Process for evaluating remaining capacity of battery

摘要

A process for evaluating a remaining capacity of a battery includes the steps of measuring a discharge current and output voltage from the battery during discharging of the battery, calculating a maximum output value of the battery based on a characteristic of the variation in discharge current and output voltage determined from the measured values of the discharge current and output voltage, and evaluating the remaining capacity of the battery based on the calculated maximum output value. The evaluation of the remaining capacity of the battery by this process is prohibited in a sudden-load-varying state in which the variation in load of the battery during discharging of the battery exceeds a predetermined limit level. Thus, it is possible to properly evaluate the remaining capacity of the battery without obtaining or using unstable voltage information of the battery immediately after the load varies suddenly, thereby leading to an enhanced accuracy of evaluation of the remaining capacity.