BATTERY PACK, AND BATTERY PROTECTING METHOD

摘要

A battery pack is enabled to execute a battery protection action of higher safety. It is discriminated at any time whether or not there exist a plurality of abnormal states including an overcharged state and an overdischarged state, which are based on the detection results of a voltage between the positive pole and the negative pole of a battery cell, and an overcurrent charged state and an overcurrent discharged state, which indicate it on the basis of the detection results of the charge and discharge currents of the battery cell that the charge current and the discharge current are individually excessive, and malfunction deciding flags indicating the discrimination results of the individual abnormal states as flags are held. Moreover, control states (A to D) according to the combinations of the individual action states of a discharge current blocking circuit for blocking the discharge current of the battery cell selectively and a charge current blocking circuit for blocking the charge current of the battery cell selectively are defined to decide it on the basis of the values of the malfunction deciding flags what control state a transition is made to.