What happened to my battery?

Question

Last night, the weirdest thing happened. I had a 9v battery on my computer desk and it EXPLODED! It made 3 loud snaps..all at different times. The first time I just thought it was something outside. The second time I knew it had to be something in my room, then the third time some papers flew off my computer desk!! I finally realized all the battery powder and contents were all over the place! I have no idea why it did that. Could someone inform me?

Answer 1

The two connectors on top of the battery were probably both touching a piece of metal (coin, keys, side of computer case, etc). This created a short circuit, causing the battery to overheat. Since regular batteries are sealed, there was no way for the heat to escape, so it kept expanding until....

This is not a problem with regular batteries, like AA or C, because the + and - connectors are on opposite ends of the battery.