Sharing Battery Knowledge
People want easy-to-read battery information. To share knowledge, I condensed the material from “Batteries in a Portable World,” a book I wrote, into essays and created www.BatteryUniversity.com. The website went on the air in 2003 and quickly became a popular resource of battery information worldwide. New material is being added as it becomes available.
Much of my writing comes from my personal experience working with batteries. I also draw on test results from our own laboratories at Cadex. While laboratory analyses have their rightful place, I respect the opinions of battery users, especially the feedback from BatteryUniversity.com. This interface with the user gives me an advantage in learning how the battery behaves in the field. Such information is, in my opinion, more important than regurgitating reams of laboratory tests. The critical mass speaks louder than fancy brochures and printed specifications.
There is no black and white in the battery field, only many shades of gray. The battery behaves much like us folks — it’s a black box with a mind and mood of its own; it’s mystical and unexplainable. For some users, the battery causes no problems at all; for others it’s nothing but a problem.
When looking at a battery we must keep in mind that it is electrochemical. It’s a vessel that is slow to fill, holds relatively little storage capacity and has a defined life span. Although critical improvements have been made over the years, the progress is marginal compared with the vast advancements in microelectronics. As long as the battery relies on an electrochemical process, limitations will prevail.
As there is no perfect spouses or ideal employees, so also have batteries strengths and limitations. The manufacturer has the choices of building a battery for long runtimes and low cost, but this pack will have a limited service life. Another variety is high load capabilities but this pack will be bulky. A third group offers extended life but the battery is heavy and expensive.
Manufacturers of electronic devices base the performance on a perfect battery, a condition that only exists when the battery is new. Runtime, low cost and safety have been the number one criteria, and in consumer products longevity is often neglected. With the electric vehicle, this emphasis is changing, a move that will benefit the battery industry immensely. Meanwhile, there are ways to prolong batteries and BatteryUniversity.com will assist.
BatteryUniversity.com is written for the professional user who needs a basic understanding of battery behavior. It also served the ordinary user who wants to get the more life out of a pack. The website stresses the strengths and limitations of the battery, explains different battery types and provides useful hints in choosing a battery. The website is easy and entertaining to read and makes minimal use of technical jargon. BatteryUniversity.com addresses only commercially available batteries and only mentions new developments in passing. Since my background is electrical, I tackle batteries from the electrical side and less on chemical reaction.
Comments
Just look up the author of the book he mentions which he wrote. Hah, duh.
i want to ask u in lead acid battery (+v plate) what is the that matereial with the help of this plate make oxaid
For mohammed javeed, for testing the material, give the material to a material testing laboratory for a complete report.
My Laptop current rating is 1.5 ampere at 240 Volts AC ,how many laptops can I charge simultaneously with a power points rated 240 volts AC,13 amperes?
i have a battery pack of 18 volts ni-cad and 18 volts lithium batteries, my battery charger is for ni-cad battery pack, can i use my ni-cad charger for my lithium battery pack?
No you cannot. Li-Ion batteries require specialized chargers to avoid damaging the battery.
Nice concerning as better as clarifying position.Gives Thanks for providing for us.I show your article with my delight.
thanks a lot for sharing the helpful information.
can you use a lithium-ion with a regular power tool that used older batteries? I have dewalt power tools..
For kamal, for testing the material, give the material to a material testing laboratory for a complete report.
I want to procedure manuals for Battery production
For Julie, the answer to your question is usually no, because Li-Ion requires a specialized charger, If you can make a Li-Ion pack fit a Ni-Cad tool, then it is possible, but again you cannot use the NI-cad charger.
What might be the cause of a VRLA battery swellin g and bursting its case? We have two of them in a 24v battery back up system. Float volatge is maintained at 27volts by a specially designed battery supply so i do not think that it is overcharging.
Sounds like the valve failed. When pressure rises, the “Valve Regulated Lead Acid” battery is supposed to vent that pressure.
If it can’t vent through the valve designed for that purpose, it will vent another way.
Boom.
very nice imformation…about battery technology as a manifacturer of batteries in india.. its very good to read all about batteries…..appricated…
#corrections
‘filed’ should be ‘field’.
thanks Paul for the info.
spelling….. “field”
“This interface with the user gives me an advantage in learning how the battery behaves in the filed.”
Thanks Anthony, we have made the correction.
I have observed many problems with voltage depresion in NiMH batteries usen in defibrilators. This is usualy corrected with cycling. Recently the impedence has also become a important value to look at on these batteries as well as the ones with higher impedence are not performing adquately even though the total capacity of the battery is still over 100%
I want to produce UPS batteries.
Can anyne help me?
Vietnam seems to be the new place to start producing UPS batteries.
i want to ask,,,,can a rice cooker be power by using battery power,,,,,if can,,,,what the best battery for it.small battery to make portuble rice cooker
While electrical energy is efficent for powering moters and electricial circuits, there are a lot of better ways to generate heat. Battery powered heaters are not a good idea.
I’m looking for the most basic first principle explanation of how a battery works. Why do differnet metals like copper and zinc have different potentials and can they be calculated from their atomic structure.
i really want to know what is the difference between old batteries and new batteries?,please help me =) btw thanks for the answer
Batteries are parishiable items, while they do not go bas as fast fruit, whould you want old fruit or fresh fruit? Refrigiration helps extend the shelf life of batteries as well as fruit.
Just as different fruits go bad at different rates. different battery types go bad on the shelf at different rates as well. NiMH batteries seem to go bad in a few years, SLA batteries should last 5 or more years, as long as charge them at least once a year. Primary lithum batteries may last 10 or more years, rechargeable lithiums should last 5 or more years with about 1/2 a charge maintained (most are the smart type and that smart logic draws power so it helps to charge them some every three to six months.. Nicad batteries will sit just fine discharged, for 10 or more years, but will require a long trickle charge to wake them up after sleaping more than 3 months.
The problem: a small drive, do not rich to 43V.We want to get your help on Battery 36V 10Ah,and in general to understand the operation of the battery.Here are the following story:
We got a battery that travel distance, less than 20 k’m.We opened the battery and we find the following cell data in Vallts:3.368\3.71\3.46\3.71\3.296\3.75 - 3.349\3.36\3.35\3.35\3.69\3.45
We took the battery and emptied it, and we measured again and found that one cell was 2.5 volts.We replaced the cell.Then we charge the battery to “full” , we measured the battery and it show 40.6V.the following cell date:3.328\3.334\3.314\3.482\3.326\ - 3.321\3.335\3.317\3.319\3.339\3.332All cells look OK , but the battrey to not rich to 43V. Why the battrey does not rich to 43V? why the charge stop at 40.6V?Is it the BMS?Can we get instructions for testing ,so we can see if BMS or one of the cell is not work?
I finally find this perfect website about batteries.
I’m doing some test about LiFePO4 batteries, e.g. self-discharge rate test.
I usually charge and discharge the cells completely. Then charge the cells to some capacity. After that, put them in 60°C for 7 days. Then discharge them to test the capacity.
I’m wondering if there is a standards for me to do the test or it’s just everyone has his way.
Thanks for sharing.
I do not know of a standard for this type of test, however what ever info you could shair from your tests would be of interest.
I usualy compair the loss in 24 hours after a full charge to the loss after a week or so, to try to deturman how much is loss of over charge vs normal self discharge.
sense you are not fully charging, there should be no over charge.
I was told that the high temp. aging test is the most common used way to test self-discharge rate in China. I used to compare the charged capacity read from the battery tester to the discharged capacity after 7 days in high temp. tank. But recently, my data is totally different from what the supplier gives us, even though our methods are totally the same. And the engineer said that they use the real capacity of the cell to compare with the discharged capacity. I don’t think it makes sense since the cell is not fully charged. So I began to search what is the right way to test the self-discharge rate of a cell. I’m confused about which data should I use to do the calculation.
please tell me about battr
hello. i m battery manufacture in india. made rv battery.(automotive battery)i plan makeing marein battery. if u know how work marein batt. plat size thiknes. plat size standerd. deep cycle?sugess me. thanks for read msg
Hi David, just found your site wow thanks, Question what damage if any will a li-ion polymer charger do to a li-ion phosphate cell.
I want know that “how make the active material"pleas help me.
Dear May,
I am Tahir from Karachi , Pakistan and i am working in lead acid battery company.
i had been tested many batteries, self discharge test (another name Retention of charge test ) in our lab. Self discharge means the loss of useful capacity of a battery on storage due to internal chemical action its called local action.
TEST METHOD
(1) Battery shell be fully charge.
(2) Check battery capacity (5hrs or 20 hrs) its called—-C1
(3) The battery shall be store for a period of 28 days
(4) Check battery capacity in same condition, its called—-C2
FORMULA
Self discharge test (%) = Loss of capacity (C1-C2) / C1 x 100
Note : Percent shell be not more than 20%
(It is PSI Standard)
Best wishes,
Tahir
(syedhussain123456@hotmail.com)
Hello,
I have a question that I have assumbled a battery in which I used 5 positive plates (new) and 6 negatives plates(used) per cell. I tried to test my battery but the problem is that each cell gives me 2.3v and total of 6 cell provide me around 13.8v and I tried my inverter and tried to start a fan and 2 savers and checked the voltage which was 13.4v but my fan and saver just fluctuate and don’t work at all. Can you guys please let me know what could be the probelm.
I have checked there’s no problem with terminals. I am still using my inverter on another battery and inverter works fine there.
Thanks in advanced.
Abdul Jabbar
what is the name of the person who made sharing knowledge of the battery article my science project is due tommorow and i need the name of the author