xevious wrote:I'm curious to know what typically causes watch batteries to leak. Do they all have the same potential to leak, or are just certain battery types more prone? I'm suspecting that the thinner the battery, the less chance for leakage due to less battery material... so, the big old button cell batteries might tend to be "watch time bombs". Will colder temperatures help prevent leakage and does very warm temperatures encourage leakage?
Unless defective, most batteries won't leak until they are dead - at that point their chemistry is generally reversed(alkalines become acid, acid types become alkaline). Popular Science had a great article on batteries about a12-18 months ago...I placed a link somewhere but can't find it....
Cold storage of batteries is tricky - their amprege potential drops greatly, so I would recommend you never test a watch you just pulled out of the mailbox until it has thoroughly warmed up. Otherwise, you may drain it substantially thru just a few displays...and the warming is not going to recover the same percentage of potential that the cold usage just took away. Real hot temps(left on car dashboard,etc. can cause some to 'puke'.
Regardless[virtually] of the outside temperature, the inside of your watch will be between 75-86 degrees faren.(due to your body giving off or absorbing heat, as the situation demands) - according to the American Watchmakers Institute.
I'm thinking a plastic back might throw that off a bit.