Sand is the best bet, unless you have a "D" class fire extinguisher for combustible metals.

I thought the ideal thing to do is run away screaming "FIREEEE!!!".

Urine is the best way to put out lipo fires. Also works for burns and cleaning cuts.

Most LiPo bags are just cheap imitations and don't do much, don't settle for anything else other than the original LiPo Sack.

LipoSack | LipoSack Storage and Charging Solutions

Demonstrational material:

https://www.youtube.com/watch?v=mw8jb1KmAG8

This is the only bag that is engineered to contain the flames, there is plenty of testimonials about it working as advertised.

Those look like they are made from Nomex or something similar. That makes sense as it's actual fireproof material unlike the plastic from which the Chinese LiPo bags are constructed. These bags are really expensive though. Cheap insurance, sure, but you can get an ammo box for the same price and that won't burn through.

neither do ammo containers or lipo bags. Containment!

Take one of your wife or mom's planting pots, rip out the plant, dig a hole in the center that can fit the battery. Apologize later, buy an even more expensive flower and try to get through the week, hopefully not the month. Not something she'll forget.

I use old Corning Pyrex casserole dishes I buy at garage sales. I get a few weird looks, but they are super cheap, non-conductive, and safer than a bag since they provide better heat containment:



I've also used a fireproof cash box similar to this:

6 tests are done in the first video https://youtu.be/CnNId0mDnBo
https://youtu.be/tH4fFA5zxww