Battery Short?

[lx-missile]

I have a '91 5.0 LX. On the way home, the radio cut out a couple of times, then I started hearing a noise under the hood. When I turned off the road, the electrical system shut down (gauges, fuel pump, everything cut off.)

When I had it pulled home, I thought the battery might be the problem. Started to unhook it, and found the positive side hot (and getting hotter). We yanked the cable and swapped the battery with another one and the problem seems to be solved.

My question is this: the bad battery was a few years old, is it possible that it just went south on its own, or is this thing a fire waiting to happen?

Thanks in advance!