my AA batteries short circuited, ruined?


by Jarfi
Tags: batteries, circuited, ruined
Jarfi
Jarfi is offline
#1
Dec5-13, 03:15 PM
P: 264
I had 4 1.2 volt guys lying around in a holder. The 2 wires sticking out were lying around and I started smelling stuff. I look down and I see they are connected together and the steel points seem to be slightly melting together, the batteries were hot, did it damage them or is this okay?
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davenn
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#2
Dec5-13, 11:04 PM
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its probably damaged them
ie. they have probably gone flat or close to it

you need to be more careful with batteries and wires like that
its how fires can start


Dave
Jarfi
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#3
Dec6-13, 12:18 PM
P: 264
Quote Quote by davenn View Post
its probably damaged them
ie. they have probably gone flat or close to it

you need to be more careful with batteries and wires like that
its how fires can start


Dave
Yep, obviously they went flat. I wouldnt really care if they were normal AA batteries, I'd just buy new ones. BUT those are high grade rechargable batteries, so I can always charge them again.

I was simply wondering if it had damaged or lessened the maximum capacity by going over some sort of heat tolerance limit, maybe the heat started some chemical changes that may have damaged the capacity. That was simply what I was wondering about. Buying 4 rechargable batteries is kind of expensive for a student like me.

AlephZero
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#4
Dec6-13, 02:06 PM
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my AA batteries short circuited, ruined?


The batteries will have a pressure relief system to reduce the risk of them exploding if they overheat. That should re-seal itself when they cool down, but you lose some of the contents of the electrolyte, e.g. water that is boiled off as steam. That will permanently reduce the charge capacity of the batteries, and increase the internal resistance, so they maximum current they can deliver is reduced and they will get hotter at normal charging and discharging rates.

If the battery cases are not obviously distorted, I would try recharging them before you throw them away. But don't use them for anything critical in case they start to leak, or they self-discharge faster than they are supposed to.
Jarfi
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#5
Dec11-13, 11:58 AM
P: 264
Quote Quote by AlephZero View Post
The batteries will have a pressure relief system to reduce the risk of them exploding if they overheat. That should re-seal itself when they cool down, but you lose some of the contents of the electrolyte, e.g. water that is boiled off as steam. That will permanently reduce the charge capacity of the batteries, and increase the internal resistance, so they maximum current they can deliver is reduced and they will get hotter at normal charging and discharging rates.

If the battery cases are not obviously distorted, I would try recharging them before you throw them away. But don't use them for anything critical in case they start to leak, or they self-discharge faster than they are supposed to.
UPdate. I have tried recharging them and am now waiting to see what happens, I tried them before that and there was no charge left. Now they are getting scarily hot, not sure if they did before but I think it's probably a bad sign.
RocketSci5KN
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#6
Dec11-13, 05:25 PM
P: 157
Any time any battery gets too hot while charging is the time to disconnect and throw them in the battery recycling bin after they cool down. They have an internal short which makes them worthless.
mnshahid
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#7
Dec14-13, 06:19 AM
P: 7
Hi
I have a fisher price baby swing. It has 4 1.5v batteries of size D. I tried to convert it to a 6v DC charger but that didn't work. The charger specification is output=400mA 2.4VA. If someone can help me please to find a right charger as this doesn't work correctly and swing does not swing as swings with the batteries. Swing becomes more noisy and does not swing.
RocketSci5KN
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#8
Dec18-13, 06:11 PM
P: 157
Looks like a D-cell can do about 1A max, so your 6V charger should be able to do this also. Going to 1.5A or 2.0A would not hurt if that's what you have.

http://www.candlepowerforums.com/vb/...r-D-alkaline-s

Obviously, if you modify the power system, you must remove the batteries and wire up only the charger where the batteries used to be (+) to (+) and (-) to (-). This charger must not be used to charge any batteries.


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