Good LiPo bags work for small batteries. The batteries in most ebikes would burn through those. You can find video tests that show this. For ebike-sized batteries you need an ammo can. Even then if you want to ensure your home doesn’t get poisoned with fumes, it should be in a ventilated area, garage or outside.

I’m not sure I learned anything from watching this video. My biggest fear is a battery igniting when Im asleep or not at home.

For RC car batteries, you need something called a “bat-safe”, which will also filter the smoke to a certain extent.

In the case of an E-bike or e-scooter, those batteries are far too big, and often integrated into the frame, which makes them nearly impossible to fully protect without total isolation.