Development of the large diameter (5.5") nickel-hydrogen battery cell

The Nickel-Hydrogen (NiH2) battery system is used extensively in the aerospace industry for power storage in earth-orbital satellites for communications, observation, scientific and military applications. The NiH2, system offers potential cycle life unequaled by any other system. A new technology 5.5 inch diameter NiH2, ceil is being developed for aerospace applications. Based on extensive individual Pressure Vessel (IPV) technology heritage accumulated from millions of hours of on-orbit performance, the large diameter cell will demonstrate increased specific energy and energy density as well as reduced weight, cost and design risk for the new generation nf high power satellites requiring capacities greater than 200 Ampere-Hours (Ah). In this paper we will discuss design features and concepts. Design and production issues and details will be discussed with regard to similarities and differences from smaller diameter IPV cells currently in production. We will present data from development cells which are currently undergoing life cycletesting to assess the reliability of the product as well as acceptance testing which provides meaningful information about lot to lot consistency achieved in production. Planning and execution of cell and battery qualification testing will also be discussed. Additionally, the next step in large diameter, high capacity NiH2 IPV cells is presently being developed. This paper will discuss design features and examine preliminary test data from that advanced development program.