>>have a bunch of e-scooter 18650 battery packs

Where get?

There is a guy that rides the trail near me thats riding an ebike with a triangular battery pack that looks identical to one some HNer built here - He's too fast and I havent been able to stop him.

Another question for the DIY e-bik crowd, is what kind of OTS motor could one harvest, like a motor from an electric lawm mower, or edger, weed-wacker? Are there power tools where the electric motor is useable? (like how people originally used mower engines in goKarts and such?

Also, for fireproofing - mix Powdered Aerogel into a Silicon Slurry and dip the battery in that - the silicon and aerogel will make a heat sleeve thats quite fire resistant.