What do you expect when buying crap, using a crap charger like that, next to a TV on a wood table? Fortunately, Mother Nature has a way of selecting out who's genes get passed on.
The charger looks like one of those awful DX cheapies. I had one of those, and it not only doesn't cut off when the charge is complete, it doesn't even slow down. I'm not surprised a nasty 1300mAh battery gave it up while in that deathtrap.