I've never had an 18650 Li-ion cell go off on me, but I have had LiPo cells decompose while still strapped to my drone and those produce copious amounts of thic

I've never had an 18650 Li-ion cell go off on me, but I have had LiPo cells decompose while still strapped to my drone and those produce copious amounts of thick smoke (which I'm told is not great for you in confined spaces)