Slightly off topic, but I have a bunch if Li ion batteries for gardening equipment, with some of the batteries are becoming old. Regrettably none of these have an expiry date to judge when they should be returned for recycling, leaving only poor charging as indication the battery should go to recycling, so I keep them in a fire/explosion proof bag. Also, when I charge any new device, like an iPhone, I try to enclose it in one of the bags in case there is some sort of manufacturing fault.
A house in my town burned to the ground from a faulty scooter battery that blew and the resulting fire took out the adjacent house as well because of high winds fanning the flames....