ELECTRIC POWER SOURCE DEVICE

摘要

A cooling fan (30) of a secondary battery (10) and a cooling fan (40) for a DC/DC converter (20) are parallelly arranged and share the same gas discharge path (80). On the secondary battery (10) are installed an air intake side temperature sensor (12) and a gas discharge side temperature sensor (14). When the cooling fan (30) is in failure, a temperature deviation between the air intake side and the gas discharge side in the secondary battery (10) becomes greater because of that routing around component (95) of a discharge gas (90) which comes through the gas discharge path (80) as the cooling fan (40) operates. Based on this phenomenon, when operation commands for both cooling fans (30, 40) are already issued, a control circuit (50) detects the failure of the cooling fan (30) by monitoring the difference between temperatures (Tb1, Tb2) detected by the temperature sensors (12, 14). Failure detection is possible without installing a sensor on each cooling fan.