Single Pressure Vessel Life Test Update

Eagle-picher Technologies (EPT) nickel-hydrogen batteries and battery cells have been subjected to many and varied lik cycle tests. Both real time and accelerated tests in Low Earth Orbit as well as Geosynchronous Orbit test regimes have been perform& In most cases, these tests attempt to represent the on-orbit chargddiischarge profile of the application as closely as passiile, as well as test for extreme conditions. This test database was originated in support of early mckel-hydrogen flight programs and has been comktently expanded over the past twenty years several new nickel-hydmgeu cell and battery designs are on test including the Single Pressure Vessel (SPV). Even though the basic stack components are very similar to traditional cells designs, such as the Independent Pressure Vessel (PV), the packaging concept for this battery is significantly merent and thus requires additional life testing. Thm are cumntly two SPV batteries on life test at EFT. The SOAH, 22 volt battery has accumulated 27,723 cycles at 3Ph depth of discharge (DOD). The @AH, 22 volt battery has accumulated 24,705 cycles, at 26% DOD. Both Wes am showing stable performance and are projected to deliver cycle life peafonnance similar to 1PV cells.