Abstract

A battery reconditioning system and method for a spacecraft which utilizes a single battery as a secondary source of power for spacecraft electrical loads (10). The battery (14) includes a plurality of serially connected packs (30-36) each including a plurality of cells (40-46) connected in series. Sensors (50-56) are provided with each pack for sensing the state of charge of the pack. Battery charging circuitry (12,18,20) is controlled from control circuitry (22,52) which is responsive to the state of charge sensors as well as commands from a ground station transceiver (57). Reconditioning resistors (60-66) are adapted to be connected across the individual packs through switches (70-76) which are controlled by the control circuitry to discharge the pack at a relatively high rate when reconditioning is desired. After a pack is discharged to a desired low state of charge, its reconditioning resistor is disconnected and all packs are recharged in series. A pair of diodes (80A,80B-86A,86B) are connected across each pack and provide a low resistance current path in the event a fault clearing current is required from the battery during reconditioning of a pack.