Fried battery

[Steve Hill 5]

I have short circuited my Li-po battery(red to black; in my defence she was very good looking). a) can it be saved and b) if it can’t be saved, what is the best way to dispose of it?

[Dave Hess]

If it still works, it'll be OK. If it doesn't, it probably means that one of the inter-cell conne tions has vaporised. You can sometimes repair them by pealing off all the outside layers to expose them, then solder some thick copper wire across what's left.

You can sometimes do creative things, like convert a 4S into a 3S and 1s or two 2Ss.

[gangster]

I agree with Dave

[Jon H]

While i am sure its possible i am not convinced that recommending lipo's be dismantled is a good idea. If something went wrong or the cell was shorted again during the procedure you could easily end up with a bonfire on the bench. Even if everything went well the cell might still be damaged and will give up during the next charge.

Personally i would bin any lipo that gave me cause for concern. if memory serves chucking them in a bucket of salty water over night discharges them to nothing. They can then be taken to the dump or wherever else your local battery collection point is.

[John Lee]

Posted by Jon - Laser Engines on 22/01/2019 13:37:40:

if memory serves chucking them in a bucket of salty water over night discharges them to nothing. They can then be taken to the dump or wherever else your local battery collection point is.

No!

From the BMFA Battery Safety Booklet:

One thing that must be stated is that the widespread suggestion that disposal should be preceded by degradation in a bucket of salt water is not now recommended. This process adds Lithium salts to the water, and the disposal of this through our normal drainage systems is likely to affect the work of our Water Authorities, who use Lithium as a trace element when locating leaks. At the time of writing, the best available disposal procedure is via the local authority Environment and Waste department......

Steve I'd suggest that you have a proper read of the booklet available here.

[Jon H]

Posted by John Lee on 22/01/2019 13:48:44:

Posted by Jon - Laser Engines on 22/01/2019 13:37:40:

if memory serves chucking them in a bucket of salty water over night discharges them to nothing. They can then be taken to the dump or wherever else your local battery collection point is.

No!

From the BMFA Battery Safety Booklet:

One thing that must be stated is that the widespread suggestion that disposal should be preceded by degradation in a bucket of salt water is not now recommended. This process adds Lithium salts to the water, and the disposal of this through our normal drainage systems is likely to affect the work of our Water Authorities, who use Lithium as a trace element when locating leaks. At the time of writing, the best available disposal procedure is via the local authority Environment and Waste department......

Steve I'd suggest that you have a proper read of the booklet available here.

Thanks for the update John. Its been a while since i checked up on lipo disposal and at the time salt water was the recommended treatment.

[Robin Etherton]

Did you get a picture of her?

[Don Fry]

I assume, when distracted by lust, that you momentary touched the contacts, the earth moved, and you jerked them apart. If so, no damage to the battery.

You will be told you can discharge an old battery by running it flat through a resistance. I.e. A suitable car bulb, to 3s, 2 bulbs in series to 6s. The bloke at the disposal facility will tell you they don't care, charged or not, the bin is designed to deal with mishaps.

[Steve Hill 5]

Unfortunately, Don, electricity moves a lot faster than my hands. The battery will neither charge nor discharge on my charger, which gives a “ cell or connection” error message. Having read the booklet and been suitably chastened ( thank you John) I will be disposing of the battery as recommended. Thank you to all who have replied.

[Don Fry]

Ah well, at least your eyes work.

[Dave Hess]

If you can solder, repair isn't too difficult. As I said above, the strips that join the cells act as fuses abd vaporise when you short the battery. Any sensible DIY person should be able to repair one as long as there's enough of the tab left to solder to. I've repaired several batteries like that. It's no more difficult than soldering a connector to a lipo, which some of us do to nearly every pack.

I used to use lipos for electric bikes up to 16S, and when connecting the harnesses, it was easy to get an accidental short, which normally resulted in the problem you have.There's very little chance of fire. If you do short anything, the contact area gets vaporised so immediately disconnect it.

Obviously, ham-fisted persons or dunderheads should leave well alone.