APPARATUS AND METHOD FOR ESTIMATING BATTERY STATE OF CHARGE

The present invention relates to estimating a state of charge of a battery. An apparatus for estimating a state of charge of a battery according to the present invention includes: a measurement unit which measures a current and a voltage of a battery; a current integration unit which estimates the state of charge of a battery by integrating charged or discharged currents with respect to a preset initial value of the state of charge of a battery; a memory which includes information on a correlation between an open circuit voltage of the battery and the state of charge and information about the open circuit voltage in the case of being converted for a period of time when the battery is in a resting state; and a control unit which calculates a voltage corresponding to a preset micro error range from the open circuit voltage, sets a reset time for initializing the current integration process of the battery by using the calculated voltage; resets the initial value of the state of charge which is a standard of the current integration by using the calculated voltage based on whether or not the battery stays in the resting state for more than the reset time, and controls the current integration to restart based on the reset initial value.