The Space Experiment Program involved the design, development, manufacture, qualification and flight test of a fully instrumented, 21-cell (voltage equal to a 22-cell Ni-Cd battery), 50 Ahr Ni-H//2 battery. Launched on a low earth orbit satellite mission, the battery was successfully subjected to multiple shallow, intermediate and deep depth-of-discharge cycles (including reversal) demonstrating compliance with preflight electrical and thermal performance projections.