Another issue that hasn't been _explicitly_ pointed out is that if you're getting a new battery, make sure that it's as fresh as possible (i.e. recent manufacture.) Many places like to sell the oldest ones first, for obvious reasons. There are ways of checking the date codes, and you can Google for that. A seller that has a lot of throughput is a good bet (not the corner shop blowing the dust off it, etc.)
Walmart OTOH has good throughput, and is at least good for giving you a new battery every year, but it gets tiresome after a while. ;^)
Google "Walmart Vlasic Pickles bankruptcy" and you can see the kind of pressures that companies are under that deal with them.