Patent ID: 7143724

Claim:
A power supply device for driving a motor which is mounted on a vehicle and makes the vehicle travel, the power supply device comprising: a battery unit having a plurality of secondary batteries; a battery temperature sensor for detecting a temperature of at least one of the secondary batteries included in the battery unit; a heat insulating mechanism for controlling the temperature of the secondary batteries; an outside air temperature sensor for detecting the temperature of air outside of the vehicle; an intake port for taking in the outside air so that it can be circulated in the battery unit; an intake valve for opening/closing the intake port; an exhaust port for exhausting the outside air taken in from the intake port and circulated in the battery unit; an exhaust valve for opening/closing the exhaust port; and a temperature controller for controlling opening/closing of the intake valve and the exhaust valve on the basis of a temperature difference between the outside air temperature detected by the outside air temperature sensor and the battery temperature detected by the battery temperature sensor, wherein the intake port and the exhaust port are disposed so as to be adjacent to each other to form an air circulation path.