LiIon voltage at -.18V ?

[johnny13oi]

Hey guys, I have a 18650 inside of this camcorder battery pack that I am looking to repair for my dad and it appears that one of the cells inside the pack is at -.18V and the other was at about 1.8V but I charged it really slowly up to 3.7V and just left it there. I am sure the one that charged up to 3.7V could go higher but I'll do that later. I would assume that the -.18V one is dead unless there is a trick to bring it back alive. This battery camcorder is really cheap and the original capacity was only 1350mah. Do you know where I could get some really really cheap 18650s or how to bring the -.18V back to life? Oh and I tried putting a low current through the battery but nothing happens as if it was an open circuit.

Thanks

 

[SilverFox]

Hello Johnny,

When Li-Ion cells are over discharged, the electrolyte dissolves one of the electrodes. This results in reduced capacity, higher internal resistance, and electrolyte contaminated with metal particles.

When you charge the cells back up, you run the risk of micro and all out shorts developing.

I will let you decide what you want to do... If it were me, I would recycle the cells and start with fresh ones.

Tom

 

[FlashCrazy]

+1 to what Tom said. The one cell is toast. The other one may function ok for now, but it's not worth risking a possible fire down the road during use. A few bucks' savings just isn't worth it.