Nickel-metal hydride replacement for VRLA and vented nickel-cadmium aircraft batteries

Military aircraft currently use valve regulated lead-acid or nickel-cadmium rechargeable batteries to perform a number of auxiliary functions such as; providing electrical power for emergencies, instrumentation, lighting, ground power, auxiliary power unit (APU), and occasionally engine starting. There is increasing interest in developing batteries, which are capable of higher energy density, maintenance free operation and do not contain highly toxic materials. This presentation describes the status of the development of a bipolar nickel-metal hydride battery to fulfil these objectives. The design approach provides batteries with three times the capacity within the same size and weight of the 24 Volt, 7.5 Ah lead-acid battery presently used in the F-18-A-D, F-117 and the H-46 helicopter. These batteries would also be suitable for the F-16-A-D and the F-18-E-F, which require a larger capacity battery with some hardware modifications.