Lithium Battery Pack Teardown

For reasons not relevant here, I tore down a battery pack containing three 18650 lithium cells. After a major struggle that involved drilling access holes into the side of the case and hammering the cells free of their silicone potting restraint, I was confronted with this:

Li-ion cell - unwrapped
Li-ion cell – unwrapped

Battery may explode or fire if mistreated. Yeah, that could happen.

Having pretty well ignored all the warnings, the damaged cells spent two days in the cold on the patio:

Li-ion cells - safety layout
Li-ion cells – safety layout

They seem unchanged, so I’ll dispose of them at the next electronics recycling event.

As it turns out, the gadget containing the pack subsequently died of a whoopise while trying to figure out how the pack’s boost regulator worked, so it joined the cells on the outgoing pile.

So it goes …