A system and method for improving the performance of a hybrid power supply apparatus comprising a power generating device, such as a fuel cell, and a primary energy storage device, such as a battery. The purpose of the invention is to provide an equalization charge to the battery from a source other...http://www.google.co.uk/patents/US6559621?utm_source=gb-gplus-sharePatent US6559621 - Hybrid energy storage device charge equalization system and method
