BATTERY STATE ESTIMATION METHOD AND BATTERY STATE ESTIMATION DEVICE

A battery state estimation method is provided. The method includes a first charging step for charging a high-voltage battery until a full charge state is reached, a discharging step for discharging the battery from the full charge state to a lower-limit charge state and calculating a battery capacity of the battery by accumulating a discharge current during the discharging, a second charging step for recharging the battery from the lower-limit charge state to the full charge state, halting the charging for a predetermined period every time one of measuring points defined between the lower-limit charge state and the full charge state is reached, and measuring the OCV of the battery after a predetermined period has passed, and resuming the charging after the measuring is completed, and a correlation characteristic obtaining step for obtaining correlation characteristic of the battery based on SOC and the OCV measured at each measuring point.