[z991]

> there is no 'battery safety box' that I could readilly buy

Take a look at Bat-Safe LiPo boxes. They are designed to contain the heat and prevent your entire house from going up from a drone battery fire.

[TT-392]

Bought one of these a while ago, super happy with the peace of mind these things provide. (I am using it mostly for drone batteries). I hope I'll never have to find out how well it actually works first hand though.

[ClumsyPilot]

okay, their largest box is actually big enough to deal with am ebike battery, this could work!