I buy my Lithium Batteries from The Source (formerly Radio Shack). For an extra couple of bucks they'll sell you an 'all perils' warranty on any house brand 'specialty' lithium battery like the 123. If the cell goes dead inside of 2 years they replace it no questions asked.

Obviously the warranty was concieved when devices which used 123 lithium cells only sipped the juice....not like today's 100 Lumen mega-LED flashlights. I get the equivalent of 2 batteries for the price of 1.

Ironically with the cheap prices of mail order these days, it's almost cheaper to buy via the internet as even the house brand cells at The Source are slightly overpriced.