bouncer33441
Newly Enlightened
- Joined
- Mar 12, 2011
- Messages
- 94
i removed 6 18650 cells from an old laptop battery . is there a way to tell if each is good or bad , and can i try charging them to see ?
against better judgement
- Thread starter bouncer33441
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TooManyGizmos
Flashlight Enthusiast
~
Test each one with a volt meter . Any that are lower than 2.5 volts might
"Vent with Flames" while being charged .
( I can't remember the actual low-voltage threashhold for being un-safe
to charge ... but I use 2.5 v. as a minimum .)
The battery experts here can give more details than I .
~
Test each one with a volt meter . Any that are lower than 2.5 volts might
"Vent with Flames" while being charged .
( I can't remember the actual low-voltage threashhold for being un-safe
to charge ... but I use 2.5 v. as a minimum .)
The battery experts here can give more details than I .
~
Last edited:
ToyTank
Enlightened
I think salvaging old laptop cells is a bad idea. That said I would only mess with them on a large concrete pad with nothing flammable around. Maybe you have a li-po charging bag or a steel box but some protection would not be a bad idea.
1. Check voltage. I'd also toss any that are below 2.5v.
2. Check the Date code. Most makers it is 4 digits likely MMYY or WWYY. IMHO if they are older than 4 years I'd toss them as they chances of failure are higher.
3.If you charge them full with CC/CV charger and they do not hold over 4.1V after 24hr toss them. If they hold around or under 4.0 that is <80% and the chance of a vent with flames or rapid disassembly increases dramatically.
4. It is a bit more difficult but you could check the internal resistance of the battery. There are threads here for that. Not sure when they are considered bad, but internal resistance will increase as ICR cells age.
-This thread should be in "flashlight electronics-batteries included" sub forum
1. Check voltage. I'd also toss any that are below 2.5v.
2. Check the Date code. Most makers it is 4 digits likely MMYY or WWYY. IMHO if they are older than 4 years I'd toss them as they chances of failure are higher.
3.If you charge them full with CC/CV charger and they do not hold over 4.1V after 24hr toss them. If they hold around or under 4.0 that is <80% and the chance of a vent with flames or rapid disassembly increases dramatically.
4. It is a bit more difficult but you could check the internal resistance of the battery. There are threads here for that. Not sure when they are considered bad, but internal resistance will increase as ICR cells age.
-This thread should be in "flashlight electronics-batteries included" sub forum
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