The video you linked is problems that can happen and things that can go wrong. It seems more like something the battery makers should watch instead of proof that batteries are inherently unsafe.
The person who linked it was saying it is evidence of batteries being unsafe because it goes over things that can go wrong.
I was saying it's educational for battery makers and the video isn't about batteries being unsafe, the guy in the video makes his own batteries and is talking about what to avoid.
