Abstract: The invention provides a reactant delivery system for a dead-headed PEM fuel cell system, comprising a fuel cell, a fuel supply, a purge valve, an inlet orifice, an outlet orifice, and a controller. A first fuel flow circuit is provided, wherein fuel is flowed from the fuel supply to the inlet orifice, through the fuel cell from the inlet orifice, and through the outlet orifice from the fuel cell to the purge valve. A second fuel flow circuit is also provided, wherein fuel is flowed from the fuel supply to the outlet orifice, through the fuel cell from the outlet orifice, and through the inlet orifice from the fuel cell to the purge valve. A valve means is coupled to the controller and adapted to transfer fuel flow between the first flow circuit and the second flow circuit.

Abstract: The invention provides a reactant delivery system for a dead-headed PEM fuel cell system, comprising a fuel cell, a fuel supply, a purge valve, an inlet orifice, an outlet orifice, and a controller. A first fuel flow circuit is provided, wherein fuel is flowed from the fuel supply to the inlet orifice, through the fuel cell from the inlet orifice, and through the outlet orifice from the fuel cell to the purge valve. A second fuel flow circuit is also provided, wherein fuel is flowed from the fuel supply to the outlet orifice, through the fuel cell from the outlet orifice, and through the inlet orifice from the fuel cell to the purge valve. A valve means is coupled to the controller and adapted to transfer fuel flow between the first flow circuit and the second flow circuit.

Abstract: The invention generally relates to fuel cell reactant delivery systems and methods for delivering fuel to fuel cell systems, where air or oxygen is injected into a fuel stream containing hydrogen, such that a portion of the hydrogen reacts with the oxygen to form water that humidifies a fuel cell membrane as the fuel stream is passed into the fuel cell. In a preferred embodiment, the invention relates to dead-headed, pure hydrogen PEM fuel cell systems, but the invention is also applicable to other fuel cell system configurations.

Abstract: The invention provides a reactant delivery system for a dead-headed PEM fuel cell system, comprising a fuel cell, a fuel supply, a purge valve, an inlet orifice, an outlet orifice, and a controller. A first fuel flow circuit is provided, wherein fuel is flowed from the fuel supply to the inlet orifice, through the fuel cell from the inlet orifice, and through the outlet orifice from the fuel cell to the purge valve. A second fuel flow circuit is also provided, wherein fuel is flowed from the fuel supply to the outlet orifice, through the fuel cell from the outlet orifice, and through the inlet orifice from the fuel cell to the purge valve. A valve means is coupled to the controller and adapted to transfer fuel flow between the first flow circuit and the second flow circuit.