I don't get why so few people put smoking/burning power banks in a tub of water (on air planes and honestly in general). it's the same thing we do with smoking/burning EVs; it cools the battery cells and stops the reaction, and contains the smoke and fire. The water doesn't cause problems the runaway thermal reaction hasn't already caused. It seems silly, but if you have a battery that catches on fire, AFAIK the best thing you can do is to dunk it into a bucket or tub and fill it with water.