Maintenance-free nickel-cadmium batteries

High-rate Nickel-Cadmium aircraft batteries have been built and tested using sealed Ni-Cd cells. The batteries compare quite favorably with vented batteries. The Maintenance Free Batteries are capable of being charged in one hour or less over a temperature range of -40/spl deg/C to +60/spl deg/C. They will withstand the same environmental stresses as their vented counterparts, and are capable of discharging over the temperature range -40/spl deg/C to +70/spl deg/C with low impedance up to a 40 C rate. The batteries have been built and tested in sizes ranging from 5 to 70 Ampere-Hours and are suited to handle all requirements of all aircraft. They are constructed so as to be equivalent in price to high-rate vented batteries.