Battery control by update of current profile

A SOC acquisition unit (1) acquires a SOC of a battery. Then, it estimates a capacity profile from the acquired SOC, and transmits the estimated capacity profile to an estimation unit (2). The estimation unit (2) calculates a current profile for realizing the capacity profile estimated by the SOC acquisition unit (1). An update unit (3) replaces the existing stored current profile with the current profile calculated by the estimation unit (2). A storage unit (4) stores a current profile calculated by the estimation unit (2) and updated by the update unit (3). A charging unit (5) reads the current profile stored in the storage unit (4), and performs a charging operation based on the current profile.