[markdjacobsen]

I have the dubious distinction of having burned down three acres of Stanford's Lake Lagunita with a Li Po battery after crashing a drone (this was a soft pack for a DIY drone). We had been meticulous about charging and handling safety, but they still light off like fireworks if punctured. Seven years later, I'm still terrified of these batteries and treat them like explosives.

[kazinator]

You could start a fire with an ordinary alkaline battery used in the right way, and these things pack way more energy.