The power system of the Hubble Space Telescope includes two orbital replacement units, each containing three nickel-hydrogen (Ni-H2) batteries of 88 Ah capacity. Since launch in April 1990, the batteries have completed 23000 charge and discharge cycles and continue to meet the power demands of the satellite. The voltage, capacity, and pressure characteristics of all six batteries were analyzed to determine the state of health of the battery and to identify any signs of performance degradation. The battery pressures have changed to varying degrees. The end-of-charge pressure for battery 4 increased by 96 psi, while that for battery 3 decreased by 37 psi. The voltages of the individual cells show a decay rate of 0.69 mV per 1000 cycles, and the capacity of the batteries has apparently decreased, possibly due to the system being operated at a lower stage of charge. Autonomous battery operation involving charge termination at a preselected voltage continues to restore the energy dissipated during each orbit. The accumulated data on voltages and recharge ratios can be used to design new temperature-compensated voltage levels for similar missions that employ Ni-H2 batteries.
Voltage and capacity stability of the Hubble telescope nickel-hydrogen battery
Spannungs- und Kapazitätsstabilität der Nickel-Wasserstoff-Batterie des Hubble-Teleskops
Journal of Power Sources ; 58 , 1 ; 7-14
1996
8 Seiten, 6 Quellen
Aufsatz (Zeitschrift)
Englisch
Voltage and capacity stability of the Hubble telescope nickel-hydrogen battery
Online Contents | 1996
|Nickel-hydrogen battery testing for Hubble Space Telescope
Tema Archiv | 1989
|