<p>The terminal voltages of battery cells 10-1 to 10-n constituting a set battery 10 are individually monitored by cell-voltage detecting circuits 11-1 to 11-n and input to a current control circuit 12. The current control circuit 12 detects any of the monitored terminal voltages that attains a level indicating a fully charged state. A variable constant-current control circuit 13 supplies a charging current ICH by regulating power output by a main power supply 14. As the current control circuit 12 detects a state in which one of the battery cells 10-1 to 10-n gets fully charged, the variable constant-current control circuit 13 stops charging current into the set battery 10. <IMAGE></p>
