I pulled the battery as it was acting funny, thinking terminal resistance was the problem. Even though it showed 12.5 volts sitting there, under any load it went down to 8, so had a dead cell or two or high resistance. The battery sat in the back of my truck, in the shade, on an 80 degree day, for over 6 hours before I went to get a new one at 9PM. It was still hot. Guessing the issue is an internal short drawing current and making heat. Luckily, it was still under warranty and got a new one for free, leaving the hot one in the shop. Told the guy, hope it didn't burst into flames and burn the place down. Anybody else have an issue like this?
In answer to the main question, yes I have experienced this. The battery was utterly trashed, the vehicle would never crank. But, we were on a work crew and had to get cracking so we jumped it every morning. The battery was always hot in the mornings before we jumped it and eventually it popped while driving, steam/smoke came pouring through the AC vents. Not pretty. Good call replacing it, hopefully it discharges before it gets hot enough to pop.