MIL-PRF-81757D, PERFORMANCE SPECIFICATION: BATTERIES AND CELLS, STORAGE, NICKEL-CADMIUM, AIRCRAFT, GENERAL SPECIFICATION FOR (1 MAR 1999) [SUPERSEDING MIL-B-81757C]., This specification covers the general requirements for rechargeable, vented, nickel-cadmium aircraft storage batteries, cells, and all components (electrical and non-electrical) thereof.