Over drained battery question

[Gallant]

Low voltage cut off failed in a mod with a single 18650 Samsung 30Q battery led to over draining the battery down to 0.86 volts. In a nitcore external charger I managed to recharge the battery back to 4.2 volts. Can this battery still be safely used?

 

[greek mule]

Quick answer,NO.
"When a li-ion battery drops bellow 2,0 V or so, the chopper electrode inside of it literally starts to dissolve.
When the battery is recharged this dissolved metal is plated back onto parts of battery that should not be conductive.This can cause an internal short-cirquit which can lead to overheating,venting,or even bursting of the battery."
Source:Baditude's blog.

 

[Baditude]

• Is it safe to use a charger's "recovery" feature to bring back an overdischarged battery?

 

[greek mule]

Quick answer,NO.
When a li-ion battery drops bellow 2,0 V or so, the chopper electrode inside of it literally starts to dissolve.
When the battery is recharged this dissolved metal is plated back onto parts of battery that should not be conductive.This can cause an internal short-cirquit which can lead to overheating,venting,or even bursting of the battery.

@Baditude I had this text copied a long time ago and I didn't remembered it's source, that is from your Blog.

 

[sonicbomb]

0.86 volts, definitely recycle that battery

 

[DaveP]

If in doubt, throw it out. I agree with the above posts. Once it's drained below 2.5v wrap it in tape and drop it off at a battery recyler.

 

[Punk In Drublic]

I shadow the other comments on discarding the cell. But I would also investigate why that low voltage cut off did not kick in. If the mod is defective, I’d consider discarding it as well. Keep in mind with a regulated device, as the battery voltage drops, the current draw on the battery increases. If you are unaware of exceeding the low voltage cut off, continued use may stress the battery.

 

[Gallant]

But I would also investigate why that low voltage cut off did not kick in. If the mod is defective, I’d consider discarding it as well.

Seems like the mod was defective I discarded both the mod & battery.
Thanks all.