Patent ID: 9570924
Date: 2017-02-14
CPC Classifications: H01M,H02J,Y02E

Claim:
1. A battery pack comprising: a battery comprising at least one rechargeable battery; a control unit configured to monitor a state of the battery and to control at least one of charge and discharge of the battery; a pair of external terminals configured for an electrical connection of an external device; a first current cut-off unit provided in a power supply path that is formed by connecting the battery and the pair of external terminals and through which flows at least one of a charge current and a discharge current, the first current cut-off unit being configured to be turned to one of an energized state and a cut-off state based on a command from the control unit, to thereby turn the power supply path to one of an energized state and a cut-off state; and a second current cut-off unit that is connected in series to the first current cut-off unit in the power supply path and is configured to be turned to one of an energized state and a cut-off state based on a command from the control unit, to thereby turn the power supply path to one of an energized state and a cut-off state, wherein the control unit is configured to determine whether the first current cut-off unit and the second current cut-off unit are normal or abnormal when neither charge nor discharge of the battery is performed, and configured to turn the first current cut-off unit and the second current cut-off unit to an energized state when the first current cut-off unit and the second current cut-off unit are both normal, whereas configured to turn at least one of the first current cut-off unit and the second current cut-off unit to a cut-off state when the at least one of the first current cut-off unit and the second current cut-off unit is abnormal.