Abstract: A fuel cell system having partial and/or total redundancy of at least one operational component, such as a redundancy of fuel cell stacks and/or fuel processors. In some embodiments, the fuel cell system includes a plurality of fuel cell stacks adapted to deliver the same maximum rated power output as a comparative fuel cell system having only a single fuel cell stack. In some embodiments, the fuel cell system includes a plurality of fuel cell stacks adapted to deliver more than the maximum rated power output of the comparative fuel cell system. In some embodiments, the fuel cell system includes a plurality of fuel cell stacks having at least n+1 (or total) redundancy compared to a fuel cell system having only a single fuel cell stack. In some embodiments, the fuel cell system includes a control system and/or structure adapted to limit the applied load to the system.

Abstract: A feedstock mixing apparatus for fuel processing systems, and fuel processing and fuel cell systems incorporating the same. A fuel processing system according to the present invention includes one or more fuel processors adapted to produce a product hydrogen stream from a feed stream containing water and a carbon-containing feedstock. The fuel processing system further includes a feedstock delivery system adapted to mix the components of the feed stream at a determined mix ratio and to deliver this feed stream to the fuel processor(s). The fuel processing system may also include one or more fuel cell stacks that are adapted to produce an electric current from the product hydrogen stream produced by the fuel processing system. When the fuel processing system includes at least one fuel cell stack, it may be referred to as a fuel cell system.

Abstract: A system and method for preventing damage to a fuel cell stack resulting from impurities in a hydrogen stream delivered thereto. In some embodiments, the hydrogen stream is a product hydrogen stream from a fuel processor. In some embodiments, the impurities may result from a failure or malfunction in a separation region adapted to remove impurities in the hydrogen stream. The system and method include detecting the concentration of at least one component of the hydrogen stream and isolating the fuel cell stack should this concentration exceed an acceptable threshold level. In some embodiments, the system or method are adapted to detect the concentration of a component that itself is not harmful to the fuel cell stack, or which is not harmful in an associated threshold concentration. In some embodiments, the detected composition is at least one of water, methane, and carbon dioxide.

Abstract: Hydrogen purification devices, components thereof, and fuel processors and fuel cell systems containing the same. The hydrogen purification devices include an enclosure, such as a pressure vessel, that contains a separation assembly adapted to receive under pressure a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. In some embodiments, the enclosure is sealed without gaskets. The separation assembly includes at least one hydrogen-permeable and/or hydrogen-selective membrane, and in some embodiments the hydrogen-selective membrane is permanently and directly secured to the enclosure. In some embodiments, the membrane is welded, diffusion bonded or brazed directly to the enclosure. In some embodiments a portion of the hydrogen-selective membrane forms a portion of the sealed enclosure, and, in some embodiments, an interface is formed from consumed portions of the hydrogen-selective membrane and the enclosure.

Abstract: Fuel cells and fuel cell systems that include at least one non-aqueous electrolyte. Fuel cells according to the present disclosure may include an anode region that is adapted to receive an anode feed stream containing chemically bound hydrogen and which liberates protons at an anode of the fuel cell, a cathode region that is adapted to receive a stream containing oxygen, and an electrolytic barrier that separates the anode and cathode regions and which contains a non-aqueous electrolyte. The non-aqueous electrolyte is preferably acidic or basic. The electrolyte may have an acid ionization constant (Ka) greater than 5×10?6 at 25° C. if the non-aqueous electrolyte is an acid and a base ionization constant (Kb) greater than 5×10?6 at 25° C. if the non-aqueous electrolyte is a base. The fuel cell has an operating temperature of less than 300° C., and may operate at temperatures above, at, and below 100° C.

Abstract: Auxiliary fuel cell system that provides backup power to a primary power source, and energy-consuming systems that are otherwise associated with at least one primary power source and at least one auxiliary fuel cell system. The auxiliary fuel cell system includes at least one fuel cell stack that is adapted to produce an electric current from a fuel and an oxidant, such as from hydrogen and oxygen gases. The auxiliary fuel cell system further includes a source of fuel, such as a source of hydrogen gas, and this source may include a fuel processor that is adapted to produce the hydrogen gas or other fuel. The energy-consuming system is adapted to selectively draw an electric current from a primary power source or an auxiliary fuel cell system. A source selection system selectively establishes electrical communications between an energy-consuming system and the primary power source or the auxiliary fuel cell system.

Abstract: A control system and method for a fuel processing system. The control system automates the operation of a fuel processing system by monitoring operating parameters and automatically controlling the operation of the system responsive to the monitored parameters, predefined subroutines and/or user inputs.

Abstract: An improved feedstock for fuel processing systems, and fuel processing systems incorporating the same. The fuel processing system includes a fuel processor adapted to produce a product hydrogen stream from a carbon-containing feedstock. The fuel processing system may also include a fuel cell stack adapted to produce an electric current from the product hydrogen stream. The feedstock is at least substantially formed of a hydrocarbon or alcohol. In an exemplary embodiment, the feedstock includes methanol. The feedstock also includes at least one odorant adapted to produce a strong and characteristic odor, even when present in only low concentrations. The odorant, or odorants, are selected to be free or at least sufficiently free from compounds that will poison the catalyst used in the fuel processor.

Abstract: Hydrogen-producing fuel processing systems, hydrogen purification membranes, hydrogen purification devices, and fuel processing and fuel cell systems that include hydrogen purification devices. In some embodiments, the fuel processing systems and the hydrogen purification membranes include a metal membrane, which is at least substantially comprised of palladium or a palladium alloy. In some embodiments, the membrane contains trace amounts of carbon, silicon, and/or oxygen. In some embodiments, the membranes form part of a hydrogen purification device that includes an enclosure containing a separation assembly, which is adapted to receive a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. In some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processor, and in some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processing or fuel cell system.

Abstract: A layered bipolar plate assembly and fuel cell stacks and fuel cell systems incorporating the same. In some embodiments, the bipolar plate assembly includes a structural metal that provides strength to the assembly and a conductive metal that provides favorable electrical conductivity. In some embodiments, the structural metal is diffusion bonded to the conductive metal to decrease the electrical resistance between the structural metal and the conductive metal. A flow field established on the surface of the bipolar plate assembly is present in some embodiments. The flow field may be established by sacrificially etching the conductive metal with an etchant configured to etch the conductive metal while leaving the structural metal at most substantially unetched. Methods for forming the bipolar plate assemblies and fuel cell systems including fuel cell stacks with the bipolar plate assemblies are also disclosed.

Abstract: A fuel processing assembly adapted to produce hydrogen gas from a volatile feedstock. The fuel processing assembly includes a fuel processor, such as a steam reformer. The fuel processing assembly further includes a feed assembly adapted to deliver a volatile feedstock, such as propane, to the fuel processor. In some embodiments, the fuel processing system includes a fuel cell stack that includes at least one fuel cell adapted to produce electrical power from hydrogen gas produced by the fuel processor.

Abstract: Methanol steam reforming catalysts, and steam reformers and fuel cell systems incorporating the same. In some embodiments, the methanol steam reforming catalyst includes zinc oxide as an active component. In some embodiments, the methanol steam reforming catalyst further includes at least one of chromium oxide and calcium aluminate. In some embodiments, the methanol steam reforming catalyst is not pyrophoric. Similarly, in some embodiments, steam reformers including a reforming catalyst according to the present disclosure may include an air-permeable or air-accessible reforming catalyst bed. In some embodiments, the methanol steam reforming catalyst is not reduced during use. In some embodiments, the methanol reforming catalysts are not active at temperatures below 275° C. In some embodiments, the methanol steam reforming catalyst includes a sulfur-absorbent material. Steam reformers, reforming systems, fuel cell systems and methods of using the reforming catalysts are also disclosed.

Abstract: Membrane modules that contain one or more hydrogen-selective membranes, methods for preparing the same, and hydrogen purification systems, fuel processors and devices containing the same. In some embodiments, the membrane modules include one or more hydrogen-selective membranes supported on a support or screen structure, of which a variety of embodiments are disclosed. In some embodiments, the membrane or membranes are at least substantially formed from an alloy comprising palladium and copper. In some embodiments, the membranes further include a material having a composition different than the alloy. In some embodiments, the at least one membrane is adhesively mounted on the screen structure during assembly.

Abstract: Hydrogen purification membranes, hydrogen purification devices, and fuel processing and fuel cell systems that include hydrogen purification devices. The hydrogen purification membranes include a metal membrane, which is at least substantially comprised of palladium or a palladium alloy. In some embodiments, the membrane contains trace amounts of carbon, silicon, and/or oxygen. In some embodiments, the membranes form part of a hydrogen purification device that includes an enclosure containing a separation assembly, which is adapted to receive a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. In some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processor, and in some embodiments, the membrane(s) and/or purification device forms a portion of a fuel processing or fuel cell system.

Abstract: A system and method for preventing damage to a fuel cell stack resulting from impurities in the product stream from a fuel processor, such as may occur should the separation region of the fuel processor fail. The system and method include detecting the concentration of at least one component of the product stream and isolating the fuel cell stack should this concentration exceed an acceptable threshold level. In some embodiments, the system or method are adapted to detect the concentration of a component that itself is not harmful to the fuel cell stack, or which is not harmful in an associated threshold concentration. In some embodiments, the detected composition is at least one of water, methane, and carbon dioxide.

Abstract: A fuel processing assembly adapted to produce hydrogen gas from a carbon-containing feedstock. The fuel processing assembly includes a fuel processor, such as a steam reformer. The fuel processing assembly further includes a feed assembly adapted to deliver a carbon-containing feedstock, such as a hydrocarbon, to the fuel processor. In some embodiments, the fuel processing system includes a fuel cell stack that includes at least one fuel cell adapted to produce electrical power from hydrogen gas produced by the fuel processor.

Abstract: The invented system includes a fuel-cell system comprising a fuel cell that produces electrical power from air (oxygen) and hydrogen, and a fuel processor that produces hydrogen from a variety of feedstocks. One such fuel processor is a steam reformer which produces purified hydrogen from a carbon-containing feedstock and water. In the invented system, various mechanisms for implementing the cold start-up of the fuel processor are disclosed, as well as mechanisms for optimizing and/or harvesting the heat and water requirements of the system and/or maintaining the purity of the process water used in the system.

Abstract: A fuel cell system that includes a control system for regulating the power produced by the fuel cell system. The fuel cell system includes a fuel cell stack adapted to produce electrical power from a feed. In some embodiments, the fuel cell system includes a fuel processing assembly adapted to produce the feed for the fuel cell stack from one or more feedstocks. The control system regulates the power produced by the fuel cell system to prevent damage to, and/or failure of, the system.

Abstract: Hydrogen purification devices, components thereof, and fuel processors and fuel cell system containing the same. The hydrogen purification devices include an enclosure that contains a separation assembly adapted to receive a mixed gas stream containing hydrogen gas and to produce a stream that contains pure or at least substantially pure hydrogen gas therefrom. The separation assembly includes at least one hydrogen-permeable and/or hydrogen-selective membrane. The device components that are formed from materials having similar or the same coefficients of thermal expansion as the at least one membrane and/or which are formed from an alloy comprising nickel and copper. In some embodiments, these components include at least a portion of a support for the at least one membrane, and in some embodiments, these components include at least a portion of the enclosure.

Abstract: A feedstock mixing apparatus for fuel processing systems, and fuel processing and fuel cell systems incorporating the same. A fuel processing system according to the present invention includes one or more fuel processors adapted to produce a product hydrogen stream from a feed stream containing water and a carbon-containing feedstock. The fuel processing system further includes a feedstock delivery system adapted to mix the components of the feed stream at a determined mix ratio and to deliver this feed stream to the fuel processor(s). The fuel processing system may also include one or more fuel cell stacks that are adapted to produce an electric current from the product hydrogen stream produced by the fuel processing system. When the fuel processing system includes at least one fuel cell stack, it may be referred to as a fuel cell system.