Abstract: Disclosed are methods for fabricating a reinforced membrane electrode assembly having one or more freestanding external reinforcement layers. The method comprises providing a freestanding external reinforcement layer, and depositing a catalyst solution and membrane solution onto at least a portion of the freestanding external reinforcement layer.

Abstract: A fuel cell includes an ion conducting membrane having a first side and a second side. Characteristically, the ion conducting membrane has a sufficient amount of a stabilization agent and platinum to inhibit the loss of fluoride from the ion conducting membrane when compared to an ion conducting membrane having the same construction except for the presence of cerium ions.

Abstract: A fuel cell includes an ion conducting membrane having a first side and a second side. Characteristically, the ion conducting membrane has a sufficient amount of a stabilization agent and platinum to inhibit the loss of fluoride from the ion conducting membrane when compared to an ion conducting membrane having the same construction except for the presence of cerium ions.

Abstract: One aspect of the invention includes the discovery that pinholes in the membrane of the membrane electrode assembly may be caused by hygroexpansive ratcheting. In one embodiment of the invention, a fuel cell stack including a plurality of cells each having a membrane electrode assembly each including a membrane manufactured by an extrusion method and operated so that the rate of drying during humidity cycling is sufficiently low to reduce or eliminate build up stresses in the membrane electrode assembly.

Abstract: The present invention is directed to addressing performance issues attributable to membrane electrode assemblies, and the components thereof, in electrochemical conversion cells. In accordance with one embodiment of the present invention, a device comprising at least one electrochemical conversion cell is provided. The cell is configured to convert first and second reactants to electrical energy and comprises a membrane electrode assembly and at least one membrane reinforcement layer. The combination of elastic modulus and thickness of the reinforcement layer and the bond between the reinforcement layer and the membrane electrode assembly are sufficient to enhance the structural integrity of the membrane electrode assembly beyond the operational degradation threshold of the assembly.

Abstract: An apparatus removes carbon monoxide (CO) from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies of proton exchange membrane (PEM) fuel cells. A vessel houses a carbon monoxide adsorbent. The vessel may be a rotating pressure swing adsorber. A water gas shift reactor is upstream of the rotating pressure swing adsorber. The water gas shift reactor may include a second adsorbent adapted to adsorb carbon monoxide at low temperatures and to desorb carbon monoxide at high temperatures. The apparatus advantageously eliminates the use of a preferential oxidation (PROX) reactor, by providing an apparatus which incorporates CO adsorption in the place of the PROX reactor. This cleans up carbon monoxide without hydrogen consumption and the concomitant, undesirable excess low grade heat generation. The present invention reduces start-up duration, and improves overall fuel processor efficiency during normal operation.

Abstract: An apparatus removes CO from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies. Both a catalyst adapted to perform a water gas shift reaction, and a carbon dioxide adsorbent are disposed in a rotating pressure swing adsorber housing. The adsorption of carbon dioxide shifts equilibrium toward carbon monoxide consumption. A second adsorbent may be disposed in the housing for adsorbing carbon monoxide at low temperatures, and is adapted to desorb carbon monoxide at high temperatures. The present invention advantageously eliminates a unit operation from a space-constrained fuel cell vehicle by combining the WGS catalyst and a CO2 adsorbent in a single reactor/housing. The apparatus further eliminates the use of a PROX reactor, by providing an apparatus which incorporates CO2 adsorption and consequent carbon monoxide consumption in the place of the PROX reactor.

Abstract: A fuel processor system contains an autothermal reactor (ATR) that produces a hydrogen-rich first gas stream containing carbon monoxide. Downstream of the ATR, a pressure swing adsorber produces a second hydrogen-rich gas stream containing 5 ppm carbon monoxide or more. Downstream of the PSA, there is a methanation reactor sized to reduce the CO level of the second stream below 5 ppm. A method of operating of proton exchange membrane fuel cell stack involves cooling the methanator output and feeding it into the stack as an anode fuel.

Abstract: A PSA unit for purifying hydrogen in a fuel processor system. The PSA unit employs rotary valves that cycle the pressurization of vessels, including an adsorbent, between a high pressure state and a low pressure state. The purified hydrogen is released from the vessels through a purified gas output port when the vessels are in the high pressure state and the impurities are released through an exhaust port when the vessels are in the low pressure state. The PSA unit also employs a mass flow control device and a pressure sensor in the purified gas output port. A controller receives a pressure signal from the pressure sensor, and controls the flow through the mass flow control device and the speed of the rotary valves so that the proper pressure is maintained at the hydrogen output port.

Abstract: A PSA system that purifies a feed gas, such as a reformate gas in fuel cell system. The PSA system includes a series of vessels housing an adsorbent or combination of adsorbents that adsorb carbon monoxide, carbon dioxide, nitrogen, water and methane in the reformate gas. The adsorbent vessels are connected to each other and a feed manifold, a product manifold and an exhaust manifold through suitable conduits, where the gas flows are controlled by a product rotating valve and feed rotating valve or a series of open/shut valves. A specialized PSA cycle controls the valves so that the vessels cycle through various stages of equalization, blow-down, purge, pressurization and production to purify the feed gas.