Abstract: Feedstock delivery systems and hydrogen-producing fuel processing assemblies and fuel cell systems containing the same. The feedstock delivery systems include a liquid pump that draws at least one liquid feedstock from a supply and delivers at least one feed stream containing the feedstock(s) to a fuel processor, such as to the hydrogen-producing region thereof. The feedstock delivery system further includes a recycle conduit that establishes a fluid flow path for the liquid feedstock(s) from a location downstream of the pump back to a location upstream of the pump. In some embodiments, the feedstock delivery system further includes a flow restrictor associated with the recycle conduit and a pressure-actuated valve that selectively permits the recycled feedstock to bypass the flow restrictor. In some embodiments, the pump is configured to draw a greater flow rate of the feed stream from the supply than is delivered to the fuel processor.

Abstract: Improved feedstocks for hydrogen-producing fuel processing and fuel cell systems, and fuel processing and fuel cell systems incorporating the same. The fuel processing systems include a fuel processor adapted to produce a product hydrogen stream from at least one feed stream containing at least a carbon-containing feedstock and an aversive agent. The fuel processing systems 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 some instances the feedstock includes methanol and the aversive agent is delivered to a hydrogen-producing region of the fuel processor with the carbon containing feedstock. The aversive agent can include at least one odorant, flavorants regurgitant, and/or dye. In other instances, the feed stream includes water or the feed stream is delivered to a fuel stack that produces and electric current therefrom.

Abstract: Combustion-based heating assemblies and hydrogen-producing fuel processing assemblies that include at least a reforming region adapted to be heated by the heating assemblies. The heating assembly may include at least one fuel chamber and at least one heating and ignition source. The at least one fuel chamber may be adapted to receive at least one fuel stream at a first temperature. The fuel stream may include a liquid, combustible, carbon-containing fuel having an ignition temperature greater than the first temperature at which the fuel stream is delivered to the fuel chamber. The at least one heating and ignition source may be adapted to heat at least a portion of the fuel chamber to raise the temperature of at least a portion of the carbon-containing fuel to a second temperature at least as great as the ignition temperature and to ignite the carbon-containing fuel. Methods of use are also disclosed.

Abstract: Feedstock delivery systems and hydrogen-producing fuel processing assemblies and fuel cell systems containing the same. The feedstock delivery systems include a liquid pump that draws at least one liquid feedstock from a supply and delivers at least one feed stream containing the feedstock(s) to a fuel processor, such as to the hydrogen-producing region thereof. The feedstock delivery system further includes a recycle conduit that establishes a fluid flow path for the liquid feedstock(s) from a location downstream of the pump back to a location upstream of the pump. In some embodiments, the feedstock delivery system further includes a flow restrictor associated with the recycle conduit and a pressure-actuated valve that selectively permits the recycled feedstock to bypass the flow restrictor. In some embodiments, the pump is configured to draw a greater flow rate of the feed stream from the supply than is delivered to the fuel processor.

Abstract: Systems and methods for producing hydrogen gas with a fuel processing system that includes a hydrogen-producing region that produces hydrogen gas from a feed stream and a heating assembly that consumes a fuel stream to produce a heated exhaust stream for heating the hydrogen-producing region. In some embodiments, the heating assembly heats the hydrogen-producing region to at least a minimum hydrogen-producing temperature. In some embodiments, the rate at which an air stream is delivered to the heating assembly is controlled to selectively increase or decrease the temperature of the heated exhaust stream. In some embodiments, the feed stream and the fuel stream both contain a carbon-containing feedstock and at least 25 wt % water. In some embodiments, the feed and fuel streams have the same composition.

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: Hydrogen-producing fuel processing systems, hydrogen purification membranes, hydrogen purification devices, fuel processing and fuel cell systems that include hydrogen purification devices, and methods for operating the same. In some embodiments, operation of the fuel processing system is initiated by heating at least the reforming region of the fuel processing system to at least a selected hydrogen-producing operating temperature. In some embodiments, an electric heater is utilized to perform this initial heating. In some embodiments, use of the electric heater is discontinued after startup, and a burner or other combustion-based heating assembly combusts a fuel to heat at least the hydrogen producing region, such as due to the reforming region utilizing an endothermic catalytic reaction to produce hydrogen gas.

Abstract: Systems and methods for recovering thermal energy from a fuel processing system comprising a fuel processor and a fuel cell stack in communication with a household that is adapted to apply at least electrical loads, and optionally electrical and thermal loads, to the fuel processing system. The systems further include a thermal energy recovery system that is adapted to recover thermal energy from the fuel processing system and which includes a plurality of thermal energy reservoirs. The recovery system includes a delivery system that is adapted to selectively deliver heat exchange fluid from at least one of the plurality of thermal energy reservoirs into thermal communication with the fuel processing system to recover thermal energy therefrom. In some embodiments, at least one of the thermal energy reservoirs forms at least a portion of a potable hot water supply for the household.

Abstract: Feedstock delivery systems for hydrogen generation assemblies having a hydrogen-producing region and a heating assembly. The delivery system provides a hydrogen-production fluid to the hydrogen-producing region and provides a heating fuel to the heating assembly. The delivery system includes a pressure vessel having an interior cavity containing the heating fuel and the hydrogen-production fluid, which are disposed in the pressure vessel in a pressurizing—pressurized relationship, in which the heating fuel is discharged from the pressure vessel under it own pressure and the hydrogen-production fluid is discharged under pressure applied by the heating fuel. The feedstock delivery system may separately discharge the hydrogen-production fluid and the heating fuel and may include a pressure transmitter disposed between the hydrogen-production fluid and the heating fuel.

Abstract: Systems and methods for producing hydrogen gas with a fuel processing system that includes a hydrogen-producing region that produces hydrogen gas from a feed stream and a heating assembly that consumes a fuel stream to produce a heated exhaust stream for heating the hydrogen-producing region. In some embodiments, the heating assembly heats the hydrogen-producing region to at least a minimum hydrogen-producing temperature. In some embodiments, the feed stream and the fuel stream both contain a carbon-containing feedstock and at least 25 wt % water. In some embodiments, at least one of the feed and fuel streams contain at least one additional component. In some embodiments, the feed and fuel streams have the same composition. In some embodiments, the feed and fuel streams are drawn or obtained from a common source or supply, and in some embodiments as a liquid stream that is selectively apportioned to form the feed and fuel streams.

Abstract: Fuel processing and fuel cell systems with feedstock delivery systems that are designed to deliver a mixed component feed stream to a hydrogen-producing region for the production of hydrogen gas therefrom and to selectively deliver the feed stream to a heating assembly for use as a combustible fuel stream for heating at least the hydrogen-producing region. The feed stream contains water and a carbon-containing feedstock, and may contain at least 31 vol % water. In some embodiments, the feedstock delivery system may be 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.

Abstract: Feedstock delivery systems and hydrogen-producing fuel processing assemblies and fuel cell systems containing the same. The feedstock delivery systems include a liquid pump that draws at least one liquid feedstock from a supply and delivers at least one feed stream containing the feedstock(s) to a fuel processor, such as to the hydrogen-producing region thereof. The feedstock delivery system further includes a recycle conduit that establishes a fluid flow path for the liquid feedstock(s) from a location downstream of the pump back to a location upstream of the pump. In some embodiments, the feedstock delivery system further includes a flow restrictor associated with the recycle conduit and a pressure-actuated valve that selectively permits the recycled feedstock to bypass the flow restrictor. In some embodiments, the pump is configured to draw a greater flow rate of the feed stream from the supply than is delivered to 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 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: 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 distributed fuel cell network and communication systems and subassemblies for use therein. The network includes at least one, and typically a plurality of, fuel cell systems. Each fuel cell system includes a fuel cell stack that is adapted to produce an electric current from oxygen and a source of protons, such as hydrogen gas. The fuel cell systems further include communication subsystems that enable remote monitoring and/or control of the fuel cell systems from a remotely located servicing system, which includes a corresponding communication subsystem. The remotely located servicing system is adapted to monitor and/or control the operation of the fuel cell systems and in some embodiments may include a redundancy of remote servicing units. In some embodiments, the fuel cell systems also include local controllers, while in other embodiments the fuel cell systems do not include local controllers.

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.