Nickel-hydrogen (Ni-H/sub 2/) single pressure vessel (SPV) battery development update

Abstract

The Ni-H/sub 2/ battery system is recognized for its long life, reliability and durability. Eagle-Picher Industries, Inc. (EPI) has developed the Single Pressure Vessel (SPV) Ni-H/sub 2/ battery, which houses all cells within a single vessel, as an evolutionary step in Ni-H/sub 2/ technology. The SPV configuration was developed to improve the performance, producibility and reliability of the Ni-H/sub 2/ system at the battery level, and ultimately to reduce overall battery cost and weight. Recognition of the benefits and advantages of the SPV resulted in its choice as the battery design for a large-scale communications satellite program. After instituting high-volume production procedures and undergoing a significant life test effort at EPI, this program is proceeding very smoothly, on time and on cost. This particular application requires a 22 cell, 60 Ah low Earth orbit (LEO) battery, however, 50 Ah, 30 Ah and 15 Ah battery configurations have been produced and capacities up to 120 Ah are possible with a short development time. An accelerated (70% depth-of-discharge for 4612 cycles) life test of an early prototype and an independent design review have both shown the design to be robust. The advanced SPV battery has the flexibility to fulfil the requirements of any mission needing a reliable, durable, space-qualified battery with a high duty cycle capability. This presentation discusses SPV design features and presents life test data. Also addressed are the production features of the SPV battery which have resulted in cost and performance benefits for the IRIDIUM(R) global communications system.