heating a cap

I got a small (under 1" long) aluminum electro cap, 220 uF 63v, and
cranked up the voltage. It started drawing a bunch of current at 105
volts, got hot, and folded back to 80 mA at 87v.

It got too hot to touch in a couple of minutes, after roughly 500
joules. Freeze spray let it go back up to 100 volts or so.

None of that seemed to damage it, so an electrolytic cap sort of has a
built-in MOV.