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Spacecraft batteries are normally installed in the discharged condition. It may be necessary that they be charged and trickle-charged prior to launch in an environment different from that in which they are intended to operate; i.e., an environment in which the heat generated during charge and trickle charge is radiated to space. The purpose of the testing described herein was to determine the battery capacity achieved after treatment at prelaunch conditions as a function of charge rate, charge temperature, trickle charge temperature, and time. In this testing the discharge in every case was performed under simulated space thermal conditions. Charging was performed with a variety of battery starting temperatures, and heat dissipation was limited to that expected to be encountered under conditions of cooling with an air manifold. At the worst conditions of test, that is with 24°C (75°F) cooling air at the battery baseplate, 80 percent of the rated capacity was obtained.

Extended room temperature storage of nickel-hydrogen battery cells has resulted in a capacity loss when the cells are initially cycled following the storage period. Because it may be necessary to “store” nickel-hydrogen batteries for long periods at room temperature (i.e., shipment, installation, etc.), tests were performed to establish the effects on capacity recovery of several post-storage conditioning methods. The tests included two groups of cells; a 60-day storage group and 120-day storage group. Each group comprised three 2-cell packs. The capacity of each cell was measured under the same controlled conditions both prior to storage and after post-storage conditioning. Each 2-cell pack in a group was conditioned differently over a 13-day period following storage. The results attained with the 60-day storage group were essentially confirmed with the 120-day storage group.