18650 flammability by a shell vaporizing test

[SniperGaulois]

I set fire to a a Sanyo cell from 2018 in a controlled environment, I melted through the steel using a 100A current, by placing some battery terminals on either side of the negative terminal. The battery flashed as the steel and copper vaporized, and then it started burning the lithium inside. It was burning in the same way as plastic inside the battery with a small resiliant flame on top, no sparks and runaway blaze. I put it the flame out by blowing on it or using a rag, and after a while it went cold, revealing transparent electrolyte gel and a gap in the battery shell.

I don't recommend this test for old batteries because they are too explosive, but it can be fun for people that want to check about flammability of the most recent models.

It would be good to have a standard test to vaporize a zone of the battery shell, please give results if you have time for it.

 

[flippy]

i run them dead to 0 volts and then i put 10V on it with basically unlimited amps. the good stuff (samsung 29E, panny PF's and so on) dont explode. at best you get some venting and a possible flame if the fumes can ignite.
the cheap crap from china is usually a lot more "energetic" and i usually put some lexan shielding in front of those so you dont get headshotted by a exploding cell.

its a great party piece when trying to show customers the difference between brandless 0.8 dollar cells and 3 dollar cells from a decent brand.

 

[dogman dan]

They do burn better when you have about 1800 wh on fire.

 

[flippy]

They do burn better when you have about 1800 wh on fire.

surely they do, but cheap cells tend to explode, that is a lot harder to control then just a lot of venting gases/flames.

 

[Hillhater]

Arc’ing a hole in the can removes the possibility of pressure build up and potential explosion.
It is one type of potential failure but not the same as a severe overvoltage which generates high internal heat and pressure before some thermal event...venting or explosion with flames etc.
There are many videos of even Tesla cells (the best ?) blasting off like rockets when overcharged to the point of thermal runaway.
And yes, different chemistry’s can behave very differently.