I've had Sony, and Panasonic CR2032 lithium batteries last quite a while in various unused motherboards. Believe the Panasonic battery was unused for 2 years in some discarded motherboard, but it was *still* good. It was used quite a bit before that as well. As a matter of fact, one of my Saturns has been using this battery for a few months without a problem.

As far as the batteries from Radio Shack go....I've been less than satisfied. My oldschool PocketStation (little Sony LCD device for Playstation) used to eat the "Made in Switzerland" batteries from Radio Shack. At 3 bucks a pop this becomes a little costly. I'd recommend picking up a Made in Japan CR2032 (possibly a Panasonic, or Sony), or trying to find out which lithium batteries are used in medical equipment, such as heart monitors etc. Good luck.
**Also, as with all batteries it's not great to short them by touching + and -. Best to hold the battery from the sides, not that it would matter much for a few seconds.
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