Abstract: In one embodiment, a membrane electrode assembly of a fuel cell has an anode aspect and a cathode aspect. A fuel distribution structure is disposed adjacent to the anode aspect. The fuel distribution structure has a fuel feed port configured to receive and inject liquid fuel to a flow field plate. The flow field plate has flow channels formed therein that split and spread from the fuel feed port to exit ports. The flow channels are configured to convey heat to fuel passing there through to substantially convert the liquid fuel to vaporous fuel within the flow channels. The exit ports are configured to deliver the resulting vaporous fuel to the anode aspect to substantially uniformly distribute fuel across the anode aspect. Further, an enthalpy exchanger and heat spreader assembly is in thermal contact with the fuel distribution structure and configured to provide to it heat from fuel cell operation.

Abstract: A fuel cell system which includes a fuel distribution structure that uniformly distributes vaporizing fuel to a fuel cell is provided. As the fuel travels in a flow field channel in the fuel distribution structure, it is substantially converted to a vapor by the heat of the fuel cell operation in such a manner that the resulting vapor pressure works to substantially uniformly distribute fuel evenly outwardly across substantially the entire active area of the anode aspect of one or more membrane electrode assemblies in the system, and whereby localized, uneven “hot spots” of fuel at the anode aspects are substantially prevented. A pair of enthalpy exchanger and heat spreader assemblies include a cathode current collector element that also has a heat spreader plate that collects and redirects heat in the fuel cell system, the assembly acting to manage the heat, temperature and condensation in the fuel cell system.

Abstract: A fuel cell system which includes a fuel distribution structure that uniformly distributes vaporizing fuel to a fuel cell is provided. As the fuel travels in a flow field channel in the fuel distribution structure, it is substantially converted to a vapor by the heat of the fuel cell operation in such a manner that the resulting vapor pressure works to substantially uniformly distribute fuel evenly outwardly across substantially the entire active area of the anode aspect of one or more membrane electrode assemblies in the system, and whereby localized, uneven “hot spots” of fuel at the anode aspects are substantially prevented. A pair of enthalpy exchanger and heat spreader assemblies include a cathode current collector element that also has a heat spreader plate that collects and redirects heat in the fuel cell system, the assembly acting to manage the heat, temperature and condensation in the fuel cell system.

Abstract: A single pump fuel cell system is provided that has multiple valves that have selective positioning to control fluidic flow throughout a fuel cell system. One of the valves provides for high and low concentration fuel dosing. Another valve or series of valves controls an unreacted fuel recirculation loop leading from the fuel cell. Another valve or series of valves control condensate collection by the fuel cell system, and allows the purging of the anode recirculation loop. Each of the valves is selectable between various positions to place the fuel cell system in a desired operating mode. A heat exchanger may also be employed to dissipate heat as desired out of the fuel cell system. A concentration sensor can also be employed to aid in achieving a desired fuel concentration within the fuel cell system.