Abstract: A battery pack including a battery and a battery protection circuit is disclosed. In one aspect, the battery protection circuit comprises a protective device configured to inhibit a flow of current between an electrode of the circuit and the battery when activated. The battery protection circuit further comprises a primary protection circuit and a secondary protection circuit. The primary protection circuit is configured to generate a control signal for control the protective device when detecting an abnormal voltage in a unit cell of the battery. The secondary protection circuit is configured to activate the protective device, either when receiving the control signal from the primary protection circuit or when detecting an abnormal voltage in a unit cell of the battery.