> time will be setup, but I need the battery to keep track of the time
> for 3~4 years at least. Can this CR2032 battery do this?

http://data.energizer.com/datasheets/library/primary/lithium_coin/cr2032.pdf

According to their test it will fall to 2.0V after 13 weeks @ 97uA

If you're looking at 208 weeks then you'd need to get down to 6uA

http://www.renata.com/pdf/3vlithium/DBCR2032.05.pdf

has a little more information, eg self-discharge, which is quite low

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