Going along with Ira's suggestion, I have experimented with a variety of rechargeable batteries over the years and while I have not kept the detailed records necessary for a truly scientific study, I have generally found the longevity of rechargeable NiMH batteries to be about â…” that of alkaline batteries when they are new. Unfortunately that lifespan gets shorter as the batteries are recharged again and again. But a recharged NiMH is noticeably longer lived than even a brand new NiCad. I have also experimented with the so called "long life" or "extra life" alkaline but I could not tell any significant difference between their lifespan and that of the less expensive alkalines such as gold top Duracells or Ray-O-Vac Ultra Pros.
