To provide a vehicle power source device in which a battery can be cooled down efficiently in an optimal condition while making small a power consumption and the battery can be cooled down efficiently and prevent an abnormal temperature rise even under conditions of charging and discharging in a large current and a high external temperature.

The vehicle power source device is provided with a plurality of unit cells 1 arranged in a predetermined distance, a cooling duct 3 which is arranged between the unit cells 1 and coveys air for cooling the unit cells 1, a cooling fan 4 for conveying air compulsorily into the cooling duct 3, a heat exchanging pipe 5 arranged between the unit cells 1, a liquid circulating unit 6 for circulating a heat exchanging liquid to the heat exchanging pipe 5 and cools or warms the unit cells 1, and a controlling circuit 7 for controlling the cooling fan 4 and the liquid circulating unit 6. The controlling circuit 7 detects a battery temperature or a heat generation amount and cools down the battery by switching into a driving status where the cooling fan 4 only is driven and a liquid circulating drive status where the liquid circulating unit 6 only is driven, and a cooling fan and liquid circulating status where both of the cooling fan 4 and the liquid circulating unit 6 are driven.

COPYRIGHT: (C)2009,JPO&INPIT