.  Not to mention whether the device is on float charge, light or heavy discharge, type of charging profile, etc….  I am not trying to be elusive, however, every time I turn I am being thrown a curve ball with this science.  Yes, i understand mostly where we need to be for various situations, and the range is fairly given but the devil is in the details} 

Re:8000min and 3-2 cycles

{Yes, it discharged thru resistors of the same value.  Unfortunately, we did not measure current in the test so it made understanding the test difficult… During the very first discharge (both fully charged) the test cell released less energy (discharge time was shorter) while it went down to a 1.7VDC voltage cutoff level, mind you thru a constant restive load.  However, it continued to discharge less energy and therefore have to charge less energy through the entire 8000 minutes, we switched all the electronics and loads at 4000 minute point to ensure we were not inducing change (this did not effect performance).  This brought me back to the old peukert effect….something was making the vibrating cell discharge harder and therefore it was giving out less energy on the first discharge and this set it up for the remainder of the test.  However, everything other than the mechanical excitation was the same.  It was not until I compared it to my 2006 CV test before I started to understand what may have happen and how the mechanical energy (at ~3.2Mhz) was effecting the cell.  Let’s think about this and digest then i will present my conclusion}

{excellent question….unfortunately, we did not measure current and nor temperature on resistor.

{In this test through charge and discharge, however, there are many opportunities here in electronic design and energy cost space!}

{Yes, 10X magnification on control and test cells and the vibrating cell did not show any signs of discoloration of PbSO4 crystals…which are typically whitish….I have all these pictures in test report}

{Yes, these are problems already solved in other sciences….In this test no, in the 2006 CV test we know the mechanical energy was reaching all the active material surface area (a whole cm^2)

{ these are implementation problems (new and good problems we are dealing with).  I do believe under a 10X+ magnification you will be able to see distinct differences}

On October 15, 2013 at 9:35pm
shawn kelly wrote:

s h a w n {at} a c t i v e g r i d t e c h . {com}

On October 15, 2013 at 9:47pm
shawn kelly wrote:

When an ELECTRICAL pulse sulfator type can explain why they pick their frequency, rise time (with freguency components) and duty cycle and at which time to best apply during a battery system operating cycle….and it makes sense, is when I will believe.  I know they are getting effects, but they are certainly not optimal.  Meaning, anyone can pound energy (high frequency Voltages and Currents) into a battery and see some effects.  however, the adverse effects on the degradation of the battery based on these high and fast transient voltages and currents are detrimental to everything a battery is about….mainly its sustained performance and lifetime.  Yes, you are seeing some short term effects, however, the mass adoption of your techniques will not happen.  Your minimal short term effects are actually of a mechanical nature and the electrical-to-mechanical conversion efficiency is very low and therefore you are required by design to use very high and extreme amplitudes to get the minimal effect.  Your claims to remove PbSO4’s once they have been formed may be true, the problem is what ELSE are you removing or destroying as you do it.  You took the storage out of energy storage because of your ‘Brute’ force methods.  Again. what frequency, why this frequency and when?

On October 16, 2013 at 12:27am
John Fetter wrote:

shawn - Why are you here? Your co-inventor Joseph Galgana assigned his rights to you on June 6, 2011, then you assigned your rights to Ultrasonic Energy Efficiency Solutions, LLC, a Delaware corporation, on December 20, 2011. If it is as good as you say it is, there will by now have been millions pumped into the venture by retired technophiles. No need to come here and stride up and down the stage.

On October 16, 2013 at 4:35am
John Fetter wrote:

shawn - I managed to locate a copy of your article. It is very well written. It seems to be overweight in a way that users interpret battery technology. There is a heavy bias towards stationary batteries, predominantly used by large organizations, such as power stations, telecommunications, computers, internet services. Your project therefore requires massive investment, very difficult to secure.
The rest of the battery market reacts to the lowest price, not to technology.
The 3,000 to 20,000 magnifications I have seen of the morphology of the active materials imply that lead sulfate crystals form next to the lead dioxide and the lead crystals. The dissolution-precipitation mechanism is described by KJ Vetter in “Bedeutung der Loslichkeit von Electrodenmaterialen fur die Kinetik poroser Electroden”, Chem Ing Tech 1973, 45, PP 231-236. The lead moves between the crystal formations half in, half out of solution. It is very doubtful that the sulfate forms a layer over the underlying material. Fully sulfated negative plates I have seen are pitch black, not white.
Your high frequency wavelength selection to fit into the pores sounds like a good idea but how does it work?
Your way of communicating goes 1, 5, 7,9,10. Someone else tries to fill in 2, 3, 4, 6 and you call them stupid. That may be a reason why investors are staying away
I repeat, the text of your patent is classic trivial information overweight, critical information underweight.

On October 16, 2013 at 4:39am
shawn kelly wrote:

John…I came to this site to teach what I have learned and to hopefully help understand a specific failure modes for large stationary lead acid battery packs that are cycled long and deep.  As far as IP and companies, this is not something that is relevant but I will tell you I own the delaware LLC you spent time looking up.

On October 16, 2013 at 6:00am
Oscar Darwin wrote:

Shawn - You’re wasting your time. As I told you…this is NOT a web site for serious research, study and information-sharing. This is a web site where John Fetter gets to tell you why he’s such a genius while you’re just an idiot. It should be called the “John Fetter Ego-Stroking Web Site.” I guarantee you…you’re not going to teach John anything he doesn’t already know…because he already knows everything there is to know. Just ask him and he’ll tell you!!

On October 16, 2013 at 6:25am
shawn kelly wrote:

John, are you sure you were looking at a negative plate?  What did the positive plate look like? Clearly describing the PbSO4 as layer is very useful for illustrative purposes and it helps others….yes there are many different visions/studies/pictures of what it looks like….so I agree.  As far as half-in and half-out of solution I have read and heard this as well. Okay….the chemical environment (temperature, PH, surrounding reaction products, locality, etc…) and electric field gradients likely determines how much is in and how much is out of solution at any given time and point within electrode-electrolyte system….the main point is that it is very dynamic and it is constantly changing.  I tend to follow Dr. Pavlov and his team’s (Bulgaria) work over the last 3 decades and it has helped me understand the phenomena and physio-chemical process within the lead acid battery. Side note of interest….recently a team in Bulgaria applied ultrasonics to typical lead acid battery while it was undergoing formation charging and the result was 3-4X increased cycle life and improved performance (i.e. charge acceptance, capacity, lower impedance, etc…) and this has made me, my stakeholders and followers very excited,  I have also followed results of applying new SPM and various types of AFM’s measurement techniques to better understand both lead acid and li ion chemistry.  You would be surprised how much Li-ion interest my technology has received….

In my initial lead acid testing under magnification there were very distinct PbSO4 crystals that were whitish on the control cells surface, they were not visible on test (3.2Mhz) cells surface.  From Wikipedia -’...Lead(II) sulfate (British English sulphate) (PbSO4) is a white crystal or powder…’, but that is just Wikipedia.  Maybe you had visual of - Lead(IV) oxide, commonly called lead dioxide or plumbic oxide, is a chemical compound with the formula PbO2. It is an oxide where lead is in an oxidation state +4. It is an odorless dark-brown crystalline powder which is nearly insoluble in water….in its property chart it mentions dark-brown, blackish substance.  I do not need a lecture on, or need opinion on, use of wikipedia. 

I believe that as the PbSO4 crystal comes out of solution (half in or out) it sets up small micro pores (between the low micron level crystal boundaries) and this impedes the ionic fluxes (Pb, SO4 and HSO4) and this sets up adverse alkalinity conditions in which the conditions are favorable for Pb oxides, 3BS and maybe 4BS to precipitate out of solution. This is a very dynamic process and the severity and consequences are highly application specific.  As the potential on the electrode changes, lets consider and very fast step increase in potential, there is a large increase of positive Pb ion flux where it meets the electrolyte, the negative ionic flux can not keep up and the volume becomes positive.  however, we all know the law of ELECTRONEUTRALITY, so something has to change to make that volume neutral again. Well, that is when the potential, via electrolysis breaks up the H2O, and the positive H ions fly out of volume and the less energetic negative OH ions are left behind.  Therefore, that volumes PH goes up and this results in the bad, unwanted and highly irreversible tertiary compounds to come out of solution and interrupt the purer PbSO4 crystalline formation (which would have been whitish) but now is dark brownish or blackish.  Maybe that is the compound you witnessed?  In a perfect world the electrolyte would rewet that locality and those unwanted substances would go back into solution, but we all know it is not perfect world.  This is the process that degrades lead acid batteries performance and lifetime.

On October 16, 2013 at 6:34am
shawn kelly wrote:

Oscar….contact me

s h a w n {at} a c t i v e g r i d t e c h {dot} c o m

Clearly, john has locked out folks from sending emails so we have to be clever

On October 16, 2013 at 7:01am
John Fetter wrote:

shawn - If you had opened with your suggestions for large stationary lead-acid batteries that are deep cycled we would have been having a very productive discussion by now.
As you know, stationary batteries are not considered suitable for deep cycling and I would have suggested that you have a look at the details on the world’s largest lead-acid battery, a stationary battery that was, in fact, deep cycled its entire life. The 40 MWh Chino load-leveling battery with over eight thousand 3250 ampere-hour cells. The link is unesdoc.unesco.org/images/0009/000916/091670eo.pdf. You would have pointed out you have a better technology. Perfect.
Oscar Darwin wrote in on September 22 last year, immediately started breathing fire and brimstone at everyone who had the audacity to call his information outdated. A member of the AD-X2 club.

On October 16, 2013 at 7:33am
John Fetter wrote:

shawn - Our messages are crossing. I have described my experiments with sulfated plates on this website before. For ease of reference, I will give you a brief outline. I stored automobile battery plates vertically, free to move, in a bucket of battery acid for five years. Some cast grid, some expanded grid. Positives and negatives. When I examined the plates at T = +5 years they were black. Positives with a touch of brown, negatives pitch black. The cast grid plates were severely buckled towards the pasting side. The expanded grid plates far less so.
I used cadmium to help recover the negatives. It took three weeks. I managed to obtain nearly the full original ampere hours. The color of the recovered plates was medium gray.
I know about Prof Pavlov and his team. It seems they are among the handful of people still doing original research on lead-acid.

On October 16, 2013 at 7:38am
Oscar Darwin wrote:

What is AD-X2????  Whatever it is…I’ve never used it. However, if John Fetter belittles it…perhaps its something I should look into!! I think John regrets that he can’t re-write history. Anyone perusing these posts can clearly see the vitriol and angst he harbors toward any research that comes to a conclusion different from his own. The childish responses to visitors here speak volumes. He says my information was outdated. You can scroll back and see that I never really submitted much information. I did not do so because I was flamed by John & his toadies here before I had an opportunity. I quickly realized this was not a serious forum. The cretins here have no need of anything outside their miniscule echo chamber. Cheers.

On October 16, 2013 at 7:48am
shawn kelly wrote:

John, wjile they were vertically suspended in H2SO4 bath were they charged and discharged?

On October 16, 2013 at 9:17am
John Fetter wrote:

shawn - I received the plates, (about 15 A-h), unformed from a local battery manufacturer to use in my research. After forming, cycling them a few times, taking measurements, I put them into a large PE bucket, put the bucket in storage and did not touch anything for five years. The plates were loosely in electrical contact with each other. The plates were 100% submerged in battery acid all the time. I did this because there were so many theories flying around about sulfation, I figured I would be patient and make some genuinely 100% sulfated plates, then test them.
(We might have to shout a bit to be able to hear each other over the noise being made by Mr Oscar Darwin.)

On October 16, 2013 at 9:56am
shawn kelly wrote:

in your setup the resultant sulfate will be much different then if you actually replicated a real application.  I would not base any decision based on your test set up

On October 16, 2013 at 3:27pm
John Fetter wrote:

shawn - Thanks. That explains why you are here.

On October 16, 2013 at 4:15pm
shawn kelly wrote:

John….i think its time that you performed your mind boggling and foolish lead acid plate test on yourself… Hang upside down, in vertical mode, in a very dark and deep closet in your double-wide trailer, shut the door for 5 years.  In five years we will come and see what grew on you and what color you are.  Your test you alluded to proves nothing and the content on this site is unbelievably behind times.  I suggest you hang your hat and cut your losses

On October 16, 2013 at 4:45pm
Arthur Schultz wrote:

John’s plate test seems most relevant to me, and in fact is an ideal simulation. I’ve left my boat and its large battery bank for months on end in places where it could not stay on a float charge. Several long term storage events are almost certainly what killed the last battery bank. Three hours ago a friend lifted his own giant battery bank into a boatyard where the same situation is undoubtedly going to occur.

I’m in a situation that should be a poster child for battery abuse. My whole fishing group is seeing a phenomenon where interference slowly builds in our sensitive electronics. I believe the battery plates are slowly sulfating and causing an impedance problem that translates into fuzz on our fish finders. I just finished equalizing and a harbor test suggests that the interference is gone for now.

With these interference issues,who in his right mind would introduce a device that essentially makes the battery plates ring like high pitched gongs?

I’m seeing a senseless argument against a testing protocol that mimics the thing we’re all told makes sulfation. It also mimics real life problems. Put the suspect device beside the bucket and zap the experimental plates, because that’s the situation where I need to see some results.

On October 16, 2013 at 5:15pm
John Fetter wrote:

Shawn Kelly is operating a classic routine. I have seen others do this. It works on retired technophiles, gentlemen of means who enjoy technology and who believe they understand technology and have been persuaded by someone’s silver tongue that his invention is top notch and that they can profit by investing. I think an investor has pulled out. Shawn is hunting.

On October 16, 2013 at 6:12pm
shawn kelly wrote:

Arthur, do you know GM just decided to use LEAD ACID Chemistry for its new Hybrid Malibu?  I don’t think it was John’s test or his secret sauce that made that happen!  In fact, now that the root cause of the kinetic limitations in lead acid are better understood we are starting to see common sense, the bottom line, hit the main stream.  Li-ion performance at Lead acid cost

Okay….“John’s plate test seems most relevant to me, and in fact is an ideal simulation. I’ve left my boat and its large battery bank for months on end in places where it could not stay on a float charge”

{spk:  BTW: be very skeptical of your float charge….this also plays into deep discharge battery failure modes!  Did you completely isolate it from the electrical system of your boat? What was the state of charge when you left it on your island?  Not doubting this, just want to to shed some light on John’s non-sense and waste of life test In his test the electrodes discharged and used up all the ACID and the remaining 4.9996 years the plates were likely sitting in a warm bath tub of H20i}

“Several long term storage events are almost certainly what killed the last battery bank. Three hours ago a friend lifndted {what does this say!} his own giant battery bank into a boatyard where the same situation is undoubtedly going to occur.”

{spk: the problem with John’s test is that it does not replicate you or your friends situation.  His plates just discharged to a bath of H2SO4, of which we have no idea what the level of SG was, obviously not controlled.  John say’s sulfation happens anytime a battery is not completely charged and that it takes weeks for the PbSO4 crystals to reach its lowest stable state…i understand why he believes that. lfation only happens on negative plates and he did not answer key questions.  John also talks of sulfation and that it is black….well sulfation is apparently lower energy states of PbSO4 a known whitish substance, John says it is black? The physio-chemical process are on time frame of minutes, not weeks.  There are many studies and that measure the time frame for every reaction going on and how this impacts the open circuit voltage of battery - and how long it takes - and it is no where near weeks, it is minutes.  John is an extremely smart guy, but he is no different in my mind then the current Li-ion clowns, that find a new substance,additives or dopants, put it in the electrode material or electrrolyte, get great results in the lab, and then wonder why it blew up or caught on fire, three weeks after a monitored side-impact test.  John is of the same grain!} {of course John will come back with smack….and I already know what it will be ‘he already made reference to it unknowing what he was talking about}

I’m in a situation that should be a poster child for battery abuse. My whole fishing group is seeing a phenomenon where interference slowly builds in our sensitive electronics. {how big is your FISHING group, i bet you have a small one}

{interference builds in our sensitive electronics…what are you talking about? This means you suck at fishing nothing else….why try to convince you….follow Johns leaf}

On October 16, 2013 at 6:14pm
shawn kelly wrote:

John….you are comical and don’t worry….your science is safe!

Arthur, do you know GM just decided to use LEAD ACID Chemistry for its new Hybrid Malibu?  I don’t think it was John’s test or his secret sauce that made that happen!  In fact, now that the root cause of the kinetic limitations in lead acid are better understood we are starting to see common sense, the bottom line, hit the main stream.  Li-ion performance at Lead acid cost

Okay….“John’s plate test seems most relevant to me, and in fact is an ideal simulation. I’ve left my boat and its large battery bank for months on end in places where it could not stay on a float charge”

{spk:  BTW: be very skeptical of your float charge….this also plays into deep discharge battery failure modes!  Did you completely isolate it from the electrical system of your boat? What was the state of charge when you left it on your island?  Not doubting this, just want to to shed some light on John’s non-sense and waste of life test In his test the electrodes discharged and used up all the ACID and the remaining 4.9996 years the plates were likely sitting in a warm bath tub of H20i}

“Several long term storage events are almost certainly what killed the last battery bank. Three hours ago a friend lifndted {what does this say!} his own giant battery bank into a boatyard where the same situation is undoubtedly going to occur.”

{spk: the problem with John’s test is that it does not replicate you or your friends situation.  His plates just discharged to a bath of H2SO4, of which we have no idea what the level of SG was, obviously not controlled.  John say’s sulfation happens anytime a battery is not completely charged and that it takes weeks for the PbSO4 crystals to reach its lowest stable state…i understand why he believes that. lfation only happens on negative plates and he did not answer key questions.  John also talks of sulfation and that it is black….well sulfation is apparently lower energy states of PbSO4 a known whitish substance, John says it is black? The physio-chemical process are on time frame of minutes, not weeks.  There are many studies and that measure the time frame for every reaction going on and how this impacts the open circuit voltage of battery - and how long it takes - and it is no where near weeks, it is minutes.  John is an extremely smart guy, but he is no different in my mind then the current Li-ion clowns, that find a new substance,additives or dopants, put it in the electrode material or electrrolyte, get great results in the lab, and then wonder why it blew up or caught on fire, three weeks after a monitored side-impact test.  John is of the same grain!} {of course John will come back with smack….and I already know what it will be ‘he already made reference to it unknowing what he was talking about}

I’m in a situation that should be a poster child for battery abuse. My whole fishing group is seeing a phenomenon where interference slowly builds in our sensitive electronics. {how big is your FISHING group, i bet you have a small one}

{interference builds in our sensitive electronics…what are you talking about? This means you suck at fishing nothing else….why try to convince you….follow Johns leaf}

On October 16, 2013 at 6:30pm
shawn kelly wrote:

John…but as I stated, i like you….old school, but schooled

Shawn Kelly is operating a classic routine. I have seen others do this. It works on retired technophiles {john i thought you had spell check} , gentlemen of means who enjoy technology and who believe they understand technology {and of course you do} and have been persuaded by someone’s silver tongue that his invention is top notch and that they can profit by investing {the old silver tongue himself} . I think an investor has pulled out. {pleae GM has just made the move back to lead acid….in discussions I will bring up your secret sauce} Shawn is hunting {is PbSo4, a well known substance white or black????, please do your homework?}.

On October 16, 2013 at 7:08pm
shawn kelly wrote:

John Fetter has no patents of his own???  he is nothing but a patent troll running a web site blog and stealing everyone elses ideas. 

John if this is not true please list your patents and published applications

If you do not have a patent then you own nothing and your followers and hopefully not investors need to be aware of your agenda.  Who are you being paid by to run this site…..disclosure is warranted and if you do not decide to disclose we will initiate investigation based on the purposeful interference.

On October 16, 2013 at 10:45pm
Arthur Schultz wrote:

Chevy announced that is has killed its hybrid Li-ion Malibu in favor of a start/stop system that uses much small lead acid batteries to automatically start the engine whenever power is required.

Hmm. Already batting less than 1000.

I’m not sure how my float charge came up. Was I not clear enough? There is no charge, let alone a float charge. I’ve left my batteries to sulfate at will for months on end. This is ordinary in coastal Alaska. That is why John’s benign neglect experiment is so relevant. Were they fully charged to begin with? Who knows? All I know is that they did not freeze.

Did I miss something? Are we discussing crystalline growth or chemical reactions? Crystals form when the saturation state of a dissolved substance is high enough for them to form. Creation of a chemical compound is independent of its slow formation into a crystalline structure. This is one of the key points behind my skepticism of desulfator devices. It is activation energy, and not any sort of pinging at any frequency, that drives a chemical change.

I’m not sure how electrical interference makes me suck at fishing. It appears that equalizing may have removed the interference. I guess I don’t suck at it any more! Battery impedance is a well known source of certain types of interference, but typically it is due to corrosion or poor contact at the terminals.

On October 16, 2013 at 11:50pm
John Fetter wrote:

Arthur - I tried an experiment on an old fashioned antimony positive, calcium negative hybrid car battery to find out more about the relationship between self discharge and sulfation. I carefully balanced the self discharge rate with a pure constant current charge rate. The battery voltage followed the day-night and seasonal temperature changes. I adjusted the value of the constant current to keep the voltage swings centered on float charge. After about nine months the battery suddenly developed a “thirst” for extra current which kept getting worse. After a few weeks of this I decided to give the battery a boost to take it well into gassing. Then I went back to the same value constant current charging. The battery was back to where it had been before. This seemed to imply there is a buildup of something in the plates that causes the self discharge rate to go up. It seems like a good idea to periodically take a 12 volt battery to 15.5 - 16 volts.

On October 17, 2013 at 12:04am
John Fetter wrote:

shaun - The plates were in a discharged state. The acid level was way above the plates. The plates took in -SO4, the water evaporated, the acid concentration rose. I do possess a hydrometer.

On October 17, 2013 at 4:33pm
John Fetter wrote:

shaun - Can I ask you to explain how the acoustic energy gets to where it is needed inside a battery. I have reread your patent, US Pat 7,592,094. The entire acoustic propagation process upon which the invention is based appears to have been condensed into a single, technically inappropriate, although legally convenient word. According to the specification, the vibration is “telegraphed” to the matrix.

On October 17, 2013 at 4:41pm
shawn kelly wrote:

yeah…call me 413 579 7108

On October 17, 2013 at 5:36pm
John Fetter wrote:

shawn - Surely this is the appropriate forum?

On October 17, 2013 at 5:45pm
shawn kelly wrote:

John, now that you are asking HOW to get the high frequency mechanical energy to the right areas, it makes believe that you are going to derive a test?  We don’t have five years for this test, so please consider the market.

There are so many ways to get the mechanical energy to the areas it needs to get to

But we are way off your tooic

On October 18, 2013 at 12:19am
John Fetter wrote:

shawn - The reason why I asked is because there is NO EVIDENCE that your idea actually works. If you don’t want to explain, that is your decision.
I built some electronic equipment for a large international corporation that specializes in building power stations, many years ago. I have some insight into the ultrasonics used to test boiler tube welds. So I’ll have a go at explaining.
Ultrasonics need a clean transmission path. Even the tiniest imperfections scatter the energy all over the place, and quickly dissipate it
The ultrasonic waves will be projected by your devices vertically down the terminal posts and be reflected straight back up. The waves will be scattered by the metal surface imperfections and a small portion of the ultrasonic energy will bounce across the thickness of the top connecting bars and eventually into the grids. A tiny residual amount of energy meets the porous active material, the wavelength is small enough to enter the pores and the energy is immediately dissipated before it even touches the bulk of the active material. Some of the energy is conveyed via the electrolyte but is lost in the cacophony of standing waves caused by the billions of sub-microscopic active material surface to liquid interface irregularities of the active material. It is anyone’s guess how the energy can possibly reach the middle four cells in a 12 volt battery.
That seems rather complicated, so I figured that Jay Yablon, your patent attorney, condensed the explanation to “telegraphed”.
He is an interesting person. He is active in alternative science. He patents his own inventions. There is one for a telephone dialing system, US Pat 5,764,731. I can only guess that this concept was patented in anticipation of a fat telecoms corporation’s inadvertent use of the idea.

On October 18, 2013 at 2:19am
john wrote:

Could you two or three stop acting like children?

John you are not a battery god and Shawn to get respect you need to share more details.

On October 18, 2013 at 3:56am
John Fetter wrote:

john - I would suggest that the rules of civilized debate are straightforward. There are forums where everyone agrees with everyone else. This happens to be one where you can expect to have suspect ideas pulled apart. We should try keeping our expressions moderate. I would not call you a child but you chose to call me one. Shawn Kelly picked the ground. He has had every opportunity to back up his ideas.

On October 18, 2013 at 4:16pm
John Fetter wrote:

Oscar Darwin - Try being more objective. I am not the moderator. I am a visitor. I happen to like robust debate. Sulfation is a controversial subject. Ideal. Suggestion: Play the ball, not the man.

On October 21, 2013 at 5:48pm
Shawn Kelly wrote:

john, why don’t you read and digest this relatively old study

Influence of ultrasonic waves on the formation of lead-acid batteries V. Naidenov*, U. Markov
Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 10, Sofia 1113, Bulgaria

Then maybe an intelligent discussion will arise.  I would personally like to ask for your superior explanation of the increased cycle life. who knows maybe you do understand the Chemistry

On October 21, 2013 at 5:58pm
Shawn Kelly wrote:

John, you seem to have your own ideas on how ultrasonic energy get to where it needs to get.  that is great.  we already know a little about the transmissivity of high frequency ultrasonics through lead/lead alloy material and it is a very efficient process, contrary to your description.  this is a growing field with new techniques and materials surfacing everyday

On October 21, 2013 at 11:38pm
John Fetter wrote:

shawn - A person who will not undergo the difficulty of explaining must undergo the trial of being doubted.
The article to which you refer was published last year. The process of lead acid battery formation is very inefficient and very energy hungry. The investigators made it more efficient.
Your concept does not apply ultrasonics during formation. It is used on off-the-shelf batteries. You are the person promoting therefore you are under obligation to explain.
I have never doubted the ability of lead to conduct ultrasonics in the same way as I have never doubted the ability to copper to conduct electricity.
There is fog around this thing that grew thicker with your explanation about this being a growing field with new techniques and materials surfacing every day.

On October 22, 2013 at 5:56am
shawn kelly wrote:

John, not sure why you are qualified to say what my technology/concepts works on and does not work on and what time in life of battery it applies.  I showed you a completely independent test which stands on its own.  How many different chemical process are going on in formation vice field use, you seemed to be a bit confused

On October 22, 2013 at 6:16am
John Fetter wrote:

shawn - Of course I am not qualified. That is why I am asking you to explain how your ultrasonics do their work. It seems like a simple thing for you to do. I watched a video taken during one of your talks. Someone asked “how does it work” and you replied “efficiently”.

On October 22, 2013 at 4:43pm
shawn kelly wrote:

John, again you are repeating yourself (for good of self, community, or other), you are just at a loss for intelligent questions to ask based on what I already told you.  You are now not sure if PbSO4 crystals are WHITE or BLACK, in general you are clueless.

Why should I explain how it works AGAIN!. Do you seriously think my sales/licensing/future will come from your thoughts and this group think? I spent the best part of my 30’s and now my 40’s undoing your group think tactics. I hope some of your followers start thinking about batteries differently, I can only hope.  Sulfation is not magic, it is a simple result of inherent imbalances between the electrode and electrolyte that WE users set up, the harder we drive it the worse it gets.  AGT now has control.  These imbalances cause local alkalinity shifts making conditions for unwanted tertiary compounds to come out of solution more likely and this upsets the electrochemical conversion process and efficiencies, it is really that simple….not BLACK and not WHITE.

We ultrasonically manufacture and engineer an ordered network at the electrode-electrolyte interface which eliminates these inherent ionic kinetic inefficiencies and therefore substancially minimize these adverse effects.

On October 23, 2013 at 12:03am
John Fetter wrote:

shawn - Thank you. A search on-line revealed information suggesting that you have spent the last ten years trying to find investors to put money into your invention and have apparently not succeeded to any appreciable extent.
I found a video on-line showing one of your pitches to investors. You seemed to be selling the sizzle not the substance.
I have taken an invention from conception all the way through to a multi-million turnover business. It is difficult.
You absolutely have to make sure you understand how your invention works so that you can explain it to the people who you must first persuade to buy your product.
When you have a turnover worth speaking about you will have the kind of information that investors like to see. This is the only way you can secure ten or twenty million dollars of investment for your invention.
Would-be distributors want to actually see the invention in use and want to speak to the people who are using it.
I have looked everywhere to find a proper test report. I have not been able to find one. It would seem that you are still at the starting gate because of your over-abundant eloquence and under-represented technical prowess.

On October 24, 2013 at 2:04am
Chuck p wrote:

So could these frequency waves be adjusted to experiment on something more safe say keeping sugar in solution ?  Non scientist here.

On October 26, 2013 at 12:15am
John Fetter wrote:

Chuck - I heard that a hot cup of tea works. No need to go to the extra expense.

On October 26, 2013 at 11:03am
Adam Al wrote:

Hi, I’ve been reading your thread very carefully and been doing a lot of research on this topic. I have a new 150ah sealed calcium battery (solite) hooked up to my 120 watt solar panels. I’ve had the battery for around a month and now my battery will only charge at a rate of 8amps for around 6 hours then the charger will indicate a full battery and the volt reading will be about 13.3 BTW my charger cutts voltage charge at 14v . The voltage doesn’t drop when not in use it settles at around 13 volts. But the eye indicater on the battery indicates that the battery needs charging. Also on my load test the voltage dropped to around 12 immidiatly with a load of 7 amps. The battery voltage was 11.1 after roughly 6 hours of use around 40amps in total. Can someone pleas advise me what to do? BTW I have used a normal charger and I got the same results.

On October 26, 2013 at 8:11pm
shawn kelly wrote:

Adam, you are a victim and when i get my system in the market i will give you one, and you will no longer half to struggle with this.

On November 2, 2013 at 5:54pm
rustcity wrote:

Maximizing Deep Cycle Lead Acid Battery Life—Google “National Renewable Energy Lab, Optima Battery”, for instructive articles on how to increase typical deep cycle life by 200 to 400%.  The technique should work for lead acid batteries in general, not just Optimas.

Synopsis:  Measuring the total current charged, charge to the 0 delta Voltage and then charge an additional 10% of the total current, this last step being potential limited.

It is assumed the Voltage is at or above 10.5 V and that the battery has been in recent use. (Remember, never allow the Voltage to drop below this or expect the worst.) For a 50 Ah Yellow Top, charging can be fast, say 30 to 50 A, until reaching the Zero dV/dt, (Zereo Delta), point, at which reduce charging to 1 to 5 A and continue, charging an additional 3 to 5 Ah after reaching Zero Delta. New batteries may take 30 minutes for this last stage, while older batteries, 2 or 3 hours. This may extend battery life from 200 deep cycles to deep 500+ cycles. NOTE: This is a general charging guideline and it is the responsibility of the reader/ user to ensure safe operation at all times.

Re magic elixir additives, I have read many of the comments in this forum and found them enlightening.  I have found in the USA patent literature these seem to concentrate on trying to get what had been insoluble large lead sulfate crystals back into solution using a monovalent, Group I sulfate salt.  More additive is not better, with the most maxing out at less than 0.5 or 1.5 wt % of the electrolyte.  MgSO4 has also been mentioned frequently.  From here and other sources, it seems little benefit is to be gained from these if the battery lead was formulated properly for its designed use.  I.e., Ca for no maintenance, P for recoverable sulfation, et cetera.

Re Desulfators:  More costly desulfators are not necessarily any better than low cost ones.  I trialed a Power Systems desulfator that put out a clean square wave up to 20 A and up to 30 V that did little good on spiral wound AGM batteries and on large conventional flooded lead acid batteries.  Perhaps the batteries needed a different plate or grid chemistry.  On the flip side, I have used the rf, mA desulfator circuit on a low-cost charger with good success on some conventional batteries and no success on others.  A friend built a low-powered pulsing desulfator based on the most common circuit published on the Net with very good success on conventional batteries, given several weeks for the most heavily sulfated batteries.

Re who has what patents, a quickie search I found no patents by John since 1975, and one, on power recovery from tissue, (or something like that), by Shawn.  Apart from this, there are a lot patents that are pure baloney and a few that are pivotal.  Lots of worthwhile inventions are never patented and kept proprietary and many others are not simply because the invention is not the inventor’s center of attention.  As for Shawn citing his reference to the Bulgarian journal article, that is good, but is it accessible to us on the Net?

Re PbSO4 Fundamental Harmonic Frequency - I, too, would be interested in knowing both the electrical and mechanical.

On November 3, 2013 at 5:29am
John Fetter wrote:

rustcity - Or is it Larry? Carl Edward Gali received a patent for his lead-acid pulse desulfator invention in 1990. Next thing tens of thousands of enthusiasts were infringing. There may be a lesson in this.
For your ease of reference, go back to October 15, above. Patent No 7,592,094.
Credible scientific research into the Placebo Effect has shown that when told by a person of authority that a product works, about a third of people will report that it works even though it actually does not work. There may be people out there making a living from selling desulfation placebos.

On November 15, 2013 at 1:43am
Atrum wrote:

Hello John Fetter, I have been reading this page with fascination, its a gold mine of information. Before I read this page I made a circuit to revive a couple of Batteries which were in a state of low charge for too long a period. They were pulse type. But now I realise, it was perhaps not the best way to go. I have a question, which is a curious effect. I have a 12volt 96Ah battery that I revived. Now if I measure the voltage its 12.65 volts. If I apply a load 110 Watts (two bulbs) the voltage drops, and one of the cells begins to bubble. The light glow but are not bright. Then after 2 to 3 minutes the bubbling suddenly stops and the bulbs are at maximum intensity. very strange. Does this mean the cell that is bubbling has a broken link? If I remove the bulbs and reconnect after an hour the same occurs.

On November 15, 2013 at 2:36am
John Fetter wrote:

Atrum - I have no idea why your battery is doing this. There is bound to be someone with plenty of servicing experience who can explain.

On November 15, 2013 at 7:51am
Harry wrote:

Excellent and valuable information.
I have question on Reverse charging. I had a battery that was totally dead. It accepted no charge and even at 17 volts no current was registering on the amp meter. I had nothing to lose, so I reversed the poles on the power supply. Imediately the power supply was pushing out 2 amps. After 30 seconds I reconnected the poles to correct polarity, and the battery began accepting charge. I charged this battery very slowly over night and it held its charge. I am wondering what happened, did the reverse charging dislodge some of the built up sulphate, what caused the battery to accept charge? I am sure what I have done is not effective or correct way of maintaining a Lead Acid Battery but I am curious to know why it jolted it back to life.

On November 15, 2013 at 10:40am
John Fetter wrote:

Harry - Without knowing the history of the battery I think this is what I think happened. The boundary between the grid metal and the active material of the plates developed a thin, non conducting layer. Applying 17 volts in the normal direction simply reinforced the layer. Reversing the polarity very quickly broke down the layer. After that the battery was able accept charge. This seems like a worthwhile discovery.

On November 22, 2013 at 3:50am
Aakash Vikram Singh wrote:

this is a very great full site. thanks for sharing information.

On November 22, 2013 at 3:53am
Aakash Vikram Singh wrote:

Excellent and valuable information.

On December 14, 2013 at 2:01pm
Kevin Clifford wrote:

Coming to this forum rather late I wonder if this paper has been considered already, especially in light of John’s request for genuine scientific study?

Pulsed-current charging of lead/acid batteries - a possible means for overcoming premature capacity loss?
L.T. Lam *, H. Ozgun, O.V. Lim, J.A. Hamilton, L.H. Vu, D.G. Vella, D.A.J. Rand
Journal of Power Sources 53 (1995) 215-228

On December 14, 2013 at 3:30pm
Art Schultz wrote:

I read that paper and it leaves more questions than answers. My first thought is that pulsing desulfators don’t work that way at all. They do pulse at about the same rate, but with only miniscule amounts of current, and discharge current at that.

On December 14, 2013 at 4:54pm
shawn wrote:

All these discussions on pulse charging, pulse width and amplitude appear to indicate there is something to it but it is clear nobody really understands.  Quite similar to all the new battery chemistries and their unexplained results.  It will likely be a long tume before folks figure out what is going on and then turn that around into a product that optomizes the unlnown effect

On December 19, 2013 at 2:04am
Leon Bredenkamp wrote:

Interesting thread. Much enlightened but none the wiser. We use distilled water to top up our batteries and it was mentioned by a friend that what we buy as ‘distilled water is not distilled but reverse smosis treated water. If so is RO treated water good enought to use or will it destroy my batteries. Thanks

On December 19, 2013 at 4:19am
John Fetter wrote:

Leon - Once upon a time bottles that were sold with the label ‘distilled water’ actually did contain distilled water. Distilled water is very expensive and is overkill for use in batteries. Nowadays the bottles contain reverse osmosis water or deionized water, but the label has not been changed. Reverse osmosis and deionized water can be purer than distilled water. They are all safe for use in batteries.

On December 19, 2013 at 4:39am
Leon Bredenkamp wrote:

Thanks now I know. Regards

On December 20, 2013 at 3:27pm
Art Schultz wrote:

I’m not so sure I agree with the water recommendations. Even in remote Alaskan ports, water labeled something like “pure steam distilled” is available for a few dollars a gallon. It is hard for me to imagine that it would be less affordable elsewhere.

As for reverse osmosis water, maybe commercial reverse osmosis plants are better than onboard desalinators, but the specs I’ve seen on various units put the ion level close to standard tap water. Reverse osmosis isn’t perfect. It only brings water to an acceptable level for consumption. It could be perfectly fine for batteries (depending on initial source), but I would always be suspicious.

I have only seen de-ionized water in laboratories. A large lab building is often plumbed with a separate DI water line. I know the cost of lab grade DI water systems and I think of it as an extremely expensive form of water, but the whole point of using purified water in a battery is to eliminate unwanted ions, so DI water should be the ultimate.

On December 20, 2013 at 4:00pm
John Fetter wrote:

Art - A high percentage of industrial motive power batteries used by logistics operators in the USA receive plain tap water. I am talking about hundreds of thousands of batteries worth over $2500 each.
One must avoid certain impurities. Some impurities are harmless. The Europeans spend huge sums of money on highly purified water for industrial motive power. It is a matter of habit, more than a matter of science.
Batteries on standby duty must have very pure water. Most of the rest can do with water water having equivalent purity of high quality drinking water. Availability plays a huge part.
In theory, pure water is available. It practice it is often not.
I have seen batteries filled with pebbles in order to hold up the electrolyte level indicator. Someone did not want to drag a water container half a mile from source to battery. (In)convenience plays a large part, cost perhaps a minor part.
Power stations use extremely pure water. It is “polished” by deionization.

On December 24, 2013 at 12:49pm
Kevin Clifford wrote:

Here’s a paper that deserves consideration and published in the Journal of Power Sources (so should have been peer reviewed) and was presented at the 9th European Lead Battery Conference.

Novel technique to ensure battery reliability in 42-V PowerNets for new-generation automobiles (type into Google)

The company CSIRO Energy Technology has developed a pulse device for minimizing the development of lead sulfate layers on negative plates. CSIRO is hardly a cottage industry company.

On December 27, 2013 at 12:02am
John Fetter wrote:

Kevin - You have drawn attention to a document that describes a preventative, not a curative process. There is no confirmation of any batteries-in-distress rescue breakthrough. It is a document that explains something about battery pulsing with crystal clear clarity - needle-like high frequency pulses are useless. Profoundly disappointing news for the makers of pulse desulfators that treat batteries with narrow, high frequency pulses.
Energy Technology is a department of the Australian CSIRO. It is a reputable organization.
The batteries under investigation were being used to provide a large number of shallow discharge-charge cycles at high rate, in a partial-state-of-charge condition. The authors proposed a form of pulsing that superimposes a train of optimum duration, high voltage charging-current-producing pulses on the conventional charging current, to compensate for the undercharging that is being deliberately imposed on the batteries.
The authors explain that pulse frequency must be high enough to focus the effect of the pulses on surface sulfate, at the same time, individual pulses must be long enough in duration to overcome interconnection inductance and surface double-layer capacitance, in order to effectively charge the batteries.
The other paper, by Lam, Ozgun, Lim, Hamilton, Vu, Vella and Rand explains how pulse charging is able to overcome the open circuit barrier that seems to all too frequently to form between the positive plate grids and the positive active material of lead-calcium positive grid alloy batteries.
Perhaps the reason why, after so many years, no one has yet managed to provide a satisfactory explanation of how pulsing desulfates batteries is because, sadly, there is nothing to explain.

On January 3, 2014 at 6:53am
Garth Moore wrote:

Thank you for the very interesting read from top to bottom.

Just a little story to add from sunny South Africa…....many years ago we had a doggy-bone Ford Escort 1300, think it was a 1972 model. Anyway, it still came with a generator and the three relay control box. Point is, this car done short trips only and the original battery had given up the ghost. Not to be outdone, a (cheap) replacement was fitted and the generators voltage regulator relay adjusted to about 14,5 v…......that (cheap) battery lasted 7 years in that car!

On January 3, 2014 at 1:39pm
Chris C. wrote:

Indeed, great story. Keep the voltage up, keep the battery cool, top up with distilled water when it needs it and you should be OK. Short trips can kill batteries prematurely as the voltage never gets high enough.

It’s been -36C here lately and I recommend to all members of my family to keep their batteries topped up, it’s been so cold Ive seen a frozen battery for the first time in my life, the battery had sat two weeks in a car outside, unused, and the electronics had drained it enough that the electrolyte density had dropped to the point where it had turned into a slurry, and it took hours with the charger in boost mode (17V - if that happens make sure you disconnect the cables from the car, you don’t want to risk frying the electronics) to get enough amps through that it finally melted the electrolyte enough to let the charge go through.

Luckily as it’s been so cold the lead sulfates never had a chance to harden and I was able to revive the battery.

On January 3, 2014 at 4:04pm
John Fetter wrote:

Garth - You described a solution to what could arguably be described as the No 1 problem that has plagued motorists for 100 years - and one that the automobile, auto-electrics and battery manufacturers have gone to extraordinary lengths to ignore.
It is not difficult to equip alternator voltage regulators with adaptive voltage regulation. A chip that memorizes the way the car is used, counts the number of starts, duration of journeys, etc and adjusts the voltage impressed on the battery accordingly. Short trips - high voltage; long trips - low voltage, long periods of standing - boost voltage.

On January 4, 2014 at 3:07am
John Fetter wrote:

Bystander - Happy New Year.  Need to lighten up. Has the op shop in the big smoke left you stonkered?

On January 6, 2014 at 6:26am
Garth Moore wrote:

An extract from not one but two S.A. Battery manufacturers websites which say much the same thing about the new silver calcium batteries:
“The ideal charging voltage for a hybrid battery is 14.4V and for a calcium battery 14.8V. However, this does not mean that a calcium battery cannot be fitted in place of a hybrid battery. Tests have shown that the calcium battery will operate at a slightly lower state of charge in the car.”
Does anyone remember the “Torque Starter” battery of 30 years ago? Good battery, just it needed 14,6v to charge up and most alternators were running at 14v or less.

On January 6, 2014 at 6:44am
Garth Moore wrote:

To quote a comment from John Fetter on 21 April 2012: ” When the calcium type of battery is operated too long at low charge, an insulating oxide layer develops at the lead-calcium and lead-dioxide boundary.” Leading to an overworked half charged battery and early failure!

On January 6, 2014 at 7:28am
John Fetter wrote:

Garth - Those voltages correspond very roughly to the charging potential that would produce the same rate of gassing for the different grid alloys. They mean nothing in the context of battery life expectancy. Everyone has a story about this, that and the other battery. Given the optimum charging voltage, a hybrid will usually outlast everything else.

On January 6, 2014 at 5:17pm
John Fetter wrote:

Garth - PS   Silver-calcium batteries. I ran the numbers out of curiosity.
The cost of lead, per pound, is $0.98. The cost of silver, per pound, is $323.00. Silver-calcium batteries are sold at the same price as all other batteries. Therefore, how much silver might have been put into these batteries and would an economically justifiable amount have any real measurable positive technical effect?

On January 11, 2014 at 5:32am
Adrian wrote:

Has anyone ever tried an abrasive slurry and agitation by a mechanical shaking, ultrasonic or air bubbling to remove the sulfide deposits? silicon carbide or aluminum oxide?

On January 11, 2014 at 5:55am
John Fetter wrote:

Adrian - Everything under the sun has been done in the struggle to “desulfate” batteries, by many millions of enthusiasts, for over 100 years - except one very obvious thing.

On January 11, 2014 at 8:18am
John Davies wrote:

At the start of this section entitled—-SULPHATION AND HOW TO PREVENT IT——-it says, in the forth paragraph down, that during prolonged charge deprivation that a coating of lead sulphate forms on the NEGATIVE plates !!
Surely this should state BOTH plates as the chemical reaction needs BOTH plates to take place ???
The negative plate electrons chemically react in the positive plate and the lead ions left behind in the negative plate combine with the SO4 from the acid to form lead sulphate on the negative plate.
At the positive plate the lead electrons combine with the hydrogen ions to form water and the resulting lead oxide reacts with the SO4 to form lead sulphate and more water.

My argument is that both plates sulphate up and not just one as it says at the start of this section.

On January 11, 2014 at 8:23am
Chris C. wrote:

Adrian, great idea in principle but let’s not forget that battery plates are made of spongious materials with very high surface area and low mechanical resistance and any mechanical abrasion is bound to seriously damage them, as the sulphates get deeply enmeshed with them. You’d end up with plates with essentially no active material on them.

However, and I don’t know if this hasn’t been tried before, it would be interesting to know if this could work on stationary industrial cells with solid plates.

On January 11, 2014 at 8:41am
John Davies wrote:

If someone has gone to the great trouble of removing the plates from a battery to scrape them clean of suphate it would be much quicker to knock out the paste from the grids and simply replace it. Battery then 100% OK.

On January 11, 2014 at 8:57am
Chris C. wrote:

John, my point exactly. However if you read Adrian’s post, he mentions using an ultrasonic process which would arguably not use heavy mechanical abrasion. It would hover likely result in disintegration of the spongy material.  Food for thought…

On January 11, 2014 at 10:10am
John Fetter wrote:

John Davies - You’re right. Sulfation affects the positives AS WELL AS the negatives. However, the electrochemical conditions at the positives and at the negatives are very different when the battery is put on charge. The positives strongly favor lead sulfate to lead dioxide conversion, the negatives only very weakly favor lead sulfate to lead conversion. It is easy to reverse positive sulfation, difficult to reverse negative sulfation.
The belief that sulfate forms only on the surfaces of the plates is based on superficial observation. The bulk of it happens below the visible surface, deeper down in the plates. The surfaces look whitish, people believe they can see it, wash it out, scrape it off. The bulk of the sulfation is pitch black. Sulfate is not simply sulfate. Depends on the exact composition, hydration, crystal structures.

On January 12, 2014 at 4:35am
Adrian wrote:

Thanks Guys.  I might try it….. I am a machine builder not a electrical or chemistry guy.  I may build a rotator that gently rolls a battery around in a random pattern.  I know that the water jet cutting machines have made abrasives ( with tight size tolerance) suspended in water easy to get.  If the cells were partial filled, rolled around for while that might do show some results. 

Does the sponge material get fully occluded or just coated on the surface leaving passage ways?  To have any affect I would have to have flow.  Fully clogged would not work. 
Is there a test procedure that will help me test effectiveness of this process that will help to reduce the affect of draining and re placing the electrolyte?

On January 12, 2014 at 5:36am
Adrian wrote:

All- thanks for the efforts on this forum.  Its supper worth it.  Batteries and Motors, are the future. Not engines.    I’m interest in both solutions for the dead batteries all ready in existence perhaps future designs that make them better.. Dream big.

Sulfate ( of what ever type ) seems to be the boogie man.  I get that there is more to it just this.    But here are some questions?
Is it soluble in any known solution?  Soak the plates , rinse and refill is too easy.. right?
Is there a substance that sulfate has a higher affinity for that the plates?  sort of like the throw away zinc anode for ships .  Soak the whole thing in a tank and let the “goo” Migrate to the “goo magnet”.  Add current to ” Goo magnet” and all of the affected plates to move it along?  In future battery cells, a sacrificial / replaceable third pole that has current applied to it prior to changing..Replace and recycle it when it gets used up.
Sorry if these are questions that seem silly, but I am supper interested in this now.  Like a dog with a bone.

On January 12, 2014 at 6:46am
John Fetter wrote:

Adrian - There are ninety-nine other things you can do with batteries that have a better chance of giving you something worthwhile in return.

On January 16, 2014 at 8:08am
Jack Kline wrote:

Great posts people. Regarding these numerous desulfators out there, has anyone tried this German desulfator named AccuCare that supposedly contains microorganisms that basically eat sulfate off the plates? Here is the link to the Amazon page of the product and the home page of the company: http://www.amazon.com/Now-AccuCare-18ml-Revolutionary-Rejuvenator/dp/B00EMLUPBW/ref=sr_1_1?ie=UTF8&qid=1389884895&sr=8-1&keywords=Accucare and www.unifutura.com

On January 17, 2014 at 3:28am
John Fetter wrote:

Jack - The actual AccuCare website represents arrogant unauthorized use of proprietary trademarks and self-indulgent namedropping, merely to promote a product that is not German, likely to be no better than pasteurized bat droppings.

On January 22, 2014 at 8:55pm
Robert wrote:

The oil, battery and tires are some of parts of the car that the owner has to inspect and periodically replace. Pushing a battery life beyond 5 years is the same to try to revive a dead body. To understand the battery we need some know how in electro chemistry, physics chemistry and more. I absolutely agree to inspect the status of the battery every 2 to 3 weeks. Maintain properly the battery, keeping the voltage above 12.6 V, trickle charge if not in use, and put in desulfation mode (equalizing) 14.5V for 8 to 10 hours if needed. For me the most important thing is not to deal with a dead battery. Considering the cost about $100 to replace the battery ($20 per year) is not worth the time to try to bring back to life a dead body. With an engineering degree my batteries in all my family 4 cars last at least 5 years.

On February 4, 2014 at 3:02pm
Romina Arcamone Garcia wrote:

Trojan Battery Company launched on January 2014 a Smart Carbon technology for batteries in Partial State of Charge. This technology was the result of 5 years of R&D. It will allow to reduce sulfation increasing conductivity in the negative plate. Renewable Energy batteries that past 17 years life cycle under the IEC 94127 are being tested now to prove the benefits of the Smart Carbon technology.


On February 4, 2014 at 4:00pm
John Fetter wrote:

Romina - Solar power batteries are run in a partial state of charge almost continuously. Something nickel-iron was always able to do but not lead-acid. Hence your company’s Smart Carbon technology - designed to bring “power to homes that have never had access to electricity”. Can I ask how these new batteries would fare in situations where the batteries are left standing open circuit for extended periods, which would leave conventional lead-acid batteries badly sulfated?

On February 4, 2014 at 8:22pm
Jack wrote:

I have some other questions on the Trojan batteries:

- Can you compare and contrast to the carbon enhanced batteries targeted at automotice from the likes of companies like Exide and lead-carbon batteries like Axion?

- Lead carbon batteries tend to be quite expensive with 20-30% less volumetric capacity versus typical lead-acid batteries.

How many 50% charge cycles are possible?

I have been excited by this technology in the past, but the high cost coupled with reduced storage was a turn-off. Unfortunately they still suffer from high temperature oxidation like other lead-acid batteries.

And yes, how will they do under extended periods of partial state of charge. I don’t need indefinite, but if I can run a month at under 50% state of charge without long term damage, that would cover most if not all solar installations as I can force a full charge on a regular basis, just not that regular.

On February 7, 2014 at 4:33am
John Fetter wrote:

Romina - Carbon technology has been described by Boden, Calabek, Fernandez, Kozawa, Lam, Micka, Moseley, Pavlov, Sawai, Shiomi, Spence, Valenciano, Walmet, their numerous co-researchers, as well as other researchers. The researchers disagree about the underlying mechanism, disagree about the effectiveness of carbon and disagree about the optimum type of carbon. This would seem to be a controversial subject.  It would be appreciated if you would consider explaining the advantages of the Trojan system.

On February 12, 2014 at 8:39pm
Russ wrote:

I thought the following link did a good job explaining sulfation.


On February 13, 2014 at 6:33am
John Fetter wrote:

Russ - Sulfation in regular lead-acid batteries and sulfation in partial-state-of-charge lead-acid batteries arise in a different context, hence my question of Feb 4. A response is beginning to look increasingly unlikely.

On February 13, 2014 at 1:54pm
Misha wrote:

John Fetter, you are the smartest guy for lead acid batteries. Of course… I am just kidding.

On February 13, 2014 at 3:50pm
John Fetter wrote:

Ad hominem.

On February 14, 2014 at 1:12am
Misha wrote:

Ignorantia nocet.

On February 14, 2014 at 5:06am
Carl wrote:

This is only a test message.

On February 14, 2014 at 10:01am
Cadex Electronics Inc. wrote:

This is the BatteryU administrator smile

Be polite guys and keep the discussion fruitful smile

Brandon Crick | Marcom Manager
Cadex Electronics Inc.

On February 19, 2014 at 3:50am
ramkumar wrote:

in my company we are using toyota fork lift in that 1 batery cell get damage so we send the batery for service.  they made delay (because of pament) about 9 months
now we think to do service but they are telling to scrapped they are given the below reson

1. The battery has not been in use since about 9 Months where in which would have led to “Deterioration” & “Sulfation” of the other cells in the battery.
Hence it is not advised by us to JSAI to undergo this procedure.
This battery is not fit for use and need to be scrapped l

On February 19, 2014 at 7:02am
John Fetter wrote:

ramkumar - Check that the electrolyte levels are above the plates but NOT any higher. Add water where necessary. (The electrolyte expands when the battery is charged.) Simply put the battery on charge at a reduced rate, something like one twentieth of the ampere-hour rating and let it charge until it gets quite warm. This can take quite a few days. Then switch off and wait two-three days. Check the voltage of every cell. The low ones are probably duds.

On February 20, 2014 at 6:29am
Chris C. wrote:

John, I have a question:

What do you think of using an AC capacitor charger for a situation like this - by that, I mean a charger with constant current limited by the capacitor itself, but variable voltage which can go as high as needed to push said current over highly resistant sulfated plates? 

For those who are not familiar with the concept, it’s a charger designed with a motor run capacitor in series with a bridge rectifier and no transformer. As it can generate line voltages it is NOT a safe device to use and one must use an inline fuse for overcurrent protection (should the capacitor short itself).

On February 20, 2014 at 4:29pm
John Fetter wrote:

Chris - I would personally not hesitate to use a capacitor charger myself. I would definitely not recommend the idea to others precisely because it can be dangerous.
As an aside, I used a capacitor in series with the primary of a regular 12V charger to charge a single 2V cell. This worked perfectly. However, when I disconnected the cell with the charger still on, the transformer in the charger complained loudly as it went into saturation.
I prefer to use a more conventional charger that has a constant current facility. I have a thirty-year-old 50A thyristor controlled charger with infinitely variable voltage and infinitely variable current control. It uses series connected voltage and current control amplifiers. Two potentiometers. Preset the volts and amps. The charger pushes constant current into the battery up to the voltage setting. When the battery reaches this voltage the charger tapers the current and the battery settles down to constant volts.

On February 23, 2014 at 1:48pm
Chris C. wrote:

Thanks for your response… Your old charger sure looks sweet and exactly what I’d love to have! I just have a couple of run of the mill chargers now. Do you happen to have a schematic for that thyristor circuit? 

Long ago I made myself a very compact and powerful charger using a surplus industrial triac based controller on the primary, made the transformer hum like mad but worked great, even if I could only control the input… I had both an ammeter and a voltmeter so I could control its output that way, but you really had to check it constantly and I made the mistake of lending it to a buddy who used it for trying to start his car and burnt it out and I never got back to repairing it…

On February 23, 2014 at 4:30pm
John Fetter wrote:

Chris - It started life as an industrial dc motor speed controller. Unfortunately I lost the schematic. Motor controllers make first class battery chargers because of their control accuracy. Easy to program voltages and currents. The circuit is overkill because it is a four quadrant speed controller, meaning it can charge the battery from the ac supply, and then discharge it back into the ac supply. Useful when cycle testing motive power batteries. I only pay for the electricity wasted in circuit losses.

On February 27, 2014 at 10:31pm
Russ wrote:

This company claims to have a solution to solar storage at about the same price as lead acid.


On February 28, 2014 at 2:30am
John Fetter wrote:

Russ - I had a good look at that website. I heard a loud suction sound that seemed to be aimed at investors. I read all their patents. There does not appear to be a single decipherable explanation on how their battery works.
I did not find any information on prices.

On February 28, 2014 at 8:55am
Russ wrote:

This is the article that brought me to their website. It claims that they are shipping to customers for evaluation. The battery tech and pricing claims are in a few paragraphs at the end.


On February 28, 2014 at 1:06pm
Chris C. wrote:

” I heard a loud suction sound that seemed to be aimed at investors” that made my day, hadn’t had such a good laugh in quite a while… :-D

On February 28, 2014 at 5:34pm
John Fetter wrote:

New technologies, new companies. This company is running a very elaborate, highly polished publicity campaign and is saying next to nothing about the actual workings of the battery. I find the descriptions that are given focus on soothing features that seem to have been cherry picked from a list of the perfect battery features. I like to see plenty of engineers/ technicians, not a boardroom brimming with executives.
When Edison began selling light bulbs, he began by selling them below cost. The product proved itself. Sales went through the roof. Edison made money.
This could be done to promote sales of batteries, provided the investors have very deep pockets. The battery would have to be PERFECT, not merely very good, because, unlike Edison’s light bulb, there are plenty of other types of batteries already out there.

On March 1, 2014 at 12:23am
Russ wrote:

Well i am just a seeker of knowledge and i have learned a lot from you John through your posts, I had never even thought about the incompatibility of lead acid batteries and solar power before this discourse. So what do you think is the best battery configuration for operating in a constant state of partial discharge?

On March 1, 2014 at 12:38am
Art Schultz wrote:

This “constant state of partial discharge” is also the case for thousands of small boats, some times using wind or solar panels, but more often using the engine for short charging periods. That is my situation. As far as I have been able to determine, the best battery would be a lithium pack. I have lead acids and it seems that I would ultimately save quite a bit of money at my next change by going for the longer life of a lithium bank.

Somebody, anybody feel free to talk me out of this before I make a terrible mistake, but at the moment a big Chinese made lithium bank is looking better and better.

On March 1, 2014 at 12:59am
John Fetter wrote:

Russ - It is an interesting subject. Look at Feb 4, above. This is a discussion page, so I asked the obvious question. The fact that there has been no response speaks volumes about the technology. It has become quite common for companies to make these kinds of announcements. I believe nickel-iron works well in a constant state of partial discharge.
I can see a huge opportunity for lead-acid in a series hybrid automobile. Engine, generator, battery, speed controller, electric motor. Electric transmission with energy memory. Very difficult to design a battery for this kind of application. Not impossible. It is a mindset thing.

On March 1, 2014 at 3:00am
John Fetter wrote:

Art - Lithium is a complex, controversial, expensive technology. Lead-acid is a complex, controversial technology.
It is possible to make lead-acid work in constant partial state of discharge using a simple precaution. Bring the batteries to full gassing charge no less frequently than once a month.

On March 5, 2014 at 7:26am
mark diodash wrote:

funny used to get 3 yrs out of my motorcycle battery, driving mostly local cars the same.

Now i drive all highway and get 6 or 7 yrs out of a battery. My tennis ball machine ,I get 6 yrs out of the battery. I charge this every time i use it.

On March 7, 2014 at 3:43pm
Darell Engelhaupt wrote:

John, you mentioned Edison NiFe batteries for stationary use. My grandfather had a 1913 Detroit Electric which ran on the same Edison NiFe alkaline batteries for more than forty years. Jay Leno has a similar Baker Electric today and has but one original battery about 100 years old and still holds a charge. More could be done with this type battery using higher specific area electrodes and modern plastics to build a lighter version.

On March 7, 2014 at 4:17pm
John Fetter wrote:

Darell - Yes. I agree.
However, people are not interested in buying good batteries but in buying the least expensive batteries. There is no technology barrier but a commercial barrier.
As an aside, people use expensive lithium only because it reduces the size and weight of the equipment powered by batteries to a sufficient extent to overcome objections to price.

On March 30, 2014 at 6:20am
Adam R wrote:

Couldnt sleep last night so read entire forum, thanks for fascinating and entertaining exchanges. I live on a boat and help design and build electric cargo trikes in Bath UK - Cycles Maximus. I use Enersys AGM in both bike and boat, CTEK charger on bike alternator and modified Adverc on boat.  Bike battery now on 500 cycles and going strong with 12.85 v after charge.  Boat battery on 150 cycles and Sulfated although MPPT solar charger and 300A alternator with temp comp controller running 14.6v boost at 25 deg.c. Have nust purchased square wave pulse desulfator with high current capability. After reading forum not sure this will work but will let you know soon. What do you suggest for boat charge as max charge time allowed on inland waterways is 12 hours in one day? Understand that I may not be getting 110% back in which can cause sulfation. However CTEK on bike giving top performance due to plugged in at work when not used so constantly getting full recharge.  However prior to CTEK I used Mobitronic with identical charge algorithm but NO initial desulfation phase. In this configuration AGM battery only lasted 250 cycles with slow deterioration of capacity. So what is going on if desulfation pulse charge is a red herring? CTEK absolutely works here. Enersys Newport have AGM up to 1200 cycles with high current charge in lab using similar charger.  Look forward to reply.  Would love to fit NiFE but wide v range would mess up installed electronis and cost very high.

On March 31, 2014 at 3:35am
John Fetter wrote:

Adam - When one looks for problems where none exist there is a real risk of finding a problem that cannot be fixed.

On March 31, 2014 at 4:31am
John wrote:

John Fetter,

After reading Adam R.‘s valid application post, I fully expected an asinine response from you that would be dripping in sarcasm and would provide absolutely no value to the community or the poster.

You did not disappoint.

On March 31, 2014 at 5:05am
John Fetter wrote:

John - You missed an ideal opportunity to share your knowledge on this subject.

On April 7, 2014 at 10:33am
engr murad wrote:

                      i have got 150 batteries of 12 v 65 ah sealed lead acid they were dumped in store from last four years they are new and not used . now they are not charging and voltage not rise from 9 volts please any body help me what should i do with them to use them need ur comments please…..

On April 21, 2014 at 4:50am
brian wrote:

Adam R: in Bath,  how are you getting on with your desulfator

On May 10, 2014 at 6:02am
Neil wrote:

Hi, I use desulphator pulse ccts. They work. I worked at uni in physics. I researched the hard sulphate crystal build up on plates. I found research expt hi res photos of before and after (on net) showing how much had been removed - lots. It grows like a fungus and robs active material and plate area and increases resistance.
Imagine the copper sulphate crystal growing expt you did in chemistry. Take water, add crystals, heat up and stir. All dissolves. let cool and wait. Crystal grows from seed.
The pulsator effectively ‘stirs’ the solution, it shocks/vibrates the crystal molecules back into solution. No mystery or magic. Heating battery or keeping it warm somehow helps too. Pulses probably work best in conjunction with battery being charged, topped up, warmed. Without pulses batteries could not be improved. small charge/discharge cycling helps, probably by redistributing lead sulphate layer more evenly, warming, keeping lead sulphate out of solutionHi, I use desulphator pulse ccts. They work. I worked at uni in physics. I researched the hard sulphate crystal build up on plates. I found hi res photos of before and after

On May 10, 2014 at 6:29am
Nei wrote:

Oops cut and paste without last check!
I’ve heard many arguments against pulse desulphation, butmy own results proved it. I was a skeptic at first. There is so much disinformation, politics/agenda, faulty logicians exercise, etc.
my advice is to buy a cct and try it for yourself, only €20 odd. I have six, hoping to assemble and pass some on to friends.

On May 10, 2014 at 9:11am
John wrote:


You’re wasting your time.

On May 10, 2014 at 9:50am
Chris C. wrote:

I would have to agree with John, in my experience it makes no measurable difference, however regular, properly conducted equalize charging standard flooded batteries does.

On May 10, 2014 at 11:45am
Neil wrote:

@john fetter
I do not think that self discharge causes batteries to sulphate. The sulphate is in solution, quite concentrated, and given time, low temps, etc, hard, well structured crystals have the chance to form. It is a fundamental process in nature. (e.g. copper sulphate crystal growing expt.. Lots of dissolved rock material and stuff, form crystals in nature, that list is a long one)
Any form of increased shock/vibration/resonance that can energise the surface molecules of the hard crystals back into solution, even as simple stirring does for the hard sugar/copper sulphate granules, will reduce such build up of hard sulphate crystals on the plates. Heat helps dissolve stuff too. Note the use of ultrasonic cleaning baths, using sound waves to dislodge dirt and shite.
A short pulse of high energy, say 30V will cause ions in the electrolyte to move, literally, physically. Some of these are bound to bounce of and have the mechanical energy to dislodge the weakly organised molecules of the crystal structure, probably starting at the edge of the mould-like patch of sulphate.
Molecules have mass and will respond to certain frequencies of vibration, i.e. start to vibrate themselves and detach from their cosy crystal lockin (which isn’t that strong - only appears so because there are so many holding themselves in a regular structure - how do you think diamond cutters work, they cleave along weak ‘fault type lines’. Also, the weakness is evident from the fact that it takes time and proximity for the molecules to line themselves up and fall into place - it is nothing like a chemical reaction as such, it is more a preferential interlock of mild electrostatic potentials, not electrochemical bonding proper, although I think I read somewhere that some do progress to full chemical bonds. Ordinary temperatures can prevent crystalization, cool stuff down, reduced vibration, and the subtle potentials can do their stuff, organise and lockin.

The molecule/crystal is not then ‘shed’ and lost - but made free and dissolved back into solution.

Voltage is the same as e.m.f. - electromotive force, force, real physical force on electron/ion ‘structures’/particles and thus pulses of voltage impart mechanical vibration/motion of same. That’s hwo a light bulb works, why stuff gets hot, etc.

There is nothing magic or mystical - other than the wonder of nature herself, here. It works - logically, reasonably, and in practice.

As to lead acid battery chemisty, if you look at it simply it is simple enough. If you care to look deeper, I believe it is not so well understood, indeed there are some things taken for granted, e.g. why the electron does not collapse into the nucleous of an atom. No one can tell you why - check it out for yourselves, there’s a lot of ‘explanation’ that does not actually give you a real why.

The planet hasn’t warmed for over 17 yrs and yet even top scientist are promoting it and trying to earn money from it.

On May 10, 2014 at 12:09pm
shawn wrote:

Neil, excellent response….the electrical pulse desulfation is effecting the lead sultate crystals mechanically. From your thought,  “A short pulse of high energy, say 30V will cause ions in the electrolyte to move, literally, physically”, I agree with this but I also recognize this is a high ineffcient electrical to mechanical conversion process.  What concerns me about the high voltage spikes is the side effects of such simulation, i.e. electrolysis of the remaining H2O molecules, especially in heavily discharged battery.  I have been testing the high frequency mechanical effect for 11+ years and I am seeing significant benefits in this approach.  Your discussion was refreshing.

On May 10, 2014 at 5:12pm
Neil wrote:

lets think about this - its late and I need go bed. But just to say, I don’t think that electrolysis is a concern here. Brief reasoning… normal gassing is minimal until the battery is near full charge and lead sulphate in soln used up, so I’m guessing that there will be a preferential ‘focus’ on the sulphate/lead oxide interface, especially near the edge of the hard sulphate ‘mould’ deposit and especially as that sulphate is returned to solution at that point. This may be the reason for good results found and that we see improvement so quickly - it actually starts at the thinnest point of the ‘mould’ at the edge and quickly reveals more plate surface area. If it tackled the main mass of the hard crystals from the off, it would take longer to see appreciable results (having to dislodge a thick layer of hard crystals back to plate lead oxide before .improvement due to extra surface area of active plate.
If I were in a position to experiment further (will be a while) I would focus on the best resonant frequency pulse as some have done or guessed at in the past - wondering where that 3.2MHz pulse freq came from originally - I think it was a paper by some very reputable/respectable forces or research group in usa. Next I would increase the number of those pulses per second to find optimum. Another thing I would do is warm the battery up to 40 or even try 50 deg Celcius along with continuous shallow charge/discharge cycling.
shawn, I haven’t read all the posts here, few if any of yours, but will get right to it (tomorrow if I can). Am interested in sharing research/findings/results/experience/reasoning, etc with you and likeminded, thanks for your own response. I was into this a few years back and have just got camper van and am hoping to be off grid with new place when contracts exchange. I have just bought two 3000F Maxwell Boostcap six packs off ebay. Been playing wih those today. Cool stuff.
Kind regards
will be back soon

On May 10, 2014 at 5:21pm
neil wrote:

@shawn just to say I am guessing that the process is a mix of electromechanical/‘ionical’ and mechanical - which could be another insight for experimentation to find perhaps pulse height to pulse width optimum ratio with temperature combination/variation too.

On May 10, 2014 at 5:55pm
shawn wrote:

Neil, the right mechanical excitation is not ‘breaking’ anything, it is preventing in the first place.  We do not let the crystals nestle and form, we are a preventative technology and we employ mechanical methods…thus, we do need to use the terminals.  a lot of thought and science behind this and we would love to discuss.  Electrical stimulus in our frequency and amplitude range is in fact damaging to the batteries life!

On May 11, 2014 at 12:27am
John Fetter wrote:

Neil - When you say that self-discharge does not cause sulfation, you are asserting that for the last 130 years, every battery manufacturer has managed to get this thing wrong. It puts a damper on your credibility. Your explanations make interesting reading. Your assertion that the planet hasn’t warmed for over 17 years is extraneous to the issue under discussion, although it does confirm that you believe in alternative science.
You are at the bottom of a very long learning curve.
If you want to be taken seriously, you need to provide details of measurements. Before treatment ampere-hours, after treatment ampere-hours.

On May 11, 2014 at 5:58am
Neil wrote:

@john fetter.
In line with my earlier comment about lead acid batteries - if you look at them simply they appear simple, but if you look much deeper, there are things going on that are subtle and, even today, not understood. To be accurate, I wrote that ‘I do not think self discharge is the cause of sulphation’. I then quite clearly, I thought, described that there is a natural mechanism for crystal formatiom. This is evident all over the world in geology, with some amazing crystals, etc, etc. I mentioned the copper sulphate crystal growing expt in chemistry that most do when they are 12. These are evidence of a real and solid natural process of crystal formation. You do not seem to acknowledge these or their relevance for crystal build up in lead acid batteries. To be more specific in what I think, just to be clear for you, I attribute much of a natural process to the formation of crystal in batteries. In as much as the self discharge will put pbso4 into solution that can then be involved in making crystals, I can accept that self discharge could be said to lead to crystal formation but not, I think, actually cause it - beacause the cause is a natural phenomena. And reasoning further, it seems quite logical to expect that any mechanism that promotes the dissolving of crystals, i.e. heat, stirring, vibration, will have some beneficial effect on crystals in a l/a battery. Add to this the fact that many have tried it and found said benefit, it seems to me there is something that does actually work, in practice. Now I know that many or most that have tried it have not done so under strict lab/science/experimental conditions, and that other effects would undoubtably be involved - but that does not prove said benefit does not exist.
You refer to my credibility - please shoot me down more specifically and accurately and I will gladly respond/explain my position, clarify and where wrong, I will acknowledge same and hopefully learn something in the process. You undoubtably have some interesting points yourself but seem to pick on semantics or others economical use of words, or even misquote/avoid detail in what has been said to make your own point or have an intellectual pop at someone else. I will not play this juvenile game. In reading your early comments, at the beginning, you seem to dismiss totally the possibility of pulses being able to reverse sulphation of l/a batteries, even referencing 70 or so patents that you claim have no merit what so ever. Really? ... really? You then slightly later, say that pulsing batteries can work! I am confused. You have spent a lot of time on this thread and, I feel have something worthwhile to add, but seem at times absolutely against the idea of beneficial pulssing effects.

You write to me…“You are at the bottom of a very long learning curve.
If you want to be taken seriously, you need to provide details of measurements. Before treatment ampere-hours, after treatment ampere-hours.”
I respond…Before treatment ampere-hours - NONE, After treatment ampere hours - lots and lots. !
Is that good enough? Of course it shouldn’t be.
As mentioned above, experiments have to be carefully devised, etc, etc, to technically rule out other effects and home in on one particular mechanism/phenomena. None on this forum, I suspect, have the technical equipment, and all other wherewithall to satisfy someone who is determined to deny something that others have found merit with. If you spent half the time buying a good unit and trying it for yourself, satisfying your own critical (in a good way) analysis, as you have writing comments here, I’m sure you would be applauded/appreciated and probably learn somthing real in the process that is valid to share here.
So what did I do to arrive at my conclusions? I started skeptical. The most obvious thing to do was look for other studies/experiments that prove the technilogy. I found thru google, a few website pages showing scanning electron photos of sulphated plates before and after pulsation, with the details of the trial/experiment clearly set out. That, and other reasons (one of which is the shear number of people doing it (not scientific based reason, I admit), another reason was a study done by a highly prestigious forces or research co in america, and others, these can be found on th web) made me want to give it a go. I did my searching a good few years ago and satisfied myself beyond doubt that there was soemthing here that worked. So I spent my €18, assembled a cct and gave it a go. And it worked.

OT global warming issue - don’t take my word for it - look at WUWT website - now that gives us the real science, not the AGW crap - and that conclusion, no warming for 17 yrs is held by many many top notch scientist not involved in politics, and some that are.

On May 11, 2014 at 6:51am
Neil wrote:

I know nothing of your technology/system - can you point me in the right direction to read up/ find out?

On May 11, 2014 at 6:56am
John Fetter wrote:

Neil - I have been spending several tens of thousands of dollars per year on battery R&D out of my own pocket since 1999. I have run many thousands of battery tests. I always run comparative tests. The solubility of lead-sulfate in battery acid is in the region of 4 parts per million.
My tests have revealed that if a battery has been left discharged for a shortish period, pulsing will help. Pulsing can charge a battery. Pulsing cannot do anything for fully sulfated battery. Sulfation is caused by neglect. It is not a symptom of aging. The only way desulfation merchants can hope to sell their products is to insist that sulfation is age related. I traced the 3.2 MHz resonance information back to its source. It is marketing sizzle.
You got to read the patents to see what successive inventors have to say about the previous inventions. People are permitted by law to patent ideas they do not understand. That is why there are so many desulfation patents. The large number of patents tell a story. They are not getting it right.
There are between 500 and 800 cars per person in the developed world. Nearly one lead-acid battery per person. One should be able to find a desulfation center in almost every major shopping mall. Where are they?
You need to use a balanced approach, part hands-on, part engineering, part scientific, part business, part entrepreneurial, part statistical.
As for global warming - here is a thought experiment. Fill a bathtub with water. Put in a big bag of ice cubes. Stir thoroughly. What will be the temperature of the water? Move half the cubes to one side, the other half to the other side and keep them there. If the room is hot, the temperature of water in the middle will rise slightly. It will not continue rising because the ice keeps it down. The warmer the room, the faster the ice will melt. The temperature of the water will rise only very slightly.
Everyday ambient temperatures aren’t rising very much because the northern and southern ice packs and glaciers are stabilizing the temperatures. The ice is melting, hence there is global warming.

On May 11, 2014 at 6:59am
Shawn wrote:

Neil, send me note at shawn@activegridtech.com

On May 11, 2014 at 8:07am
Neil wrote:

@john fetter.
With respect, it is well established that the majority of batteries (in cars) are rarely kept at optimum charge (esp winter short trips) - few if any are permanently on charge, all the time, so in as much as the average battery user does not keep optimum charge in their battery - evidenced by industry statistics that 80% of battery failures are due to sulphation, it follows that batttery sulphation appears related and correlates with aging. You dismiss a lot of people with that one technical/split hair. It is a correlation for sure but the fact of neglect from the start is a given and thus as time goes on the damage increases, obviously for 80%. That is the before. How can that invalidate the claim to a fix after? Thus I find your statement “The only way desulfation merchants can hope to sell their products is to insist that sulfation is age related” to be disingenuous and frankly wrong.
The 3.2MHz is not bogus _ found a source for it out of the usa - You’ll have to google it and find it yourself - i did that a good few years ago, maybe its been removed. since.
It is not difficult to experiment with that function of the pulse. You say a range of pulses works.
Why does the ‘large number of patents tell a story. They are not getting it right’. seem valid to you? If anything makes sense to me it is that tens of people have found something and tried variations that seem to work. That they can’t explain it to your satisfaction, or very well at all, does not invalidate their belief/experience/results. If you had said there’e only 3 patents and “they don’t hold water” then…
I’m sorry but I am confused by your varying comments - some seem to support pulsing, if only for sulphation that is not too bad, and others seem to claim it is all hokus pokus. Bewildering.
You’ve done some impressive investment in testing/research - surely you got something to report? All your claims are based on no proof of it. It must be falsifiable, possible to disprove, where is any of this data - why did you not figure something out of that in your investment - surely a first step? Able to say ‘It does not work because ...x….y and z QED’. YYou claim noone has proved it does work, you deny the heat/vibration/resonance/stirring to dissolve a crystal? For someone with such resources - lab and money - I’m suprised you did not find something. My lab was my google searching and that others had done some pretty smart research/chemistry/experimenting/reporting and put it on the web. Not so much of that happens these days because people want to charge for info/make money - nature of the rat race - notwithstanding the public money essentially paying for it or most of it.

I won’t argue global warming with you - you’ve got months of reading of WUWT threads or even jsut catch up with a few of the latest - will blow your mind - if it is open.

On May 11, 2014 at 2:15pm
John Fetter wrote:

Neil- Thank you for your insights. The automobile battery, as we know it today, was invented by a number of workers including Theodore A Willard of Cleveland, Ohio, USA in the early 1900s. Sulfation has been an issue ever since then. Millions of people have tried to do something about it since these early years. Their success or rather lack of success is there for all to see. There are relatively very few desulfation specialist business out there. These people work very hard, make enough to live on, that’s it. There are a billion automobile batteries in use worldwide. The opportunities are for the taking. The technology simply isn’t up to the task. Alternatively, there simply aren’t that many batteries getting sulfated.
Businesses that make a living out of selling desulfation products will make claims and back them up with information that is carefully selected. This is a perfectly normal marketing ploy. The most important thing I have learned about mining for information on the internet is to treat this info, in particular, as unreliable.
The overwhelming majority of car batteries eventually wear out. There is a minority that becomes sulfated. If that was not so, there would be many successful desulfation centers out there. It is a simple logical process to work this out.
If you are sure about your crystal theory, you need to run unambiguous tests to satisfy yourself it works. Then file for a US provisional patent. After that you can tell people about it. If they believe you are right, you will make a fairly large amount of money. You will be able to protect your patent by sharing it with a contingency lawyer. 

On May 11, 2014 at 4:00pm
Neil wrote:

@john fetter
thank you for your view. It was stated, a few years ago, by the industry, that around 80% of battery failures are due to sulphation. I believe this is accurate and established and true. Do you have reason to doubt this?
The way I see the car battery market is that it is just convenient to replace a battery that’s playing up with a new one for a hundred bucks. Problem solved, no messin. dIt will, they do, last a couple of years min, whaatever way they get treated, as far as being in a car under the hood.
People, majority, don’t want to know what is under the hood or how it works or bother keeping a battery topped up with charge - hell no, all that thinking, and testing and then plugging something in and connecting red to red and black to black, checking water even. So even if a magic pill came out that you put one of in each cell, overnight fix, people (majority) would still not bother. Perhaps a few thousand or tens of thousand of diy car types would love it for sure, but that is not big business at all, just a small minority. Halfords are selling a 115AHr leisure battery for €99 with two yr guarantee. with a free sleeping bag if you spend over €100. People like buying new stuff.
I’m not sure any technology fix can break the current cycle (double double joke there)
I’m careful about the info I get off teh internet, have good logic/intuition/reasoning skills - I do fine.
I don’t agree with you about desulphation centres - just doesn’t seem to me that it would work that way - far from a logical process in my opinion.
The crystal phenomena is not a theory, it is phenomena of nature. It is natural therefor to reason that this phenomena seen in a battery, i.e. crystals growing on a plate, has the same underlying causes and effect, same result - if it didn’t we wouldn’t call them crystals - so all known reasoning around that phenomena must be applicable, to a greater or lesser extent, to lead acid battery. Temp, concetration, vibration, friction, atomic structure, crystal lattice, etc. Play with all of these to see waht can be done. And that is what people have done. And got result. An example of knowledge and application of one principle - as far as I’m aware there is a common practice to keep l/a batteries off a concrete floor - garages know this, they might not know why they deteriorate so fast if you leave them on a cold garage floor, but it doesn’t take much to figure it out. They got there from experience tho’.
I have no interest in patent and making money from this - as far as I’m concerned someone, perhaps many got there ages ago, well before I did. I’m happy to buy my components from them make up a cct and bring a battery back to life. Fun, playtime, hobby. I like to think about these things and why this or that, or how this or that works.
I feel you are too narrow in your view of what can work and how it can work. No harm or badness in that, just your particular nature, but there’s an incredible world out there and it obeys laws and human beings can and do reason well and find things out - I feel you limit yourself. Perhaps you might open up a bit, take a risk in thinking something must logically work a certain way. You never know what you might discover.
Whilst I agree that to counsel newbies to be careful, not to believe everything they read, and watch out for scams, being scammed, and perhaps a few ‘if that was so ... then this would follow, scenarios, but I get the feeling you want more influence, and that it is perhaps too negative for the healthy spirit of searching, discovery and experimentation that visits this thread. I hope you don’t mind me saying. With all due respect.

On May 11, 2014 at 5:11pm
John Fetter wrote:

Neil - I make a very good living out of new technologies. I go about it in a business like way. I love new ideas. I refuse to go anywhere near moonbeams. If I understand you correctly, you are under the impression that leaving a battery on a concrete floor is a bad thing. This is one of those weird beliefs that is 100% bogus. You appear to have a very long way to go.

On May 11, 2014 at 5:55pm
neil wrote:

Appearances can be deceptive, especially to someone like you it seems.
It also seems common sense, logic and reason are lost on you john fetter as you generalize, dismiss and know so much 100%. No room for real progress by yourself, so I will desist.

On May 11, 2014 at 11:32pm
John Fetter wrote:

neil - The use of the lower case n indicates you’re angry. You’ve read widely on the internet and based on what you read formed an opinion.
That information contains very few hard facts. Most of the information is either incorrect, blatant lies or garbage. You give the impression that you have not had much technical and engineering involvement with batteries, other than tinkering.
You have an idea you want to discuss. Nothing wrong with that. Then, when someone makes a comment that is not to your liking, you quickly turn on the person, make derogatory inferences, rather than discussing the matter.
I used a standard debating technique. Someone stands up, makes a point. The next person disagrees. The first one explains, the second one interrogates. The argument goes to and fro. If the person who made the point actually has a valid point, the second concedes.
You have a very long way to go.

On May 12, 2014 at 2:41am
Neil wrote:

Very, very interesting, exciting even! Have more to read yet, but I have the basic concept.and see (some of) the incredible possibilities ahead.

On May 12, 2014 at 2:49pm
John Fetter wrote:

Neil & Shawn - I am pleased to see you both seem happy to explore your ideas together.

On May 14, 2014 at 4:46am
Garth Moore wrote:

An extract from ” C.F. “Oberon” Class Submarines Training Notebook for Electricians”;

The battery agitation system is one of low pressure air (1 1/2 p.s.i.) which is fed to each cell in the submariners main batteries. This air goes to the bottom of each cell through a tube fitted inside each cell and comes out in the form of small bubbles. These bubbles rise and tend to get the electrolyte within the cell moving. This rising motion of the electrolyte keeps it all mixed within the cell.

The system is used to prevent stratification (prevent different density layers forming inside cell).

It also prevents high temperatures in local spots within cells and reduces all charging times by one hour.”

As stated earlier, the movement of the acid within the cell is important - the whole handbook is on the internet and makes interesting reading. Regards from sunny S.A.

On May 14, 2014 at 5:21am
neil wrote:

@ garth
Interesting, thanks for link will look that up

On May 14, 2014 at 5:41am
neil wrote:

I have 13 glass jar batteries. they were emptied of acid and stored for years at university. I would like to revive them and was thinking of extracting paste from the good cells of defunkt car batteries and pressing in to the grid structure of these bats, they dont seem to have much as they stand. I’m guessing they will take about 5 litres of acid to fill. They are about 30cm tall, 20cm wide and 15cm front2back. anyone have any experience with these, or any info of what way to restore them? I can’t find any useful info on the internet.

On May 14, 2014 at 6:47am
John Fetter wrote:

neil - I can confirm that your idea to repaste the glass jar batteries can be made to work. I have done this kind of thing myself. I used a spinning blade coffee grinder to repulverize the active material. Simply mix with dilute acid to form a cement-like paste. This mixture will get hot. You will need to hold each assembly together with suitable thick sheets or planks and clamp VERY tightly while the acid and the paste react and harden. After that you need to form the plates by charging for an extended period.

On May 15, 2014 at 4:08am
Oscar Ormond wrote:

Neil insists that 80% of batteries fail due to sulphation and describes motorists as people who don’t want to think. (May 11, 4.00pm.) He claims that people do not care about what goes on under the hood and find it convenient to pay for replacement batteries. He insists that people like buying new stuff and that DIY is not big business. He claims that if a magic pill came out that could provide an overnight fix, people would not bother.

It seems that Neil is too preoccupied to realize the meaning of his own words. No one cares. You said so yourself. Why are you messing around in crystal fairyland? The way I see it, your internal red and black connections are reversed.

On May 21, 2014 at 10:41am
Robin wrote:

John Fetter, may I ask, something puzzling me. Pb and PBO have an electro chemical pd of 2.1v - I think, so why does this voltage increase when equalising charge is applied to say 2.5/2.6v - with the charger disconnected for measurement of course.  Yes it settled down again to ca 2.1

Similary why does the no load volts of a discharged battery dip below 1.9

We are not dealing with any internal ESR loses as no significant current is drawn

Pls advise

On May 21, 2014 at 1:48pm
John Fetter wrote:

Robin - You know that the positive plate contains lead dioxide and the negative plate contains lead on full charge, and that both contain lead sulfate on full discharge. The open circuit potential of a fully charged battery is, as you correctly stated, 2.1 volts. The theoretical open circuit potential with lead sulfate in both plates is zero. The cell is never really fully discharged. That is why you measure intermediate voltages.
Most of the extra voltage you measure on equalizing charge is developed at the surfaces of the plates by gas barriers. The negatives develop by far the most extra negative potential through their surface gas barriers. There are other interpretations. I have measured these gas barriers, experimented with them, increased and decreased them at will.

On May 28, 2014 at 2:19am
Ray Wu wrote:

desulfater pulse frequency is in range 3.5 MHz if I recall.  Google or wiki to get details.  (reply to john in early comments). this pulse frequency excites or exercises electrolyte causing soft sulfer formed on conducting plates loose which frees clogged conductive plates to freely react with electrolyte.  my friend had two of these chargers although his looks out dated but it revived two dead batteries over night..even use it to maintain to recharge batteries.

On May 28, 2014 at 2:20am
Ray Wu wrote:

edit reply to John Fetter’s comment.

On May 28, 2014 at 5:58am
John Fetter wrote:

Ray Wu - The 3.5MHz, the sulfur and the two revived batteries represent expressions of faith. It is not science. It can become real science if you can repeat a positive outcome with 100 batteries in succession, (although some would say a thousand times with no more than one failure).

On May 28, 2014 at 3:47pm
John Fetter wrote:

neil - It seems that there is consensus among battery desulfation enthusiasts that lead sulfate crystals keep growing larger, causing a form of sulfation that is irreversible under normal conditions. They claim this condition necessitates the use of their proprietary remedies to resolve.
It is often suggested that this growth is governed by ostwald ripening - a thermodynamically driven process that favors formation of larger crystals over smaller crystals.
My question is simply this. What is the difference between a small crystal and a large crystal in terms of this effect? Their relative energies.
If there is sufficient energy available to convert small lead sulfate crystals into lead metal crystals and sulfuric acid in a normal charging process, surely there will be sufficient energy available to convert large lead sulfate crystals as well? The only difference between the two would be the time taken to complete the process. If larger crystals require more energy, then increasing the charging voltage moderately will address the problem.
It is often suggested that the poor conductivity of lead sulfate crystals prevents larger crystals from being absorbed. However, the electrochemical activity is confined to the actual surfaces of the crystals. Ions are are half in and half out of solution on the surfaces and are highly mobile. The charging voltage will drive the reactions to favor conversion of lead sulfate plus water into lead metal and sulfuric acid. It takes longer to convert larger crystals.
If the desulfation enthusiast crystal theory is correct, the solution would be to simply put a sulfated battery on charge and wait.
I suggest this is as good a start as any to a logical discussion.


On May 28, 2014 at 4:00pm
Shawn wrote:

john, I think the answer to your question is that the ‘surface area’ of a bunch of small crystals compared to fewer larger crystals is greater and therefore more area in contact with electrolyte and therefore better and more efficient recharge.

On May 28, 2014 at 4:38pm
neil wrote:

Hi Shawn, this is my understanding…
If you look at the more complex stuff going on you find different stages and processes of crystal formation. The chemical reaction formations are bonded chemicals that form the small crystal like structures with lots of surface area. Because they are chemical or electrochemical in nature they are the ones that charge/discharge, giving up bond energy voltages when discharging and being formed from appropriate voltage levels that charge. The hard crystal formation does not involve same chemical/electrochemical bonds or structures. They are hard and unconductive/nonconducting and rob electrolyte active chemicals. They form from a different process and form bigger crystals, low surface area, nonconducting faces. The higher pulse voltages, at a resonant frequency, will smack all conducting surface ions/crystals/fluid. It would be interesting to find out, and you might know this Shawn, the mobility of ions as the electrons leave electrodes and enter solution. I think this is the vibration/stirring/friction sandpaper that rubs the hard crystals - as well as the effects you told me about - increasing reaction times, reducing reaction ‘resistance’ and keeping the barrier potentials down. It is a few years since I was really into this stuff so forgive if seems bad explanation, but I know what I mean! When will you have something to try out for the likes of joe bloggs me?

On May 28, 2014 at 5:32pm
John Fetter wrote:

Shawn - If surface area plays a part and it is simply a matter of efficiency, then sulfation will always be reversible. We know that it is not always reversible. Therefore there is something wrong with the theory.
neil - I am sorry but your information seems like a complicated jumble of this, that and the other. What are you trying to explain?

On May 28, 2014 at 11:36pm
Oscar Ormond wrote:

Dear Neil

The material in the plates is made of crystals. Lead metal, lead dioxide, lead sulfate crystals. These materials are either totally insoluble in sulfuric or almost totally insoluble. It is not difficult to discharge a battery in less than one hour. The materials are reacting chemically and the chemical reactions are happening very quickly.

Why does lead sulfate, the most soluble out of the three materials, suddenly become shy and refuses to cooperate? Give me FACTS.


On May 29, 2014 at 3:14am
brian wrote:

You don’t even need to spend money to check out a desulfator.  This listing on eBay for a desulfator 251541072272 offers to refund your money and the return postage if it does not work.

On May 29, 2014 at 4:14am
neil wrote:

Ok, I will offer something for consideration. John Fetter mentions Ostwald ripening. If you look up the wiki on this you get some good info, but you still have to make sense of it for yourself. Here’s a take on the sulphate crystal. (Crystal ‘chemistry’ is complex and has different stages or phases - you just haver to educate yourself about that if you want to know that depth). Anyway, the ostwald ripening, just because something is difficult to dissolve does not mean it can’t nor does it mean it won’t do anything significant. As an aside, you should take a look at solder and solder joints - here whiskers of metal grow across mm gaps and create short ccts in electronics - interesting that it usually involves lead solder! Or is lead added to reduce them? I forget. Anyway from a closed mind point of view, you try telling someone about whisker bridges of metal crystals or crystaline, growing from a blob of a solid metal solder joint in open air ! The battery chemistry/pulse idea is child’s play compared to that leap of failth (until you see the pics and throw the faulty electronic item away). It would not surprise me if you now tell me that you get that metal crystal whisker idea but are not convinced by the resonance/pulse idea, contrary as human nature is. Still has happened to me, I get a particular complex idea almost instantly, but for some time just cannot get my head around a simple idea. Then when I get it I feel stupid and wonder why it took so long - so then grows patience and compassion for others, like a crystal.
Anyway there seems to be a point of sticking on the fact that lead sulphate is almost insoluble in sulphuric acid, so how can it grow crystals out of such weak solution? Well, I have no problem when I mini down to sulphate crystal size and imagine what is going on around me. At that interface of the electrolyte/electrode there’s a lot of chemistry going on along with thermal stuff, like dissolving of lead sulphate. ion exchange (self discharge),  impurity effects. (did you know that the long life batteries, like those designed t live or rather guaranteed, for 15 yrs, use ultrapure lead). So I can even accept the physical migration of crystal molecules, rearranging themselve, creeping from one place to another, almost walking, so to speak, without ever becoming properly dissolved!
The big point in all this is that under normal charge discharge the built up deposit of such unwanted crystals (they are differnt from the useful charge/ discharge crystal form - small bobbly stuff) is not diminished, whereas with some pulse device, there is extra energy/vibration/resonance that is able to ‘knock’ them out of the unuseful hard lattice state to put them back in the chemistry loop.
You might find this link interesting.

On May 29, 2014 at 4:20am
shawn wrote:

john, as discussed before….why do heavily aged lead acid battery ‘positive’ plates turn a darkish black color, when the suspect culprit (Lead sulfate - hardeneing) is a whitish crystal?  Sometimes referred to as positive plate errosion - grid growth - etc… Smaller lead sulfate crystals and larger surface area does matter for the reversible reaction.  It is the non-reversible by products (i.e. lead dioxides, 3BS and possibly 4BS) that come out of solution during discharge based on uneven local ionic fluxes and the resultant alkalinity shifts within the micropores of the electrode that is the problem.  You are chasing the wrong rabbit down the wrong hole

On May 29, 2014 at 4:22am
neil wrote:

http://www3.alcatel-lucent.com/bstj/vol49-1970/articles/bstj49-7-1305.pdf. It alerts the mind to the fact that all is not as simple as it seems and there’s a range of chemistry/physics stuff going on…

On May 29, 2014 at 4:31am
neil wrote:

Hi Shawn, just to correct myself may28, I wrote increase reaction time when I meant increase reaction rate, as your technology enables. When will your web site be up again?
Kind regards

On May 29, 2014 at 4:56am
Shawn wrote:

Neil, site will be up in a few weeks.  I think you are talking about Tin Whiskers and believe this is a result of less lead in solder, it is a big problem and tough to understand basis.  also, RE: insoluble .... Yes, it appears as though many of the statement hinge on the solubility of the lead sulfate crystal…..that puzzled me in past until I took into account the dependency of solubility on PH conditions.  if one assumes that the PH is constant and uniform throughout the cell and within its pores, and equal to that of the electrolyte bulk PH then I can see why solubility is a confusing and misleading consequence.  Once one investigates the effects of PH on solubility, of not only lead sulfate, but other reaction products such as lead dioxides, 3BS and 4bS, it will help them understand the real root cause of our issue.  it is the interaction of these by products, in unexpected local alkalinity disturbances/conditions with the ionic lead sulfate reaction product that is reaping havoc on the electrode systems efficiency and cycle life. Of course, there are other physiochemical process also at play however they are minor in comparison (relatively speaking).  Now that our society is requiring much more rigorous and longer duty cycles (i.e. 24 and 72 hours and PHEV/EV) the true root of the problem will surface and be better understood.

On May 29, 2014 at 5:47am
John Fetter wrote:

Shawn - Positive plate sulfation is easily reversible. Simply charge the battery. Positive plate corrosion is unrelated to sulfation. It is caused by (persistent) high charging potential.
Alkalinity occurs in deep recesses. (It has been described as responsible for the condition known as “open circuit”, that affects lead-calcium.) Desulfation enthusiasts insist that sulfation occurs on the surfaces.
Desulfation merchants know that they must insist, rightfully or wrongfully, that 80% of batteries become sulfated. If not, they would have nothing to do.

On May 29, 2014 at 9:00pm
Shawn wrote:

It appears as though all reference to BatteryVitamin threads were removed, do not understand why.  john, tell us more about your magic pill for batteries

On May 29, 2014 at 11:15pm
John Fetter wrote:

Shawn - I believe Neil was using Inappropriate language. I can’t explain more about something that I do not have or do.
This is a technical forum.

On May 29, 2014 at 11:39pm
Shawn wrote:

john- tell us how BatteryVitamin L makes it better

On May 30, 2014 at 1:09am
John Fetter wrote:

Shawn - By far the best way to get hold of that information, I would suggest you go back to your source, read all about it.

On May 30, 2014 at 3:02am
neil wrote:

Hi Shawn, it does appear that Battery Vitamin has a lot of technical and semi technical write-up and that much of it has appeared on this thread and the other threads on batteryuniversity in various comments, verbatum.

If I was inappropriate I apologize - I was just shocked to learn that fact, which has subsequently been denied.

Full disclosure - I am not linked to or have shares or any connection whatsoever to any manufacturer of battery products of any kind.
The pulser circuits I tried I bought in kit form and assembled myself and tested with an oscillosc ope to make sure they were working.. They were from ebay, a company in the uk -Courtiestown Marine Ltd. I emailed them to ask a question about the cct, how to make the automatic cut off cct cut off at a lower voltage - I found they cut off at 12.5v - I thought it would be ok to cut off at a lower voltage. They were very helpful. In a reply they also mentioned that their sales had gone down drastically, suggesting people might be getting their pulse ccts from china, cheaper. I did not follow this up.

The BATTERYVITAMIN site suggests very strongly that the report of 80% death of car batteries due to sulphation is a ruse by the desulphtion merchants that sell a competitive product to Battery vitammin. BV suggest that the batteries die for a variety of reasons but 80% of the time seen as sulphation because they sulphate after they have died for a different reason. I can see a possible logic to this but think that those gathereing the statistics would have done so in a way that elliminated this possibility.

I too would like to know how the Battery Vitamin product works - I read about it but didn’t really understand. If anyone finds out or knows, I’m all ears (or eyes) (john?)
If I understood more I might give their product a try but I’m not sure how they sell stuff
Am I right in thinking that BatteryVitamin suggests that 95% of the battery failures are due to positive anode corrosion or such? Could this be true?
If that is true, then I want to do something to protect my batteries from this. I have four new batteries - two brand new from halfords, their liesure 115AHr (made by Yuasa) and two others carbon technology batsol or some such, they are ornage topped and sold to me from dublin with a five yr guarantee - since gone out of business in dublin - I need help with learning about that stuff. Sulphation and pulsing I get as far as I’ve gonet, but corrosion of the anode is something that I can’t get my head around.

On May 30, 2014 at 6:01am
shawn wrote:

John - i have reviewed and cannot seem to separate fact from opinion.  What is the fundamental basis and mechanism which makes it work?  How is it different from other battery additive technologies, or different from adding carbon, antimony, Ca, etc,,,?  If it only takes an additive why don’t the manufacturers add it to the battery during that step in process?

On May 30, 2014 at 7:22am
John Fetter wrote:

Shawn - Re your last sentence: They do.

On May 31, 2014 at 4:19am
neil wrote:

Shawn, it is telling that john has had so much to say on all manner of battery topics on this site, but when asked about the Battervitamin solution, has nothing to say. I have asked him many questions now that he can’t won’t or avoids answering. This is a shame because he seems to have done a lot of experiments with lead acid batteries.
I’ve been reading on nickel iron batteries, is there a good forum anyone knows of for that topic here or elsewhere?

On May 31, 2014 at 5:24am
John Fetter wrote:

Neil - The reason is simple.
This is a technical forum, not a commercial forum.

On May 31, 2014 at 6:07am
neil wrote:

All my questions are technical in nature about the stuff out there that people are trying and buying.
Just because I mention Batteryvitamin, does not make it a commercial question, I ask what it is and how it works because I don’t understand their own explanations of what is going on. You are a technical guy with lots of experiments under your belt. You have knowledge of all that’s out there pretty well. I’m sure you know about batteryvitamin and could share what it is and how it is supposed to work in a way that those on this forum, me included, might better understand. Indeed you knwo that battery manufacturers add it to their batteries. I have spent nearly 400 on batteries recently and I’m open to any preventative maintenance solution that will save me having to spend 400 in two to five years time. I am worried about anode corrosion now, thanks to your alert and claim that it effects a lot of batteries. I care not about the commercial side. I use my technical understanding to decide/choose what to do. It has its limits whih is why I’m on this forum to learn more.

Are you now withholding information/experience/explanation to punnish me for challenging you or daring to support/discuss the desulphation with pulsers idea

“this is a technical forum, not a commercial forum’ is a meaningless fudge response to genuine question (technical in nature) asked on this thread.

I thought you were bigger than that

On May 31, 2014 at 7:07am
John Fetter wrote:

Neil - if you want to know how something works, and there is a website with more than 20 pages with detailed technical information, stands to reason that by reading those pages you will probably find the answers.

On May 31, 2014 at 8:07am
neil wrote:

Like I said I thought you were bigger than that.

u good at evasion

You really dont seem to want to answer anything except to put down down other competitive technologies.  mmmm

On May 31, 2014 at 8:56am
John Fetter wrote:

Neil - Let me try this again. Go to the website. It will tell you what you everything you want to know.

On May 31, 2014 at 8:59am
John Fetter wrote:

What you want to know, everything you want to know and perhaps more than you want to know.

On June 4, 2014 at 3:34pm
Nehmo wrote:

Neil, Shaun

John Fetter suggested that you can get you answers on the Battery Vitamin website. I am curious. You say you’ve looked.  Well, I have looked as well. What is the problem? Can’t you two read?

On June 5, 2014 at 2:25am
John Fetter wrote:

There are between 500 and 800 automobiles per 1000 population in the countries of the so-called developed world. In other words, nearly one lead-acid battery per person.
A US battery industry magazine, (ceased publication about ten years ago), The Battery Man, carried BCI figures for US shipments of original equipment batteries and shipments of replacement batteries. These showed that about two out of every three golf-cart batteries shipped are replacement batteries, three out of every four automobile batteries shipped are replacement batteries and that the figures seem to show that 100% of leisure boat owners are replacing their batteries at least once a year. These BCI figures show that the longer batteries are left unused, the greater the rate of replacement. This appears to be reliable, non-anecdotal evidence that sulfation is very common and is caused by neglect.
If we focus on the figures for automobile batteries, it should be self-evident that, from a business point of view, if battery desulfation technologies work, the battery replacement sector should be next to non-existent as a result of competition from the desulfation sector.
We know that the battery replacement sector is thriving.

On June 5, 2014 at 6:50am
neil wrote:

Hi Nehmo, john, the last arguement is falacious and disingenuous.
1st point when a new idea (which may not be that new - but is new to those curious about, say desulphation) is gaining a presence, as sulphation is on the internet, those interested and curious will look for info. Perchance they may land on batteryuniversity site and be told by john fetter that it does not work, never worked, is a scam, blah blah, even that there are 70 patents for (pulse?) desulphation that do not work, are nonsense, blah blah. (he does contradicti himself in two or three comments where he says pulse desulphation does work!). So this is going to drive people off the idea, rather than risk a few quid and try it for themselves. This helps the battery replacement sector and other sites like batteryvitamin to gain business, to mop up those turned off pulse desulphation. Market competition, disinformation, confusion - desulphation is up against the likes of john fetter’s hatred for the idea and his doorman position on this site putting all those coming throught this door looking for good info/help completerly off the idea.
2nd Do Nehmo or john actually know how batteryvitamin actually works to save the battery. BV site only goes so far and john knows all about all battery issues so he was asked if he knew if he could explain a little bit deeper into the chemistry. So all we get as an answer is go to the site, read it, the explanations are above for all to read. And you Nehmo, all you have to offer is ‘can’t you read?’ Thanks, you advianced the understanding so much. I suspect this site is a subtle scam, with doorman bouncer john fetter from Battery Vitamin, making sure people stay away from desulphation ideas and solutions. Even the paragrahp above he quotes from the BV site. He will delete this post too, can’t help himself.
kind regards

On June 5, 2014 at 7:38am
John Fetter wrote:

Neil - A thousand and one desulfation treatments have been announced over the last 100 years and there is overwhelming evidence that not one has been successful. This is how one recognizes success. Invention followed by prototyping, field trials, marketing launch, sales, business thrives, etc. That is all I am saying. If you have a brilliant new idea, that is wonderful.

On June 5, 2014 at 1:32pm
Nehmo wrote:


Many words, few facts. Please stop whinging. We want to know about your technical ideas, not you emotional issues.

On June 5, 2014 at 1:38pm
neil wrote:

Now who can’t read, nehmo?

On June 6, 2014 at 12:59am
John Fetter wrote:

Desulfation is an interesting subject. I am not trying to promote anything. I am not trying to denigrate anything. I have been trying to find out whether desulfation works and is misunderstood; or whether it simply does not work at all. There appear to be two components. The obvious being technical and the other that must be taken into consideration being the human angle.
It is virtually impossible to decipher the technical intricacies. There are far too many theories and systems.
People who find desulfation stimulating and attractive tend to be clever, dedicated, focused. However, many appear to be absorbed in the subject to the exclusion of other important factors. It is as if they are intent on working by facing what they enjoy and keeping the things that they do not like behind them. They do not like tasks that require concentration, like reading lengthy articles. It appears there may be a name for it. Attention deficit.
The only way I was able to find an answer was by analyzing the commercial impact, or lack of impact, of desulfation.

On July 13, 2014 at 9:00am
Howard Phillips wrote:

Contact info please for John Fetter?  Kind regards, Howard Phillips hp@valliant.net

On July 13, 2014 at 9:07am
Howard Phillips wrote:

John Fetter— I’d like to discuss new theory describing how and why some solid state batteries last a long, long, long time, and recharge themselves with no need for a battery charger.  The new theory I would like to discuss with you emerges from solid state physics and is based on very fundamental knowledge and established solid state theory.  By way of introduction, my background is online at www.Phillips.8k.com   I know your background is electronics and battery engineering—a perfect fit for the discussion I’d like to have with you.  Kind regards, Howard   hp@valliant.net

On July 13, 2014 at 4:28pm
John Fetter wrote:

Howard - I would be happy to discuss although I should point out that I am having some difficulty visualizing batteries that recharge themselves.

On July 13, 2014 at 5:25pm
Howard Phillips wrote:

John Fetter—Yes, it is indeed a new concept.  I believe there is definitely something here, and that it is a previously-unexplored area of science.  But, I’m not 100% sure that the new theory is correct, and that is why I choose to discuss this with people (perhaps you) who have more battery experience than I have.  I am not a battery engineer, so please think of me as someone bringing this theory to you from the field of solid state physics.  I like your comment, “Howard - I would be happy to discuss although I should point out that I am having some difficulty visualizing batteries that recharge themselves.”  What I am looking for is a very knowledgeable skeptic—but an open minded skeptic.  Can you email me with better contact info—perhaps your Skype address or perhaps your telephone number?  Kind regards, Howard

On July 13, 2014 at 5:27pm
Shawn wrote:

john, will certainly give you an un-biased opinion

On July 30, 2014 at 11:11pm
saman wrote:

hi, John Fetter .
To get 200mA charge you need to put something around 1000W in series with the 12v battery charger - The 60w bulb will give you only about 8mA .  Remember V = Ix R and W=V x I , (

On July 30, 2014 at 11:27pm
John Fetter wrote:

saman - You are supposed to put the lamp in series with the AC power input to the charger.
(As a matter of interest, the filament resistance of an incandescent lamp falls by roughly an order of magnitude from fully lit down to near-zero brightness at 12V. Your V = IR calculation would not work anyway.)

On July 31, 2014 at 4:19pm
Tim W wrote:

Interesting discussion!

On August 4, 2014 at 12:39pm
Josh B. wrote:

What is your guys opinion on making a brand new lead acid battery last longer? Specifically a 36v 12ah deep cell battery. I also live in California and heat is also a constant problem. The battery is for a electric scooter I plan to ride every day in mountains. Any tips are appreciated. Thanks guys.

P.S. I’m not exactly a battery expert so please answer in English ^.^

On August 4, 2014 at 2:32pm
Chris C. wrote:

Josh, I would strongly discourage you to use a lead acid battery for that purpose because of weight - and use the plentiful 18650 lithium ion battery in packs instead, it has a much greater energy density and can be cheaply salvaged from surplus or otherwise depleted laptop battery packs

Check this out… https://www.youtube.com/watch?v=Z-VLdE6RxYQ

If you already purchased the battery, keep it charged, discharge it as little as possible, keep it from overheating, keep the demand low (typically 1/10th current drain of the battery capacity), keep the the cells filled, topping up with distilled water as needed, and monitor the electrolyte density of each cell to be the same and equalize the cells that are under by overcharging occasionally while keeping an eye on electrolyte level and refilling those cells that are drying up in the process.

Hope this little bit helps, but you should really read up on this to understand the fundamentals.

On August 4, 2014 at 6:51pm
Josh B. wrote:

Thanks for the advice!
The battery is actually 3 smaller batteries all linked together, it’s 30lbs (more wight more battery life right?) the company sells Lithium ion batteries for the scooter but it is very expensive ($500). The scooter would be used with a 1000w motor. ~4 miles in very hilly terrain so I would assume it would use quite a bit of power. The company sells a desulfator & speed charger but I myself don’t know much about it, they claim that it can double battery life. I’m looking for solutions that don’t involve opening the battery and are either low cost or well worth it. Any advice, even something that seems obvious to you “pros”. The only thing is that keeping it out of heat is not always possible. Thanks again

On August 4, 2014 at 7:48pm
Chris C. wrote:

You should have a good read on the right battery for your application,  there is one right here http://batteryuniversity.com/learn/article/whats_the_best_battery that could give you some good basic info on the subject.

As for Li-Ion, custom built packs are expensive because of all the externalities: small market segment, custom cases and circuitry, liability, etc. A home built battery pack is doubtless going to be a fraction of that.

36V at 12Ah makes for a total capacity of 432 wh, which is about the total amount of power a top shape cyclist produces in one hour. a 1000W motor would be adequate for the job no doubt but it would run down the battery pack in 1/2 hour, when it should be running it down in 10, not good for longevity.

OTOH, a Li-Ion battery pack can be built in many different configurations (heck you could probably make it fit between the frame and the pedal) and programmable, can easily withstand high loads (they are routinely charged and discharged at C rate, contrarily to lead-acid which require C/10 to survive any length of time) and automaticv, equalizing Li-Ion chargers can be found inexpensively online.

Considering decent, 8wh li-ion batteries (2000mAh at 4V) can be had for as little as $2 each in quantities, 100 cells would cost $200, have twice the capacity of the lead acid for a third of the weight and considering its performance under high load conditions it’s easy to see why it’s the better option here.

In other words… No doubt Li-Ion is better for your application, it’s simply a matter of figuring out whether to purchase the pack or get into the adventure to make your own.

On August 4, 2014 at 9:55pm
Josh B. wrote:

Woah, thanks!
Li-Ion is most certainly a better choice. Any idea where I could pick one up? Also say I kept the Lead acid one that came with the scooter? Any simple pointers to prolong battery life? I wouldn’t be able to get a li-Ion battery until later but I will consider that. Only $200? Btw it is a 1000watt DC 36v 2750 rpm motor if that makes any difference to you. I don’t have it but the battery looks like 3 car batteries in a series to make up a big 30lbs, 36v 12ah deep cell battery. (looks like, but isn’t actually 3 car batteries) the scooter goes up to 25mph and it’s range on a full charge is 10-18(obviously depending on the speed and terrain driven on)

Thanks, you are so knowledgable :D

On August 4, 2014 at 11:30pm
John Fetter wrote:

Josh - The simple answer to your question. Try not to use the bike and afterwards leave the batteries discharged. Always give recharging priority.
Do not speed charge. Do not pulse. Simply recharge.
Chris - As a matter of interest, the lead-acid battery in every car is discharged many times per day at 10C to 20C. Starting the engine. The reason why it is there. There are 1 billion car batteries in use world-wide. It would seem fairly common for lead-acid to successfully undergo very heavy discharging.
I agree, it would be nice to use Li-ion but it seems one needs the right connections.

On August 5, 2014 at 9:12am
Josh B. wrote:

So every time after I use it, make sure I plug it in and charge it fully. I will try to make sure it is stored in a cool area as well. Sulfur crystals start to form when the battery is discharged right?(so the sooner it’s chargered the better?) Should a “Smart Charger” can be left overnight when charging lead-acid batteries? Anyways, Thanks for the tip. Much appreciated!

On August 5, 2014 at 3:13pm
Chris C. wrote:

Josh: I concur with John regarding the importance of recharging immediately, because the worst enemy of a lead acid battery is the lead sulfate that results from the discharge. If it is not recharged immediately, it tends to grow into crystals that are extremely hard and sometimes impossible to revert back into lead and sulfuric acid. Excessive discharge of lithium-ion batteries also destroys them and can even make them dangerous to reuse, that’s why most 18650 cells found in most consumer products have circuit boards in them that cut-off the cell when voltage drops below 2.5V.

It is therefore paramount to recharge both lead acid and lithium ion batteries immediately after use, the sooner the better, which is the opposite of the old nickel cadmium or nickel metal hydride battery.

There are small but important differences, though. Lead acid batteries crave a full charge and can sustain an overcharge under controlled condition (no excessive temperature and topping up cell electrolyte as it evaporates during the overcharged typically used in the process of equalizing battery cells, for example) and self discharge very quickly, whereas Lithium Ion batteries will not tolerate surcharges at all (which can destroy them) and actually prefer a lesser charge for longevity (for example charging to 4.1V instead of 4.2V) and can stay charged for sometimes years and are usually shipped with a half charge precisely for longevity, something which would quickly kill lead acid batteries.

John, I agree that lead acid batteries can give enormous amounts of current, but not on a sustained basis as described by Josh (4 miles of mountainous terrain, presumably taking out most of the battery’s capacity in an hour or less) with a size of battery that is manageable for a light vehicle. Unless, of course, I am mistaken as to what a ‘scooter’ is and what the hilly terrain is like. In any case, it is quite different moving objects on a flat terrain like in a factory or on a gold course for a short while, where batteries have thousands of amp hours of capacity and typically don’t run for extended times, or if they do,  such as with troll marine motors, with batteries sized accordingly (a small fishing troll motor uses typically about the same amount of power as Josh’s electric motor, but the batteries used weigh typically 100 to 200 pounds with several hundred amp hours of capacity).

Finally, Josh, as for leaving a smart charger on your lead acid batteries, I don’t see why not as long as it is designed and sized for the battery type and size you are using (flooded, gel or AGM).

On August 5, 2014 at 10:21pm
Josh B. wrote:

Great, thanks for answering my questions guys. In case you were wondering, the scooter, looks and is similar to a razor electric scooter, having two wheels, a floorboard and a seat. But it is way different as far as specs and with the 30lb battery, it weighs 90lbs. So yeah, it’s heavy. But I weigh 135lbs so that will help it. (I’m 14) Also with the trolling motor comparison, not all batteries need to weigh that much. In a small boat in a lake at my friends house we use a 30lb thrust (don’t know the wattage of it) trolling motor and hook it up to a car battery. It takes us around the lake all day, but while fishing it is turned on and off so the battery isn’t constantly being used. The boat is a metal(aluminum) fishing boat with bench seats, I can imagine on big fishing boats that the batteries weigh 100-200+ pounds.

On August 20, 2014 at 12:16am
tahir wrote:

my new vrla battery body has been cracked can it be repaired?

On August 20, 2014 at 2:26am
John Fetter wrote:


On October 6, 2014 at 11:09am
Marcus wrote:

I have what appears to be a starter battery sulphation case; and wanted to pass along a couple of observations from my 24 hour 16v-overcharge reconditioning experience thus far.

I have a cc/cv benchtop power supply which has followed a bell-curve during the process; ie: starting from max current @ terminal v tapering down to a nadir of around I/2 after 7hrs; now ramping back up steadily as the last 8 hours’ charging process completes.

To the uninitiated, this would seem to indicate the possibility of desulphation occurring: Any input regarding this type of curve while reconditioning a starter battery?  Is there a rule-of-thumb concerning a process termination point based upon the observed I curve?

Thank you.

On October 6, 2014 at 5:13pm
John Fetter wrote:

Marcus - My take on your experience is that your battery was simply discharged. Your battery reached full state of charge quickly, suggesting a high charging current. The charging current was high enough to heat the battery. The current began to taper towards full state of charge. The battery reached full state of charge but the current was high enough to keep increasing the temperature of the battery, therefore the current climbed up again.
If a battery is sulfated, it won’t take much current at commencement of charging, even if the voltage is increased to 2.8 volts per cell. The current may begin to climb slowly after some time, reaching a peak after quite a few hours, then tapering towards end of charge, the reverse of what you observed.

On October 6, 2014 at 7:55pm
Marcus wrote:

Thank you, John, for the insights.

Just finished the process a few minutes ago; and the battery seems to have dropped quickly back towards nominal OCV.  Closure saw things at a touch over 3A, 16.0v; with virtually no electrolyte loss across the cell bank.

Of side note there was, indeed, some of the behavior you mentioned which initiated my investigations and work here: The unit would not take a proper charge using a switch-mode auto charger; and it would not crank over after a cool early-Fall evening.  All connections were tested and good.  However, when the linear lab supply was implemented, things started happening rather quickly at around 14v or so…

At any rate (no pun intended), hoping for a better result in the vehicle tomorrow morning.  Looking for a few more turns with the investment here wink

Thanks again, and good night.

On October 6, 2014 at 11:16pm
John Fetter wrote:

Marcus - The best way to charge a lead-acid battery is with a taper charge. Using a cc/cv power supply, setting the current to 3 or more amps, maximum potential at 16 volts, causes the battery to overheat. You would be pumping 48 watts or more into a fully charged battery.
An ordinary high reactance transformer - rectifier charger probably provides an ideal taper charge.
I suspect you could parallel two cc/cv power supplies, set the one to 3A, 14.4V and the other to 250mA, 16V.  You would obtain a 2-stage charge that would not overheat the battery.

On October 7, 2014 at 8:07am
Marcus wrote:

Good day, John.

Well, we tested @ 8+h later; and still at nominal OCV.  Apparently there are no large internal shorts; and the vehicle was happy with its renewed source of power.  BTW, good idea for a taper-type charger setup using this type of equipment.

However, I do confess to some confusion over the emerging I-E relationship here: Is potential not the governing factor in operations such as this, or should we be looking to an unlimited potential protocol with a (rule-of-thumb) constant current level, concluding with process termination at 16v?

Thanks again.

On October 7, 2014 at 9:39am
John Fetter wrote:

Marcus - A battery on charge must be treated as an electrochemical device, not a passive load. It will commence gassing at 2.35 volts per cell. The objective is to get it to accept as much energy as possible before it reaches gassing potential. Electrolysis is not efficient hence the battery will get hot if the current is not reduced. Heat can damage a battery. A taper charge solves this problem. Do not hold a battery at 16 volts for too long. It will turn into an electroplating bath and metal will be corroded out of the positives and end up plating onto the negatives. Eventually a cell will short out or the positives will collapse. An automobile alternator regulator typically presents the battery with 14.2 to 14.4 volts. Fractionally above the onset of gassing.

On October 7, 2014 at 10:22am
Marcus wrote:

Thank you again, John, for the helpful information.

You mentioned,

“Do not hold a battery at 16 volts for too long. It will turn into an electroplating bath and metal will be corroded out of the positives and end up plating onto the negatives.”

So, if I might, I’d say I’m still a bit confused with regard to the original context (sulphated-cell reconditioning).  From BU-804b:

“The battery terminal voltage is allowed to rise to between 2.50 and 2.66V/cell (15 and 16V on a 12V mono block) for about 24 hours. Increasing the battery temperature to 50–60°C (122–140°F) further helps in dissolving the crystals.”

(Of side interest, cell temperatures stayed at or below 50°C for the entire process duration.)

Now, the foregoing advice is offered in the context of a 200mA current level.  So, the matter which remains a bit foggy to me is whether or not I or E governs in a sulphated-cell 24h reconditioning scenario; as I will vary on the basis of present sulphation level, plate area, temperature, etc.

Thanks again—

On October 7, 2014 at 10:43am
Art Schultz wrote:

I was just about to comment on temperature when I read Marcus’ question on temps. I live in a perpetually cool climate, so my typical battery temperature for most of the year would be maybe 40°F. I have been using a CC/CV power supply in CV mode to equalize rather large 8D size batteries. Starting at 15.8V, I might get 11 amps, quickly tapering to less than 2A. The action inside the cells is usually minimal, so I have been cranking up the voltage until I see more activity. I’ve done this maybe three times now where I have ended at 16.7V with a bubbling action like a recently poured soft drink. The cells are gently fizzing.

It is important to note that I do not walk away from the process while cranking up the voltage. I have not gone past 4 hours for the whole process, regardless of the results, due to some concern about the over voltage. I understood the most important part to be a steady gentle bubbling, not some maximum voltage. I would need to work very hard to overheat my batteries in any season, so that will never be a concern for me. Now you worry me with that warning never to go past 16V. I really hope that is a temperature dependent number that mostly applies to warmer climates.

On October 7, 2014 at 4:32pm
John Fetter wrote:

Marcus - Your battery was not sulfated.
Much of what has been said about sulfation for the last 100 years has been made up to persuade people to buy things that they don’t need.

Art - If you are equalizing the battery and it is warm to the touch, it is fine. If it feels hot enough for you to want to take your hand off the case, you’re damaging the battery.

On October 9, 2014 at 9:01am
Marcus wrote:

I don’t quite understand what is happening.  With all due respect, I have no interest in whether my particular battery was sulphated or not; nor am I presently interested in purchasing battery-conditioning equipment.

Therefore, is there anyone who can address the following question directly:

Does I or E govern during a 24h desulphation protocol in accord with this central quote from BU-804b,

“...reversible sulfation can often be corrected by applying an overcharge to a fully charged battery in the form of a regulated current of about 200mA. The battery terminal voltage is allowed to rise to between 2.50 and 2.66V/cell (15 and 16V on a 12V mono block) for about 24 hours. Increasing the battery temperature to 50–60°C (122–140°F) further helps in dissolving the crystals.”

For if E governs, then the preceding in-context statement concerning I,

“reversible sulfation can often be corrected by applying an overcharge to a fully charged battery in the form of a regulated current of about 200mA”

is not widely applicable; as Icharge @ 16v. in relation to any particular battery construct/condition sceanrio will vary widely based upon a whole number of attending factors.

Speculatively, if E governs, is there a third (undisclosed) parametric consideration which would affirmatively indicate process termination before the 24h mark; ie cell temperature, specific H evolution volume, etc? 

Is there someone who can provide clarity and insight concerning these aspects of the protocol disclosed in BU-804b?

Thank you.

On October 10, 2014 at 4:49pm
John Fetter wrote:

Marcus - The lead-acid battery has been an item of commerce for 130 years. Lead-acid batteries wear out. Naturally, there will be people who will try selling remedies. The situation is simple. Caveat emptor.
To answer your question, does E or I govern the protocol: They reach a state of equilibrium at the conclusion of the process.

On December 27, 2014 at 12:57pm
Tim wrote:

John Fetter wrote: “stationary batteries are not considered suitable for deep cycling”.  As this was in response to one of shawn’s posts, I’m pretty (but not 100%) sure that he meant the opposite.  That said, motion and vibration in mobile applications may be conductive to mixing and thus reduce stratification… so there may be a grain of truth to the statement.  Anyone care to shed some light?  Does regular equalization provide sufficient mixing of the electrolyte to avoid stratification in stationary, deep-cycle batteries?

On December 27, 2014 at 7:50pm
Chris C. wrote:

Tim, to answer your equalization question - the answer is YES.

That being said, all the bubbling caused by electrolysis especially from the already fully charged cells can also cause active material shedding, so you’ve got to be careful and limit current intake during equalization to approximately C/10 - C/20 and monitor battery temperature. Voltage is irrelevant (except perhaps for any connected electronics)

I’ve been equalizing the marine batteries in my truck for over a decade now and I wouldn’t charge my batteries any other way. Equalizing allows to counteract the weak link phenomenon that can severely limit a battery’s output and can prevent premature battery death due to sulfation of a single cell.

On December 27, 2014 at 8:38pm
shawn wrote:

John, good question….what frequency and amplitude to you suspect these mechanical vibrations are at?  I believe they seismically qualify typical 12VDC lead acid batteries in cars to withstand ~130Hz….but that may have changed.

I have seen the term bubbling used here ans was wondering in what context….the bubbling induced by electrical transients or induced by actual ir bubbling systems that th Nvy has been doing for 40+ years.

It seems like this site i full of pieces but no real meat or conclusions.  I still want someone to answer why significantly degraded and aged lead acid plates have a blackish tint when PbSO4 is a known whitish substance?  I am not able to nail this down nor i have i been able to invalidate my understanding of the fundamental basis of this phenomenon.  I would really like to get into some serious discussion but not sure this is the right forum…if you think otherwise lets talk.  I am quickly moving into Li-ion area but my main interest remain ion lead acid

On December 28, 2014 at 11:37pm
John Fetter wrote:

Tim - What do you consider a stationary battery? Do you consider it a battery that remains in one particular place and is not moved around?
Lead-acid batteries are made broadly in three different categories:
  Automotive, general purpose;
  Stationary, standby;
  Motive power, deep cycling.
A stationary battery is purpose designed to be operated on float continuously. It can be cycled only a few times during its lifetime.
A deep cycling battery is purpose designed to be discharged and recharged repeatedly.
When a battery is called upon to deliver a heavy current for a comparatively long time, the acid nearest the plates becomes depleted. This effect can be countered by agitating the electrolyte, for example, by air injection. When water is added to the electrolyte and the electrolyte is not agitated, for example, by gassing the battery, it results in stratification. Equalization helps to balance the cells and helps to mix the electrolyte.

On January 9, 2015 at 3:52am
bertie wrote:


If, as is claimed, desulfation removes a layer of white sulfate that forms over the battery plates, why don’t the makers of desulfation products provide straightforward evidence - a time lapse movie showing a test battery in a transparent case undergoing desulfation?

On January 21, 2015 at 9:39am
Tim W wrote:


On February 14, 2015 at 12:17am
49thdiver wrote:

I think this is the video you might be looking for :
However from what I can see from this discussion, adding the fluid is irrelevant.
Topping up the fluid yes, but could be water and cycling the batteries is what is responsible for the improved specific gravity and the implication that the battery is recovered, ie has restored capacity

On February 14, 2015 at 12:35am
49thdiver wrote:

John, thanks for this sustained conversation. I have just acquired 18 used 6 volt deep cycle lead acids to use for continued testing and development of my electric vehicle project.
They came out of an actively used EV, the owner has been experiencing reduced capacity but has also been having difficulty with charging. The vehicle charger failed and he was reduced to charging batteries two at a time, it looks like a poor charging situation contributed to degraded performance.  He also did little or no fluid maintenance.
I will tomorrow be checking voltage, fluid and specific gravity. I am prepared to conclude that getting the maintenance in order, cycling the batteries and over charging the batteries at 200ma to 7.5 or 8 volts per battery might bring the batteries in to the most optimal situation for the age and condition that they are.
Please advise if you agree or ?
Question 1. You may be familiar with the simple capacitive fed bridge rectifier chargers that are out there (see link below) is this a good way to “over charge the batteries for a maintenance cycle.
Question 2. I have seen situations where people are charging battery using the above technique one at a time (12volts) and others that charge all the batteries (8X12volts at or 96volts) the same time, which would you recommend if you thought that a maintenance cycle like that was beneficial and how often would you do it.

Thanks again for the conversation

On February 14, 2015 at 2:32am
bertie wrote:


The movie begins with a near-new transparent-case battery, that has been discharged, receiving some colored liquid.

The clamps indicate that something the size of a welding power supply is being used to charge the battery. The volume of gas coming off the top lead indicates that between 100 and 200 amps is being pushed into the battery. The plates accept very little charge while this is happening, borne out by the small increase in SG.

The battery is given a tiny amount of discharge and time to cool down and the process is repeated, several times. The temperature went up during the first charge because the internal resistance of the battery was at its highest.

Eventually the battery ends up with the SG that it possessed before the test.

The intent behind the movie is to mislead.

On February 14, 2015 at 12:07pm
49thdiver wrote:

Bertie, nice observations, indeed I had wondered why the temperature of the liquid was so high on the first test, that said overall the temperatures are certainly not normal operating temperature of a car battery. What would be the ideal ambient temperature for a SG test, I have not seen this noted anywhere, I will do a search but interested in your comment.
You are polite when you say the video is only misleading

On February 14, 2015 at 1:12pm
49thdiver wrote:

Bertie :
Temperature Correction
SG of acid is temperature dependent. If the temperature is very cold or very hot this can lead to incorrect readings. To correct for temperature use the following equations the equations or below 70ºF subtract points (0.03 per 10ºF) and above 70ºF add points.

  Correction factor = (0.331 x Cell Temp ºF - 23) / 1000 or 0.003 pts per 10 ºF

  Correction factor = (0.595 x Cell Temp ºC – 12.5) / 1000

This is valid for 0-130ºF or -17.8- 54.4ºC

This formula pulled off the web does not support a specific gravity change of the magnitude indicated in the video by temperature alone.
Found at http://support.rollsbattery.com/support/articles/4347-measuring-specific-gravity
Your thoughts ?

On February 15, 2015 at 10:13am
John Fetter wrote:

bertie - Red liquid, clear liquid, no liquid at all, would give the same results.
49thdiver - The SG temperature correction in the video is a red herring.

On February 15, 2015 at 11:51am
49thdiver wrote:

John, Indeed a red herring. Did you have any thoughts on my post above @ 12:35 on the 15th regarding charging and battery maintenance. I have now measured the SG in all the batteries and they vari from 1125 to 1200. I have load tested them to 100 amps with less than a 1 volt drop. I have built one of the chargers as above and charged now for the first time since aquiring them for 12 hours. I will continue testing today.
PS the cells look cleanr from the top of the battery and the liquid is above the plates.

On February 15, 2015 at 4:15pm
John Fetter wrote:

49thdiver - Charge a 6V golf-cart battery at no more than 30A up to 7.65V and hold at that voltage. The current should eventually taper away down to about 2A. When the current stabilizes the battery is fully charged. Then check the SG. At this stage a low SG does not necessarily mean a bad battery. Besides underfilling, someone could have overfilled in the past, causing the battery to overflow.
Capacitor + bridge works. It delivers constant current charge. Nothing wrong with the idea technically but it won’t stop charging and can electrocute the unwary.

On February 15, 2015 at 4:56pm
49thdiver wrote:

Very helpful, Thanks

On March 6, 2015 at 10:59am
ComonSense wrote:

Nothing that I would ever have to worry about. I bought a good battery and keep it at least 80% charged (which automatically happens if you operate a motor vehicle properly, meaning i. e. no short trips with large electric draws during winter time etc. etc.).

Both batteries in both of our cars are older than 5 years and just made it through another sub-zero winter.

On March 6, 2015 at 11:23am
bertie wrote:


My neighbor is careful to avoid trips under 20 miles and his batteries also seem to last forever. He travels ten miles, turns around and comes back, stops at the local supermarket just down the road, buys stuff, then comes back home. Works great in winter!

On March 22, 2015 at 6:11am
Andrew wrote:

My batteries in my cars last about 10 years.
I put them the Battery Fighter charger which is fully automatic, and fully charge them every weekend.
I also buy the batteries with the caps at the top, so I can keep the electrolyte topped up.
I got 8 years out of a battery once, felt so ripped off…...

On June 16, 2015 at 11:53pm
Jean Paul wrote:

After 20 hours charging, the battery voltage reading was 12.1 volts.  Does that mean that sulfation problem?

On June 17, 2015 at 12:16am
bertie wrote:

Jean Paul

No. Your battery has shorted cells. Buy a new one.

On June 17, 2015 at 2:19am
Jean Paul wrote:

short-circuited cell battery should give 0 volt when measuring

On June 17, 2015 at 2:44am
bertie wrote:

Jean Paul

A 12v battery has 6 cells. It is highly unlikely for all six cells to become shorted at exactly the same time. You seem to be getting a voltage of a 5-working-cells, one-shorted-cell battery. A healthy battery on charge, even a sulfated battery on charge, after 20 hours, will measure over 15 volts.

On June 17, 2015 at 3:14am
Jean Paul wrote:

Thanks. You are right.

On June 23, 2015 at 12:42am
Gavin wrote:

Bertie/ Jean Paul,

I’d actually say that with a voltage of 12.1V that the battery is exhibiting low charge acceptance, maybe a soft short is in there somewhere - but one lone cell will not be completely shorted.
It’s highly likely that there is some permanent sulfation which will give rise to a low charge acceptance, because the hard sulphate crystals are no longer ‘active’ material.
Personally I’ve never seen a battery measure over 15V, and if it did then i’d be worried about the state of it. Over-charging can promote grid corrosion and age the battery prematurely

On June 23, 2015 at 1:36am
Jean Paul wrote:

Hi Gavin,

How can we try de solve this issue if I suppose that there is some sulfation.

On June 23, 2015 at 1:42am
bertie wrote:


A proper battery charger will taper charge and will push the voltage of a good battery to at least 15 volts at a very low current. As soon as it reaches 15 volts, switch off. If you have never seen that, then you have never seen a fully charged battery.

The reason why batteries get sulfated is because they spend most of their lives just sitting around. They receive an occasional sip of electricity at a pathetic 14+ volts. They will never reach 100%, even if the car is driven non stop all day.

Sure, they get sulfated. They also short out due to plates warping. The cure is simple - prevention. Give the battery a proper charge now and then.

A niche industry has sprung up around pulse chargers. The makers of these things have no idea how batteries work. They tinkered with the most obvious idea, pulsing, and in many instances it worked. The peak voltage value and the low on periods are equivalent to a taper charge.

There is no corrosion if the battery is taken up to full charge and charging is then stopped.

On June 23, 2015 at 2:15am
Gavin wrote:

Sure the battery is charged up past 15V. You can charge up to 2.75V per cell therefore taking the voltage up to around 16.5V on certain charging regimes but it has to be charged correctly (with constant current and constant voltage phases), this high voltage charge should only last a short time as its an equalisation charge to make sure all cells become fully charged. But once the battery has settled after a correct charge you’d expect the open circuit voltage of a fully charged 12V automotive battery to be around 13.2V.
Charging at 15V+ over a long period can promote hydrogen and oxygen evolution (water loss - reduces service life in VRLA batteries) and grid corrosion. Grid corrosion on the positive can lead to grid growth and with the compact design of automotive batteries this can shorten the life by the positive grid growing up and contacting the negative strap/group bar. Also advanced grid corrosion means increased internal resistance of the battery leading to a reduced discharge voltage especially when discharged at a high rate (like when starting an engine!)

On June 23, 2015 at 3:31am
bertie wrote:


Repeat: There will be no discernible corrosion if the battery voltage of the battery on charge is allowed to rise to 15 volts and the charging is then stopped.

A battery that sits around most of its life, and is occasionally given a fraction over 14 volts, will die of sulfation and consequent buckled plates. Soft and hard shorts, low end of charge open circuit voltage.

Extraordinarily easy to prevent with an occasional lift up to 15 volts.

I am curious as to why do you believe it necessary to provide emphasis on the dangers of long term charging at over 15 volts after first asserting that you have never seen a battery measuring over 15 volts?

Are you in a desulfation line of business?

On June 23, 2015 at 3:43am
Gavin wrote:

Yes, I said I’d never seen a battery measuring over 15V ( I meant the battery OCV once the battery had settled after charge) a fully charged battery’s OCV should read about 13.2V after settling down after a charge.
Like I said voltages during certain charge regimes will rise to 16.5V.
Charging at 15V and over for long periods can be detrimental.
What do you mean by buckled plates as a consequence of sulfation?

I’m not in the desulfation line of business. Nice to see that you think anyone disagreeing with you has a hidden agenda.

On June 23, 2015 at 4:06am
Alice wrote:

Hi Gavin, Hi Bertie, Jean Paul already has his answer.

On June 23, 2015 at 5:06am
Gavin wrote:

Does he?

Really, without tearing the battery apart, this has all been conjecture anyway.

On June 23, 2015 at 9:20am
Vincent wrote:

Alice, Bertie, Gavin

I really don’t understand battery people. Why the complicated explanations? Surely one of you could have said, “look inside, that will explain it”, in the first place?.

On June 23, 2015 at 4:13pm
Gavin wrote:

Battery people are complex. Look inside us, that will explain us!

On June 23, 2015 at 4:47pm
bertie wrote:


I have been in the battery industry for 45 years and over they years heard the same regret repeated again and again. Nearly every person in the industry took the only job on offer and have regretted ever since getting into this miserable line of business.

This was a proper industry once. About 30 years ago the accountants got in and turned it into a monopoly game.

On June 23, 2015 at 5:01pm
Gavin wrote:

I’ve only been in the industry for 5. Machine Operator for 4.5 years first after coming out of uni and worked my way into a technical role been doing that for the last 7 months. At the moment though I’d say I’m far from miserable. It pays decent enough money to keep me my girlfriend and my 9 month old daughter happy,  in a house with food and a bit of money to do stuff with. And it gives me something new to do everyday. As I work on process and product development.

On June 26, 2015 at 3:55am
Alice wrote:

Gavin, Food for thought ......    The person running your company, (qualifications such as CA & MBA), probably earns a thousand times what you earn, yet you probably know more about batteries than he does.

On June 26, 2015 at 5:11am
Gavin wrote:

Alice, I think you’re pointing out something that everyone knows.
Its the same thing with every company in the world. The guy at the top knows how to run a business, doesn’t even need to know anything about the business. Let the people below him/her worry about that, and let the people below them worry about that etc. All the way down to the operators. No operators = No products. Yet operators are the worst paid.
That’s Life.

On June 26, 2015 at 5:59am
Alice wrote:

Gavin, It happens only in smoke-stack industries such as battery manufacturing. Industries that have been around a long time, working with technologies and concepts that have gone beyond their sell-by date. It does not happen in cutting-edge, “silicon valley” type industries. People who refuse to share profits don’t grow.

On July 30, 2015 at 11:58am
Gary wrote:

Pulse charge does work as a desulfation process it’s called a regenation you lot have no idea

On July 30, 2015 at 3:54pm
John Fetter wrote:

Gary - All you need to do to convince people is to back up your statement with scientific evidence.

On July 30, 2015 at 11:47pm
Gary wrote:

I will after work. I work with battery all day building them and returning the and as the uk no1 battery company we use pulse technology a lot.

On August 3, 2015 at 2:24am
John Fetter wrote:

Gary - Perhaps the information you’re looking for has turned out to be difficult to find.

On August 3, 2015 at 4:41am
Gary wrote:

No ant had time to write it.

On August 3, 2015 at 4:54am
Gary wrote:

Pulse technology works best when the battery is at top of charge 2.75 per cell once it’s at this stage the pulse can start working at its best by throwing amps in eg 400amps per pulse per second.wich are then able to break up the crystals on the plate. A lot are people thing that pulse technology will put active material back on the plates once it’s hot the mud puddle this is wrong Al it does is desulfates the battery nothing more. I have had good results from this we use a machine called a macbat witch is really good pulse technology and have got batterys lasting 1h over a c5 rate back up to 5 hours.

On August 3, 2015 at 6:47am
John Fetter wrote:

Gary - I beg your pardon but 2.75 volts per cell is way above top of charge. If you put 400 amp pulses on top of that, you will blow the active material out of the plates, corrode the positive grids, damage the separators and overheat the battery and after it has all settled down the mud traps will be full. If you have not quite killed the battery, the underlying residual active material might give the battery a fraction of the original ampere hours.

On August 3, 2015 at 6:56am
Gary wrote:

Jon- been using this method for 4 years not one battery ever come back.  Dnt get me wrong if the battery is turd in the first place it won’t work. And this is for deep discharge batterys not little blocs. Sorry but you are wrong. As you will now when the battery is coming to its final stage of Charging volts hit up to 2.6 to 2.75 this is when is at it most effective

On August 3, 2015 at 7:42am
John Fetter wrote:

Gary - I repeat, please provide scientific evidence. Tell us where there is a graph showing an actual recording of before ampere-hours, after ampere-hours. Your opinion is no more than your opinion.

On August 3, 2015 at 11:01am
Gary wrote:

John - we have a process in place which is volts and percific Gravitys when the battery arrives then we do a full capacity test of the battery taking each cell down to 1.7 per cell under load. Then we place the battery on a pulse technology machine for up to 72hours once a gravitas are at 1280 process done then more readings and a final capacity test over a c5 rate hence befor and after test with good results up to you what you think but it work. Bye .... smile

On August 3, 2015 at 12:51pm
Peter wrote:

Great conversation, sounds like Gary is using a process that works for the company he works for. Thanks for the detailed explanation.
John sounds like you have the resources to disprove this by setting up a test process as explained and graphing it then presenting the results. It does not sound like Gary has the resources, nor do they need to prove or disprove it, as they think it works for them. So do there customers and as he says no returns in the 4 years he has been doing it. That said if the batteries were never toast to begin with maybe nothing has been gained accept returning a good battery to service. My experience is people think things are broken but actually are not just not properly used or in the case of batteries not properly charged. Anyway I just bought a new “Nautilus Charger” from Canadian tire it has pulse desulfation technology built in as do my Soneil charges in my EV so somebody thinks it works. So far my used 6 volt deeep cycle cells which I am now properly charging are standing up to the demands of my EV. Sustaining 100-200 amp draw while driving and peaking at 400amps if I hit the pedal going into a hill. Connecting the Solar panels in the next few days I hope. Anyway I’ll be continue to listen.

On August 3, 2015 at 5:17pm
John Fetter wrote:

Gary - You have finally told us what your device does. It charges batteries. Then adds a strong equalizing charge.
There are serious users of motive power batteries, such as your large supermarkets, who run many hundreds of batteries per distribution warehouse, where motive power batteries don’t sulfate. They are used. They wear out through corrosion of their positive grids.
Smaller users often neglect their batteries and they end up undercharged. Your device is simply charging these batteries. I have tested these big pulse units. I have taken measurements. They do not desulfate the batteries. They charge the batteries.
Peter - You are dead wrong to suggest that Gary does not need to provide proof. I visited the Birmingham materials handling trade show some years back. There was a company exhibiting the Macbat. I asked the salesman how it works. He told me he had no idea but his customers had told him it works. Caveat emptor - he who buys is a willing fool.
I have done some research into the manufacturer’s background and have read their patents. I stand by my observation that their unit charges the battery and carries out an equalizing charge, period.

On August 4, 2015 at 12:50am
Gary wrote:

No it don’t charge then a strong equalise. It’s instantly pulsing from start to finish if you have seen these then you would no this. Amount off amps put out depends on battery size. A desulfated battery is not a broken battery just not been used as it should be. There is no machine out there that will turn dead material back in to active material.  Although Mac bat claim it does but I dnt think so. But every lead acid battery surfaces if not used properly hence the pulse technology cames in. Not that it is needed as a good cycle will sort this out. But Al I’m saying is from my experience pulse technology does work as for stranded charging pulse technology it’s not the best but same do see results..

On August 4, 2015 at 1:03am
Gary wrote:

Peter.  Thanks for your comment

If ur having problems with charger try looking at the fronuis market great charger bit pricey but well worth the money will charge any thing from nic-ads sonnisyne gel blocs fx the lot. Also have profile for Charing over discharge batterys eg if you have 48v but is reading 15v this will pick it up with a simple change of a profile also has pulse technology on it also has a 6 hour charge time great charger

On August 4, 2015 at 1:46am
John Fetter wrote:

Gary - You said on July 30 “you lot have no idea”.
Then you explained that you take the battery down to 1.7 volts per cell under load, after which you put it on the machine for 72 hours until the cells have a specific gravity of 1.280. I can assure you that what your machine is doing, in plain English, is called charging. The energy supplied by your machine can be dc or pulse, the process is nevertheless called charging.
If you continue the process above 2.6 volts per cell, the diplomatic way to describe the process is “equalization charging”. If your machine is pushing a high amperage and/or is applying 400 amp pulses, above 2.6 volts per cell, the technical way to describe the process is “overcharging”.
You have failed to produce evidence that pulsing does anything special.

On August 4, 2015 at 2:12am
Gary wrote:

Okay I no it works times and technology have changed john since you no it al though guess it dnt matter

On August 4, 2015 at 2:59am
Gavin wrote:

I completely agree with John here. in his most recent post, everything he said is correct.

I guess the best way to judge if the pulse desulfation works is to cycle 2 batteries for ‘X’ cycles where you discharge it to say 80% DoD,- but then do not fully recharge. Do this until you can be fairly sure that there is some IRREVERSIBLE ‘hard’ sulfation - that no amount of normal charging would remove.

Tear one battery down and analyse the sulphate levels and put one battery on the pulser and tear that one apart to see if there is any difference.

On August 9, 2015 at 6:27am
Marino Guerieri wrote:

I’ve been fooling around with desulfation, or at least what I believe to be desulfation. Here is what I’ve done:

I put a not so well performing battery on AC/DC adapter which I found somewhere lying around (because my smart charger refuses to overcharge) and was overcharging it for 2-3 weeks @ 15V, 0.5-1 Amp. Battery life improved from 20 minutes to 1:40 minutes in my 100w bulb hooked on inverter test. The battery was boiling with quite some intensity in the process.

Obviously something has happened.

But the thing is:
Is plain overcharging any better than discharge/charge cycles? Would it produce the same results? I could have just put a battery through, say 10 cycles and see what happens.. ?

I’m not a believer in all that desulfation products, but clearly there is some benefit to be achieved my mere charging or overcharging. And it’s not snake oil! smile But the extent to which it works is something I can’t predict.

On August 10, 2015 at 6:15am
Alice wrote:


You seem surprised by what happens when you charge a battery. As it reaches full state of charge it begins to gas. That is pretty normal. Your battery wasn’t boiling, it was gassing. If you allow it enough time on gassing, it will reach full state of charge.

On August 18, 2015 at 7:58am
Robert Seattle wrote:

John Fetter -
You have made several mentions of cycling charger power, turning your charger off and on, repeatedly, during desulfating experiments. Is your theory for this, to capitalize on the voltage spike upon charger start up, or something more devious? Believe it was low amp, 30 minutes on, 30 minutes off, cycle.
What results, if any, did you notice by preforming this action? - Thanks

On August 18, 2015 at 9:49am
John Fetter wrote:

Robert - I ran experiments on cells in glass jars. The negatives had been deliberately left standing for 5 years in acid, to encourage them to become 100% sulfated. I could see what was going on in the negatives by the changes in color and in surface texture. Success came after 3 weeks of charging up to 2.6V per cell for one hour, followed by one hour standing, followed by one hour charging up to 2,6V, alternating repeatedly. I ran a discharge test at one week, two weeks and three weeks. I had dosed the cells with cadmium. Simply connected a cadmium metal stick to the positives for about half an hour, in the beginning, which put enough cadmium into solution. The cadmium plated out on the negatives during charging, and went back into solution during standing. The cadmium reintroduced electrical conductivity into the negative active mass, outwards from the grids. I measured 100% restoration of capacity at the end of week three. I limited the charging current during the first 2 days, after that allowed the charging current to self adjust. It did not go up very high.
Sulfation occurs deep inside the active mass. Sulfation disconnects the active mass electrically from the grids. The cadmium forms dendrites that act as seed connectors. The conductivity spreads out away from the grids like tiny waves.
The overwhelming majority belief is that sulfation occurs on the surface. Good luck to them. I treated the problem as if it occurs deep down. It worked.

On August 18, 2015 at 3:26pm
Robert Seattle wrote:

John Fetter-
You also referenced on and off cycling (BU-804b) on, March 6, 2013 at 12:48am. Any significance to my inquiry in re voltage spike to assist your process involved? - Am I looking outside the box, when there’s nothing to see? - Thanks

On August 18, 2015 at 4:10pm
John Fetter wrote:

Robert - No connection whatsoever.

On August 20, 2015 at 12:51pm
marcel gerrits wrote:

Hi -  I am importer for a leading brand of motorcycle battery here in south america.

As our economy has turned acrid (pun intended) I get more and more returns.  As the owner, I do my best to defend myself from unjustified returns but am singularly uneducated in this field.  I do, however, have much experience examining hundreds of batteries.

My procedure upon receiving a return:

1.  If it is an unsealed battery, I will check visually if the cells show any kind of white discoloring visible through the translucent plastic casing.  Usually there is.  Then I will take the cap off the cell in question, pour the liquid in a glass and test the density with a gravity tester.  If the liquid is not water (happens often!) it usually is out of the recommended range of 1.32.

2.  I will dump out the liquid of cells that are out of range and replace them with fresh acid.  Then I charge with Sears charger that my tester shows to deliver 13.92 volts - sometimes for a whole day.  Let it cool for a night and repeat the next day.

Usually, this will work.  Once in a while, though, battery wont come back.  Question: Any advise?

The batteries I import are great and it winds me up to no end that my customers (dealerships, re-sellers) lie like politicians on the campaign trail.  I have activated literally hundreds of batteries and NEVER have had a dud.  Of course, I test the acid before loading and then charge for an hour.

Can you add anything to my precarious position to as to make me more capable to defend myself against my carnivorous clients?


On August 20, 2015 at 5:11pm
John Fetter wrote:

Marcel - You say that the batteries you import are great. You may be overlooking something. The batteries were transported from the factory to you - and I think you might be surprised to learn that the batteries are likely to have been exposed to excessively high temperatures and might have spent a very long time in storage and transport.
Batteries in containers that are out in the sun for ages are likely to get sulfated. Batteries that sit in a shipper’s warehouse for ages are likely to get sulfated.
Do you charge the batteries upon receipt? Do you make sure you are selling a fully charged battery?

On August 20, 2015 at 5:35pm
marcel gerrits wrote:

Thanks for interest John Fetter-  the batteries I have are dry motorcycle batteries.

They are sealed and, from what little I know, they do not expire because they are vacume sealed.  I do have some batteries that come with acid and charge direct from the factory and those I am careful never to allow to drop below 12.3vlts.

The dry batteries you add acid -some come equipped with included acid pack- while others requiere the customers to buy the acid.

Virtually all problems- overall less than 1% of sales- appear with the batteries that require the client to buy the acid.  Often clientes will buy a bottle of acid and then when they are a little shor, just add a tad of water.  Other times, they will recycle the old acid.  Another case still, is that the motorcycle has a defective current-delivery system.

I almost always recoup batteries with my procedure. 

Nonetheless, I would love to hear anything that may help me minimize problems.

I have a couple of batteries that have visible white blotches on a couple of cells due to clients loading them with water.  I am considering just rinsing them with soap- just for kicks!  Once again, any tips are welcome and will be tried enthusiastically!

On August 21, 2015 at 12:18am
John Fetter wrote:

marcel - There will always be a percentage of battery users who treat batteries badly.
I would like to touch on a few points that might be of help.
NEVER allow the customer to become part of the battery reconstitution process. Period.
Batteries delivered dry are either unformed; or formed and thereafter have had the acid removed. Unformed batteries need to be formation charged, given anywhere up to 350% of their ampere-hour rating, before they are fit for use. Formed and drained batteries need to be charged before they are fit for use, regardless of the way in which they were sealed.
If the acid is added and the battery is pressed into service without charging, it will have fully charged positive plates and partially discharged negative plates. The negatives will, in all likelihood, never become sufficiently charged after that. I suspect you might have been told by the manufacturer there is no need to charge.
I will explain. A wet lead-acid battery negative plate will become fully discharged within minutes when fully exposed to air. The fine lead crystals in the plate will react very quickly with the oxygen of the air, it will get hot and it will be oxidized. The vacuum sealing can only prevent total discharge, not partial discharge. This is not theory. I have tried it.
The battery will, no doubt, be able to start the engine but its capacity will be much reduced.

On September 9, 2015 at 6:33am
Owen wrote:

The Navy has reconditioned batteries for decades - my dad was in the Navy in the 1050’s and they would use a high voltage ‘spark’ and had done so for long before he was there - so the basic technique has been used almost as long as lead acid batteries have been around

On September 9, 2015 at 7:20am
Dr Jack wrote:


You might like to explain how the spark was used. I ask because sparks have a rather unfortunate side effect. They are inclined to make batteries explode. Submariners keep their batteries charged as much as possible in case they run into unfriendlies and need to get away as fast as possible under water. It is highly unlikely for such batteries in service to become sulfated. The batteries ultimately fail because the positive grids corrode, the positive plates shed active material, and the batteries lose ampere-hour capacity.

On October 31, 2015 at 9:39am
burner wrote:

Crap.  If you miss the image entry code, your message goes away.

1. Should I use a deep cycle marine battery, or a stationary type, for my pellet stove backup power source?

John said a stationary battery is meant to exist on trickle and only be cycled “a few” times.  How few is a few?  Can they be deep draws?

2. Should I habitually put my cars on my 12A charger for X hours every Y weeks?  One has a 20 minute commute per day, the other a 5 mile round trip once a week or so.

On January 12, 2016 at 2:57pm
Cor Meester wrote:

First of all, sorry for my poor English and low knowledge about batteries. I don’t think it’s as easy as it looks but if I take two normal start batteries of let’s say,  12 volt with 6 cells and 100 amph. Than I take out all the sets of plates. Than I take out tree of the cell walls so I than have 2 batteries with tree compartments. Than I connect every pair of two lead plates together. So I get 6 sets of plates with double thick plates. Is it possible to create with this materials two 6 volt batteries with high amph wich I am able to use a little bit more as deep cycle batteries? This was jus a (mabey stupid) out of the box thought.

On January 14, 2016 at 1:54pm
Steel Cycler wrote:

John Fetter- You have been working batteries a lot longer than I. Please advise on the best methods to extend the life of the lead-calcium alloy batteries that we currently use, especially how to prevent the dreaded open circuit effect from an insulating layer that occurs. Thanks, Steel Cycler

On January 16, 2016 at 11:59pm
John Fetter wrote:

Steel Cycler - Vide supra.

On January 17, 2016 at 5:48am
Steel Cycler wrote:

Ok I understand you want me to look above, but with all the other topics and the length of this column it’s almost like finding a needle in haystack. Mainly what I found is, do not operate battery in low SoC for extended periods, and when charging go for a fully saturated charge.  I’ve been testing various types of battery maintainers and they vary greatly in their approach.
  Brand A is rated at 1.5amp and will hold that amperage until 14.6v is reached, then it will reduce amps as needed to maintain 14.6 until only 0.25 amps are required, shuts off and repeats in 12 hrs.
  Brand B will go to 14.4v and transition into float and hold 13.4v. indefinitely.
Other models vary. The question then. What is the optimum charge method that will prevent life-shortening maladies and keep a battery’s capacity up? Will float current actually shorten life as some claim? (Mainly use starter batteries)

On January 17, 2016 at 6:11am
John Fetter wrote:

Steel Cycler - Use Brand B. Lead-acid can be floated at 13.4V indefinitely. Alternatively, for flooded float and boost 12V battery to 15V for one hour per week. I refuse to use sealed lead-acid. Most electronic charger designers have scant knowledge of how lead-acid works. I have finally found one electronics company that knows exactly how lead-acid works, called Victron Energy. They make inverters, chargers, solar controllers.

On January 17, 2016 at 1:37pm
Robert Seattle wrote:

Steel Cycler - <Some claim a float current (charging) shortens battery life>. Now there’s a new twist I haven’t heard before. Be careful, the more you learn about batteries, the more addicted you will become, for more knowledge.
John Fetter wrote <15V for one hour per week>. For those that caught that; you may be opening a can of worms many discard because their owners manual says: ‘Only once a year’.

On January 17, 2016 at 2:18pm
shawn wrote:

To all, our newest efforts are in the area of mid-size emergency DC back up power supplies (i.e. large lead acid battery packs) and to providing our customers (and future customers) with a complete and holistic battery life cycle management plan that covers both extended qualified/design life and long and arduous duty cycles. We are experts and focused on the newest revisions of IEEE 485, 535 and 450 for VLAs, and will likely be moving into VRLA area.  I am about to start a string devoted to this area and wanted to gauge interest on this string. We are mostly helping our utility customers in their efforts to comply with recent NERC/FERC type directives.  Let me know if you have ideas and subject areas you would like to start out with, email shawnuees@gmail.com

On January 17, 2016 at 11:18pm
John Fetter wrote:

Robert - You’re about half way into the discussion. Would you like to provide the details behind the twist, the addiction, the can of worms and the owners manual?

On January 18, 2016 at 1:43pm
Robert Seattle wrote:

John Fetter -
The twist – <see: Steel Cycler: 17Jan2016 @05:48> “Will float current actually shorten life as some claim?” [Reply] As you have pointed out many times, charging will affect, electrolyte, gravity, diffusion, plate cohesion and corrosion. The float process, is necessary to maintain battery health and longevity, despite minor negative concerns.

Addiction – [Reply] Self explanatory.

Can of worms – [Reply] see above Battery Equalizing: Sep. 25, 2013 @ 5:07pm by John Fetter and, Sep. 29, 2013 @ 2:55pm by John Fetter, for details.

Owners Manual – [Reply] see: CTEK 4.3 User Manual, pg 8 EN: RECON “Recond your battery once per year and after deep discharge to maximize lifetime and capacity”.

On January 18, 2016 at 4:15pm
John Fetter wrote:

Robert - The CTEK 4.3 is a product that requires the purchaser to believe that batteries need desulfation treatment.

On January 23, 2016 at 9:45am
Muhammad Shakeel Ahmad wrote:

Its Shakeel from Pakistan

Last month I tried to desulfate my 12V battery. It was dead and must be replaced.
I first rinse it with water and then treat it with saturated magnesium sulfate hot water solution.
Its more than a month and battery is working fine. Scientifically i guess hard cryatals of lead sulfate have been separated from lead plates paving the way to clear the flow of electrons.

I am not familier with pulsing devices but I guess pulsing would separate lead sulfate crystals.

On January 23, 2016 at 11:04am
John Fetter wrote:

Shakeel - The way you have explained what you have done gives the impression that you replaced the battery acid with magnesium sulfate and after that the battery began to deliver an electric output, without anything else being done.

On January 23, 2016 at 11:17am
Muhammad Shakeel Ahmad wrote:

@ john fetter
Wht is did was as follows:

1. Drain the water from ur battery and wash it for three to four times by pouring water and shaking it.
2. get around 1kg Apsom salt ( MgSO4 (magnesium sulphate) ) and make a saturated solution with water at approximately 70 degree C..
3. fill the empty battery with this heated solution and shake it well then drain it.
4. do it for 2 to 3 times. (remember to shake the battery for 2 to 3 minutes and retain the solution for 4 minutes after shaking, then drain it).
5. finally wash the battery again with tape water.
6. fill the battery with recommended diluted acid and connect it again with ur UPS. Charge it for 8 hours without external load.
7. your battery is new now. (Save money)

(according to literature battery retrieved from this method should properly function for 3 to 5 months. after that you must have to buy new one. (well i didnt try it twice with one battery. u should grin )

This salt is available at Kasur scientific store located near noor mahal cinema at the cost of 90 PKR/packing.

On January 23, 2016 at 6:12pm
John Fetter wrote:

Shakeel - You apparently began with a discharged battery, which would have at the time had an acid SG of less than 1.100, replaced the weak acid with a solution of magnesium sulfate. Left the magnesium sulfate in the battery briefly. Then you drained the battery and put in an acid that was probably stronger than the acid you originally took out. Then you charged the battery, which would have caused the plates to give off plenty of sulfuric acid and brought the electrolyte up to an extra high SG. You would most likely have obtained the same results if you had omitted steps 1 to 5 and the first part of 6, but simply added some extra acid and charged the battery. The step involving the magnesium sulfate is a red herring. It contributed nothing.

On January 23, 2016 at 11:57pm
Muhammad Shakeel Ahmad wrote:

It might be possible that my battery just needed fresh acid. I didnt notice this fact.
before I treat the battery with salt I add acid to fill the battery but ur argument may possibly be true bcz I disnt fully replace the weak acid with fresh acid.

On January 24, 2016 at 12:07am
Muhammad Shakeel Ahmad wrote:

John fetter

I want to establish a factory to recycle lead acid battery. I want to first recover the battery and fully charge it so that I may get pure lead plate at the negative and lead oxide plate at the positive and sulfuric acid as electrolyte.
The open the battery and reclaim pure lead plate for melting and alloy making . Lead oxide to crush and sell as it is and sulfuric acid

I want to ask if you could help me out if I am right.


On January 24, 2016 at 12:25am
John Fetter wrote:

Shakeel - I am not the right person to ask for advice and who can provide guidance about battery recycling. Sorry.

On February 6, 2016 at 10:19am
Eddy wrote:

Have you heard of Battery Extra EX02 desulfator? If yes, how would you rate them?
Secondly can’t it be used to rejuvenate fairly used 12v, 265AH GEL type batteries?

On February 7, 2016 at 3:45am
bertie wrote:

An advertising start to your new New Year job as a battery desulfator salesman Eddy? See BU 805, Jan 11, 2016.

On February 7, 2016 at 4:45am
brian wrote:

Eddie found this video on the Battery Extra at youtube might help you http://youtu.be/LpwBG1Nnfug

On February 7, 2016 at 5:07am
bertie wrote:

Another salesman

On February 7, 2016 at 5:28am
Eddy wrote:

@ berries! ! I would love to have your positive contribution please!! And no I am looking or starting a new sales job!! I am however looking to purchase a battery regenerator!

On February 7, 2016 at 6:27am
bertie wrote:

Hamlet then turns to his mother and asks her, “Madam, how like you this play?”, to which she replies “The lady doth protest too much, methinks.”

On February 9, 2016 at 8:42pm
Bob B wrote:

I cannot say that desulfators work, but I have used a batteryminder /pulse desulfator on each of my motorhomes 8 D batteries which I just replaced this past summer and they had been in service for over 11 years usung the charger/ desulfators.
  The previous set of batteries only lasted about 5 years before I changed them from battery tender chargers to the batteryminder pulse charge/ desulfators, & new batteries;  also after changing to the battery minder chargers I have not needed to regularly keep adding distilled battery water as they did not appear to boil over like they did with the battery tender chargers

On February 10, 2016 at 10:37am
Robert Seattle wrote:

Bob B - Question - Were your 5 yr old replacement batteries the *Exact Same* as the ones you got 11 years use out of? Exact same use/storage conditions and same maintenance program, except for the charger? Reason I ask is, I too have used the Battery Minder and Tender chargers and didn’t find the results much different than a simple $15. XM-1 Schmacher 1.5A charger, plus, they ran hotter than I was comfortable with.

On February 21, 2016 at 5:18am
raj wrote:

is sulfation, is also caused by battery kept for idle for long time and also if you added normal water instead of distilled water.. www.powerwale.com

On February 21, 2016 at 7:17am
bertie wrote:

Bob B
My car battery is 11 years old. If the car stands for more than half a week, the battery is connected to a PLAIN float charger and left on float charge until the car is used again.
Charger manufacturers recognize that their products are sold over the counter. Customers are easily persuaded to ignore the plain charger and to buy the more expensive charger with desulfation bells and whistles, simply because that is how retail works. So they fit desulfation bells and whistles. Does not mean the desulfation bells and whistles actually need to add anything of technical value.

And another thing. Links signal really bad vibes.

On March 10, 2016 at 3:50am
Frank Thompson wrote:

Andrew Neil provided a link to one of the most dangerous websites on earth.

On March 10, 2016 at 4:23am
brian wrote:

link is for very very long advertising video for an e-book, I guess a kind of how to book. God knows what downloads with the video. Frank could be right might be dangerous.

On March 17, 2016 at 5:19pm
Denis Castonguay wrote:

I want to learn more about batteries . which book can I buy to learn more.
thank you

On May 9, 2016 at 5:03am
Steve D wrote:


I’m dealing with an AGM battery bank, 900 Ah, 24 volts, made up of 12 volt cells, roughly 2 years old with less than 400 cycles.  The owner has reported diminished capacity recently. I had him test resting voltage of each 12 volt battery and after 6 hrs each was slightly above 13 volts, which seemed high even for an AGM.  Would this imply sulfation, or that the batteries have simply reached the end of their life?  The bank is aboard a boat that has been on charge most of the winter while the owner lives aboard, so batteries are in float much of the time, except when a load is placed on the bank, at which point chargers go into bulk for a period of time and then return to float.

On May 9, 2016 at 5:27am
Dan wrote:


I would doubt the figures your customer has given you.

On May 9, 2016 at 5:37am
Steve D wrote:

Why do you say that?  I confirmed each step, turning off charge sources for 6 hrs (all AC power disabled, no genset running, no shore power), and then measuring voltage after isolating batteries from each other is straightforward, so I’m confident he did it right.

On May 11, 2016 at 12:39am
Art Schultz wrote:

If the batteries were sulfated, would they ever reach 13v at rest? Dan may have been on to something in doubting the figures given by the customer. The tested voltage isn’t the figure to doubt though. That is pretty easy to get right.

I recently installed an amp-hour meter on my boat. I found that there is a dramatic gap between my assumptions about power consumption and what actually occurs in the system. Without knowing anything else about your customer’s issues, I’d say that if all of the component batteries hold relatively identical resting voltages, then you should find something else to worry about.

On May 11, 2016 at 12:59am
John Fetter wrote:

Steve - I purchased an inexpensive digital multi meter years ago. It began reading high after a couple of years and I changed the battery. After that it read normal again. Apparently a dying battery can make the multi meter become optimistic.
Sulfation is something that happens more in peoples’ imagination than in lead-acid batteries. Batteries that are deep cycled and/or kept on a relatively high rate of charge wear out due to positive plate corrosion and active material shedding.
AGM is likely to be on the way out at 400 cycles. There is a penalty for maintenance-free - reduced service life.

On May 11, 2016 at 3:42am
Steve D wrote:

The battery banks’s capacity is genuinely diminished, hard to ignore or worry about something else.  The bank carried the vessel’s loads for 12 hrs, now struggling to go for 6.  At $6000/bank, this isn’t something that can be ignored.

The last bank lasted for 1000+ cycles, similar use with the exception of more time at float, float voltage is correct, temp compensated.

Interesting about the multi-meter.  I’ll have him check it against the vessel’s volt meter now.

I’ve had many cases of AGM batteries that were allowed to go completely dead, and afterward recharged quickly but had seriously diminished capacity.  An equalization brought most of them back to life.  The part that’s confusing me in this case is these batteres weren’t allowed ot go dead, and the high resting voltage.

On May 12, 2016 at 11:07am
Linus wrote:

Hi everybody,

Have read the comments top down for all day.

Let’s make a resume. John says, that desulphators, which apply electric pulses - doesn’t reverse sulfation. On the other hand - if i understood correctly - it removes the calcium oxide from the grids.

So in practice then - desulphator helps, just the theory behind it is wrong. Am I right?

On May 12, 2016 at 4:07pm
John Fetter wrote:

Linus - Calcium oxide?

On May 13, 2016 at 3:32am
Linus wrote:

Sorry, my bad. You said in the beginning:

“The original alloy was lead-antimony. The new alloy is lead-calcium. An ultra thin oxide layer forms between the positive grid and the positive active material. Eventually the battery does not accept charge, does not deliver amps. Battery manufacturers have a few names for this condition: (1) “open circuit” and (2) “antimony-free effect”. Pulsing breaks down this oxide layer.”

So, that means pulsing is good for battery, just the theory is wrong - it does not do anything to sulphites.  So is it worth pulsing or not?

On May 13, 2016 at 4:51am
John Fetter wrote:

Linus - I believe it sometimes works, sometimes not. After-the-problem-has-developed battery cures are equivalent to watering dried out plants. Lead-calcium is a bad technology but a good commercial concept in today’s world of throw-away products.

On May 16, 2016 at 3:27am
ivo wrote:

Please stop with the “car battery does’t charge at idle engine speed” thing. This is complete nonsense, and if true means you have a problem with your car that should be fixed. Multimeter should read about 14-14,3v on idle even with lights, AC and such running at the same time.

On May 16, 2016 at 3:45am
Linus wrote:

Ivo - it’s only that high when alternator’s brushes are new. After some initial wear you would be happy if it reach 14V at all at idle with all accessories on. And it also depends of the built in charge controller - I noticed that ones manufactured in French tend to give higher voltages. Also it depends on how old is your battery. If it is old enough, even with new alternator you can notice a lights get dimmer when rpm’s are idle.

On May 16, 2016 at 4:37am
John Fetter wrote:

ivo - It might be worthwhile defining idle engine speed in rpm before making your assertion. It is adjustable. Some people set it low, others set it high. If you have everything off, the alternator will likely keep the voltage up at 14.3 but if you run everything as you suggest, I assure you it will not be able to keep the voltage at 14.3. Have you measured the current drawn by the lights with headlights on high beam? it is enough to kill a fully charged battery in 1.5 hours. I have tried it.

On June 4, 2016 at 9:22pm
Yohan Nugraha wrote:

I’m not a scientific guy, but I heard this product called PowerBatt from Slovakia that actually reverse sulfation of lead acid battery chemically, this is their website:


Is this possible? need a lot of input regarding this product since my company is planning to buy quite a lot from them for our forklifts

any information and comments is welcome
thank you guys

On June 6, 2016 at 3:32pm
John Fetter wrote:

Yohan - Forklift batteries that are in regular use do not become sulfated. That website - plenty of chatter, zero technical information. That should be a powerful clue.

On June 15, 2016 at 6:39am
Steel wrote:

Came across a 7 yr old Harley sealed 9AH battery, can be charged up nicely and has loads of reserve capacity, but after a full charge will settle to a stable 12.1 v open circuit voltage. Very little self discharge, just stays at 12.1 for days. Removed the sealed plugs and added a few cc of water in each cell. internally it appears much like a flooded cell but can be turned upside down without spilling. Anyway after adding water it stayed the same, 12.1v OC at 100% SoC, good cranking and AH. Still a good battery but why is the OC voltage that low?

On June 21, 2016 at 7:57pm
Joshua wrote:

The best way to desulfate a battery if a pulser or hard charging doesn’t work is water treatment. Not epson salts, that lowers the resistance of the battery, makes it hold more but ruins the plates. Dump all the acid out into a container (carefully obviously) or siphon it. An older battery may short out from all the junk at the bottom, it just depends. Siphoning is battery dependent but you wont short it out. Once its empty you just replace it with 100% distilled water and give it a long hard charge until the specific gravity hits 1.265. Basically it makes the electrolyte acid starved so the sulfate has lots of room to move and readily does so. Will eat some positive plate but so does all hard charging. Look up a book called the battery builders on amazon. LOADS of information.

On August 10, 2016 at 6:23pm

THE discussion on battery sulphation is most educative and informative to me. I am into solar PV electric system installation and maintenance,and cost of procuring and replacing batteries is major cost in such installations. Consequently ,information on how to prolong the useful life of batteries , by reducing /eliminating sulphation, is most welcome .THANKS.

On August 17, 2016 at 9:49am
Keith wrote:

Lead and lead oxide are the plate materials at full charge in a bath of sulfuric acid.  Both plates convert to lead sulfate with discharge and since this compound is at best a semi conductor, charging a dead flat battery is slow.  In addition to the electrolyte being mostly water.

The sulfate in amorphous state is easily converted because surface area per mass is great.

On August 18, 2016 at 4:53pm
John Fetter wrote:

There are over one billion automobile batteries in use around the world. Simple question. If sulfation really is a problem and sulfation cures actually work, why is it that over a period of 100 years no one has yet managed to grow sulfation cure technology into a large successful company?

On August 29, 2016 at 12:17pm
Battery master wrote:

Yes, there is, but you wouldn’t know about it. Simple answer.

On August 29, 2016 at 6:01pm
John Fetter wrote:

You would certainly be making a point if you would kindly provide us with the evidence.

On September 3, 2016 at 1:27am
Conundrum1947 wrote:

Hi, I inadvertently discovered a while back that most “dead” lead acid cells could be repaired by simply using a SMR unit (scanning molecular reorganizer) of my own design based on a modified 1.8T MRI scanner.  As all the materials are still there but in inactive forms simply moving molecules around recovers all the lost capacity and actually improves it more than even the original specifications (nanotech versus 1950’s tech) to the extent that a 60AH unit stored nearly 71AH as long as it was never discharged below 50% SOC. The problem is that this technology is not ready for manufacture as the unit only works in the laboratory under constant supervision by a human operator.

On September 14, 2016 at 9:25pm
Former Exide Employee wrote:

Sulfation as we know it is a problem of the past owing to advancement in battery technology and charging systems.

There is a young engineer in India who has come up with a solution for enhancing life cycles via tackling polarization effects. He has aptly said: If desulfators were a success, the battery manufacturers themselves would have manufactured them because lead-acid batteries have been around for decades.

However, given the weak patent laws of his country, he wishes to remain anonymous.

However, I would like to correct BU in letting them know that sulfation once present can be removed. However, as a chemistry graduate, let me tell you that charging systems can remove basic sulfate or PbSO4 or dibasic sulfate or 2PbO.PbSO4. Tribasic and tetrabasic sulfates are the types of sulfates that cannot be removed no matter how much equalization charge you may give to your sealed or flooded batteries as these two variants are related to grid corrosion in mA/100 Ah.

The engineer has named his product: Battery Life Enhancer as many of these desulfator manufacturers have but his concept is entirely different. He wishes to further improve upon it using Big Data.

On September 14, 2016 at 9:45pm
Former Exide Employee wrote:

I have interacted with PowerBatt people.

I once asked them: How does your chemical remove sulfation? What is the working principle? Like Donald Trump, they were cleverly trying not to answer the question asked.

As battery OEMs, we abstain from inserting any chemical that may benefit or not benefit the batteries. If these chemicals were to already significantly benefit the batteries, we would have already incorporated them in our manufacturing process.


On September 14, 2016 at 10:09pm
Former Exide Employee wrote:

John Fetter. I agree with you. However, antimony-free effect is taken care of at the chemical level by injecting low concentrations phosphoric acid that retards corrosion conversion from Pb to PbO. This is a patented process. We take care of it at the manufacturing level.

These desulfation devices do not account for separator resistance nor constant phase element that mimics an element that is party resistive and partly capacitive. Sometimes, what we have observed is that they enhance plate shedding which leads to plate shorting and within months you tend to observe a huge capacity loss. Every battery has a design cycle life. Claiming that a device removes “sulfation” would be equivalent to claiming that a battery shall last forever. And that is absurd.

On September 15, 2016 at 4:38pm
John Fetter wrote:

Former Exide Employee - A patent describing the addition of a low concentration of phosphoric acid to a lead acid battery was filed in Germany in 1926 and was issued in the USA as US Pat 1,748,485 on February 25, 1930. The antimony-free effect continues to plague motorists.

On September 15, 2016 at 5:33pm
John Fetter wrote:

” As battery OEMs, we abstain from inserting any chemical that may benefit or not benefit the batteries. If these chemicals were to already significantly benefit the batteries, we would have already incorporated them in our manufacturing process.”

Early lead-acid batteries were fitted with separators made of a variety of materials including thin wood veneer sheets and thin rubber sheets. When lead-acid battery manufacturers switched to what they believed to be superior polyethylene plastic alternatives, the performance of their batteries fell dramatically. It was only when this happened that the industry began to realize that lead-acid batteries need to include certain organic materials in order function properly. The industry eventually figured out what ingredient in the wood had been keeping their batteries working and managed to replicate it. It is a chemical substance called lignosulfonate. The industry never managed to figure out what made rubber work as well as it does and have never been able to replicate it.

Lead-acid battery manufacturers are, today, making a product they do not actually fully understand. They have a reasonably good understanding of the chemistry but are almost totally unaware of the electrophysics that goes on inside their batteries. They are not fully masters of the art yet persist in telling their customers not to try to improve the life expectancy of their batteries.

On September 16, 2016 at 2:17pm
Former Exide Employee wrote:

John Fetter: In science and tech, no one can fully be a master of any technology. Even quantum physics baffles scientists today. There is always scope for improvement. But I will explain ageing effects based on my knowledge so far.

As for separator science, that deserves a chapter of its own.

The active material of the positive electrode is prone to lose its mechanical strength when repeated discharge/charge cycles occur, because the alternating dissolution and precipitation processes, convert the agglomerate structure into an accumulation of fine crystals. So, the active material suffers degradation and part of it may fall off the plate as fine particles. This process is called “shedding”. Shedding of the positive active material is a characteristic feature of ageing conventional lead-acid batteries when they are charged and discharged frequently. It is likewise also described as “soft positives”. Shedding is only the outward appearance of a more general ageing process which means that the active material is prone to disintegration of its electronic conductivity and mechanical strength. This causes the so-called “premature capacity-
loss’‘. It becomes evident as a decreasing utilization factor with increasing

In a model that considers the active material as an aggregate of spheres (“Kugelhmfen”) it is explained by a gradual increase in the ohmic resistance, mainly in the connecting region of the individual particles of the active material. They connecting regions establish the electrical contact between the individual particles of the active material. They are decisive for the ohmic resistance because of the minimized cross-sectional areas in these bridging zones. The structure of the connecting regions between the particles of active material is largely influenced by the conditions when these regions are reestablished during the charging process. For this reason, it is understandable that the charging conditions are important for the stability of the active material and that in many cases, after a premature decay, full capacity can be regained with suitable charge/discharge procedures. For this reason, the premature capacity loss sometimes is called “reversible capacity decay”.

Another model assumes that gel zones are formed by hydrated lead dioxide (PbO(OH)2) and act as bridging elements between the crystalline particles. Electrons can move along the polymer chains of this gel and so cause electronic conductivity between the crystalline zones.

Quite often, simultaneously with the capacity decay, the formation of a barrier layer of lead sulfate (PbSO4) is observed between the grid and the active material.

In view of the explanation given above, this layer may be the final stage of the process. When the ohmic resistance of the active material is increased, the charge/discharge reaction is restricted to the area close to the grid surface. Then, deep discharge must happen to this part of the active material, causing a high concentration of sulfate.

On September 16, 2016 at 2:28pm
Former Exide Employee wrote:

In continuation:

Antimony (Sb) and tin (Sn) are usually not added to the active material, but both are alloying components of the grid. They are gradually released from the grid by corrosion, and permeate the active material by dissolution and diffusion. The “premature capacity loss” described above: a decay of the utilization factor, became especially evident when antimony-free alloys were introduced and such batteries were operated in charge/discharge cycle regimes. For this reason, this effect is likewise called the “antimony-free effect”, although it is also observed with grids containing antimony. I agree that the mechanism of this effect has not yet been explained in detail, but antimony has a strong influence on the stability of the active material that cannot be compensated by special pretreatment or design of the electrodes. When specimens of pure lead and a 5% antimony alloy were periodically oxidized and reduced, lead oxide layers were observed with different structures:

1. Coarse and insulating with antimony free electrode
2. Fine and low resistance with the antimony alloy.

The origin of such insulating layers may explain the high resistance also established within the active material when antimony is not present. The Kugelhaufen model mentioned in the preceding comment explains the beneficial influence of antimony by improved conductivity of the zones that connect the spheres. According to the gel model, antimony decreases the crystallinity of PbO, and so increases the conductivity by the gel zones, and especially influences the structure of the corrosion layer intermediate between the grid and active material.

Addition of tin to the positive-grid alloy also has a capacity-stabilizing effect, but this apparently concerns only the boundary between the grid and active material.
Phosphoric acid (H3PO4) is added in small amounts to the electrolyte. A beneficial effect on cycle stability has long been known for this acid, which has been used as an additive in conventional lead-acid batteries for many years to improve cycle stability, although the disadvantage of a slightly reduced capacity had to be accepted. Addition of phosphoric acid to the electrolyte improves long-term capacity and reduces the formation of sulfate layers around the grid. The addition of 20-35 g dm-3 phosphoric acid was protected by patent for VRLA batteries with gelled electrolyte.

Extensive experiments showed that, at low H3PO4 concentrations, Pb3 (PO4)2 acts as an intermediary in the corrosion of Pb to PbO2. Clearly, the phosphoric acid influences the formation of lead dioxide
(PbO2) on account of its strong adsorption and leads to a fine grain structure of the positive active material. However, in spite of the repeated use of phosphoric acid in lead-acid batteries, some questions on its interaction are still to be elucidated.

On September 16, 2016 at 6:09pm
Former Exide Employee wrote:

Dear Battery University, correction is needed for the following in inverted commas:

“Several companies offer anti-sulfation devices that apply pulses to the battery terminals to prevent and reverse sulfation. Such technologies will lower the sulfation on a healthy battery, but they cannot effectively reverse the condition once present. It’s a “one size fits all” approach and the method is unscientific.

Applying random pulses or blindly inducing an overcharge can harm the battery by promoting grid corrosion. There are no simple methods to measure sulfation, nor are commercial chargers available that apply a calculated overcharge to dissolve the crystals. As with medicine, the most effective remedy is to apply a corrective service for the time needed and not longer.”

1. Ant-sulphation devices have been found to reverse the condition once present. However, they are not recommended because they tend to create soft shorts that lead to premature capacity loss. In addition, the pulses contain ripple current that causes premature hating of the battery, which can be a dangerous buildup.

2. The method is not unscientific because of a one size fits all approach. We battery OEMs also use that approach to cater to applications. It is unscientific because it does not model battery behaviour correctly nor it can because electrode surface is always non-homogeneous. We work on statistical averages.

3. Boost charging does remove basic and dibasic sulfates. Boost charging does not remove tribasic and tetrabasic sulfates.

On September 17, 2016 at 2:26am
John Fetter wrote:

Much of the antimony and the tin alloyed with the positive grids comes out of the grids during routine end-of-charge overcharging, gradually during the working life of the battery, enters solution and is electroplated out onto the negative electrodes. Lead proceeds in the same way but much more slowly. How do I know? I constructed test cells with normal positives and special negatives that enabled me to detect and to measure the presence of these metals after they had been plated out on the negatives.

Antimony provides a degree of protection against corrosion and electrical disconnection between the positive grids and positive active material that no other material can provide. Calcium alloy positive grids are inferior to antimony alloy positive grids in terms of battery life expectancy. Antimony has a downside. It electroplates onto the negatives, promoting gassing. It has been known since the 1940s that this can be negated by the use of natural rubber battery separators. Natural rubber battery separators also help to reduce positive grid corrosion, water consumption and even self-discharge. (There is a reluctance to use natural rubber due to its high cost.)

The negative plate surfaces are covered with hydrogen nanobubbles, especially during overcharge. It has long been assumed that nanobubbles cannot exist for long and that they dissolve very quickly, in a matter of micro- or milli-seconds. They have recently been measured independently by several universities using physical measuring techniques and it was discovered that they are, in fact, stable. Resident hydrogen nanobubbles provide a permeable barrier across the surfaces of the negative electrodes. The barrier can be measured using simple electrical instruments and a reference electrode. The barrier is enhanced by the use of natural rubber battery separators.

The barrier impedes metal ions that are migrating from positive to negative and thereby helps to saturate the electrolyte. The barrier thereby indirectly protects the positive grids from corrosion. The barrier does not impede the underlying electrochemical charge-discharge battery reactions. It works in flooded batteries but almost not at all in maintenance-free batteries, which rely on oxygen gas recombining with emerging hydrogen at the surfaces of the negative electrodes, to help reduce water consumption. The arriving oxygen and subsequent conversion into water depletes the negative surfaces of hydrogen nanobubbles.

It ain’t all chemistry. No need to use models if we don’t understand how it works. Not exactly about sulfation nor premature capacity loss, but an example of a more twenty-first century approach towards a better understanding of how lead-acid works.

On September 19, 2016 at 4:25pm
Former Exide Employee wrote:

John - “No need to use models if we don’t understand how it works” - LOL

Oh! We have 21st century R&D capabilities, but we cannot simply disclose IP facts on a website forum.

We have collaborations with these universities. Only general information is disclosed for enthusiastic people.

On September 19, 2016 at 10:07pm
Former Exide Employee wrote:

John Fetter - We are EXIDE. We know more about what you are typing than you can fathom. But this is not to belittle you. We appreciate your enthusiasm.

But stop copying stuff from batteryvitamin.net

We already know about this.

On September 20, 2016 at 5:14pm
John Fetter wrote:

Former Exide Employee OR Current Exide Employee - Thank you for providing that insight. I have have dealings with battery manufacturing companies located in the USA, including Exide, East Penn Manufacturing, Trojan Battery, US Battery, battery component manufacturers like Microporous Products, and others; dealings with battery companies in the UK, France, Germany, Belgium, Luxembourg, Ukraine, Brazil, South Africa, Japan and Australia. Exide is one of many battery manufacturers that purchased products, needed for critical projects, from us. Apparently unable to produce themselves. The people at Exide obviously know much, much more than any individual - but never managed to figure how rubber works.

On September 24, 2016 at 9:54pm
Former Exide Employee wrote:

John Fetter - I guess you have a fetish for natural rubber.

Go figure it out then. Produce your findings in a recognized scientific journal. Then make money out of your IP.

On September 26, 2016 at 4:47pm
John Fetter wrote:

Former Exide Employee - The early battery manufacturing pioneers were genuine technical innovators and clever entrepreneurs. They did not ask for permission to innovate and did not give away their ideas at gatherings of scavengers. You’re telling others to give away their secrets but give yourself the right to hang on to your own.

You began by using a misleading pen name - then very clearly stated, “We are EXIDE”, and switched to the first person plural. This gives me permission to broaden the discussion. You paint a rosy picture of technical capabilities, yet the facts on the ground would appear to suggest otherwise. I would summarize by pointing out that Exide seemed to lose the plot during the last ten years of the twentieth century. The company announced that it would make the best batteries at the lowest price, but it seems it only managed to fulfill half the promise. The lowest price, the easy half.

Exide was founded in 1888 by William Warren Gibbs, then vice president of the United Gas Improvement Company, and was originally called The Electric Storage Battery Company. The company made practically all the US submarine batteries in WWII. The name was changed later to Exide, short for “excellent oxide”. Exide acquired General battery in 1987, CEAC including Sonnenschein in 1995/6 and GNB in 2000. Sonnenschein introduced Exide to phosphoric acid.

The acquisition binge and rash of complaints arising out of the best-batteries-at-the-lowest-price policy pushed the company into serious financial difficulties. The company went bankrupt in 2002. The company had been selling batteries known to be inferior, defined by the court as KNOWN TO BE DEFECTIVE, to a large well known retailer and Exide’s CEO was charged, convicted and sentenced to a fine of $1 million and 10 years in prison. The entire board was fired.

New management struggled to keep the company going until new money was injected and the company emerged from Chap 11. In 2010 Exide lost a second even bigger retailer due to battery quality issues which resulted in Exide falling back into Chap 11 in 2013. Exide was forced to close down a recycling plant due to arsenic pollution in the same year. Exide has worked hard since then to rehabilitate itself.

I have verified all the information. I would suggest that you have been delivering your oratory while standing on top of a rotten soap box.

On October 1, 2016 at 6:45am
Steel Steeds wrote:

I’ve been noticing a trend in the failure of Honda automotive batteries (not sure who produces them). Often one or sometimes 2 cells will be found to have shorted out so firmly that the battery can still be used as a 10 or 8 volt battery as the shorted cells are still able to carry cranking and charging currents needed, while the remaining cells remain in very good condition. Guess there is no way to rehab the bad cells, but maybe someone can diagnose what is going on and why. They are usually 3-4 years in service when it occurs.

On October 3, 2016 at 4:44am
Former Exide Employee wrote:

John Fetter - I used to work for Exide Industries India, which is not a subsidiary of EXIDE US.

I guess I managed to hit a nerve of a man who could get no recognition and hence, shows off about what he knows to people


On October 4, 2016 at 12:29am
John Fetter wrote:

“Former Exide Employee” - Congratulations. Absolutely yes. Success. You hid your personal identity, presented a false company identity and pulled it off. Indeed, I will go as far as to suggest that you have been successful in another area as well. You are helping outsiders to understand the Indian lead-acid battery industry better.

Your dismissive remarks, “we know more - we have 21st century capabilities - we cannot simply disclose”, are unlikely to confirm competency but are suggestive of an inadequacy felt in the industry. What honest purpose can be served by stealing the identity belonging to other people? You have nothing to worry about. The Indian government believes it is unfair for Indian businesses to pay royalties on foreign owned patents and for foreign businesses to have rights over their own IP in India.

The Indian courts ruled against Exide USA on September 5, 2012 concerning the use of the ‘Exide’ trademark in India despite Exide USA having originally coined the name Exide from ‘excellent oxide’, despite having filed the original trademark in 1901 and the stylized logo in 1904, despite indirectly being the parent company of Exide India via Chloride UK and owning the trademark in more than 130 countries. The appeal by Exide USA was dismissed on August 2, 2016. Your triumph can be gauged in that context.

On October 6, 2016 at 3:37pm
Former Exide Employee wrote:

Fake company - Are you foolish?

Ramblings of an old man. I pity you.

On October 6, 2016 at 4:40pm
Chris C. wrote:

This article is attracting a lot of controversy and understandably so as lead acid battery technology is quite complex, but could you please tone down the anger, it is so unnecessary!

On October 8, 2016 at 9:58am
John Fetter wrote:

Chris - Have you considered the possibility that the public may be interested to learn about the interesting goings-on in the battery industry? I have included some information based on what I have read in court records and company records. It seems like it is a somewhat “untidy” industry populated by emotional people.

On October 11, 2016 at 11:02pm
Chris C. wrote:

You are absolutely right, John, and I respect this being brought forward; but with what we’re exposed to these days with this unpresidential race you’ll probably understand my weariness wink

In any case, it’s all discourse in the pursuit of knowledge, after all, and granted, it’s going to be messy at times, but some people don’t understand this and take it personally and you simply can’t argue with that wink

On October 18, 2016 at 10:28am
Former Exide Employee wrote:

John - It it is going to get dirtier once Trump is elected.

On October 25, 2016 at 8:22am
Enda F wrote:

I have recently been reading the posts here and have found them very informative.  I have found some relevent to my situation.  My situation is as follows:
I have 8 by 12 V deep cycle flooded lead acid batteries (Crown) - 105 Ah each.  Connected 4 in series with these in parallel with four others to create a 48 V system.
Question 1:  I understand that this amounts to 210 Ah at 48 V dc or 42 Ah at 240 V ac (assuming there are no energy losses).  This should give me 42 Amps for 1 hour for a full discharge or 5 Amps for 1 hour for a 12.5% discharge (see question 4).  This is a very crude calculation but is it any ways close to what I should expect?

I am off grid.  I have a 60 A MPPT charge controller/inverter connected to 2700 Watts of Photovoltaic panels with a Diesel generator for backup.  The charger uses a 3 stage charging algorithm - bulk charging voltage up to 58.4 V (currently set to 58.4 V) and float charging voltage up to 58.4 V (currently set at 55 V).  The charger regularly reaches ‘full’ charge where the float voltage is reached and after a period of time the current to the batteries drops to 1 or 2 Amps.
Question 2:  Have the batteries now received a full saturated charge? Or is it just a 70% charge (as I read somewhere on this website)?
Question 3:  If the batteries periodically need a full saturated charge can it be done by adjusting bulk charging and/or float charging voltage?

When the batteries reach 42 V the controller turns off and no more power is taken from the batteries.  (I haven’t the generator set up yet to come on automatically).  Any way the batteries will only stay in this state for a few hours at most whenever this happens.
Question 4: Does this correspond to 12.5% discharge (i.e. 48 V - 42 V = 6 V.  6 V is 12.5% of 42 V)?  Again, here, I appreciate that this is very simplistic and assumes that discharge is linear.

I purchased all the various bits and pieces around this time last year and put it together with a good understanding of all parts except how the batteries charge/discharge and should be maintained.  For example, there were occasions when the batteries were not brought back up to ‘full’ charge before they started to discharge again.  As the weeks passed by I became afraid that their capacity was quickly dropping.  After ‘full charge’, say 6 in the evening,  the batteries need to provide power to 6/7 LED bulbs at any one time, 2 new efficient ‘fridges and 1 chest freezer (these latter appliances being only ‘intermittent loads’ which lead acid prefers).  At 8 in the morning the panels are providing power again. 
Question 5:  Considering the number of batteries that I have and their Ah rating should I expect that the batteries ‘take care of’ the above requirements between the times indicated or am I expecting too much of them?

I became concerned about a reduction in the capacity of the batteries as the weeks passed after getting them.  It also appeared that they became easier to reach ‘full’ charge.  However, as late spring and summer came the hours of daylight caused me to forget somewhat about the batteries.  The approach of winter has caused me to refocus.  Having read about equalization, I recently bought a Variable Power Supply (up to 60 V at 5A).  I disconnected one set of 4 batteries in series and left the charge controller connected to the other 4 so that I would have power for the PS.  I put a voltage of 60 V across the 4 batteries in series and left for 2 hours.  I repeated the process the following day with the other 4.  The current gradually rose to about 5.4A.  Having checked the SG recently, after ‘full charge’, I am typically getting a reading of about 1.225 where as I expect it to be 1.227. 

Question 6:  Does equalization ‘take care of’ sulfation as well as equalize the cells?
Question 7:  Should I equalize one battery at a time or can I do all 4 in one go.  If I need to go to higher voltages to equalize I would not be able to do 4 in one go anyway.
Question 8:  I suppose the important question is: what is issue with the batteries?  Is it an equalization problem or a sulfation problem?  And, using a PS, how do I solve these issues?

I would appreciate any help that I could get on these questions.

On October 26, 2016 at 2:03am
John Fetter wrote:

Enda - Most of what you are doing appears to be quite correct. I would never run batteries in parallel because batteries are not all the same and they will inevitably get out of step. Fortunately, it is possible to correct for this by disconnecting one group of 24 series connected cells, (4X 12 V) at a time and equalizing it up to 62.5 volts. A solar MPPT will probably typically take the batteries up to 58.4V, day after day, on bright days. That’s fine. Keeps the water consumption down. You absolutely must equalize every three-four weeks by holding the 24 cells at 62.6V until the charging current stabilizes. If you hold the charge too long, the batteries will get hot and current will start climbing again. Don’t let this carry on too long. Switch off. The batteries will be equalized. Equalizing regularly prevents sulfation, Prevents cells getting out of step.. Always equalize a full series string. Never try equlizing parallel connected batteries. Many solar installations undercharge lead-acid and lead-acid will not work for long when undercharged. There is no meaningful difference between 1.225 and 1.227.

On October 28, 2016 at 9:19am
enda wrote:

John - thanks for getting back to me.  Just a correction first on SG readings - I entered an incorrect value.  When I checked the batteries recently I got a value of 1.225 (after ‘full charge’) instead of an expected 1.277 (which is the figure given on the Trojan website).  On my hydrometer 1.225 is in the ‘red’ zone meaning the battery needs recharging even though the charge controller has moved onto float and the current has dropped to 1 or 2 Amps.  1.277 is in the ‘green’ zone meaning the battery is charged.  The SG of my batteries never manage to get into the ‘green’ zone.  Should this cause me concern?

You say to equalize (and I have only attempted it once even though the batteries are nearly a year in use) “until the charging current stabilizes”.  When I did I found the current rose to above 5 Amps but I terminated the charge after 2 hours.  There was no evidence of the batteries getting hot.
Should I have continued beyond 2 hours until the current stabilizes - no matter how long it takes?  I have a year of sulfation to undo - if this is possible. 
I noticed when checking the SG readings that the electrolyte had turned a greyish color.  Is this good or bad?
Considering the AmpHour ratings of the batteries and the loads attached - both given above - should I expect my batteries to power the loads for a 12/13 hour period?  Am I being too optimistic?

Thanks again for getting back to me.


On October 31, 2016 at 3:49pm
John Fetter wrote:

Enda - You are asking for but I am not sure whether you want to take advice.

On November 2, 2016 at 12:57am
Enda wrote:

John - I will very happily take whatever advice you can give.  Essentially, before I equalize the batteries again I want to be clear in my own mind that I am doing the right thing (correct Voltage and current), for the right length of time and not causing further problems.
I have the batteries a year.  Because I live off-grid they have already paid for themselves.  If I have to buy new batteries relatively soon I can put up with that.  Whatever mistakes that I am going to make with batteries l will make them with these ones.

On November 2, 2016 at 4:40am
Steve Parkinson wrote:

Interesting and useful article. Is it ok if I link to it from our website (https://advancedbatterysupplies.co.uk) We sell many Car batteries every day and I am sure a lot of the information here could benefit our customers.

On November 21, 2016 at 11:18am
Sam wrote:

i’m shopping to a good car battery charger, i hear ctek and optima 12000 are the best. the have the reconditioning modes, to reverse sulfucation.

have you had any experience with these chargers, which one to pick? for regular topoff and occasionally deeply discharged batteries.

i have a standard car battery.

On November 21, 2016 at 3:38pm
Patrick Gale Perry wrote:

Hi John!

I enjoy reading from your website often. Sometimes the volume of comments is overwhelming.

Each week I pickup about twenty 12 volt MK, Interstate (China) or Chineese deep cycle power wheelchair batteries. Many have set unused and discharged in powerchairs for years.

I attach standard Schumacher 30amp chargers (Walmart) for reconditioning them. These chargers go into a ‘desulate mode’ of fluctuating voltage and amperage for 10 hours if the voltage is below 6 volts. Small batteries like the U1 and 22NF are connected with multiple batteries because of too much amperage that may severely overheat the battery.

I have considered buying a Korean made Repowertek RPT C200. Are you familiar with them and are they worth thousands of dollars each?

If the finished voltage is above 12.5 volts but the internal resistance is above 8 milliohms, the cold cranking amps readings are usually below 50 (useless). Can I totally discharge these batteries with a 100 watt light bulb and ‘desufate’ them again to reduce the resistance and increase the capacity?

Is there a better way to recover these ‘bad’ gel and AGM recombinant batteries? I resell them to RV and solar power users.

Is there an inexpensive (under $100) digital amp hour tester? (I use a Harbor Freight CCA tester).

Thank you,
Patrick Gale Perry

On November 21, 2016 at 8:22pm
Paul wrote:

I have read this article a couple of times now, i find it very interesting and will use some of the info to help maintain my car battery from now on. I have recently purchased a Ctek 12/5 charger. I noticed you mention that Ctek requires the operator to believe that de sulfation is necessary. You mention that you have found a company that understands how to charge a battery, Victron Energy. I looked at 1 of the Victron Energy smart charger technical docs. My question is, Do you you believe the Ctek is sufficient to help maintain a battery. Both chargers have a Recond setting although voltage and current set points are not identical. Storage charge on the Victron Energy charger is slightly lower at 13.2 V which i take is a good thing.. Obviously i have the Ctek now but just wondering if you see the 2 chargers as vastly different.
The de sulfation step has never activated on the CTEK even when connected to an old battery that was sitting idle for 6 months. This battery will start the car but would die pretty quickly if radio or anything else was left on. It is about 6 years old.
Thanks for all the info in previous threads.

On November 22, 2016 at 11:10am
Sam wrote:


I’m in the process of charger selection. I understand Optima 12000 will do this step too (was thinking about CTEK also). You menioned Victron Energy, never heard of them.

On November 22, 2016 at 3:24pm
John Fetter wrote:

I am involved in industrial motive power and deep cycling and not at all in any commercial aspect of car batteries.

On November 23, 2016 at 9:59am
Sam wrote:

Got it.


Could you please share your insight on the differences among Ctek, Optima and this new one Victron Energy? Specifically on usability/ usefulness of de-sulfation of these chargers?

Thank you

On November 23, 2016 at 4:39pm
John Fetter wrote:

I am not a merchant. I don’t work with these commercial items.

On December 10, 2016 at 1:14pm
Enda wrote:

John - I equalized just last week at 62.5V for 2 hours - the specific gravity improved but seemed to stop at 1.225 approx (when the required value is 1.277).  Should I have continued for much longer?  The current initially dropped but started to increase after about 1 hour.  I noticed improved performance at first.  However, each day (or night) since, the capacity of the batteries has gradually dropped so that they are almost back to the point they were at before equalization.  Any further suggestions?
Another question.  As back up I use a generator.  When I bought the batteries first I charged them by means of a petrol generator via the charge controller.  The pv panels were installed a month later.  Soon after I bought a diesel generator (with advanced voltage regulation) as back up.  Could the generators have added to drop in performance of the batteries?

On December 10, 2016 at 2:36pm
Enda wrote:

Sorry, Advanced voltage regulator should read Automatic Voltage Regulator (AVR).

On December 13, 2016 at 3:44pm
John Fetter wrote:

Enda - Two hours at 62.5v is not going to help much.You need to CHARGE your batteries.I can tell you no more.

On December 19, 2016 at 10:15pm
Dattatray Badgujar wrote:

John, i am making a LA charger for 120 Ah. Other specs are as per this posts but want to know when should be the desulfating pulses applied to Battery? ie in the time between Fast charge to Slow charge or at the end of the slow charge? which method will help better to desulphating? As a process this ( pulses of high current) will be programmed every time the battery goes to charge , is this Ok?Pls advise.

On December 20, 2016 at 3:34pm
John Fetter wrote:

Keep the battery charged when not in use. Nobody has yet made desulfation work and people have been trying for over 100 years. If you want advice: Stop reading the ads.

On December 21, 2016 at 8:30am
Marduk wrote:

Before all the sulfate happens, what is the best way to stop it occurring in a new battery bank for backup power. I have 5, 12V 100 amp hr deep cycle flooded batteries. From the store I gave a commissioning deep cycle charge to 16V. The bank was discharged to 50% by the convertor , each battery delivering about 75 amps. Recharged and voltages 24 hrs later ended up higher than new. Strange. After full charge from store resting battery voltage after 24 hrs was 12.8V as measured, but after the first duty cycle and recharge they read 13.1 V.  In any case they are on a maintainer at 12.5V 24hrs a day. Anything else I can do to get an eternity from these

On December 22, 2016 at 12:33am
John Fetter wrote:

Marduk - Nothing strange about the 13.1 volts. Your batteries stood on the shelf for a period at the store. They were delivered to the store newly formed. It takes a number of deep cycles after formation and certainly after standing to bring the batteries “up to strength”. You can only hope to maximize battery life by not leaving them partially charged for extended periods. You absolutely MUST bring them up to 16 volts roughly every 2 weeks if they are regularly deep cycled. Deep cycle batteries often only reach maximum capacity after 100 cycles.You need to have at least 13.2 volts, perhaps 13.5 volts, as 24 hour maintainer.

On December 22, 2016 at 2:52pm
Nino Amarena wrote:

Dear Mr. Fetter; my son has a Jeep SUV that he uses for snow trips to the sierras in winter. Not a commuter car by far. He had purchased an Optima yellow top battery (size 34) about 2 years ago and last weekend he found it discharged to 5 VDC. Tried to charge it with a non-smart charger but it would not charge. He bought another Yellow top Optima and just placed it on the Jeep.
What is the best method to keep his battery charged and preventing problems? A trickle charge constantly of a couple hundred milliamps? A periodic charge every month?

Your advice will be appreciated,


On December 23, 2016 at 7:03am
Marduk wrote:

Thanks John for explaining the mystery of why the new batteries held a higher charge after the first duty cycle and recharge. I will take your advice and give them a deep cycle charge to 16V every few weeks, as the batteries will only be used in power outage. This all happens thru a automatic power transfer switch connected to the house fuse panel. The rest of the time they just sit there, connected to the inverter that has a large bank of 24V capacitors on it’s input across the battery bank. So all they do essentially is keep the caps charged until power is demanded. The inverter is fused at 400A on the positive cable. Thanks again John.

On January 14, 2017 at 8:27pm
Hugh5 wrote:

I have D8 battery on boat 5 years old
when fully charged with automatic 3 stage charger the specific gravity is only 1175 and the tested capacity by discharging at about 15 amps only showed about 30% capacity.
the battery voltage a day after coming off charge is 15.1 volts.
is the high voltage a sign of sulfation ?
will this battery high voltage stop the automatic charger form properly charging the battery.
should I force overcharge at 16v and for how long ?
how high a current should I overcharge ?
Hope you can help

On January 16, 2017 at 12:49pm
Arthur Schultz wrote:


There is no way that an 8D battery can give you 15.1V and at a specific gravity of 1175 you should see a voltage closer to 12.1V, if that. I saw exactly what you describe though, just last week. After changing the battery in the voltmeter the readings were normal.

It is winter and your battery may be cold. If so, you may need to charge much longer. Some chargers use timers for the high current stage. Some may get fooled by the higher resistance in a cold battery.

The same owner who needed to change his voltmeter battery last week wanted to zap his batteries to bring them up from 1160-1180. What he really needed to do was to steadily charge the batteries for up to a day and a half. Can you give the battery maybe 10A for 24 hours, or 20A for 12 hours?

If you are in a warm climate your battery may be dead. You overcharge a fully charged battery for brief periods to clean up minor sulfation. Your battery is nowhere near being charged.

On January 16, 2017 at 7:35pm
Hugh5 wrote:

thank you Arthur
I agree I cannot be getting 15.1 v that was a stupid typo. it was 13.7v after 3 days since being charged. still impossible but I used 2 different meters .the battery was at 20 deg F in a boat.
We cannot charge it at 10 amps because even at 16 volts we can only get 3 amps into it.
we tried 2 different 10 amp chargers and the max is 3 amps. however we have charged the battery now for over 20 hours and the Specific gravity went up to 1225 and the battery has warmed a little to 35degF. this is a mystery to us. I did read somewhere that a high voltage was a symptom of sulfation. I would love to force 10 to 20 amps into it and get it bubbling and warmed up but I do not have the higher voltage equipment to do it.
no doubt we need new batteries but I would still like to understand these voltages

On January 17, 2017 at 11:10am
Arthur Schultz wrote:

I live in coastal Alaska and I see charging problems in cold batteries pretty regularly. Boat batteries are often left to discharge, unlike car batteries that tend to stay topped off. If a battery stays fully charged, or close to it, then it tends to be relatively trouble free. A discharged battery may act like it will never hold a charge again.

If you started charging at 20 deg F and only reached 1175, then your starting point was somewhere very close to having ice inside the battery. Maybe the temp dipped a bit lower before you began charging. Did it form some slush? As it melted again the fresher water from the ice crystals may have stratified at the top of the electrolyte. Chemical reactions generally slow as the temperature drops and the lower specific gravity makes the water less electrically conductive. A discharged battery in cold weather has several problems that work together to prevent a recharge.

I’ve seen cold batteries that go to high voltages and seem to charge back up, but don’t really have much power. The voltage may drop very quickly as soon as the battery is used. I think that the plates hold on to some capacitance because of the sluggish ion movement through the cold electrolyte. try hooking some small 12V device to the battery and you should see the voltage drop very quickly to something more representative of the true state of charge.

On January 17, 2017 at 4:27pm
Hugh5 wrote:

thank you Arthur
excellent comments. so being cold does confuse things.
I am confident that the electrolyte did not freeze. but you are right we were very close.I put a 40 watt bulb under the battery tray to make sure it did not go any lower and since then it has reached 40F. Now after days of charging at 16 volts and 3 amps and it never changed .SG in the cells vary between 1240 to 1260 so we should be safe from freezing.by the way we load tested the battery at 100amps for 10 secs and CCA was well over 1000amps (rated is 1400) this was several days ago.l
Now we have turned our attention to the 2nd D8 battery which has been on charge for several days on the on board charger.. took it off charge and with about 10 amps of load (boat lighting) the voltage was 12.5v not the stupid 13.4 we had with the other battery. SG about 1180 corrected for temp and the battery temp 40F.
so we connected the manual charger which will equalize (Activate ) at 16 volts and expected the same 3 amps we got into the other battery. NO it went off scale. so we switched to manual 10A and it settled at 7 amps 12.3 volts. the 10 ams house load was still connected.
Now notice that the battery voltage was 12.5 volts on load and dropped to 12.3 when we started charging at 7 amps. this is stupid and surly defiies ohms law. we have left it on charge with this manual charger. suspect the on board 3 stage automatic charger is acting up.
I am a very practical hands-on electrical engineer and at this point I am screaming “black magic “. these lead acid batteries are worse than 2 stroke engines.
Hope I have not bored you.


On January 30, 2017 at 5:14am
shuja ur rehman wrote:

    i am from pakistan i want to know about battery terminals why the anode terminal of battery is more sulphated than the cathode the terminal
    In deep cycle batteries a tube exist tell me about this tube for what

On March 13, 2017 at 3:32pm
Dave wrote:

60 days ago I installed new 8D 12v/220ah batteries in form of two identical 48v banks.  Each bank is charged by a 50a MPPT solar charger and is kept in shelter where temp never goes below 50F.  They don’t seem to achieve full charge but charge rates drop from 40a in early am full sunlight to 1A about 1pm daily. Will only carry 6 hours of overnight load before switching to generator.  12 hour overnight load needs only 1/3 of rated battery capacity. Plates never lacked water coverage and look very clean,  Better late than never I guess, I did SG check and found 11.25 on both banks after 30 minutes rest absent charging and with12.5v terminal volts and small load of 8a.  Seems like it should be near 13.  Any suggestions will be appreciated.

On March 14, 2017 at 1:06pm
Arthur Schultz wrote:

11.25 isn’t a valid number. I’m assuming that you mean 1.250 if you are referring to specific gravity.

You don’t give enough of the details. Are the two banks paralleling? Each bank has 24 cells, so you have a total of 48 cells. You’ve given a single SG value when 48 are required. You also fail to give the maximum battery temperature. At 50° you will get some sluggish charging rates. From the very limited description it sounds like you’ve developed at least one bad cell on each bank.

On March 15, 2017 at 1:09pm
Dave wrote:

Arthur, thanks for commenting.  To clarify:
1.  The two systems including batteries, solar chargers and solar panels are identical and separate.  Both were bought and installed at same date and experience same environmental conditions. 

2.  I have checked 5 cells in each bank, SG is “1125”  +/-  a near imperceptible amount. 

3.  The 50 F low temp is experienced only at night when no charging occurs.  Charging begins by timer when full solar output is available and battery temp during this time rises to 60 F or more, continuing during the afternoon to maybe 75F on normal days.  I do not know max summer bat temp but the shelter goes to 90F sometimes.

4. Charge watts initially about 2,300 per bank, which drops fairly linearly over the course of 3-4 hours to near zero.  I don’t see any real difference in behavior between systems, they both include 2 axis sun trackers.

5.We had a cool winter, never freezing tems, any chance acid stratification, I’m just about ready to figure out a way to draw solution from the cells bottoms.  I’ve seen sulphated heavy crystals situations before on other occasions but these plates just don’t have that look. btw, I have checked voltage on all 8 batteries and they are within 0.05 to 0.1 volts, of each other when at rest , when discharging, and when charging.

On March 16, 2017 at 1:13pm
Arthur Schultz wrote:

How did the SG get so low? A fully charged cell in a new battery should be somewhere close to 1280. If 1125 is truly what you see then your bank is nearly dead, so you would need to push those 2300 watts for most of the daylight hours to finish the bulk charging stage.

The voltage is mostly irrelevant. I see wild voltage swings all the time that have no bearing on the actual stored power. A cool or cold battery often seems to charge rapidly, so it pushes the charger input back when it really needs a longer bulk charge. You have not mentioned whether any of your charging is temperature compensated. If your bank gets an initial charge at 50° and gets throttled back due to the internal sluggishness of the electrolyte, where does the rest of the power go? It seems like you have a reasonable charging capacity that isn’t going into the batteries.

To return to the SG, is “1125” really what you see, not “1225?” If you are reporting the correct number rather than a typo, then your batteries need to be seriously rehabilitated as soon as possible. I’ve had enormous trouble raising the SG in cool batteries with extremely low SG values. You’ve given a number that suggests an almost entirely depleted bank. At that value you would have a sulfation problem growing by the hour.

On March 23, 2017 at 6:14pm
Dave wrote:

Arthur, thanks. 
Your question about where does the rest of the power go:
1.  Even raising the bulk and float charge voltages to 15.5-16.0 volts doesn’t force more current into the batteries even though solar panel output is 78 volts at the same time.
2.  I am quite sure my SG number is correct.  After all, the weight in the hydrometer sinks right through Green, Yellow and all but one SG numeral in the Red zone. 
3.  Any chance acid stratification can account for this problem?  These suckers are so heavy I can’t see me shaking them to try to get better mixing.  I guess I could turn one upside down, drain the solution, then put it back in the battery.  Pain in the—-.

On March 24, 2017 at 9:29am
John Fetter wrote:

Arthur - The easiest way to mix the electrolyte without incurring a hernia is to gas them at 16 volts, (per 12 volt battery), for a few hours. They will get hot and they will gas furiously.

On March 24, 2017 at 12:48pm
Arthur Schultz wrote:

Not knowing your battery brand, I don’t know the depth of the electrolyte reservoirs in the cells. Some stratification is definitely possible. Like John said, you can mix the cells up by putting an equalizing charge on all of them. If you want a faster test you could get something like a turkey baster and spend a minute or two sucking and blasting the electrolyte around in a cell. That should be forceful enough to mix a cell thoroughly. It will give you a quick idea of whether you have been reading from a stratified layer, but I suspect that you need to give the batteries a long equalizing charge regardless of stratification.

It sounds like you have the voltage to equalize four batteries at at time. 62 volts and only 2-3 amps is enough power. You should beware though. The simple explanation here is that your batteries got into a sort of cold weather death spiral, where you kept draining them down, and the cool weather interfered with the initial bulk charging. What if something else was the cause? Suppose there really is a bad cell. You will be forcing the same current through the entire pack, but a bad cell may have higher resistance, causing it to heat faster. I’m leery of bad cells after a recent boat fire that was obviously caused by one bad cell in a battery. It shouldn’t burn if full of electrolyte, but might boil off the electrolyte faster. Just keep an eye on every cell. If you do four batteries at a time you’ll also be making enough hydrogen to cause a significant roof raising pop.

On April 3, 2017 at 11:19am
Malcolm TW Lawson wrote:

I have a RV with two 12v “house” batteries which are no longer holding charge.  I use the RV for about 2 months a year. About 10 days per year we are camping with no shore power and I need to run a CPAP machine at night for my sleep apnea. The inverter for the CPAP machine draws up to 10A.

I have found some 27D batteries that are quoted as having 180 min reserve capacity (= 75 AH ?).  The CPAP will need about 80 AH max which will give me about 50% of the capacity of the batteries.  I understand that AH capacity will depend upon current but I hope the excess capacity will take care of the non-linearity.  I wish the manufacturers would provide more data.

When it not in use,  the RV cannot be connected to power.

I propose to use the following protol:

If the RV is to be idle for more than a month I will remove the batteries and give them charge once per week.

Once per year I will give an over charge of 16v f or 200 mA or 24 hours .

After using the CPAP machine I will use the RV chassis alternator to re-charge since it will deliver more current than the charger connected to the RV 110v generator.

Does this sound OK?

On September 3, 2017 at 9:16pm
Seb R wrote:

Well this has made very interesting reading, lots of it too.

In (very late) reply to Enda’s questions, in particular #4,

Question 2:  Have the batteries now received a full saturated charge? Or is it just a 70% charge (as I read somewhere on this website)?

>Yes by the sounds of it those voltages are sufficient to give a full charge, not accounting for any ailments the batteries may or may not have.

Question 4: Does this correspond to 12.5% discharge (i.e. 48 V - 42 V = 6 V.  6 V is 12.5% of 42 V)?  Again, here, I appreciate that this is very simplistic and assumes that discharge is linear.

> No, far from it. 10.5V represents roughly 20% charge remaining, much less than I’m sure many would recommend on a regular basis if the wellbeing of the batteries are valued. I understand 12.4V represents 70% charge remaining and 12.6V 90% in a healthy battery. Any amount of battery defects/wear may effect these readings.
I avoid if possible taking my leisure/starter batteries below 12V, but mine are unfortunately sealed.

On September 3, 2017 at 9:23pm
Seb R wrote:

In the interest of sharing, here is a list of leisure batteries tested by partners of The NCC, compiled into three categories and ranked by the number of 50% DoD cycles before their capacity drops below a certain (?) threshold:


On September 4, 2017 at 6:16am
Seb R wrote:

The Number 1 performer in the NCC leisure battery tests is the Elfa Galax-E GLX-D, being 35% better than the Platinum Odyssey and 250% better performing than the next runners up.
I’m curious why it is so much better, a google tells that it’s a Lead-crystal battery. Further research suggests it’s an AGM battery which uses Silicone Dioxide as the electrolyte and 99% pure lead plates, others say lead-calcium-selenium plates.

All the hype suggests considerably improved lifespan and ability to tolerate discharge, as well as improved handling safety.

I would be interested to hear if anyone has any more information or experience on this technology.

On October 26, 2017 at 7:34pm
Barry Speronello wrote:

I’ve been using a brand name pulse desulfating charger/maintainer for several years with no luck.  My batteries are lasting no longer than they had with prior non-desulfating chargers, and a couple that were sulfated (would only charge to partial SG) were not recovered despite leaving them on the charger for several weeks.

Recently I got access to an oscilloscope and looked at the charging voltage waveform during operation of this charger and was surprised to see that it only pulsed during the initial charge.  Once the charger switched to maintenance mode it shifted to flat DC output.  This is despite the manufacturer’s claim that this charger/maintainer desulfates whenever it is connected to a battery.  I monitored maintenance mode for about 20 minutes with no change in this behavior.

Am I missing something?  How could it desulfate in maintenance mode without pulsing?  Also what size should the pulses be (these look like half wave rectified AC superimposed on the DC charging voltage).

On October 27, 2017 at 3:59pm
John Fetter wrote:

No one has ever scientifically demonstrated that pulsing works. It is possible to charge a battery with 100% pulses. Desulfation works inside peoples’ minds but not inside batteries. If you want to keep a lead-acid battery healthy, keep it on permanent charge at 2.25 volts per cell. After a deep discharge, bring it gradually up to 2.5 volts per cell, until the charging current falls off to a more or less constant value and then reduce to 2.25 volts. I have kept car batteries going for over ten years by doing this.

On November 17, 2017 at 5:43pm
rick wrote:

i happened upon this article and have learned much; thanks to all for the content; even the sometimes “lively” debate.

So there are obviously some who believe desulfating to be a fools game; others have a belief.  I’m good with either opion.

My question which I have not seen anyone ask (or answer); but it would seem to me that prevention of sulfation; as best that could be expected; starts with keeping your battery sufficiently charged; perhaps “perfectly” charged.  I have a motorcycle and classic car which see extended periods of time unused; be that a week at a time or upwards of a month.

I have been looking for a batter charger/maintainer.  What I think might be important is that chargers “profile”; be that the voltage it charges at, amp (i.e. c) rate, etc…  I would also guess that some might have specs that are not reflective of the chargers reality?  Perhaps I’m suspect.

So, whether a charger has some repair/pulse/recon/whatever mode or not; has anyone done any analysis of any mainstream chargers; specifically one which could be left attached to a battery for extended periods which might assist to extend the life of a battery (due to lack of discharge and/or desulfication if you feel that works)? 

I only have today a 20+ year old 2/10 amp charger.  Looking to replace that.  Seems CTEK, NOCO, BatteryMinder, Battery Tender, Schumacher (sp?), Optimum, etc… all look very similar by specs; though unsure of reality (again, regardless of marketing claims of recovery).

Any thoughts would be welcomed.


On November 17, 2017 at 6:03pm
John Fetter wrote:

rick - Use a timer that can switch on the charger once a week for, say, four hours. Take the voltage up to onset of gassing, and then switch off. That will keep the battery going for ten years.

On November 18, 2017 at 5:55am
Seb R wrote:

I can comment on the Halfords/Ring 8A charger (looks like a semi-circle with a flat bottom). It brings the battery up to 14.4V and them immediately switches to CV Float at 13.5V. No absorption mode.
According to figures presented across the web a CC Bulk phase up to ~14.4V charges a battery to approx 80%, leaving the CV Absorption mode to achieve ~95%. So you would have to leave that charger on Float for a long time to fully charge the battery.

Another one I have tried is this Chinese model:


It displays false Voltage and Amps. V I could understand as there may be some voltage drop, but false current? I requested a refund. I bought it as it will supposedly go up to 16.5V, which is true if there is low/no current flowing.

On November 20, 2017 at 2:32pm
Rick wrote:


On November 20, 2017 at 3:23pm
Seb R wrote:

John Fetter, I’ve been working on implementing your idea for a little while. The problem I find is that most chargers have their three stage charge control circuitry which doesn’t allow for much/if any gassing. I know you have suggested using a basic transistor rectifier charger for the job of maintenance but that doesn’t corrolate to battery charger makes and models.

Can you suggest a few models of charger you know would be suitable?

On November 21, 2017 at 1:53pm
John Fetter wrote:

I use a plain transformer-rectifier. I refuse to look at any complicated chargers. Waste of time. Designed and made by people who don’t understand lead-acid batteries. The only ones that seem to be available are expensive ones. That is the only reason why they are being sold. Because they are expensive, not because they work.

On November 21, 2017 at 7:41pm
Rosco wrote:

My advice to rick or anyone that wants to maintain car n motorcycle batteries. 13.5 volts. I use either a 13.5v switching adapter or a 14v switch mode adapter in series with a rectifier diode. The diode drops the volts by 0.5 and 13.5 results. There are several reasons that this is a great way to charge and maintain. Too many maintainers out there do not have a dependable float mode. Schumacher for instance. Some people think you cant get a battery to 100% full charge with 13.5v. In my experience it can be done. Just takes 12 to 48 hrs. A simple way to know when the battery is fully charged is plug your power supply into a watt meter. Over time the wattage required will drop to single digits, and a full charge will be reached when it absolutely will go no lower. Often batteries have one cell that ends up with a lower SoC than the other 5, and this is the best way i know of to get the weak cell charged without gassing the rest. Then once you get it fully charged that way, now is the time to take it to 15v or more to do the equalizing/ desulfating exercise. Just dont do that to agm batteries. Flooded only. Nearly all motorcycle batteries are agm so they cant spill acid. A knowledgable technician will know that vehicle charging systems are slightly over 14 volts. This is because there is often limited time to get the charge in. So there is a rubber band effect- more voltage equals a faster charge. Keep your battery topped off with distilled water. If it is the maintenance free type u can usually remove the sticker to reveal the 6 caps. With any luck your batteries can live 10 plus years.

On November 22, 2017 at 1:55pm
John Fetter wrote:

Sorry,13.5 volts is a float voltage, not a charging voltage. When a discharged battery is charged up to this voltage, it will partially charge, then the current will taper off and it will will never become fully charged. An excellent way to deliberately reduce the life of the battery. A lead-acid battery must be taken to a higher voltage for a minimum period of time, until the current tapers off and can then be maintained at 13.5 volts. The 13.5 volt float voltage must be temperature compensated. If it is not, the battery will likely eventually end up being overcharged or undercharged. Much better to take the battery up to a higher voltage once a week.

Applying 13.5 volts until the current tapers off and then increasing to 15 volts - as is being suggested - is the same as saying 13.5 volts will not charge a battery.

On November 22, 2017 at 7:18pm
Rosco wrote:

John- i want you to explain something. On a typical 50 to 100 AH battery once it is fully charged will still need about 100ma (0.1A) to maintain 13.5v. So any current that exceeds self-discharge of a battery will slow-charge the battery. If the battery has not reached full charge it will do so given enough time. Theoretically if a 100AH battery is at 50% it will require 50 amp hours to reach 100%. To do this with a 0.1 amp current would require ten hours for each AH, which is 500 hours. This is to illustrate that given enough time, a battery can reach 100% at 13.5v as the current will always have a minimum plateau. I realize this is oversimplified and likely the ideal float voltages varies. So my question to you is, how could it be that would not fully charge given enough time? Where is the 0.1A going? I think you claimed the battery would not reach 100% with 13.5v then a bit later claimed it could even be overcharged. I know you prefer the antimony alloy motive batteries but most of us Americans out here own more starting batteries than deep cycle. Some of us might have a golf cart or trolling motor with deep cycle but way more have tractors or equipment or vehicles that use starter batteries. My point is we have no control over what type of batteries they give us so we could use a little more info on how to maintain AGMs etc. Giving an agm a high voltage equalizing charge is a to damage it. Happy Thanksgiving

On November 23, 2017 at 4:07pm
John Fetter wrote:

Where is the 0.1A going? Into the battery.  A lead-acid battery that is persistently undercharged gets sulfated, reducing its ampere-hours. The charging current then simply makes hydrogen, oxygen and heats the battery.

” I think you claimed the battery would not reach 100% with 13.5v then a bit later claimed it could even be overcharged.” Move away from language and have a look at the technical factors: Batteries are not kept at room temperature. They are operated over a temperature range from as low as minus 40 degrees C to as high as plus 100 degrees C. A battery will not even remotely be charged when very cold, be undercharged at room temperature and will be overcharged when very hot.

Maintenance-free batteries were invented by salesmen, not by engineers.

On November 24, 2017 at 5:45am
Seb R wrote:

Rosco, there’s more to replenishing a battery than just refilling it with positive charge. Lead-Acid batteries have a lot of complex chemistry going on inside them, so much so that they are not fully understood by even the R&D departments of the big manufactures. But one thing that is understood is that the chemical reactions that take place during, and in the creation of, a state of discharge negatively affect a batteries lifespan and capability, and that this effect can be reduced by charging at 14.4V as apposed to lower charge voltages. This is aside from the topic of an equalising/desulfation cycle which can be beneficial in either case.

I learnt a lot about the chemistry of Lead-Acid batteries by specifically looking it up on pages on this website and in particular various pages on Wikipedia. I recommend you spend a few evenings researching, it is very interesting.

One interesting point you make is that 13.5V could be used to recharge a battery without stressing any unevenly healthy cells. I don’t need to point out what the result will be for the unhealthy cells in that battery but it’s food for thought.

On November 24, 2017 at 5:52am
Seb R wrote:

John, thanks for your reply.

Can you give me a couple of examples of a plain transformer-rectifier charger, just so I know I’m on the right track? Google images, ebay, anywhere will do.

On November 24, 2017 at 6:07am
Seb R wrote:

Rosco sorry, I got my cells mixed up. Healthy vs. Unhealthy. Still, interesting idea.

One more thing.

Regarding float charge, you asked: Where is the 0.1A going?
It’s being converted to heat. 1.35 watts of heat.

The self-discharge of a healthy battery is about 5% per month. A 100Ah battery sat open-circuit for one month would loose (5Ah x 12.6V) 63Wh per month through chemical reaction. 63Wh / (30 x 24 hours) = 0.04W.of self-discharge.

On November 29, 2017 at 8:42am
Rosco wrote:

I have already spent plenty of time researching. The commonly accepted 14.4v used in 12v lead acid charging is born from the assumption that the user wishes to get the battery charged reasonably fast without damaging it. But some users may have different goals. The OCV of full charge varies some, but 12.7 is generally accepted. Some users may value energy efficiency, and fast charging will waste more energy. Desulfation/equalisation and float current is wasted energy if not needed. Charging batteries at a lower voltage is more efficient. A figure i saw somewhere was that a flooded battery is about 70% efficient, meaning for every 100 watts you put in only 70 will be available upon discharge. This is partly due to voltage rise during charge and drop during discharge. That figure should improve some with slower charging. AGM batteries are more efficient on both counts but I share John’s dislike of AGM for most applications. If someone has the time to study lower charging voltages i’m listening. Charge a battery at 14.4v to 100% , let it stand 24hrs and record both OCV and SG. Discharge the battery to maybe 75% and this time charge it at a13.5v and maintain it until amperage has absolutely bottomed out plus 24 hours at least, then let stand 24 hrs. Then record OCV and SG again to examine whether SoC is as high as before. No need to input $150 worth of unneeded maintenance currents over the lifetime of a $100 battery, for example. From what i have seen sulfation is not as big of a battery killer as its hyped to be. Yes, its one of lead acid’s main enemies that could be avoided with paying attention to SoC, but i think a lot of the failures I see may come from someone having drained a battery enough to force at least on cell into high ampere reversal when they attempt to start engine.

On November 29, 2017 at 3:59pm
John Fetter wrote:

Rosco - If you want to understand batteries, you must work with batteries. The information that is commonly available about lead-acid batteries online is heavily influenced by battery cure merchants. The more you read online, the more confused you will become. Alternator regulators in cars are commonly set to 14.4 volts. The average car is driven for perhaps an hour or two a day. That means the battery is repeatedly heavily discharged and then put on charge for roughly 6% of the time. If a car is used for short trips, the battery ends up seriously discharged over time. If it is used like a taxi, the battery ends up overcharged over time. The 14.4 volts setting caters for “average use”. AGM has a third to half the life expectancy of a flooded lead-acid battery, and costs much more. People are inclined to forget to water batteries. I get 10 years out of a car battery. I buy only flooded and as soon as the warranty expires I break open the seal and water. I apply an equalizing charge every few months, charge to 16 volts, wait for the current to come down, and switch off. It is important not to allow charging to continue because the battery will get hot and then draw more and more current. If your battery is on float all day, 14.4 volts for 100% of the time will be too high. Starting the charge at 14.4 and charging until a couple of hours after the current has fallen, then switching to 13.5 can work.

On November 30, 2017 at 2:43pm
Seb R wrote:

My mind is turning, maybe you’re on to something. It may take a long time to charge fully, bearing in mind a standard three stage charge Absorption phase is considered to only achieve 95% SoC. It would be an interesting test, and would need a firm benchmark of “fully charged;” 3 stage with at least 24 hours on float, and 48 hours OC.

Rosco, have you heard of Peukert’s law? It is independent of energy wasted as heat.
One question I haven’t had answered on Peukert’s law is whether partial fast charging followed by sufficient slow charge to 100% would have the same effect as entirely slow charge. i.e. does fast charging “seal off” available capacity until the next discharge or does it only come down to the measured terminal voltage whilst charging. Common sense would suggest the latter, but I’m not so sure.. I think that’s a question that will make or break the idea of reduced charge voltages.

On December 4, 2017 at 12:45pm
Enda F wrote:

Recently, I got a new set of eight 6V deep cycle Trojan batteries (a total of 24 cells).
At 77 F the bulk voltage is 59.3 V.
At 50 F (temperature here at the moment) the bulk voltage is 61.1 V (according to Trojan: “Add 0.0028 volt per cell for every 1 F below 77 F).
The problem is my charge controller/inverter (all in one) can only be set to a maximum of 58.4 V.  How critical is the top end voltage?  In other words do I need to get a new charger?
If I need a new charger then I have a second problem.  The inverter part of my charger/inverter shuts off at voltages over 60 V.  If I get a new charger then when it charges above 60 V the inverter won’t like it.  Is it possible to use 1 or 2 diodes in series with the batteries to overcome this problem?  Any suggestions on typical types of diodes for such proposes?
(I know that the second problem is more an electronics one, but someone may have encountered a similar issue)

On December 5, 2017 at 4:22am
Przemyslaw Gieraltowski wrote:

Hello Jerry Malinski,
i am retired architect engeneer interested in electronics since teenage boy. I am very interested in Your experience and experiments with pulse desolvation of lead-acid batteries. Are You still on this forum?

On January 12, 2018 at 5:58am
Robin Brown wrote:

Hello. I live on a canal boat and have an obvious interest in battery life.
I have just come across this site but not yet read the whole script but would have thought it would be hugely useful to us boaters.
I have not however come across any comments relating to gel batteries which i currently run. [No pun intended]
Question one: Are they more or less like to suffer from “Sulphation” Any views please.
I have had the batteries i bought second hand for two years and run as 2 pairs of 6V.
Voltage at purchase was 12.6V per pair. For most of the last 24 months i have been shore connected with a trickle charge holding them at about 12,2V
When out cruising as i am at present the alternator charges at 14.3V However after charging the voltage quickly drops to around 12.3V and shows around 60% on the maintenance gauge.
Any explanation of what is happening to my batteries would be much appreciated.
Q2. Is it better too hold batteries in a float situation or allow them to discharge regularly to some predetermined level.
Forgive me if these answers can be found above but I am now very keen to learn as my second replacement appears imminent.
Finally although electrically aware I am clearly no cell expert. The anomaly that strikes me is that we tend to use Voltage as a measure of quantifying battery power or capacity.
Sure that relates to stating how high a water tank is above a water wheel without defining other parameters?!
Hoping for a reply. Robin

On January 12, 2018 at 4:21pm
Seb R wrote:

Hi Robin,

I think it would pay you to measure the voltage of each 6V battery individually rather than as pairs. This way you will see if one battery is unhealthy instead of taking an average reading.
After-all, all 6/12V lead-acid batteries are composed of 2.1V cells connected together.

There is quite a lot of mention to gel batteries on this website. It’s a difficult topic as results do vary, but my understanding is that expensive, purpose made, gel batteries can be far superior in terms of deep discharging (see deep-cycle batteries), while cheaper gel batteries can be false economy in most scenarios.

A note worth mentioning is that the majority of batteries marketed as “leisure” and “marine” batteries are as-near-as-makes no difference engine starter batteries, i.e. they don’t suit repetitive or prolonged discharging of any degree. For these purposes it would be wise to go for batteries specifically sold as suitable for prolonged and frequent deep discharges (see Trojan batteries).
For these purposes absorbed glass matt (AGM), and I believe gel, battery designs are mostly used. They do tend to be much less capable at high current applications (engine starting, etc).

Can you clarify; while ashore you have been trickle charging your battery pairs at 12.2V? This is considerably undercharged and will prematurely deteriorate the batteries. That would explain why they will no longer hold 12.6V/pair when given the chance.

Lead-acid batteries are complex creations and are widely misunderstood. A healthy, fully-charged cell voltage is 2.1V. While a l/a battery can be nearly completely discharged (if only once), a practical minimum cell voltage is considered 1.66V or 1.75V.
The voltage vs. capacity isn’t completely linear but you can get an idea of how much capacity you have in an otherwise healthy cell that is at 2V (12.2V). 80%.

The complexity comes when you try to measure capacity in a cell that has been maintained in a discharged state for a prolonged time and find that it is much less than that [80%] figure.

Good news though, 14.3V is a good voltage to be coming from your alternator.

For Lead-Acid batteries only; It is definitely better to leave them fully charged and on a suitable float voltage indefinitely. Any and all discharging creates temporary lead sulphate, some of which inevitably doesn’t make it back in to solution, and in addition to that discharging causes physical stresses within the plates which also contribute to the inevitable failure. What constitutes suitable float voltage depends on the temperature of the battery and the battery technology. I can’t say for gel (it is on this website), but for flooded lead-acid it should be 2.25V/call (13.5V/6) at normal ambient temperatures.

Finally, you make a very good point. Voltage is akin to tension, or pressure as good as. Capacity and current capability derived from voltage is a science, and difficult to get right. There are a few good write-ups on here and through Wikipedia on the topic. Cadex (here) have a novel product for just that. The only true calculation can be by carefully fully discharging a battery, but that’s a catch-22.
The pressure at the base of a water tank is independent of the capacity of tank above.

On January 12, 2018 at 4:43pm
Seb R wrote:

Enda F

Diodes could work. Take a look at RS components, they have a wide choice of diodes, some capable of high currents.

You want to consider three factors:

Vf (Voltage forward) = forward voltage drop, the feature you will is utilising to make the reduced voltage. Vf increases with current, the Vf figure listed will usually be at maximum current throughput. Vf/current curves will be in the datasheets for each diode. A combination of diodes can be wired in series to create a greater voltage drop.

Vr (Voltage reverse) = maximum voltage in reverse direction. You want to make sure the diodes can with withstand any reverse current. If Vf is exceeded the diodes will likely fail.

If (Current forwards) = maximum continuous forward current. You want to consider how many amps your inverter will use and make sure the diodes can handle that current.

Another option may be to make a voltage divider using some large resistors. But you may want to have an isolation switch to prevent current leakage when not in use.

On January 13, 2018 at 2:42am
Arthur Schultz wrote:


I do not want to claim a greater expertise than warranted but I’m familiar with cold weather charging problems in coastal Alaska. your situation of 50°F temperature isn’t terribly cold. I have temp sensors for two different chargers on my batteries and they do push the voltage up to compensate for cooler batteries. The charged ions literally need to move through the electrolyte and colder water is a bit more sluggish. Though there is physical movement, it’s not like you will see vigorous currents in your cells. It’s a bit more subtle. That movement will occur at a slower rate. It won’t stop altogether just because the liquid is slightly cooler.

Your batteries will indeed charge faster if you raise the voltage as they cool. They will still charge though at the lower voltage that your system produces. Simply extend the charging period if you can’t reach the recommended voltage. Also keep in mind that the act of charging the batteries may warm them a bit. It is the battery temp, not the air temp that matters.

On January 13, 2018 at 1:33pm
Enda F wrote:

Seb R
Thank you for your help - it is much appreciated.
I hadn’t thought of the voltage divider.  It gives me something to think about.

On January 14, 2018 at 3:00pm
Robin Brown wrote:

Thank you Seb R.
Your response has been most helpful and given me plenty to think about and research [Not least on this marvellous site] to pursue.
When you say please clarify presumably you mean precise Voltages?
I am still away from my shore base but planning to return shortly when I will start investigating further. I am certainly suspicious of the accuracy of the battery indicator gauge and intend to fit a more accurate one.
To inform my discharge data.
12V LED lights. Unsure of total wattage. Water pump to sink etc.
Fridge freezer which is only mains so constantly running through the inverter. Fridge rated at 80W with average of 20W but of course this must depend on frequency of access.
Would a smaller inverter say 200W capacity and dedicated to the fridge be more efficient than running the 3KVa main boat inverter?
When I use larger appliances such as hoover, coffee machine toaster etc I ALWAYS run the engine when I believe the secondary alternator output is in the region of 120A. 
Clearly I have a lot of investigating to do but thank you for support to date.

On January 15, 2018 at 6:17am
Enoch Cha wrote:

Dear Mr. John Fetter,
Thanks for all your working in this batteryuniversity.com, very iinformative when i read all the forum especially in this desulphation method and how to prevent.
Finnally i found what i can do with all my car battery.
Thanks again for your research and information you give us for free in this forum.
Enoch-Jakarta Indonesia

On January 18, 2018 at 6:11am
Seb R wrote:

Hi Robin,

Yes a smaller, dedicated, inverter will probably use less power overall. When they specify an inverters’ efficiency (around 85% usually) that is while running at it’s optimum. Much of the inverters circuits will consume power while on whether there is anything running off it or not, so the efficiency will reduce considerably with a smaller load (say 80W vs. 3000W).
You could connect any inverter to a 12V current meter and turn it on with a 60W lightbulb plugged in to measure the energy loss. In an ideal world it would be (60W/12V) 5Amps.

It is best to measure the voltage of batteries when there is no load (at all) on them. Disconnect one terminal from each battery before measuring.

As long as your batteries can maintain a healthy voltage after use, and they have the means to fully recharge before too long, then you can use a large a load as you like (hoovers etc). For the time being though, see about those batteries and charging voltage.

I mentioned to clarify in case it was a typo (12.2V took me by surprise!).
I came across a small car battery charge once that thought it had finished charging a battery once it got it to 12.6V instead of 14.5V. They aren’t all good.

On January 19, 2018 at 12:37pm
Enda F wrote:

Arthur Schultz, thank you for your help.  It doesn’t get too cold here, certainly not by Alaskan standards.  My real difficulty at this time of year is trying to bring the s.g. readings back up above 90% after each recharge.  You said ‘simply extend the charging period’.  Do you mean to extend the bulk charge phase or the absorption phase?  I am guessing that extending the floating phase won’t make much odds.

On January 19, 2018 at 3:32pm
Arthur Schultz wrote:

While bulk/absorption/float charging is nice, don’t get too caught up in minor details. Bulk and absorption can both be extended. You could stay at absorption voltage for a month and merely use a bit more water.

Overall, my experience indicates that as the battery cools you have way more leeway to push power into the battery. There is a strong tendency to undercharge. Its fairly difficult to overcharge. You are finding this on your own. Get a good refractometer that can accurately read the specific gravity. Then push some voltage and watch it. Depending on the amps, temp, and cell sizes, you may find that a warm weather bulk voltage can be your absorption voltage. Since most of the world’s heavy machinery uses a voltage close to your bulk stage, you shouldn’t be too worried about harm to your batteries. The odds are that you will do more damage from undercharging.

On January 19, 2018 at 4:53pm
John Fetter wrote:

If you want to know if a lead-acid battery is fully charged or not, simply put it on a C/50 charge and watch the voltage. The voltage of a fully charged battery will rise to a plateau which will be in the region of 2.55 to 2.65 volts per cell. It might take a while. A battery that refuses to go up to 2.55 volts is either significantly discharged or ready to be replaced. Don’t carry on charging when the battery gets rather hot

On January 19, 2018 at 8:12pm
Robin Brown wrote:

Seb R Thank you for your last post. I am now back at shore base having been out for about 10 days. Not feeling brilliant so as yet havent been down into the engine bay to explore individual battery voltage BUT the batteries are now floating ai 13.2V practically I volt above what they were floating at before I went off grid. [ 10 days recharging the batteries day and night.
The battery condition gauge which was part of the solar panel installation now seems to be holding at 63% much lower than before the trip.
This is all very confusing to me.
Oh and the battery voltage drops to 12.9V from 13.2V after an hour when the Victron charger is switched off.
In summary it seems as if the batteries have benefited from the trip out.
When Im over MY bug I will report the individual battery voltages as suggested to help build a better picture of what is happening. My feeling is that my 6V series / parallel wired Snnenshine batteries are in better condition than I feared.
Thank you for your advice and support in the meantime.

On January 20, 2018 at 12:47am
Arthur Schultz wrote:

John Fetter:

At what temperature? I’ve found that the apparent voltage of a lead acid battery is highly temperature dependent, and not just when measured on an isolated battery. The charging voltage can also appear to hit whatever peak the charger is set to hit, while the specific gravity does not rise to match.

I’m not talking about any extreme -40° temperature. I rarely see temps below +10° and most winter battery temps fall into the 20s and 30s. At 30° this 2.55V plateau may never be seen if a battery bank get used regularly. You simply won’t have time to reach it. A cold, discharged battery may see a rise to a plateau again and again without actually reaching a full charge.

In the end it is so much easier to use a refractometer to measure the cells’ electrical potential than to wait for days for some plateau.

On January 22, 2018 at 3:15pm
John Fetter wrote:

If you are continuously deep cycling flooded lead-acid batteries and you find that the way you are using the batteries is preventing your batteries from reaching 2.55 V at NTP, then your batteries will not reach full state of charge.

On January 26, 2018 at 3:43am
Enda F wrote:

Thanks again - I am slow to reply as I don’t always get notifications to my email.
Judging by the sg readings I have always been able to keep the SoC of the batteries around 75% to 85%. 
The charger I have charges the batteries from solar panels or from a generator - I am off grid.  The charger has one algorithm that it follows and all I can do is change the values for the bulk voltage and the floating voltage.  I can not change the times for bulk charging or absorption.  I am limited in what I can do.  I suppose I need to consider a new solar charger. I am not sure if you rely on solar energy, etc. or not but if you have any suggestions on make/model of charger I would appreciate it.

On January 27, 2018 at 2:26am
Arthur Schultz wrote:


I live in a pretty cloudy climate so solar panels are not so practical. Since my boat isn’t connected to shore power, and some times spends months away from home, I am familiar with the problem of unreliable charging sources. Your 60V system uses different equipment than the stuff I see. I do have one suggestion though.

I put an external Balmar type regulator on my alternator. It does have settings to adjust voltage and charge time before falling back to float voltage, but some times I was starting with a cold boat or depleted batteries. It wasn’t easy or desirable to continually adjust the regulator settings. I had added a power switch on my main panel to kill the alternator, just in case I had some odd reason. The regulator began its programmed cycle every time it was turned on, so I could extend the bulk charge by turning off the alternator for a few seconds and repeating the cycle.

Something starts the charge cycle on your charger too. Do you have a way of restarting or repeating the cycle before it finishes, to extend the bulk phase?

I don’t know where you are located, but maybe you could look at golf cart chargers. I fixed one for an in-law about a year ago by upgrading and cleaning the battery wiring. It had a set of Trojan batteries and some kind of charger I’ve never seen before. Very much like John Fetter’s 2.55v/cell advice above, the charger pushed right past what I expected. I was pretty worried for a few minutes until I decided that it did something like an automatic equalization on each charge cycle. I didn’t deal with the charger other than to monitor one charge after my repair job, but it didn’t seem to pay any attention to the notion of bulk and absorption. It just raised the voltage and tapered the current until it reached an equalization voltage and turned off.

On February 12, 2018 at 2:58pm
Enda F wrote:

thanks again for your reply.  The charger I have is designed for solar charging.  When it starts its cycle and is interrupted by heavy cloud (for example) it just continues on where it left off (more or less) when the cloud has passed.  When it has completed its cycle it doesn’t start a new cycle until the voltage on the batteries has dropped to a certain value.
I suppose my best bet is to get onto a solar forum and see what others use.

On February 24, 2018 at 4:09am
Bob LaFrance wrote:

I have a 2 month old set of Die Hard deep cycle batteries.  It is in 4x4 matrix for 48v.  They don’t seem to be holding a good charge.  I expect they are being undercharged and maybe sulphated.  The batteries are in the basement so basically 70F.  I am using a generator and a pair of Schumacher 48V/25A chargers to charge.  I connect each charger at opposite corners of the matrix so charge is very well distributed among all batteries..
I noticed that the chargers do not have remote sensing. I expect this may be the problem as maybe I don’t get such a high current at 14.5V-14.8V. 
I have a pair of Kepco power supplies that are good for 30V at 40A with remote sensing.  I can set up to run a higher current at 14.4V Would this help? 

Thank you for your assistance.  Your site is great.
Bob L.

On February 27, 2018 at 5:51am
Bob LaFrance wrote:

Update - I pulled one of the batteries out of the matrix and baked it for an hour at 16.2V.  It took about 9amps.  Cells were obviously bubbling.  I then hooked battery up to 1 ohm resistor for discharge.  The battery ran for over an hour before it went below 12.0v.  This was quite a bit longer. I have a data logger so was able to record.  Today I will bake some more while monitoring the SG.  Any input from your end would be fantastic.

Thanks again,

On March 5, 2018 at 8:26am
Santiago wrote:


I’m amazed about how much info is in this single thread.
Reading for some days i learned couple of important things about using lead acid for solar systems.
Thanks everybody for the good info.

I have a question:
John Fetter sugested a method to see if a battery is fully charged:
“If you want to know if a lead-acid battery is fully charged or not, simply put it on a C/50 charge and watch the voltage. The voltage of a fully charged battery will rise to a plateau which will be in the region of 2.55 to 2.65 volts per cell. “

Could this method be used to know theal capacity of a battery?
Let’s say i have a battery i’m sure is fully charged.
Then i put a current so it stabilizes at around 15.5 V…
Can i determine the real capacity of that battery is around 50*current?

For example ( for a fully charged bat.) i put 1Amp…. afther 1 hour or so it reaches 15.5V and keep there.
Real capacity if this bat. is around 50AH?

On March 5, 2018 at 4:36pm
John Fetter wrote:

The rate of self-discharge of a battery goes up as it ages, especially during over-charging. This can eventually make it impossible to get the battery voltage up to 2.55 to 2.65 volts per cell at C/50. There is only one way to measure the capacity of a battery. Run a discharge test.

On March 6, 2018 at 11:50am
Santiago wrote:

Ok. I understand that the only way to actually measure the capacity is: measuring it.

And i see that it works the other way around:
Whith aging self-discharge raises, so you need to put more current to get around 2.60 V per cell “looking like” it has more capacity when indeed in can have less.

But what i ussually see in old batteries is internal resistance increased, so with little current i get high voltages very fast.

Could happen that internal resistance compensates somehow self-discharging so i get a nice ~2.60V / cell with C/50?

Or they are mutually exclusive?

As i see it, increased sel-discharge should be the consecuence of some low-resistance path inside the cells…

.. too many questions come to my mind

John, thank you very much for all the excellent info!


On March 6, 2018 at 5:01pm
John Fetter wrote:

A 12V battery consists of six electroplating cells connected in series. Lead metal from the positive plates is electroplated onto the negative plates. Metal impurities are electroplated onto the negative plates. However, lead is only very sparingly soluble in battery acid, hence the lead electroplating proceeds at a very, very, very slow rate. Most metal impurities are far more soluble and will plate onto the negatives more quickly. The metal impurities do not plate on smoothly but on extremities, setting up perhaps millions of minute shorted cells on the surfaces of the negative plates. This causes the cells to self discharge.

On March 12, 2018 at 1:00am
John McLean wrote:

Thanks for a great site. So much to learn and then I’m not sure I’ll know many of the answers. I’ve got an RV in Europe and 2 cars in Australia so I’ve always for battery dilemmas. I was about to buy a few Megapulse units but will now hasten slowly after finding this website . John Fetter you’d tell me to keep my money in my pocket I’m sure

On March 12, 2018 at 4:35pm
John Fetter wrote:

Technical advice, perhaps yes. Commercial advice, definitely no.

If you must leave a vehicle unused for months, use a charger that maintains the battery at 13.5 - 13.6 volts.

On March 27, 2018 at 7:30am
Charles wrote:

I am a current sub electrician with a background in flooded lead acid batteries back when we still used them.

I’ve been volunteering at a local soccer club that uses a golf cart with 6x6v batteries in series. I had been told it had poor performance and figured I’d check into it for the folks. After looking, I noted all cells were (very) low on water and, in asking, was told no one had ever maintained the cells. I managed to add between 2.5-3 gallons of DI just to get the electrolyte back just above the plates. No jars are bulging… though there was some electrolyte across the top of all cells with some buildup at the terminals which I neutralized and then scrubbed/washed.

I’ll need to take some voltage measurements as well (I have yet to do so) and had just watered the battery on a whim yesterday when I saw all the plates looking dry and also need to get a real hydrometer that quantifies SG as the one at Wal-Mart was just a qualitative 0-1/4-1/2-3/4-full measurement… but it’s what I had at the time. I checked after watering… all came back ‘dead’... though I imagine I wouldn’t get a good reading anyways because I’m dumping light water on top of heavy acid. I left it to charge. It had been on the charger at minimal amps before I started and, when I plugged it in to leave… it looked like it was accepting more charge… as it was hovering around 6-7 amps after an initial peak when I first plugged it in. I do have a Kill-A-Watt plug in I suppose I could use to try to quantify the amount of power that is being consumed to charge it… though I’d expect a good portion is lost in the conversion from AC to DC and the chemical process itself… and once it’s on a float it’s probably making a minimal amount of gas and heat.

All cells are date coded K15… so at ~2.5 years… it’s not very old (in reading.. .they seem to last ~5 years of moderate use if maintained… with ones that are used lightly, they seem to go upwards of 10 years) ... but it’s obviously not been maintained at all. Other than raising it’s water to the proper level… allowing it to charge… is there any other method that could be used to help restore the battery capacity? I figure the act of sloshing the electrolyte up[ the dry cell has allowed the plate to discharge down it’s length and built up a layer of sulfate… plus only a portion of the plate having to take most of the charge/discharge reaction would not have done it any favors.

Still… it’s a not-for-profit club who’s only revenue is the kids registration and decent batteries aren’t cheap and if I can get more acceptable capacity and extend it’s life… it helps keep costs as low as it can be. It doesn’t need to be 18-holes-of-golf kind of capacity (whatever that is… I’m not a golfer) they mainly use it to ferry around some elderly folks around to see their grandkids and move some stuff around intermittently through the day. I doubt it sees more than 3-5 miles of use in one day. Generally speaking, it will sit on it’s charger several days to a full week w/o use.

Any suggestions beyond watering to the correct value and allow it to charge/discharge to exercise the plates to whatever capacity might be left is appreciated. I’ve watered a few automotive batteries and the ones on the boats many, many times and am familiar with charge regimes of flooded lead acid batteries and VRLAs so far as the navy is concerned but I’m not sure about correcting a battery was hasn’t been maintained and has gone effectively dry.


On March 28, 2018 at 11:43am
Faisal Raza wrote:

Dear friends,
This is Raza, we belong to a very hot area, we face lot of power shut downs on daily basis, we have to use UPS for alternate power supplies, in very hot days our fans work continuously 24 hours a day. When power shuts down our UPS start supplying electricity to our electric equipment but in very hot days like June, July and August the power shuts every after one hour, it means that for one hour, UPS charge the batteries and next one hour the UPS provides the stored power to the equipment specially fans and lights.
So to maintain the health of power batteries it is a big deal for us, our batteries life ends very soon because during very hot months the battery charged and drained and then charged and then drained, this process overloaded the batteries and it is a continue process. It is end less in whole Summers, our battery exhausted due to this very hot weather and further the on and off and on and then off, that ends its cycle life within two years.
one of my friends bought two maintenance free batteries and the same happened again, the batteries stopped working within 2 years, all the gel dried off. due to 35 to 45 centigrade average temp. and 50 centigrade for few weeks,
my friend disposed off those old batteries and bought two new batteries, this time he put these new batteries in plastic containers with normal water about 4 or 5 inches high in those containers. I don’t know why did he do this experiment but in result after 4 years the two batteries are still in working condition.
my question is,
how comes batteries remain OK in water?
If the answer is yes, can we repeat the same experiment with lead acid batteries?
is this a dangerous experiment?
one logic that I could get is, the water keep the batteries cool and due to this the gel remain in wet form and batteries life cycle extends.

I am waiting for your replies, for further understanding.

Thanks and Regards

Faisal Raza

On March 31, 2018 at 4:54pm
shawn kelly wrote:

Re: Charles - I am fellow submariner and I understand you are actually looking for a way to bring back life into a lead acid battery - you mention sloshing around and even going in and scraping plates - WAY TOO MESSY.  I have been using High Frequency Mechanical Stimulation on both FLA/VRLA and several LI-ion derivatives and getting great results.  It is like a battery renewal on life.

On April 3, 2018 at 3:23pm
Charles wrote:

“you mention sloshing around and even going in and scraping plates - WAY TOO MESSY”

I think you misunderstood what I was talking about.

“All cells are date coded K15… so at ~2.5 years… it’s not very old (in reading.. .they seem to last ~5 years of moderate use if maintained… with ones that are used lightly, they seem to go upwards of 10 years) ... but it’s obviously not been maintained at all. Other than raising it’s water to the proper level… allowing it to charge… is there any other method that could be used to help restore the battery capacity? I figure the act of sloshing the electrolyte up[ the dry cell has allowed the plate to discharge down it’s length and built up a layer of sulfate… plus only a portion of the plate having to take most of the charge/discharge reaction would not have done it any favors.”

I was discussing the method by which running the cells dry have had a negative effect on the cells when people has run the golf cart around and that bit of sloshing through movement has likely greatly affected the upper portion of the plates. You’ll layer sheets of Lead sulfate… but be mostly building up unequally at the bottom. When you’re charging and the cart is still, you won’t have the ‘sloshed’ part of the cell immersed, and the lead sulfate layer will stay. The gassing will raise the electrolyte level *slightly* from the gasses displacing the electrolyte, but it’s negligible.

I have no intention of shaking the cells as filling them and charging and letting them gas mixed the electrolyte. I do not intend to cut open the jar… remove the separators and scrape the plates either… nor had I alluded to that from what I recall writing. While I suppose that could work… trying to cut up, dismantle, refurbishing by removing the top later of the plate and reassembling isn’t something I’d *ever* be interested in doing.

Searching, “High Frequency Mechanical Stimulation Battery” yields essentially no results on a google other than things related to TENS units and one thing on LION batteries in the first handful of results. If this is a fancy term for pulse charging… then I have read on it and am somewhat familiar.

Since my original post, I brought the electrolyte up to the proper level following a charge where the electrolyte was slightly above the plates. SGs with the crap qualitative hydrometer is ‘full’ (4 balls floating). Final total was adding 3 gallons to what are GC2 cells… so .5 gal a piece. I’m not sure what their total capacity is… but they had to be awful low.

I’ve done what I can for the people. I’ll let them use it and see if it has enough capacity to get through a Saturday of soccer games. Whether it’s capacity was negatively effected or not… if it does the job, then that’ll be good enough. I figure cycling the battery may allow some of the buildup on the upper portions of the plates sort themselves out. From taking it with the battery charged but low… watering it… and hooking it back to the charger and seeing the charger go under load and maintain a decent charge current gives me a good feeling it’s going to be somewhat better. Those amps had to be accomplishing something.

I do appreciate the response… and I appreciate your service. I’m effectively done with what I’ll do… past allowing the cells to cycle and perhaps experimenting with a pulse charger, though I think the cycling will yield the main benefit. I’ll check load voltages under heavy use and SGs during discharge… along with ICVs during recharge to see if one cell is very poor and dragging the rest down, or for the ICV peaking that occurs on a problem cell. Considering the SGs looked good, as rough as the hydrometer I was using showed, and the ICVs resting were almost dead on the same gives me some hope it’ll be good enough to keep going awhile longer with acceptable capacity.

It hasn’t been used for a game day (spring break) but in a little running around the field for maintenance this weekend… I’ve been told the cart runs much faster… showing the cells are able to hold their voltage under load much better. Good signs. I’ve got my fingers crossed.

On April 12, 2018 at 1:33pm
David Paton wrote:

Mastervolt 225 AHr AGM battery failures
We have a large pleasure cruiser, which uses six of the above batteries, in a series/parallel configuration, giving supposedly 675 AHrs, at 24 volts, for house supply, being charged by a Mastervolt 3 stage battery charger, and giving 240v supply thru a 5 Kw Mastervolt inverter
First set of 6 batteries lasted about 2.5 yrs, the second set gave indications of loosing charge after about 9 months
Mastervolt have refused to agree to warranty, even thought their website states 2 yr warranty, and are telling us the batteries are sulfated
When not being charged by the generator on board, or one on the Volvo Penta alternators, when we are motoring, the house batteries are charged from shore power
Any comments ?

On April 12, 2018 at 2:42pm
Seb R wrote:

David Paton,

It sounds like either Mastervolt are producing very poor quality batteries or your charging systems or usage pattern needs refining.

I would suggest getting a multimeter/voltmeter and measuring the voltage the batteries settle to after being fully charged and subsequently left entirely disconnected for 24 hours, as well as the voltage that your charging systems are putting out to the batteries with the batteries connected and reasonably charged, as well as the voltage you allow the batteries to run down to before charging (both regularly and on irregular occasions).

The first thing I suggest to measure there, the charged voltage of each battery, must be done on each battery individually as if one battery is faulty then it will not be obvious from a reading across all batteries as the total voltage will be an average.

Once you have all these measurements, write a clear and concise email/letter to Mastervolt (with pictures if possible) and they may well change their stance on the warranty issue, if they are still liable.

On April 12, 2018 at 3:36pm
Arthur Schultz wrote:

David, count yourself lucky that you got so much life out of the first set and then rearrange your house bank into something more appropriate.

I see this type of problem again and again. You should never use AGM batteries on a boat. No matter what the manufacturer says, you should never use them on a boat. No matter what you see others doing, you should never use them on a boat.

When you arrange any lead acid battery bank in a parallel configuration you invite premature failure. That is the most critical problem. You magnified the problem by making three paths rather than the more common twin path. If you are fastidious you can limit the damage by regularly isolating the parallel banks and equalizing them. On most boats this is fairly difficult. On your boat it isn’t an option since you shouldn’t try to equalize AGM batteries. This is only one of several reasons never to use AGM batteries on a boat.

I just spent 3 weeks installing a new DC system on a boat. The customer spent thousands constantly replacing batteries. This time around I gave it proper charging capacity and I installed a house bank of 415ah 6V batteries. There are also a pair of starting batteries that are easily isolated with rotary battery switches when the engines are not in use. The large 6V batteries give a single path for charge/discharge/equalization, and they are far cheaper. They also accept a higher charge rate than AGM. You could have 4x of the 6V batteries to make a 415 ah 24V system for about $1300. I’ll bet you spent more than that on the AGM batteries.

On April 28, 2018 at 9:08pm
Wes wrote:

It was not my intention to post in the forum at this time, but I was looking for your CONTACT, and didn’t see it, so I decided to just do an introductory post for now.

Later on, I will describe myself and give you more information, but I think I need to at least tell you why I am posting now.

I think Eureka! I think I have found out how to overcome the problem of sulfation very easily. No pulsing, no addition to electrolyte, no magnesium sulfate, no cadmium, none of those. I was able to resuscitate two batteries that were dead for at least 10 years. When I first checked the voltage they were reading around 0.4V. I tried to charge them, and one of them would not accept any charge. Now I have two fully charged 10 year old batteries.

Now, I cannot say for sure that the batteries were sulfated. However, I think most people will be leaning toward that possibility. In any case, I think I would be able to bring back to life any battery that is in good mechanical condition.

Many people have come up with solutions from time to time and they turn out to be duds. So far, my solution looks pretty good to me and I am hoping it will be found to work well.

I cannot disclose the solution at this time, as I am considering whether I should have it patented. If I decide not to have it patented,then I will most definitely share it with you guys soon.

On April 30, 2018 at 1:55pm
John Fetter wrote:

Wes - Suggestion. File a provisional patent.

Have you checked their capacities?

On May 1, 2018 at 10:11am
Wes wrote:

Thanks for your response John. What you said about the patent, was what I wanted to contact the forum about, to ask whether the Idea is patentable. It is only a method, a process and so I am not sure if a patent can be granted for just a process. Furthermore, if I patent such a simple process, what value would it be to me; It would be hard to exclude anyone from using and abusing it, because it is so simple.

Now John, what is the difference between a Provisional Patent and a regular utilty patent?

On the question of testing the capacity, I have to tell you that I have no formal means for testing their capacities. I used the big spark test, and they appear to be strong sparks like a new battery would give. You see, I just started to look into lead acid batteries about a week ago and this only came up because my car is parked most of the time and the battery kept going down. I found this forum and spent some time finding about sulfation and its possible solutions. As a matter of fact, I still don’t even have the time to get a grasp of the chemistry inside a lead acid battery. I came up with my idea because I’ve been working in electronics for more than 40 years and I remembered a bit of high school chemistry.

The process I have come up with was born out of hunches and still need to be validated by guys like you who seem to have vast experiences with batteries.

On May 1, 2018 at 1:55pm
John Fetter wrote:

Wes - A provisional patent is completely secret, not published, and gives you a year to work on the idea, before you you need to apply for a non-provisinal, patent. All patents for new ideas for apparatus or method are utility patents. If you are a US resident, you can opt to keep the non-provisional application secret PROVIDED you do not apply for a PCT, which is the route used to apply for international patents. However all granted patents are published upon grant, and all non-provisional patents destined to become PCT are published after 18 months.

A capacity test is simply a test with a load. The load is a resistor with a value that will discharge the battery within 20 hours. Simply use a heater bar or two or three, and tap them to adjust the resistance. They will get hot. You can use car headlights to discharge the batteries. Don’t need the fittings, just the lamps and solder the wires to the lamps. If the lamps stay on, you have an invention. If the lamps come on briefly, you don’t have an invention.

On May 1, 2018 at 7:10pm
Wes wrote:

Thanks again for your reply John. I will definitely consider the provisional patent after I do the capacity test you are suggesting. I will keep in touch with you guys if that ‘s OK with you all.

On May 11, 2018 at 2:44pm
Utah Engineer wrote:

Previously worked for a battery recycling and smelting company in the US ... way back when I first got out of college.  Actually worked for the R&D department ... and we were many times involved with the destructive analysis of batteries that experienced premature failure.  I can also verify that battery manufacturers truly survive on the replacement battery market.  If electrochemical-induced cycling problems did not cause the battery failure within the first 5 to 7 years ... then vibration-induced long-term structural integrity flaws caused the failure of the battery shortly after.  Just like when the rubber tire industry introduced a hard compound lasting over 100k miles on a car ... that product went away quickly when tire replacement sales went down. wink

On July 3, 2018 at 9:51pm
Sam wrote:

Has anyone tried BatteryMINDer or Pulsetech chargers/desulfators ? Both companies make chargers and both make on board desulfators only. Many people claim these could restore batteries.

On July 3, 2018 at 10:07pm
Sam wrote:

Hey Wes, any updates on your venture?

On July 5, 2018 at 10:54pm
wes wrote:

I have decided not to patent my idea and will soon describe what I have come up with. I have just returned from a 3 week vacation abroad and I am a bit exhausted. I need a few days to recover and then I’ll tell what I have found.

On July 6, 2018 at 9:02am
John Fetter wrote:

You found out it does not work, or in the years to come, you will become the most unhappy person on earth and be living with the realization you made a very bad decision.

On July 12, 2018 at 11:56am
wes wrote:

Some weeks ago, I declared on this forum that I had discovered a way to reverse the problem of battery sulfation. At the time, I was considering whether I should patent the process, but after further consideration, I have decided not to and I am now disclosing it on this forum.

Let me preface this disclosure by saying that I am not a chemist. I came up with my idea from electrolysis learned in high school chemistry and a hunch that it might work.

Here is what prompted me to get involved in the discussion; I noticed that my car would not start as the engine would not turn over after it was not driven for a week or so. This happened repeatedly. Eventually, I decided to check the current drain on the battery when the engine was not running. The drain was in the order of a few milliamps. I therefore concluded that the problem was due to the battery and not the current draw.

In order to educate myself a bit about the problem, I went on line and there I found out about sulfation for the first time. I had never looked at batteries before, so this was my initiation on the subject. After reading as much as I could on line, I came to the conclusion that there must be a chemical solution to this problem and started to experiment soon after.

Without further ado, I will describe what I did.

First, I set out to find some very old car batteries that were dead for years. I did not realize that these would be so hard to find. Most of the batteries I got were more than 10 years old. I made sure that any battery I decided to use in the experiment was reading no more than about 2V if any voltage at all. Also, I made sure that there was no leakage of acid and that the batteries were in good mechanical condition.

Now, here is the “fun” part.

The battery is first hooked up to a charger to see if it will take and hold a charge. I would say that if it does not take and hold a charge within 2 hours, then it is a good candidate for the experiment.

A high wattage resistor or lamp is connected in series with a battery charger and the +ve output is connected to the -ve terminal of the battery. A resistance of about 2-3 Ohms is a ballpark figure. The-ve output is connected to the +ve terminal of the battery.The charger is turned on and the battery is left to charge. It might take a day or two or maybe more to charge the battery in reverse until it reaches around 12V and holds its charge.

After the battery has been charged in reverse, it is now ready to be charged in the normal way. The previous connections are reversed and the battery is allowed to charge. Again, this is likely to take a day or two, or maybe more, depending on charging current and voltage. These operations will require a current and voltage meter. Charge the battery until it able to hold a voltage of about 12.6V.

Obviously, changing the battery acid might help to improve such an old battery. This and many other things might help to improve this process. However, I have not spent time (which I cannot afford) to look further into the process.

In conclusion, let me say that this idea just came from a hunch and I used my high school chemistry as a basis for trying to put my idea to work. I am by no means a chemist. I just thought that reverse charging the battery might cause sulfates deposited on the plates at the wrong time, to be removed by reversing the process of electrolysis. PLEASE chemists and physicists, rescue me.

On July 12, 2018 at 1:45pm
John Fetter wrote:

Wes - Reversing the polarity of a battery is not new. The first lead-acid batteries were made by placing two sheets of lead in sulfuric acid, passing a charging current for a period, then reversing and passing a charging current, over and over, until the plates were formed, meaning that the positive had been covered by a layer of porous brown lead dioxide and the negative by a layer of porous lead.

Reversing a car battery destroys the essential additives that are put into the negatives to become oxidized and useless. When the battery is again reversed to the correct polarity it will suffer permanent and significant reduction in capacity due to the agglomeration of the negative particulate and due to the surface area of the negatives being reduced.

The essential additives consist primarily of lignosulfonate. Early car batteries had wooden plate separators. The wood turned out to be essential. About 70years ago battery manufacturers switched to other separator materials and their batteries began failing at an alarming rate. It took them many years to find out that they had serendipitously hit on the right material: Wood. So they created “artificial wood”, lignosulfonate and put it into the negatives.

On September 24, 2018 at 8:47am
Dave wrote:

I bought a used wheelchair with two 12V 18Ah batteries, It uses a 2A charger.  The batteries wouldn’t hold a charge. The previous owner had left the battery fully discharged for months. I replaced the batteries with the optional 12V 22Ah versions, the 22Ah batteries normally specify using a 3.5A charger. Will using the original 2A charger damage my battery or just take longer? I currently have the chair always on the charger when not in use, (the light on the charger go’s out when fully charged).  What can I do to extend the life of my batteries?

On September 25, 2018 at 11:03am
Przemyslaw Gieraltowski wrote:

you can safely use the 2A charger with the 12V/22Ah battery. The only impotrant point is watching not to overvcharge the battery ! The maximum voltage (while charging) is 14,4V ! Check if the charger is switching off the charging at that point.

On October 3, 2018 at 3:12pm
Ted C wrote:

Of course I am massively confused here. My question for everyone is this: My car is a small Nissan (Versa)which I bought used-about two years old. It has never and I do mean never the nearly ten years I have owned it, had a reliable battery. I am currently (no pun) on the third one, and the Second in just four years. I questioned a so-called battery Tech (the AAA guy) about using a float charger to prevent discharge when car is idle for a few days or like the times I have to make several stops in town and have to use a portable Jump-Start after about the third stop. His lame advice was to take it out on the highway and run it for a while every week. His smile was week when I told him of time I traveled 120 miles round trip, and the damn thing had to be jumped the very next morning!
So advice? how about hooking to a float charger when not in use? Sometimes I do not go anywhere for two or three days.

On October 4, 2018 at 12:53pm
Seb R wrote:

Hi Ted

Sounds like it could be alternator or a battery drain. Have to taken it to an Auto electrician to test? Don’t assume every mechanic shop can make sense of electrics.

On October 4, 2018 at 1:12pm
Art Schultz wrote:

If you were closer I’d fix your car problems, but I’m on an island in Alaska. I see your problems continually when working on marine electrical systems, but it’s exactly the same thing in any vehicle. There are only two possibilities. Either your battery isn’t charging correctly or there is a constant drain. The end result is the same. The battery gets run down. Since starting batteries are not designed to be deeply discharged, they go bad quickly when this happens.

A DC clamp meter would give you most or all the info you need in a few seconds. Just turn off the car and put the clamp around either the positive or negative wire. Either it will read zero, or it will read the amount of drain. Note that a DC clamp meter may show a minus sign. That’s important! The meter will indicate which direction the current is flowing. There should be a + mark on one side of the clamp. With the + mark toward the battery and the engine off, you will see the amount of drain as a positive value. Then you must go to the fuse box and pull fuses one at a time (checking each time) until the flow drops to zero.

Is the value zero with the engine off? That is the most likely scenario. Remove the clamp meter to protect it from the huge burst of current, start the engine, and put the clamp meter back as it was before. Pay attention to the + sign! Which way is the current flowing now, and how much current is flowing? The alternator could be faulty, but most of the time some connection is loose or corroded. If current is flowing into the battery (apparently normal) wait a few minutes and check again. You should see a large current that tapers off. Within about 5 minutes the starting energy is usually restored, so current becomes minimal. At that point check the voltage across the battery terminals, and also across the alternator output. If the voltage is not the same you have faulty wiring.

My last car battery worked for 8 years, and I was gone for several months at a time each year. I got an old truck last year and the quick disconnect that somebody put on the positive terminal to prevent drains in storage turned out to be faulty. Its mating surfaces had corrosion. I simply removed the disconnect. The moral here is not to go all out with add on fixes. Just fix what is actually a pretty simple problem. With a clamp meter it won’t even take 10 minutes to find it.

As soon as you have located and fixed the problem, put a new battery in. The old one is almost certainly toast.

On October 4, 2018 at 4:42pm
Przemyslaw Gieraltowski wrote:

there are many reasons which can kill your battery so often. First of all you have to use the battery with similar capacity (Ah) to the original (the first battery installed by the factory). Second - check the voltage given by the car battery charger (alternator). The battery can be loaded unsufficiently ! Third - check the “no load” current in the battery supply line. This mean the starter key is switched off and there is no current except the supply of the alarm system (by the way check if the current of your alarm system is below 50-60mA). If everything is o.k. your car should start after at least 3 weeks vacation. Fourth - carefully check if there is no temporary short in the power supply line. Fifth - check out if your battery charger is loading your battery to full capacity.Regards

On October 4, 2018 at 4:54pm
Seb R wrote:

@Art, It’s a bit more complicated than that with new car technology.

Firstly, you must wait for all modules to shut-down/enter standby. Time taken depends on make. Some are in excess of 30 minutes.
Further; all door, tailgate and bonnet catches must be in the closed position for this to happen.

If you then pull a fuse supplying to a circuit being monitored by the alarm module then you will be greeted with a greater battery drain as it/others wake up to deal with the situation. Once you return the fuse and cycle the locks you will have to wait for the shut-down procedure to happen once more.

Gone are the days when anything on cars was easy.

Smart alternators are a common thing on cars under 10 years old now. They may/may not charge during idle and for an amount of time after engine start, and will vary the charge current and voltage as they see fit. Great for misdiagnosing a poor performance alternator.

On October 5, 2018 at 11:23am
Art Schultz wrote:

It’s true that newer cars have endless energy sucking bells and whistles, and some of those things do take a while to shut down. Regardless of the vehicle, this remains a simple problem. The battery is either being drained as it sits, or it never gets fully charged when the car is running. Also note that the car mentioned is a Nissan Versa. It’s not like a Lexus, or a new mini-van with a vast array of special door sensors, etc. The Versa is going to shut down pretty quickly.

I upgrade alternators to become “smart alternators” but common automotive alternators keep getting dumber and dumber. I read through the entire product lines of almost every major manufacturer of alternators last winter—including all the option codes—and the small automotive alternators are never “smart.” In fact, the “smartest” cars actually have special alternators that can provide MORE output at idle, not less, and certainly never zero. Think of a fancy car stuck in traffic with a pair of seat heaters and a massive entertainment system. No car battery would survive more than a few weeks under those conditions if its alternator kept shutting down.

My instructions above should suffice for the battery problem as described. Your comments do remind me of a few other relevant points though. One possibility is the presence of some large power drain while the car is running. Small alternators can be overwhelmed by aftermarket gadgets. The voltage comparison between alternator and battery terminals should be done after the battery has recovered (maybe 5 minutes) but also with all the extra gadgetry running. If the voltage sags appreciably at idle from the regulator set point, and stays down, then you are overloading the alternator, which can overheat the alternator, which reduces its output, etc. The clamp ammeter will show whether the battery is draining to maintain the system at idle.

Regardless of the complexity of an electrical system, battery problems are always simple. Voltage goes up and down. Current goes back and forth. A battery only dies prematurely because its simple needs are not being met.

On November 21, 2018 at 2:51pm
Mike wrote:

I have a qustion for you guys. Ive been a mechanic of all types of equipment for many years. One day 20 years ago a guy drives up behind the gm dealership i was working at in a 55 chevy truck. I forget what he wanted but in talking he said look at this battery. Its been in my truck for 15 years. He said i dont use acid. Its 30 weight nondetergent oil. I popped the cap put my finger in it and sure enough thats what it was. He bought the battery new and dry and just put oil in it and charged it up. Not sure of cranking amps or anything but the 235 6 cyl. Spun over fine to me. I have never tried it myself. Any science on this? There was no hidden battery, just that one.

On December 7, 2018 at 11:15pm
Benjamin wrote:

Most batteries desolators in the past have proven to have numerous problems and I know there are many skeptics out there, but my company has an amazing product that does work on almost every battery.  We can reverse the sulfacation in batteries.  I can even bring most batteries back to a full 14.4V charge that you can put a load across again.  As long as the battery hasn’t fallen below 8.5V, most can be revived.  The pulse that some of the people on here talk about, yes it will over heat the battery if you apply the pulse for too long.  But ours do no such thing.  Plus ours have overcharge protection to keep from ever overcharging the battery.  Our product can extend most batteries to the 15-20 year mark.  Any we warranty them for life. And they’re not even that expensive.  Don’t say that something can’t be done unless you’ve tried everything.  And I will be glad to answer any questions on how it works.  Just email me.

On December 7, 2018 at 11:18pm
Benjamin wrote:

Look at the High Freqs from SSB Dynamic Engineering.  They are US based and warranty for life.

On December 11, 2018 at 9:16pm
Wim wrote:

Already in 1954 a patent was used to recover batteries:

https://pa0fri.home.xs4all.nl/Diversen/Laadsysteem/Reflex charging.htm

On December 21, 2018 at 5:29pm
Ellen Murdoch wrote:

In the lead dioxide potential region, i.e. over +0.95 V (vs. Hg/Hg2SO4 reference electrode), two types of processes take place on the electrode surface: processes related to the oxidation of lead to PbO2 and oxygen evolution processes. Studying the structure and phase composition of the anodic layer it has been found to comprise non-stoichiometric PbOn, a-and b-PbO2 and hydrated lead dioxide PbO(OH)2. The corrosion of lead proceeds through the following elementary reactions that take place under the action of oxygen:

Pb + O —> PbO                               (1)
PbO + (n-1)O —> PbOn                       (2)
PbOn + (2-n)O —> PbO2                       (3)

The relation between the rates of these reactions determines the type of phases formed in the anodic layer. These rates are affected by both the applied potential and the type and amount of grid alloying additives used. Thus Ag and Tl slow down considerably the corrosion rate (reaction 1), Sb accelerates this reaction, whereas Sn has almost no effect on the rate of reaction 1 but increases the rate of reaction 2, and partially that of reaction 3. As the specific electronic resistance of lead oxides depends on their stoichiometric coefficient, the changes in phase composition of the anodic layer under the action of these alloying additives affects its electroconductivity. Thus Sn and Sb increase this conductivity (Sb- or Sn- free effect).
It has been established that about 10% of the lead dioxide layer formed on a pure lead electrode comprise hydrated gel zones PbO(OH)2. On oxidation of Pb-Sb alloys the degree of hydration of the anodic layer reaches up to 30%. The hydrated (gel) zones present an elastic element in the structure of the anodic layer, which absorbs (dissipates) the mechanical stresses created as a result of corrosion and thus reduce or prevent altogether cracking of the anodic layer. This phenomenon influences the energetic performance of lead-acid battery positive plates.

Anti-sulphation devices create a ringing effect that tends to reduce the reaction rate of (1). However, the effect has marginal improvements.

This is why these devices have never been adopted on a mass scale.

On January 11, 2019 at 5:44am
Ellen Murdoch wrote:

Request for Edit in Article:

As an electro-chemist who has worked with battery electronics, please bear the following.

Ripple effects have nothing to do just with anti-sulfation devices. All electronics, including chargers, produce ripple effects. Anti-sulfation devices do not appear to cause soft shorts (in some cases that soft shorts may have occurred, the primary cause could be another factor or other factors).

Anti-sulfation devices were simply not that effective. Period. Now advanced charging algorithms already incorporate the required effectiveness needed to avoid irreversible sulfation. Innovation in such devices now rest upon the algorithm created. And these algorithms manifest in the form of a BMS a person may develop.

Therefore, what has been updated in 2016 is incorrect. Moreover, there is no such thing as a random pulse. Pulse is a well defined waveform generated based on a defined circuit. How the waveform affects an electrode is a branch of electrochemistry called voltammetry.

On January 15, 2019 at 8:29am
John Antonangeli wrote:

Can a desulfator unit be used with a float charger on a good 12V lead acid battery?

On March 8, 2019 at 3:53am
Harish KN wrote:

my 1year old inverter battery undergone a deep discharge when i didn’t used for a long time i want charge it again how much it will cost? is it too expensive?

On March 8, 2019 at 1:44pm
Janyves wrote:

@Benjamin…......... Holla at me (thorkpe@yahoo.com).