I almost had my pants catch fire when I swapped out a battery on a smoke detector and dropped the old one in my pants pocket. A few minutes later I felt something hot in my pocket and I reached in and found the 9v battery had shorted on some change in my pocket.
Even batteries that may be 'dead' can still have the potential to do harm if they overheat.
>>
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> By Mike Hughlett
>> Tribune staff reporter
>> July 13, 2006
>> It has the ring of an urban legend: A cell phone blows up and sets >> fire to a house.
>> [TELECOM Digest Editor's Note: For those people inclined to think that
>> a fire caused by an exploding battery is 'just another urban legend'
>> which never has any verifiable source to it, here is an instance where
>> proof is available: Chicago Tribune, July 13, 2006 Section B, with a
>> real person named. PAT]
> There was a recent incident where a Dell laptop went up in flames
> at a conference in Asia.
> It's amazing how hot a 9 volt transistor battery gets when it
> contacts the loose change in your pocket.
> Energy = Energy
> Uncontrolled Energy = Bomb
[TELECOM Digest Editor's Note: Well, Mister Hot-Pants-a-Fire, I presume there was no damage of any sort to your essential parts down there; you did not have to call the Fire Department to put it out, did you? I know ... its not funny ... but it _is_ funny! PAT]