Previous generations of rechargeable AA (pencell) batteries suffered a number of limitations, i.e. capacity, (mAhr/unit volume), high self discharge rates, (both Nicads and Nickel Metal Hydride), poor current delivery and drop off at low temperatures. Sanyo have addressed all these issues with their new Eneloop cells. These cells have an extremely low self discharge rate, higher current delivery, capability and a superior performance at low temperatures, particularly important when winter flying. Added to this is an extended service life of up to 1000 cycles.