Can the Lead-acid Battery Compete in Modern Times?

The answer is YES. Lead-acid is the oldest rechargeable battery in existence. Invented by the French physician Gaston Planté in 1859, lead-acid was the first rechargeable battery for commercial use. 150 years later, we still have no cost-effective alternatives for cars, wheelchairs, scooters, golf carts and UPS systems. The lead-acid battery has retained a market share in applications where newer battery chemistries would either be too expensive.
Lead-acid does not lend itself to fast charging. Typical charge time is 8 to 16 hours. A periodic fully saturated charge is essential to prevent sulfation and the battery must always be stored in a charged state. Leaving the battery in a discharged condition causes sulfation and a recharge may not be possible.

Finding the ideal charge voltage limit is critical. A high voltage (above 2.40V/cell) produces good battery performance but shortens the service life due to grid corrosion on the positive plate. A low voltage limit is subject to sulfation on the negative plate. Leaving the battery on float charge for a prolonged time does not cause damage.

Lead-acid does not like deep cycling. A full discharge causes extra strain and each cycle robs the battery of some service life. This wear-down characteristic also applies to other battery chemistries in varying degrees. To prevent the battery from being stressed through repetitive deep discharge, a larger battery is recommended. Lead-acid is inexpensive but the operational costs can be higher than a nickel-based system if repetitive full cycles are required.

Depending on the depth of discharge and operating temperature, the sealed lead-acid provides 200 to 300 discharge/charge cycles. The primary reason for its relatively short cycle life is grid corrosion of the positive electrode, depletion of the active material and expansion of the positive plates. These changes are most prevalent at higher operating temperatures. Cycling does not prevent or reverse the trend.

The lead-acid battery has one of the lowest energy densities, making it unsuitable for portable devices. In addition, the performance at low temperatures is marginal. The self-discharge is about 40% per year, one of the best on rechargeable batteries. In comparison, nickel-cadmium self-discharges this amount in three months. The high lead content makes the lead-acid environmentally unfriendly.

Plate thickness

The service life of a lead-acid battery can, in part, be measured by the thickness of the positive plates. The thicker the plates, the longer the life will be. During charging and discharging, the lead on the plates gets gradually eaten away and the sediment falls to the bottom. The weight of a battery is a good indication of the lead content and the life expectancy. 

The plates of automotive starter batteries are about 0.040" (1mm) thick, while the typical golf cart battery will have plates that are between 0.07-0.11" (1.8- 2.8mm) thick. Forklift batteries may have plates that exceed 0.250" (6mm). Most industrial flooded deep-cycle batteries use lead-antimony plates. This improves the plate life but increases gassing and water loss.

Sealed lead-acid

During the mid 1970s, researchers developed a maintenance-free lead-acid battery that can operate in any position. The liquid electrolyte is gelled into moistened separators and the enclosure is sealed. Safety valves allow venting during charge, discharge and atmospheric pressure changes.

Driven by different market needs, two lead-acid systems emerged: The small sealed lead-acid (SLA), also known under the brand name of Gelcell, and the larger Valve-regulated-lead-acid (VRLA). Both batteries are similar. Engineers may argue that the word 'sealed lead-acid' is a misnomer because no rechargeable battery can be totally sealed. 

Unlike the flooded lead-acid battery, both SLA and VRLA are designed with a low over-voltage potential to prohibit the battery from reaching its gas-generating potential during charge because excess charging would cause gassing and water depletion. Consequently, these batteries can never be charged to their full potential. To reduce dry-out, sealed lead-acid batteries use lead-calcium instead of the lead-antimony.

The optimum operating temperature for the lead-acid battery is 25*C (77*F). Elevated temperature reduces longevity. As a guideline, every 8°C (15°F) rise in temperature cuts the battery life in half. A VRLA, which would last for 10 years at 25°C (77°F), would only be good for 5 years if operated at 33°C (92°F). The same battery would desist after 2½ years if kept at a constant desert temperature of 41°C (106°F).


Figure 1: Sealed lead-acid battery

The sealed lead-acid battery is rated at a 5-hour (0.2) and 20-hour (0.05C) discharge. Longer discharge times produce higher capacity readings because of lower losses. The lead-acid performs well on high load currents.

Absorbed Glass Mat Batteries (AGM)

The AGM is a newer type sealed lead-acid that uses absorbed glass mats between the plates. It is sealed, maintenance-free and the plates are rigidly mounted to withstand extensive shock and vibration. Nearly all AGM batteries are recombinant, meaning they can recombine 99% of the oxygen and hydrogen. There is almost no water is loss.

The charging voltages are the same as for other lead-acid batteries. Even under severe overcharge conditions, hydrogen emission is below the 4% specified for aircraft and enclosed spaces. The low self-discharge of 1-3% per month allows long storage before recharging. The AGM costs twice that of the flooded version of the same capacity. Because of durability, German high performance cars use AGM batteries in favor of the flooded type.

Advantages

Limitations

Comments

On October 19, 2010 at 8:58pm
ngnswamy wrote:

sir,it is very usefullfor me.nowdays,i have used ‘sla’ battery also.thank u.

On January 4, 2011 at 9:26pm
BWMichael wrote:

SLA = Sealed Lead-Acid

So many people think they are ‘dry cells’ but the truth is they still have acid inside the battery, it just cant leak because of the ‘Sealed’ part of the name.

On January 7, 2011 at 10:23am
don wrote:

My casual experience with deep cycle and starting batteries is that the deep cycle seem to have a longer life even if the deep cycle is experiencing some discharge as in the case on my boat trolling motor battery.  Furthermore, when I put deep cycle batteries in my cars it seems like they last longer than the official recommended high current starting batteries.  I wonder if the thin plates inherent in starting batteries results in them just have a shorter life?  To be fair about this, I live in Texas where it hardly ever gets cold so my vehicles just don’t need the CCA that’s needed somewhere like Minessota.

On January 7, 2011 at 5:36pm
BWMichael wrote:

Deep cycle batteries do not have high cca. But in your case where it is not cold this probably doesnt matter. Deep cycle batteries are also more expensive

On January 23, 2011 at 3:03am
Daniel wrote:

This stuff is so good. Good info.

On January 26, 2011 at 3:20am
HJ Kort wrote:

http://tinyurl.com/centurion-bilaps

BILAPS is the acronym for Bipolar Lead-Acid Power Source. In the 6th framework programme “BILAPS research project ENK6-CT-2001-00544”, supported by the European Union, CENTURION AKKU was responsible for the development of the active mass and for the assembly process.
The objective of the project was the development of a low-cost high power battery for applications in hybrid vehicles and in 42 Volt systems.

The main advantage of the bipolar battery is the high capacity it provides given its low weight. This low weight is possible thanks to the exclusion of all the lead components that do not contribute to the delivery of current. Examples include grids and cell connectors. The structure of the bipolar battery can be compared to that of a fuel cell: the stacking of cells provides the compression for the mechanical rigidity. By using only current-providing lead, weight is reduced by about 50%. This doubles the specific power (Watt per kilo)!
The advantages of a bipolar lead-acid battery compared to other technologies such as Lithium-Ion, Lithium-Polymer or Nickel-metal-hydride are:
- the relatively low price of lead,
- the proven recycling system for lead batteries (>95% for starter batteries and 100% for industrial batteries),
- low-cost production technology in mass production.

Objectives:
Specific power > 500 W/kg (power assist 30 s)
Life 400 - 600 equivalent deep cycles (12,000 - 18,000 Ah throughput for a 30 Ah system)

On February 9, 2011 at 10:16pm
Khawaja Ayaz wrote:

My name is Khawaja Ayaz. Birth date 1st May 1985. I have done Bachelor of Technology in Electrical. Wording in Pakistan Accumulators Pvt Ltd (Manufacturers of Lead Acid Battery) as a Claim Executive.
This article contains easy, effective and advance knowledge, I really like this.
U must send updates on this topic regularly via email.

Regards;
Khawaja Ayaz

On March 26, 2011 at 6:08am
Dave wrote:

Can the lead-acid battery compete in modern times? The only reason we still continue to use this technology is because it’s cheap- it’s been around for long time. most simple application that don’t require heavy power demand- car batteries, ups, will suffice with lead acid battery- anything beyond that like an EV forget it. but truth is- if you really wanted to you could get a cheap li-ion battery and it would work just as well and last way longer- i’ve seen many video’s of people using a123 for car batteries or to start a truck engine.

On March 28, 2011 at 6:24pm
Richard wrote:

Very helpful information.  Is it possible to rejuvenate a lead-acid battery that has been stored for a year and is thoroughly discharged?  There are two batteries for an electric wheelchair that are in this state.

On March 28, 2011 at 7:09pm
Khawaja Ayaz wrote:

Your organization spreading unique and advance knowledge. This Practice remain continue through mail.

Regards;
Khawaja Ayaz

On April 8, 2011 at 9:28pm
muhamad kamal hossain wrote:

I know the sulfation tank ( by lead acid proces)

On July 24, 2011 at 11:13pm
lead acid battery wrote:

I am sure lead acid battery will compete in the modern time due to its usage for over 140 years.

On August 7, 2011 at 4:18pm
bob wrote:

The lead acid battery has a recycle rate of >95%. The Lithium battery has a recycle rate of <5%. Which is environmentally unfriendly again?

On August 7, 2011 at 6:01pm
lead acid battery wrote:

LEOCH International - a lead acid battery manufacturer,

On August 9, 2011 at 2:38am
BWMichael wrote:

Sanyo eneloop batteries are 2900mah and come pre charged. They also hold 85% of their charge after being stored for 12 months. They can be recharged up to 1500 times while other brands brag about 500 cycles. I sell and recommend them to everyone, and I use them myself for everything

On September 15, 2011 at 4:39pm
NanooGeek wrote:

Several UB5-6S, used in squared-off flashlights w/ halogen bulbs, suddenly failed. They seemed to charge to nearly 6V, but drop to 0.2V when the small bulbs are switched on. With two of them, leaving them upside down in the flishlights may have been a problem. However a 3rd was upright in a closet, still over 4V, and exhibits the same problem.

On October 3, 2011 at 7:43pm
Khawaja Ayaz wrote:

In this site some valuable information is missing, i want to share with all of you.
This information is about First true functional battery invented.
n 1800, Alessandro Volta of Italy built the voltaic pile and discovered the first practical method of generating electricity. Count Volta also made discoveries in electrostatics, meteorology and pneumatics. His most famous invention, however, is the first battery.
Alessandro Volta - Voltaic Pile
In 1800 Volta invented the first true battery which came to be known as the Voltaic Pile. The Voltaic Pile consisted of pairs of copper and zinc discs piled on top of each other, separated by a layer of cloth or cardboard soaked in brine (i.e. the electrolyte). Constructed of alternating discs of zinc and copper, with pieces of cardboard soaked in brine between the metals, the voltaic pile produced electrical current. The metallic conducting arc was used to carry the electricity over a greater distance. Alessandro Volta’s voltaic pile was the first battery that produced a reliable, steady current of electricity.

History of Battery Development
1600 Gilbert (England)      Establishment electrochemistry study
1791 Galvani (Italy)        Discovery of ‘animal electricity’
1800 Volta (Italy)            Invention of the voltaic cell
1802 Cruickshank (England)  First electric battery capable of mass production
1820 Ampère (France)        Electricity through magnetism
1833 Faraday (England)      Announcement of Faraday’s Law
1836 Daniell (England)      Invention of the Daniell cell
1859 Planté (France)      Invention of the lead acid battery
1868 Leclanché (France)      Invention of the Leclanché cell
1888 Gassner (USA)      Completion of the dry cell
1899 Jungner (Sweden)      Invention of the nickel-cadmium battery
1901 Edison (USA)            Invention of the nickel-iron battery
1932 Shlecht & Ackermann (Germany)  Invention of the sintered pole plate
1947 Neumann (France)      Successfully sealing the nickel-cadmium battery
Mid 1960 Union Carbide (USA)  Development of primary alkaline battery
Mid 1970                         Development of valve regulated lead acid battery
1990                         Commercialization nickel-metal hydride battery
1992 Kordesch (Canada)  Commercialization reusable alkaline battery
1999                         Commercialization lithium-ion polymer
2001   Anticipated volume production of proton exchange membrane fuel cell

On November 24, 2011 at 4:59am
sutaryo wrote:

specification of Iron & Chlorine content on the battery separator glassmat

On November 25, 2011 at 4:47pm
NanooGeek wrote:

“A better battery for start-stop”, 26Sep11: www.sae.org/mags/aei/10199

On March 9, 2012 at 12:36am
mahesh kumar wrote:

super

On July 30, 2012 at 8:19pm
Jason wrote:

We are a Chinise Sealed Lead Acid Battery supplier, I think SLA is more reliable.

On September 14, 2012 at 5:01am
SUNIL wrote:

PL SEND US TECHNICAL KNOW HOW TO MAKE GOOD QUALITY SLA BATTERY

On December 21, 2012 at 2:57am
Malcolm wrote:

Is there a method to “repair” a sulfated SLA?  I neglected to keep a 4V charged and now won’t recharge.

On February 16, 2013 at 3:00am
s ganeshkumar wrote:

Dear sir
we are looking for high performance plante
qty = 2 set

with regards
s ganesh

On February 22, 2013 at 1:43am
manuka wrote:

12V 7Ah SLA batteries are a global standard for applications where weight is incidental. They’re often hence used in standby power systems (UPS/security etc) & mission critical setups may replace them well before they fail. I’ve used such “discarded” ones for decades to great effect in less demanding applicationns (educational especially), and often get another 5 - 8 years out of them.

The rise of cheap “backyard” solar PV, with LED lighting & cell phone charging in mind, has continued to make them perhaps the best energy store for tight budget applications.

On March 26, 2013 at 1:10pm
m kumar wrote:

This is a very informative.Your doing a wonderful job.Keep it up.I would love to stay in touch with this site. Also I wanted to know the differences between a Lead acid battery (plante)  & Nickel Cadmium battery. which is better taking into consideration all technological ,economical & enviormental aspects?

On April 2, 2013 at 8:15pm
michael curry wrote:

I REQUIRE 2 BATTERIES SIMILAR TO PORTALAC RECHARGEABLE LEAD-ACID 12V-17AH——PE12V17   CAN YOU HELP, PLEASE. REGARDS, MICHAEL.

On April 30, 2013 at 1:06am
Alfred wrote:

Is the battery suitable on my dvd player

On May 18, 2013 at 7:43am
angela wrote:

how bout refurbishing a 24 volt 10 amp sla electric bike battery? i cant afford to keep buying them and some guy said he took it and got it fixed for fifty bucks..others swear its sealed…not completely i hear

On July 2, 2013 at 9:39am
Brian Z wrote:

Can anyone provide a reliable source that states how much the average percentage weight of sulfuric acid is in lead-based battery?  Need to solve for total weight equations for SARA Title III reporting purposes and was hoping for a quick calculation.  Thanks.

On July 2, 2013 at 10:45am
Manuka wrote:

I must have had a sheltered life here in NZ, as your SARA (Superfund Amendments and Reauthorization Act) needed Googling.  See more at: http://www.msdsonline.com/resources/regulatory-information/sara-reporting.aspx#sthash.e2xpLLrs.dpufmention  
A simple check would be to simply weigh a weary car battery, then weigh again after draining it’s suphuric acid. However there are MANY types of lead acid battery - specify at least if yours are classic wet or gel types.

On August 3, 2013 at 5:32pm
Paul Lowe wrote:

I have an old honda 6volt bike that the battery is not available in Australia.

I would like to replace with sla or other.  Existing is a 11ah type and powers a small starters motor (motor is only 50cc). Concerned about charge rates etc.

Any suggestions as to be choice!

Paul

On August 3, 2013 at 11:47pm
Manuka wrote:

Sure- lots of suggestions, but first please specify the battery bay dimensions!  The existing 6V 11Ah ( wet cell ?) may be “block of cheese” sized, which implies you at least have some room to play with.

On September 20, 2013 at 3:49pm
Scott wrote:

there is quite a bit of disinformation given here. For example, the energy density example is way out of line. Lead acid batteries have the HIGHEST energy density per cell bar none. they are NOT self destructive (explosive) such as other types of rechargeable batteries that are available. And as another poster commented, they supply the highest level of recyclability of all rechargeable. Combine this with PROPER recharging methods, and size selection they can offer near indefinite capacity for a given use. The MODERN automotive battery is actually a step backwards in longevity, due to the use of thinner plates and construction techniques to increase profitability, at the cost of plates that rapidly warp with regular charging, reducing the cells capacity, as opposed to the heavier plates used in the older batteries which were known to last easily two to three times their rated life span,  Golf cart and forklift batteries use heavier plates, though not as heavy as the older automotive batteries, and are valued for their ability to last for much longer as a result are valued in solar power systems.  Having worked in the design of these batteries and their applications in backup power systems. I find it a bit disturbing that all this article supplies was support for popular myth and not much more.

On September 20, 2013 at 4:57pm
Manuka wrote:

Well said Scott- the almost laughably small Pb-Acid batteries in modern cars immediately say “short life”  to me!

Aside from Pb-Acid weight issues (which may tend incidental for static applications) I’ve got to say that lead toxicity is increasingly likely to condemn them. Lead may well be recycled but environmental & worker health issues arising are NOT trivial. Here in nearby Petone (Welllington, NZ) we’ve just had a large battery (re)processing factory closed for this very reason. Lead emissions from it have been an issue for years, and the firm (Chloride) found meeting modern standards too difficult & costly…

FWIW -since last I commented seductively lightweight & high cell EMF (3.6-3.7V) rechargeable Lithium batteries have become increasingly appealing. Lithiums certainly look the way ahead, & their use in e-cars/e-bikes is growing rapidly. Experience shows Li-ion & Li-Po types are almost too powerful for their own good (Dreamliner woes…), & their cycle life may be only a few 100 times. I’ve however done significant work with the far safer &  longer cycle life (~1000s) 3.2V LiFePO4 ( “LFE”) versions & have become a great fan of them. Stan.

On September 30, 2013 at 8:09am
Scott wrote:

Stan, the amusingly named LiFePO4 looks like it will be the battery of the future. it has the “Life” needed for a reasonable capacity, ad as soon as cost can be brought down, we will be seeing more development being done with it as a true storage cell.
You mentioned the toxicity issues with the recycling of lead acid batteries. This is another thing I have issue with, these modern “almost a battery” light weight designs quite literally create the toxic issue you mention by the sheer nature of the rapid breakdown of these thin plates batteries. the old design, with heavier plates kept the batteries in service much longer,  and presented much less of an environmental hazard as a result. the sad part is the biggest issue with recycling these batteries is the case design itself. Had the manufacturers sat down and designed a case with a removable top.. that was sealed with a silicone adhesive, just like a windshield (wind screen) and had removable caps on the individual cells to allow water replenishment, and electrolyte removal, the battery could literally be 100% serviceable and recyclable, just like a starter or alternator, and the lead reprocessing and acid recovery, could be handled in an entirely enclosed environment under robotic process control, in the same manner that the lead is refined here in the states. the battery cases would be able to be reused or remade as necessary with minimal waste in the entire process.
Seeing as I live roughly at the 44th parallel north (44 degrees 51 minutes)  I deal with the effects of the winter cold on batteries every year. These thin plate lead acids do not impress in the least, a battery rated at 550 cold cranking amps (CCA) is good for that rating for less than one season and loses about 25-30% of it’s rated capacity every season there after. and IF the battery goes dead and the electrolyte freezes it will bend the plates and either short one or more cells out or break the circuit leaving you with a completely dead battery, if the case didn’t crack open. Looking back to the heavy plates in the old batteries, this simply didn’t happen, the plates were too heavy for the iced electrolyte to bend, and the case too heavy to breach, so the worse that happened is the need to deep charge it with a 2 amp charge for 24-48 hours to bring it back, AFTER it was thawed out. 
Back to the LiFe cells, I’m a ham radio operator, and I make extensive use of them. easy to charge, extremely low self discharge rate, high current source… I have them in all of the family’s hand held’s (the whole crew is licensed) as well as in the portable power supply for my qrp rig. It’s amazing what you learn out of necessity. And the good people you meet world wide.  Take care, an hope to talk to you again!

On October 1, 2013 at 10:01pm
Manuka wrote:

Good points- I’m at latitude 41 Sth, but only a stones throw from the sea seven winter frosts are rare. By chance our Y2k Toyota Echo recently needed a new battery - the existing factory fitted one has lasted 13 years!

I’m also a ham (ZL2APS since 1967!) & increasingly find LiFePO4 ideal for all manner of household items. Canon digiral cameras that are picky onAA NiMH especially seem to thrive on LFE (& of course a few dummy cells!).    Stan.

On February 11, 2014 at 2:44am
katie wrote:

can anyone help me with the Temperature compensation in Gassing Voltage of AGM VRLA battery?. Pls..

On March 10, 2014 at 5:39am
mick.mick wrote:

ANY COMMENTS ABOUT NICKEL IRON CELLS…THE FUTURE FROM THE PAST ????

On May 28, 2014 at 11:08am
Rui Pedro Silva wrote:

Dear all, I´m developing a new kind of battery using a new kind of Lead free technology. In order to know if “my battery”  is competitive with Lead-Acid batteries I need to know what are the cost of Lead Acid batteries production. Does any one know where I can find this information or can you give me a contact of a Lead-acid battery expert?
It would be very help full.
Thank you all very much.
Email me: ruipedrots@gmail.com

On May 31, 2014 at 9:42am
Mark Wendman wrote:

some corrections ( from innovation ) re
RE > Lead-acid does not lend itself to fast charging. Typical charge time is 8 to 16 hours.

> Firefly’s OASIS 3D 12v 110amphr Group 31, is capable of 250amp (re)charging currents. This is done all the time in manufacturing final test, and the battery barely warms. Reason for the performance gain in fast charging is the ceramic carbon foam negative electrode plate is both a hugely better electrical conductor than common lead grids, and also is a superb thermal conductor / heat sink, far better than the negative lead grid replaced from std conventional lead acid batteries.

> Also the negative electrode has much larger active surface area of the lead oxide due to roughening of the lead oxide by the supporting carbon foam substructure.

> So a single Firefly OASIS 3D group 31 can with proper electronics ( high power charger ) be easily and safely recharged in 30 minutes to 80% of charge capacity. Beyond 80% SOC, charging should be slowed due to monotonic increase in energy loss from water electrolysis onset ( from bubbles shading the active lead oxide area, and energy dissipated in the electrolysis itself ).

> For safe fast charging of string battery packs, we recommend specialized BMS systems monitor each battery during string charging, to avert unsafe conditions in more
complex pack topology ( wiring /  series circuits ) with charger interlocks. The BMS needs to interlock the charger as hints of unsafe thermal runaway conditions might occur ( rarely ) in a battery fault. Most BMS’s are not configured for this type of fast rate charging safety monitoring of all batteries in a string, but this can be readily designed by competent electrical engineers, to handle fast charging of Firefly lead acid strings safely, akin to what is done in sophisticated Lithium Ion chargers, adapted for electrical characteristics of carbon foam lead acid batteries ( of Firefly )

RE >
A periodic fully saturated charge is essential to prevent sulfation and the battery must always be stored in a charged state.

> For Firefly’s Carbon Foam Lead Acid, the battery can typically recover easily from 6 months storage at zero state of charge, In 5 charge discharge cycles, typically 90% of data sheet capacity is restored, and continues to increase asymptotically.

> Notably in most all cases that might brick / kill conventional lead acid batteries, Firefly’s sub millimeter sulfation particle structure ( versus common lead acid Film type sulfation ) is easily reversible by simple common charging cycle.

> Since Firefly’s self discharge is low 2%/month, you’d possibly wait 5 years until the Firefly lead acid is fully self discharged from shelf storage. Not recommended, but simple seasonal storage is easily recoverable with Firefly’s Carbon Foam Lead Acid battery technology

RE > Leaving the battery in a discharged condition causes sulfation and a recharge may not be possible.

> obviously this is not the case with Firefly’s carbon Foam Lead Acid batteries. Sulfation will occur, but in near all instances of modest duration discharged condition, Firefly easily recovers, due to the tiny particle (freckle like ).sulfation that forms in Firefly.

> As a general point here, innovation in lead acid does occur, and can contradict facts of old common lead acid. Firefly is indeed very different, and far better than recent “smart carbon” efforts. On many metrics, not merely just a few discussed here yet.

On May 31, 2014 at 9:56am
Mark Wendman wrote:

RE >
Depending on the depth of discharge and operating temperature, the sealed lead-acid provides 200 to 300 discharge/charge cycles. The primary reason for its relatively short cycle life is grid corrosion of the positive electrode, depletion of the active material and expansion of the positive plates. These changes are most prevalent at higher operating temperatures. Cycling does not prevent or reverse the trend.

> Firefly’s carbon foam lead acid battery has a proven 1200 deep discharge (80% DoD) result in the lab and a 1000 deep discharge rating. At 50% DoD common chemistry calculations indicate approx 3500 cycles are likely and at 20% DoD approximately 10000 cycles are likely.

> The battery architecture of Firefly’s Carbon Foam lead Acid battery strongly inhibits corrosion of the positive lead grid and inhibits damage / shedding of the positive active lead oxide which is the common weakness of standard lead oxide batteries.

> The reason for this durability improvement is electrochemical competition between the standard Positive electrode in the Firefly and the far larger electrochemical surface area of the lead oxide deposited on Firefly’s Carbon Foam negative electrode plate. Most sulfation occurs on the Firefly negative Carbon foam electrode, and of tiny particles easily reversible by simple charging.

On June 21, 2014 at 3:38am
Hari Narayan wrote:
On September 2, 2014 at 9:29pm
Rahul Rajbhar wrote:

I want to make a single 2 volt cell of lead acid battery. What must be the

(1)  Thickness and area of Lead and Lead oxide plates.
(2)  The distance b/w the plates.
(3)  Height of separation of cell from bottom of the battery.
(4)  is any separater required b/w plates? If yes, then what type of material and area.