The Clementine Nickel Hydrogen Common Pressure Vessel Battery

The Clementine spacecraft was launched in January 1994 to demonstrate advanced lightweight technologies for the Ballistic Missile Defense Organization (BMDO). One of the key technologies was the first use of a multi-cell nickel hydrogen (NiH2) common pressure vessel (CPV) battery. The 5.0 inch diameter, 22 cell, 15.0 ampere-hour NiH2 CPV battery was manufactured by Johnson Controls Battery Group Inc., (JCBGI). Battery test and integration was performed by the Naval Research Laboratory (NRL). The battery was mounted to the spacecraft using a unique, lightweight graphite epoxy structure. An integral mounted pressure transducer provided battery pressure data for a pressure based charge control method. Along with the structure and the charge control method, this paper will discuss the battery design trade study, pre-launch battery data and on-orbit performance data.