I sure hope you threw the battery outside when it got hot. Those type's of batteries are like pressure vessels when they explode. It's not uncommon to get flames over 2m out of these things when they vent!
As a matter of fact I did, I didn't wanna go to bed knowing that thing was at my bedside lol.
I don't know what the outcome would have been, but I seen a video online of a laptop battery blowing up, I know inside those laptop batteries are multiple 18650's.
It was rather scary, the embering metal was like a fuse that could blow up any second.