A cooling system and method for cooling a battery in a vehicle is provided. The method includes determining whether the cooling system is operating to cool a passenger compartment in the vehicle, operating the cooling system to cool the battery when it is determined that the cooling system is operating to cool the passenger compartment, and it is determined that at least one predetermined condition is met. The method also includes determining whether an engine in the vehicle is operating, and then operating the cooling system to cool the battery when it is determined that the engine is operating and a battery temperature is greater than a predetermined battery temperature.