Patent ID: 7495416

Claim:
A battery pack composed of a secondary battery integrally with a processing circuit to perform processes including protection against error occurrence in the secondary battery, the battery pack comprising: discharge current cutoff means for selectively cutting off a discharge current in the secondary battery; charge current cutoff means for selectively cutting off a charge current in the secondary battery; protection process means for controlling operations of the discharge current cutoff means and the charge current cutoff means at least in accordance with an inter-electrode voltage between positive and negative electrodes of the secondary battery, wherein when it is determined that the secondary battery is placed in the overcharge state, the charge current cutoff means cuts off the charge current, and when it is determined that the secondary battery is placed in the over-discharge state, the discharge current cutoff means cuts off the discharge current, thereby protecting the secondary battery against abnormal states such as an overcharge and an over-discharge; startup-enabling voltage detection means for generating a detection signal when a power supply voltage supplied to the protection process means reaches a lowest voltage to start the protection process means, wherein the protection process means performs an initialization process in accordance with detection of a detection signal from the startup-enabling voltage detection means; and nonvolatile storage means for rewritably storing configuration values for the initialization process of the protection process means as needed, wherein the configuration values are stored in an active software memory which is read immediately after the protection process means starts.