A power supply device includes a refrigeration cycle having a compressor, a motor, an inverter-integrated charger, a heat exchanger unit, and a controller having a determining unit. The inverter-integrated charger selectively controls operation of the motor using electrical power of a battery and charge of the battery with external power. The heat exchanger unit cools a cooling-necessary part of the inverter-integrated charger using refrigerant in the refrigeration cycle. When the vehicle is stopped and the battery is charged with the external power, the controller makes the inverter-integrated charger serve as: a charger to perform the charge of the battery; or an inverter to control the operation of the motor, thereby driving the compressor, upon determination that the cooling-necessary part needs to be cooled by the determining unit.