FUEL CELL COOLANT OVER-PRESSURIZATION SYSTEM

A system includes a fuel cell stack. A liquid coolant loop is coupled to provide coolant to the fuel cell stack. An expansion tank is coupled to the coolant loop and has an expansion tank inlet to couple to a fuel cell stack cathode inlet. An inlet check valve has a relative cracking pressure dpin and is coupled between the fuel cell stack cathode inlet and the expansion tank inlet to over-pressurize the coolant in the coolant loop.