Patent ID: 7971447

Claim:
A cooling system for a vehicle battery, comprising: a cooling loop in heat transfer communication with the battery, for removing heat therefrom with a coolant; a first cooling device selectively coupleable to the cooling loop, using a refrigerant fluid to transfer heat with the coolant; a second cooling device selectively coupleable to the cooling loop, using ambient air to transfer heat with the coolant; temperature determining components for determining an ambient temperature and a battery temperature; a valve for directing the coolant to at least a selected one of the first and second cooling devices; and a controller for implementing a coolant flow bypass function to limit a temperature gradient between the coolant and the battery to a selected threshold by commanding operation of the valve to bypass the selected one of the cooling devices in response to at least one of the battery temperature and the ambient temperature, wherein the selected threshold is a gradient beyond which damage to the battery is possible.