| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately detect the charged state of a secondary battery, when a bypass circuit is on-operated in the secondary battery having an equalizing process with the bypass circuit. SOLUTION: A plurality of secondary batteries D1-D4 are serially connected and bypass circuits 12, 14, 16 and 18 are respectively connected in parallel with each secondary battery. An ECU 10 on-operates the bypass circuit, in order to equalize the state of charge(SOC) of the secondary batteries D1-D4. During the bypass circuit is on-operated, the ECU 10 detects the charging condition not using the terminal voltage, but detects the charging condition based on the terminal voltage, or the current accumulated value when the bypass circuit is in the off state. |
