POWER-SUPPLY DEVICE

摘要

PROBLEM TO BE SOLVED: To efficiently output power stored in a plurality of battery blocks to a discharge line while resolving the unbalance of residual capacity of the battery blocks.SOLUTION: A power-supply device includes a plurality of power-supply units 1 connected in parallel between a charge line 3 and a discharge line 8, and controls the power-supply units 1 by a control circuit 2. Each power-supply unit 1 includes: a battery block 4 charged by power of the charge line 3; a charging circuit 5 for charging the battery block 4; an output circuit 6 for stabilizing and outputting an output voltage of the battery block 4; and a battery controller 7 for detecting residual capacity of the battery block 4 and for controlling the output circuit 6. The control circuit 2 identifies the output circuit 6 that is in an operating state by the residual capacity of the battery block 4. The output circuit 6 that is in the operating state stabilizes a voltage of the battery block 4 and outputs the voltage to the discharge line 8, whereas the output circuit 6 that is in a stop state stops discharging of the battery block 4 and outputs predetermined power from the battery block 4 of the power-supply unit 1 to the discharge line 8.