Originally Posted by
slawecki
pull the battery, vacuum seal it and put it in your deep freeze.
No joke. Run the battery down to about 1/2 life. Then wrap it in a paper towel and then cool it down in the fridge briefly. To make sure that nothing condenses on it in case you live in a humid climate. Then put the whole wrapped thing inside a ziplock bag and leave it in the fridge, NOT the freezer.
That will extend the battery the longest.