I may be the last to know, but I had never heard that rechargeable batteries needed loving care to stay in shape. It turns out that you can ruin a rechargeable battery by running it down to zero. The polarity of the battery cells can even become reversed, ruining the battery for future charges. The fix is to remove and recharge a battery the minute a loss in power is detected—I can't tell you how many mysteries this is solving for me! You must also guard against radical temperatures, high or low. Don't leave batteries in your garage during the winter or in a hot car that can heat up to over 100 degrees. Finally, keep metal objects away from your batteries because contact will drain the power. Watch where batteries are stored, whether in drawers or a tool belt. Also, consider protecting the ends with plastic to prevent accidental contact and power loss.