Something similar almost happened to me once, about 12-13 years ago… Back then we were still trying everything, so I had a bottom-fire mech mod, a Nico N-Storm, Hungarian made, with a factory spring-loaded bottom switch. The “Big Brain Árpád” ordered magnetic rings from Fasttech, because what a technocratic innovation it is to make the switch magnetic, plus a salvaged battery from a Samsung laptop for 300 forints… Yes, but the big brain left the locking ring open, and shoved it in his pocket before heading to work, and that’s when Murphy started his work… one of the quarter-dollar magnetic rings from Fasttech broke (I guess from the shaking), and it immediately flipped to the other side in the switch base and engaged the button… I noticed the mod was getting hot, and the cotton in the dripper had practically turned to dust by then. The coil was glowing red hot in the atomizer, heating up the entire mod and the battery too… I only had enough time to take the mod apart with a tissue, by then it was already hot, and the battery flew quite far into the middle of the street… It cooled down, thankfully it didn’t hiss.
Since then, only quality batteries and mods equipped with electronics.
Lesson learned: the battery doesn’t need to be damaged; the end-user can kill it too if they are careless…