Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: A subassembly for a fuel cell includes a fuel cell plate having a first side and a second side. Each of the first side and the second side has a flow field disposed between a pair of headers. An insulating spacer abuts the first side of the fuel cell plate and is disposed adjacent a perimeter of the fuel cell plate. A unitized electrode assembly includes a subgasket, a membrane electrode assembly, and a pair of diffusion medium layers. The membrane electrode assembly has an electrolyte membrane sandwiched between a pair of electrodes. The membrane electrode assembly is sandwiched between the pair of diffusion medium layers. The subgasket surrounds, and is coupled to, the membrane electrode assembly. The subgasket abuts the insulating spacer. An elastomeric seal abuts the second side of the fuel cell plate.

Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: Methods for attaching a subgasket to an ionomer membrane, wherein the methods provide for the precise location of the subgasket relative to the other component edges of the fuel cell, such as the catalyst layers, so as provide the functionality required to extend the ionomer membrane life and prevent damage to the ionomer membrane during the assembly process.

Abstract: A unitized electrode assembly for a fuel cell comprising an electrolyte membrane and a subgasket. The subgasket maximizing an operating life of the electrolyte membrane, militating against adverse effects of membrane expansion during use of the fuel cell and membrane shearing under unitized electrode assembly compression.

Abstract: A subassembly for a fuel cell includes a fuel cell plate having a first side and a second side. Each of the first side and the second side has a flow field disposed between a pair of headers. An insulating spacer abuts the first side of the fuel cell plate and is disposed adjacent a perimeter of the fuel cell plate. A unitized electrode assembly includes a subgasket, a membrane electrode assembly, and a pair of diffusion medium layers. The membrane electrode assembly has an electrolyte membrane sandwiched between a pair of electrodes. The membrane electrode assembly is sandwiched between the pair of diffusion medium layers. The subgasket surrounds, and is coupled to, the membrane electrode assembly. The subgasket abuts the insulating spacer. An elastomeric seal abuts the second side of the fuel cell plate.

Abstract: A membrane electrode assembly includes a membrane layer, a cathode or anode catalyst layer adjacent to a surface of the membrane layer, an anode or cathode catalyst layer adjacent to an other surface of the membrane layer, an adhesive layer adjacent to the other surface of the membrane layer, wherein the adhesive layer abuts a surface of the anode or cathode catalyst layer, and a subgasket layer having an edge portion, wherein the subgasket layer is adjacent to a surface of the adhesive layer, wherein the cathode catalyst layer and anode catalyst layer extend along a length of the membrane layer relative to the edge portion of the subgasket layer, wherein the cathode or anode catalyst layer extends a greater length along the length of the membrane layer than the anode or cathode catalyst layer relative to the edge portion of the subgasket layer.

Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: A fuel cell system that employs a two-position valve at the cathode exhaust gas output for controlling the pressure within the fuel cell stack to control the stack relative humidity. In one embodiment, the two-position valve is switchable between a fully open and a fully closed position, where the valve is opened when the fuel cell system is operating at a low operation temperature and the valve is closed when the fuel cell system is operating at a high operation temperature. A fixed restriction valve is provided in parallel with the two-position valve so that when the two-position valve is fully closed, the proper amount of pressure is provided at the cathode output. In another embodiment, the two-position valve employs sized leak paths so that when the two-position valve is in the closed position, the cathode exhaust gas can still flow through.

Abstract: A method for controlling the pressure within a fuel cell stack to control the stack relative humidity. In one embodiment, a two-position valve receiving the cathode exhaust is switchable between a fully open and a fully closed position, where the valve is opened when the fuel cell system is operating at a low operation temperature and the valve is closed when the fuel cell system is operating at a high operation temperature. A fixed restriction valve is provided in parallel with the two-position valve so that when the two-position valve is fully closed, the proper amount of pressure is provided at the cathode output. In another embodiment, the two-position valve employs leak paths so that when the two-position valve is in the closed position, the cathode exhaust gas can still flow through.

Abstract: A unitized electrode assembly for a fuel cell comprising an electrolyte membrane and a subgasket. The subgasket maximizing an operating life of the electrolyte membrane, militating against adverse effects of membrane expansion during use of the fuel cell and membrane shearing under unitized electrode assembly compression.

Abstract: A fluid delivery device for an electrochemical conversion assembly. In one embodiment, the electrochemical conversion assembly is a fuel cell system. The device includes one or more fluid-manipulating components combined into a housing to minimize weight, size and complexity. In one form, the device may include a compressor, heat exchanger and a water vapor transfer unit, at least the latter two of which are located within a chamber defined by the housing. A controller can be used to monitor and selectively vary the extent to which at least one of these components modifies properties a fluid (such as air) that can be used as a reactant in the electrochemical conversion assembly. In a particular form, the heat exchanger and water vapor transfer unit can cooperate to promote the hydration of the reactant.

Abstract: A process for fabricating a unitized electrode assembly for a polyelectrolyte membrane is disclosed. The process includes providing a gas diffusion medium and a membrane electrode assembly, printing an adhesive on the gas diffusion medium, locating the gas diffusion medium relative to the membrane electrode assembly and pressing the gas diffusion medium and the adhesive against the membrane electrode assembly.

Abstract: A UEA for a fuel cell having an active region and a feed region is provided. The UEA includes an electrolyte membrane disposed between a pair of electrodes. The electrolyte membrane and the pair of electrodes is further disposed between a pair of DM. The electrolyte membrane, the pair of electrodes, and the DM are configured to be disposed at the active region of the fuel cell. A barrier film coupled to the electrolyte membrane is configured to be disposed at the feed region of the fuel cell. The dimensions of the electrolyte membrane are thereby optimized. A fuel cell having the UEA, and a fuel cell stack formed from a plurality of the fuel cells, is also provided.

Abstract: A non-functional fuel cell for a fuel cell stack includes a shim disposed between gas diffusion media, a bipolar plate at one end, and either a bipolar plate or a unipolar plate at the other end. The shim of the non-functional cell replaces the membrane electrode assembly (MEA) in a normal fuel cell located in the middle or the end of the fuel cell stack. The shim is coated with electrically conductive, corrosion-resistant protective coating. The shim may be cleaned prior to applying the protective coating to remove an oxide layer from the surface of the shim. The non-functional fuel cell may be included in the initial design of the fuel cell stack, or may be used to replace one or more damaged or inoperative fuel cells to increase the overall performance of the fuel cell stack.

Abstract: Methods for attaching a subgasket to an ionomer membrane, wherein the methods provide for the precise location of the subgasket relative to the other component edges of the fuel cell, such as the catalyst layers, so as provide the functionality required to extend the ionomer membrane life and prevent damage to the ionomer membrane during the assembly process.

Abstract: A fuel cell system that employs a two-position valve at the cathode exhaust gas output for controlling the pressure within the fuel cell stack to control the stack relative humidity. In one embodiment, the two-position valve is switchable between a fully open and a fully closed position, where the valve is opened when the fuel cell system is operating at a low operation temperature and the valve is closed when the fuel cell system is operating at a high operation temperature. A fixed restriction valve is provided in parallel with the two-position valve so that when the two-position valve is fully closed, the proper amount of pressure is provided at the cathode output. In another embodiment, the two-position valve employs sized leak paths so that when the two-position valve is in the closed position, the cathode exhaust gas can still flow through.