Did I kill my RCR123????

[jgraham15]

I was using my NiteCore Extreme at work today and ran down my CR123A primary and the only other batteries I had with me were unprotected RCR123's. I installed one of the unprotected RCR123's in my Extreme knowing I shouldn't (it doesn't have over discharge protection) and forgot about it until my flashlight started flickering. I pulled the RCR123 out and checked the voltage and it was at 2.153 volts. Is it safe to recharge it? Or is it junk?
Oh by the way it is a 3.7v RCR.

Thanks for your help!

 

[NigelBond]

Did the voltage recover back up to something close to 3v after a few minutes? You should even be able to see it slowly climbing while you test it. If it remains at 2.153, i would probably toss it.

 

[mdocod]

The more time it spends in that state of over-discharge the more damage is done.

An over-discharge like that is not good for the cell, however, in most cases if the cell is charged soon after there is no significant loss in capacity or safety of the cell. Repeated deep discharges or storage at <~3.5V is what leads to worn out unsafe LiCo cells.

The cell is technically less safe now than it was before the incident (talking fractions of a percent more than likely but none-the-less). I wouldn't personally worry too much about it if the cell is relatively new. If these unprotected cells are already a few years old and have a lot of use on them, then this wouldn't be a bad excuse to trade-up to some fresh ones just for peace of mind.

-Eric