Abstract: A fuel cell stack includes an endplate assembly having a structural endplate. An insulator plate has a second exterior surface contacting a first interior surface of the structural endplate and a second interior surface on an opposite side of the insulator plate. A third plate has a third exterior surface contacting the second interior surface and a third interior surface on an opposite side of the third plate relative to the insulator plate. The third interior surface and third exterior surface are substantially flat. The second interior surface and the third exterior surface contact each other substantially continuously in a longitudinal direction and a lateral direction, and are flat and substantially parallel to each other. The second exterior surface is contoured such that the second exterior surface is not flat and is substantially non-parallel relative to the third interior surface.

Abstract: A fuel cell stack includes an endplate assembly having a structural endplate. An insulator plate has a second exterior surface contacting a first interior surface of the structural endplate and a second interior surface on an opposite side of the insulator plate. A third plate has a third exterior surface contacting the second interior surface and a third interior surface on an opposite side of the third plate relative to the insulator plate. The third interior surface and third exterior surface are substantially flat. The second interior surface and the third exterior surface contact each other substantially continuously in a longitudinal direction and a lateral direction, and are flat and substantially parallel to each other. The second exterior surface is contoured such that the second exterior surface is not flat and is substantially non-parallel relative to the third interior surface.

Abstract: A fuel cell stack includes an endplate assembly having a structural endplate. An insulator plate has a second exterior surface contacting a first interior surface of the structural endplate and a second interior surface on an opposite side of the insulator plate. A third plate has a third exterior surface contacting the second interior surface and a third interior surface on an opposite side of the third plate relative to the insulator plate. The third interior surface and third exterior surface are substantially flat. The second interior surface and the third exterior surface contact each other substantially continuously in a longitudinal direction and a lateral direction, and are flat and substantially parallel to each other. The second exterior surface is contoured such that the second exterior surface is not flat and is substantially non-parallel relative to the third interior surface.

Abstract: A fuel cell stack includes an endplate assembly of a fuel cell system which includes a structural endplate having a first exterior surface and a first interior surface located on an opposite side of the endplate relative to the first exterior surface. An insulator plate has a second exterior surface contacting the first interior surface of the structural endplate and second interior surface on an opposite side of the insulator plate relative to the second exterior surface. A third plate has a third exterior surface contacting the second interior surface and a third interior surface on an opposite side of the third plate relative to the insulator plate. The third interior surface and third exterior surface are substantially flat such that third interior surface and the third exterior surface are about parallel to each other.

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 spring loaded direct oxidation fuel cell assembly reduces the effects of precompression relaxation. A near flat spring and a distribution plate form a spring assembly that is disposed between a membrane electrode assembly and one of the current collectors in the fuel cell. The components are assembled into a fuel cell assembly and are precompressed, and a spring yielding process is performed. While precompression is being applied, a set of pins and a plastic frame are insert molded around the fuel cell assembly to hold the components in place. Subsequently, as the precompression relaxes, the spring assembly forces act to maintain an evenly distributed compression on the MEA, thereby compensating for the loss of precompression. A related method of manufacturing a fuel cell assembly is provided.

Abstract: A fuel cell system having internal pushback of water, with a compact, thermally integrated enthalpy exchanger enabling effective hydration control in a small fuel cell system is provided. The enthalpy exchanger provides for the moisture in the fuel cell effluent to be used to humidify the incoming air stream to allow the fuel cell to be operated at higher temperatures while avoiding dry out. The enthalpy exchanger includes a moisture permeable membrane which collects moisture from the exhaust flow and makes this moisture available to an incoming air stream, thus humidifying the incoming air stream. In addition, the waste heat from the fuel cell reactions is transferred to the incoming air stream. The exhaust stream from the anode can also be used to provide additional moisture and heat to the enthalpy exchanger to be added to the incoming air stream. A water separator is also provided in one embodiment.

Abstract: A heat spreader assembly that provides electrical, thermal and structural functions to the fuel cell. The heat spreader assembly comprises two bulk composite material layers, and a heat spreader element. The heat spreader element includes a copper layer sandwiched between two stainless steel layers. The stainless steel layers are bonded to the bulk composite layers by a conductive thermal set adhesive. The lamination applied to the stainless steel layers enables heat and electricity to flow from the cathode while maintaining low resistance among other layers of the fuel cell. The copper layer diffuses heat across the layer and functions as cathode current collector for a fuel cell. The bulk composite material layers function as a cold side of an enthalpy exchanger system and a cathode flow field. Further the composite material includes flow channels formed throughout the material to evenly distribute incoming air over the enthalpy exchanger membrane and to the cathode of the MEA.

Abstract: An electrochemical actuator system includes a membrane electrode assembly coupled to a source of electrical energy. The membrane electrode assembly includes a proton-exchange membrane disposed between a first electrode and a second electrode. A first chamber is located on a first side of the membrane electrode assembly and is configured to hold a gas generated by applying electrical energy to the first electrode of the membrane electrode assembly. The membrane electrode assembly and the first chamber are sealed to inhibit fluid communication with the surrounding ambient environment. The chamber includes a diaphragm deformable in response to a change in an amount of the gas in the first chamber. A deformation of the diaphragm in response to the change in the amount of the gas in the first chamber causes a movement of an actuating member coupled to the diaphragm.

Abstract: A heat switch system includes a first surface thermally coupled to at least a portion of an associated component requiring temperature control. A second surface is spaced by a gap relative to the first surface. A gas generator is coupled to a first chamber configured to hold a gas generated by the gas generator. The first chamber includes a diaphragm configured to be deformed in response to an increase in an amount of the gas in the first chamber. A deformation of the chamber in response to the increase in the amount of the gas in the first chamber causes movement of the first surface and/or the second surface such that the first surface and the second surface move toward each other to reduce the gap and heat is transferred from the first surface to the second surface.

Abstract: A valve system includes a gas generator coupled to a first chamber and a passage for conveying a flow of fluid therethrough. The first chamber is configured to hold a gas generated by the gas generator. The chamber includes a diaphragm deformable in response to an increase in an amount of the gas in the first chamber received by the gas generator. A deformation of the diaphragm in response to the increase in the amount of the gas in the first chamber inhibits flow of the fluid through the passage.

Abstract: A wide-area electrostatically-actuated shutter is provided that includes a thin, flexible, diaphragm that is placed between two rigid electrode structures. In one embodiment of the invention, the diaphragm has a set of openings in it. These openings overlap with corresponding openings in one of the rigid electrodes such that when the diaphragm is contiguous to that electrode, the openings provide apertures through which vaporous fuel can flow. The opposite electrode does not have overlapping openings, thus it forms a seal that prevents gas or vapor from passing through it when the diaphragm is in contact with the opposite electrode. The shutter is actuated electrostatically by an associated driver that applies a voltage to the diaphragm such that when the high voltage is applied to the diaphragm, the diaphragm is attracted to the fixed electrode that is tied to ground.

Abstract: A fluid flow plate for a fuel cell includes a first face and a fluid manifold opening for receiving a fluid and at least one flow channel defined within the first face for distributing a reactant in the fuel cell. A dive through hole is defined in and extends through the fluid flow plate. The dive through hole is fluidly connected to the fluid manifold opening by an inlet channel, defined within an opposite face of the plate. The dive through hole and the inlet channel facilitate transmission of a portion of the fluid to the flow channel. A groove, adapted to receive a sealing member, is also defined within the first face and/or the opposite face. The sealing member may comprise a gasket which seals the respective fluid manifolds, thereby preventing leaking of fluid.

Abstract: A hydration system for a fuel cell includes a fluid flow plate having an inlet fluid opening for receiving a hydration fluid, a plurality of reactant flow channels defined in the fluid flow plate, at least one land interposed between the flow channels, and at least one hole defined in and extending through the land. The hole may be fluidly connected to the inlet fluid opening, thereby allowing a portion of the fluid to aid in hydration of a membrane of the fuel cell. A hydration channel also formed in the land may extend from an outlet of the hole to further aid membrane hydration.

Abstract: A fuel cell stack assembly includes a stack of fuel cell flow plates that include fluid passageways; pipes to communicate fluids with the fluid passageways; an end plate; and a dielectric manifold. The end plate supports a compressive load to compress the stack, and the end plate includes openings. The manifold is located between the end plate and the stack to communicate the fluids between the pipes and the fluid passageways. The manifold at least partially extends through the openings in the end plate to form a sealed connection between the manifold and the pipes.

Abstract: An end plate assembly is disclosed for use in a fuel cell assembly in which the end plate assembly includes a housing having a cavity, and a bladder receivable in the cavity and engageable with the fuel cell stack. The bladder includes a two-phase fluid having a liquid portion and a vapor portion. Desirably, the two-phase fluid has a vapor pressure between about 100 psi and about 600 psi at a temperature between about 70 degrees C. to about 110 degrees C.

Abstract: In one aspect, a first (flow field) plate of a fuel cell assembly includes a first flow channel(s) thereon. Fluid is conducted to the flow channel through an opening extending through the first plate. An adjacent second plate cooperates in providing surface(s) for a flow path between a manifold and the opening. Additional surface(s) may cooperate in providing the flow path and/or structural support therefor. A formation on the first plate may impede fluid communication from the manifold plate on a plate face including the first flow channel. The formation may provide structural support in a (e.g., PEM-type) fuel cell assembly, and/or a clamping and/or gasketing function for a membrane electrode assembly. A second flow path may similarly be provided for humidification of the (e.g., reactant) fluid. The second flow path may include flow regulator(s) and/or metering orifice(s). The second plate may include a second flow channel thereon.

Abstract: A hydration system for a fuel cell includes a fluid flow plate having an inlet fluid opening for receiving a hydration fluid, a plurality of reactant flow channels defined in the fluid flow plate, at least one land interposed between the flow channels, and at least one hole defined in and extending through the land. The hole may be fluidly connected to the inlet fluid opening, thereby allowing a portion of the fluid to aid in hydration of a membrane of the fuel cell. A hydration channel also formed in the land may extend from an outlet of the hole to further aid membrane hydration.

Abstract: In one aspect, a fuel cell assembly may include one or more (e.g., PEM-type) fuel cell(s). Fluid(s) service(s) for the fuel cell assembly may include reactant fluid(s) service(s) such as service(s) of fuel(s) and/or oxidant(s), along with humidification service(s). A pulsator may be positioned at any entrance and/or exit for the fluid manifolds. Such pulsator(s) may serve to introduce pressure variation(s) along part(s) of flow path(s) extending in the fuel cell assembly. In one example, with respect to an anode side of a fuel cell, the pressure variation(s) may serve to purge a nitrogen blanket from the anode side of the MEA so reformate including hydrogen may be supplied for electrochemical reaction. With respect to a cathode side of the fuel cell, the pressure variation(s) may serve to remove a nitrogen and/or carbon dioxide blanket and product fluid from the cathode side of the MEA so air containing oxygen may be supplied for the electrochemical reaction. Also, excess humidification fluid may be removed.