CHARGER, CHARGING SYSTEM, AND CHARGING METHOD

This charger is provided with: a power supply unit that charges a secondary battery; an acquisition unit that acquires individual identification information for identifying the secondary battery; a comparison unit that compares the individual identification information acquired when starting the charging of the secondary battery with individual identification information acquired at the termination time of a past charging cycle. The power supply unit terminates the charging of the secondary battery on the basis of the results of comparison.