POWER SUPPLY APPARATUS

A power supply apparatus (10) includes a first battery (310), a second battery (320), and an ECU (100) configured to determine whether conditions i), ii), and iii) are satisfied; i) a degree of deterioration of the second battery (320) is lower than a first threshold; ii) an SOC of the second battery (320) is lower than a second threshold; and iii) the SOC is equal to or greater than a third threshold. The second threshold is higher by a prescribed value than a lowest allowable value of the SOC at which the second battery (320) can function as a backup power supply. The third threshold is the lowest allowable value. When determining that the conditions i), ii) and iii) are all satisfied, the ECU (100) executes single-battery-using control in which regeneration control using the regenerative electric power is executed with use of the first battery (310) and the second battery (320) is not used for the regeneration control.