In a bizarre set of circumstances that would not make sense if described, I abruptly moved a Lith-ion battery pack.
Similar to a drop-kick, but not intentional...
To my shock and dismay, the heavy nylon zipper pouch that it was in started to smoke and got very hot, really fast
I pitched it all out a 2nd story window and grabbed a flashlight running out the front door into the rain to inspect it.
Not surprised that over time the heat-shink insulation at the pack-wrap had receded
The enameled wires were touching and the jolt had cut insulating enamel enough to start it off.
It thermally ran-away, melting the cell wrap, overwrap and scorched and melted a bit of the bag.
The PSA?:
Inspect your packs!
Especially where the leads exit the cells, and where they exit the cell bundle.
No serious damage, but lost $40 of cells and a really awful stink.
I could easily see how if unnoticed in storage that a house fire would have been possible.
I'm considering using RTV (silicone) or epoxy at the wire entrance locations for my other packs.
Maybe even fireproof holders?
Enameled wire?
What were they thinking?...