90 Ah Dependent Pressure Vessel (DPV) Nickel Hydrogen Battery Qualification Test Results

In 1995, the Naval Research Laboratory (NRL) began a program to investigate whether a 90 Ah dependent pressure vessel (DPV) NiH₂ battery pack could be a lower volume replacement for a 90 Ah NiH₂ IPV spacecraft battery. Nickel Hydrogen (NiH₂) dependent pressure vessel (DPV) battery cells are presumed to offer all the features of the NiH₂ IPV battery cell with considerably less volume. To achieve this reduction in volume, the DPV cell utilizes a canteen shaped pressure vessel with reduced thickness wall, flat sides and curved ends. The cells can be packaged similar to prismatic nickel cadmium battery cells. Moreover, like NiCd cells, a fully charged DPV cell must rely upon an adjacent battery cell or structure for support and to maintain pressure vessel integrity.

Seventeen 90 Ah NiH₂ DPV cells were delivered to NR in 1998 for qualification tests. An eleven-cell half battery pack was manufactured and tested to validate the advantages of the DPV design. This paper will discuss the results of the cell level tests, qualification test requirements, the 11-cell battery pack design and qualification test results.