Well, wasn't that a fun experience...
I have a whole bunch of 18650 cells harvested from various laptop battery packs. So far, after reading an awful lot on info on these pages, I've had absolutely no issues. I've always double checked charge states with a DMM, never charged batteries unattended, always disposed of bad cells, and generally adhered to all of the cardinal rules for Li-ion safety.
Until yesterday...
I was building a P60 module to run a single 5mm LED for a long life glow-light. while testing it to see what the current draw was, I was getting 13.5A reading on the DMM!
While I was getting this reading, I noticed the LED wasn't lit. Stupidly, I tried again, to see if I was imagining things.
After getting the same reading, I stopped and dismantled the light. I was greeted by a smell I'll not soon forget.
Turns out I'd dead shorted the battery, and the DMM was completing the circuit. The load to the circuit presented by the DMM probably saved me from exploding the cell. Either way, the battery had vented and had gotten hot enough for the shrinkwrap to start burning.
I very quickly took the battery outside to let it cool off, and have since disposed of it.
That's close enough for me!
I have a whole bunch of 18650 cells harvested from various laptop battery packs. So far, after reading an awful lot on info on these pages, I've had absolutely no issues. I've always double checked charge states with a DMM, never charged batteries unattended, always disposed of bad cells, and generally adhered to all of the cardinal rules for Li-ion safety.
Until yesterday...
I was building a P60 module to run a single 5mm LED for a long life glow-light. while testing it to see what the current draw was, I was getting 13.5A reading on the DMM!
While I was getting this reading, I noticed the LED wasn't lit. Stupidly, I tried again, to see if I was imagining things.
After getting the same reading, I stopped and dismantled the light. I was greeted by a smell I'll not soon forget.
Turns out I'd dead shorted the battery, and the DMM was completing the circuit. The load to the circuit presented by the DMM probably saved me from exploding the cell. Either way, the battery had vented and had gotten hot enough for the shrinkwrap to start burning.
I very quickly took the battery outside to let it cool off, and have since disposed of it.
That's close enough for me!
