Everything was going along fine; I parked my car for a few hours.
Never left anything electrical on, and when I got back and tried to
start the car the battery was completely (And I mean completely - no
dome lights, dashboard lights, etc.) dead [The battery is 7 years
old]. I got a jump and with the alternator supplying electricity
everything was fine. After driving for an hour when I got home the
battery was just as dead. I put a voltmeter across the terminals and
it only registered 7.5 volts (I would have tested it with a
hydrometer, but the battery is completely sealed). I have since put in
a new battery and everything works fine.
I thought batteries died gradually. How does a battery die suddenly,
and does this happen often? With any other battery I owned it