Is it safe? Dead cell come back

adergotardo

Member
Hello, everyone.
I got a Zippy Battery, 25c 2200mAH, 3Cell. One of the cells are vitually dead (3,69V; 4,20V and 0,26V). So I found this video (in Portuguese, because I'm a Brazilian) where a guy teach to recover a dead cell using other battery. He put those together and let the cells balance itself. I wonder if it is safe and if will work on my dead battery.
 

xuzme720

Dedicated foam bender
Mentor
Why is your one cell dead? That in itself might be cause for alarm...

If it were my pack, I would make it a 2S and get rid of the dead cell. But that is not the safe route I'd recommend for beginners.
 

adergotardo

Member
I think my battery died because a crash. Somehow, there is two little hole in one cell. Someone told me to do that, make it a 2 s battery. But I assume it's dangerous.
 

jhitesma

Some guy in the desert
Mentor
Charging a lipo that's gone that low is dangerous. Doesn't matter if it's charged from a charger or charged off another battery, In fact charging with a real charger is probably less dangerous than this because with this there's no current limiting.

I've heard plenty of tales of people bringing dead lipos back to life - but it should only be attempted if you're well familiar with the risks and dangers of doing so and take appropriate precautions.

If your cell is dead due to holes in the pouch...then it's dead and not coming back no matter what. Trying to charge it is just asking for a fire at that point.

If you're not comfortable enough to remove a cell and turn it into a 2 cell pack then I'd say you're not equipped to try force charging it back to life like this either (though in this case with holes in the pack even if you were equipped I'd suggest not even trying.)
 

xuzme720

Dedicated foam bender
Mentor
I'd have to agree. Holes in the cell are not good and nothing you can try will bring that one back. Changing a 3S to a 2S isn't difficult, but it does have a high potential for bad things like shorting and fire if done incorrectly. Best thing I can tell you is to google lipo construction and see if you understand how the packs are wired. Understanding that is paramount knowledge to have before attempting any lipo surgery.
I would normally give a step by step for most procedures but frankly, I can't in this case. If done incorrectly, there is almost a guarantee of fire due to shorting or polarity reversal. So if you can find enough info to understand EXACTLY how the packs are wired, you will already know how to convert the bad pack.
Does that make sense?