Slip stream for reliable anode to cathode flow in freeze conditions

A fuel cell system comprising:

• a fuel cell stack comprising a plurality of fuel cells each of which comprises an anode to accept a hydrogen-bearing fluid, a cathode to accept an oxygen-bearing fluid and a medium cooperative with said anode and said cathode to pass at least one catalytically-ionized reactant therebetween;
• an anode flowpath in fluid communication with said anode;
• a cathode flowpath in fluid communication with said cathode;
• and
• a three-way valve fluidly cooperative with said anode flowpath and said cathode flowpath, said valve comprising:
• at least one actuation mechanism to establish selective introduction of said hydrogen-bearing fluid from said anode flowpath into said cathode flowpath;
• and
• a flow controlling orifice configured to control anode flow into said cathode flowpath such that in an environmental condition where water present in said flowpath and valve may be frozen, said orifice is responsive to the enhanced pressure of said slip stream fluid such that any frozen water situated thereon is removed by a flexing action of said orifice in response to said passage of said slip stream therethrough.

A method of operating a fuel cell system, said method comprising:

• configuring a valve to be fluidly cooperative with an anode flowpath and a cathode flowpath of said fuel cell system, said valve comprising at least one actuation mechanism and a flow controlling orifice;
• passing a pressurized slip stream through said orifice such that in an environmental condition where water present in at least one of said anode flowpath, cathode flowpath and valve may be frozen, said orifice flexes in response to the enhanced pressure of said slip stream such that any frozen water situated thereon is removed by said flexing;
• and
• introducing a hydrogen-bearing fluid to said cathode flowpath from said anode flowpath through said at least one actuation mechanism and said orifice.