Abstract: A method for controlling multiple voltages in a power supply includes providing a plurality of DC to DC power converters. Each power converter includes a pulse width modulator controller having a control pin. The method also includes when a voltage supply to the power controllers reads a particular level. After the particular level is met, the method includes providing a respective rising ramp control signal to each respective control pin of the pulse width modulator controller such that each respective power converter generates desired voltage level over time characteristics.

Abstract: A subassembly for a stack of electrochemical cells that includes a porous metal sheet having a first face and a second face with a hydrophobic, carbonaceous gas diffusion layer disposed within the pores along the first face of the porous metal sheet. The second face of the porous metal sheet defines a flow field while that portion of the porous metal sheet filled with the gas diffusion layer forms a current collector. The subassembly may further include a metal gas barrier metallurgically bonded to the second face of the porous metal sheet to act as a gas barrier between the porous metal sheet and a second porous metal sheet having a second gas diffusion layer disposed within the pores along a face of the second porous metal sheet. Preferably, the gas diffusion layers are applied as a paste to the porous metal sheet and then dried.

Abstract: A hydrogen-oxygen fuel cell operates with greater safety if a leak develops between the anode and the cathode sides of the fuel cell allowing hydrogen and oxygen to become mixed on whichever side operates at the lower pressure. A recombination catalyst is disposed within the fuel cell to catalyze the recombination reaction of hydrogen and oxygen to form water and prevent the formation of an explosive mixture. The hydrogen-oxygen recombination catalyst is disposed in a hydrogen distribution system, an oxygen distribution system, or a combination thereof. Suitable recombination catalysts include platinum or alloys thereof, palladium, gold, tin, and combinations thereof, with or without platinum. Still other suitable recombination catalysts include, for example, noble metals, nickel-paladium, and nickel oxides.

Abstract: Protecting a membrane and electrode assembly in an electrochemical cell having one or more electrocatalysts in intimate contact with the membrane during storage or shipment of the cell. The membrane may be provided in either the non-proton form of a dry or hydrated cation exchange membrane, such as an alkali metal cation form or an ammonium cation form; the wet or dry precursor form of a cation exchange membrane, such as the non-ionically conducting sulfonyl-fluoride polymer membrane; or the dry proton form of a cation exchange membrane. These membrane surfaces are not acidic under open circuit conditions experienced during storage or shipment of the cell. Since some electrocatalysts are degraded during contact with the acidic surface of a hydrated membrane, the non-acidic surface of the membrane protects these electrocatalysts. The method may be used on newly assembled electrochemical cells, on cells being taken out of service, and on membrane and electrode assemblies.

Abstract: The present invention provides a self-replenishing liquid water source onboard an automobile for supplying liquid water to an electrolyzer, such as an on-board hydrogen generator useful for the suppression of unwanted emissions. While automobiles typically have water reservoirs resupplied by a person, the invention provides a passive means of water collection for reliable replenishment due to operations of the automobile itself. The invention provides condensate from the engine exhaust gas by cooling a region of the exhaust system using cooling fluid from the engine coolant system. The cooling fluid is circulated during a period following the engine cold start event when the heat load on the engine coolant system is low.

Abstract: An apparatus for electrochemical impedance spectroscopy having a solid electrolyte is disclosed. The apparatus has a chamber made of an electronically insulating material, a solid electrolyte coupled to the chamber and an electrode disposed in the chamber. A biasing member is used to urge the electrode towards the solid electrolyte and urge the solid electrolyte toward the substrate. The solid electrolyte is designed to contact the surface to be tested directly with no corrosive or otherwise harmful effect to the surface. A method for the detection of corrosion in bare or coated metallic substrates is also provided.

Abstract: The invention provides for reducing the number of parts and the number of interfaces found in certain types of chemical reactors, particularly in electrochemical reactors, and especially in the type or reactor known as a fuel cell or fuel cell stack. This reduction comes from the use of a unified structure that combines the functions normally carried out by several components in the unit, particularly by combining the functions of the gas distribution structure and the gas diffusion structure, the gas distribution structure and the gas barrier structure, or all three structures into a single, unitary, metallic part. This offers the advantages of simplified design, better performance, and lighter weight.

Abstract: The invention provides for reducing the number of parts and the number of interfaces found in certain types of chemical reactors, particularly in electrochemical reactors, and especially in the type or reactor known as a fuel cell or fuel cell stack This reduction comes from the use of a unified structure that combines the functions normally carried out by several components in the unit, particularly by combining the functions of the gas distribution structure and the gas diffusion structure, the gas distribution structure and the gas barrier structure, or all three structures into a single, unitary, metallic part. This offers the advantages of simplified design, better performance, and lighter weight.

Abstract: The present invention provides a self-replenishing liquid water source onboard an automobile for supplying liquid water to an electrolyzer, such as an on-board hydrogen generator useful for the suppression of unwanted emissions. While automobiles typically have water reservoirs resupplied by a person, the invention provides a passive means of water collection for reliable replenishment due to operations of the automobile itself. The invention provides condensate from the engine exhaust gas by cooling a region of the exhaust system using cooling fluid from the engine coolant system. The cooling fluid is circulated during a period following the engine cold start event when the heat load on the engine coolant system is low.

Abstract: The present invention provides a self-replenishing liquid water source onboard an automobile for supplying liquid water to an electrolyzer, such as an on-board hydrogen generator useful for the suppression of unwanted emissions. While automobiles typically have water reservoirs resupplied by a person, the invention provides a passive means of water collection for reliable replenishment due to operations of the automobile itself. The invention provides condensate from the engine exhaust gas by cooling a region of the exhaust system using cooling fluid from the engine coolant system. The cooling fluid is circulated during a period following the engine cold start event when the heat load on the engine coolant system is low.

Abstract: Thin, light weight bipolar plates for use in electrochemical cells are rapidly, and inexpensively manufactured in mass production by die casting, stamping or other well known methods for fabricating magnesium or aluminum parts. The use of a light metal, such as magnesium or aluminum minimizes weight and simultaneously improves both electrical and thermal conductivity compared to conventional carbon parts. For service in electrochemical cells these components must be protected from corrosion. This is accomplished by plating the surface of the light weight metal parts with a layer of denser, but more noble metal. The protective metal layer is deposited in one of several ways. One of these is deposition from an aqueous solution by either electroless means, electrolytic means, or a combination of the two. Another is deposition by electrolytic means from a non-aqueous solution, such as a molten salt.

Abstract: A method and apparatus for mineralizing organic contaminants in water or air provides photochemical oxidation in a two-phase or three-phase boundary system formed in the pores of a TiO2 membrane in a photocatalytic reactor. In the three-phase system, gaseous (liquid) oxidant, liquid (gaseous) contaminant, and solid semiconductor photocatalyst meet and engage in an efficient oxidation reaction. The porous membrane has pores which have a region wherein the meniscus of the liquid varies from the molecular diameter of water to that of a capillary tube resulting in a diffusion layer that is several orders of magnitude smaller than the closest known reactors. The photocatalytic reactor operates effectively at ambient temperature and low pressures. A packed-bed photoreactor using photocatalyst coated particles is also provided.

Abstract: The present invention provides a self-replenishing liquid water source onboard an automobile for supplying liquid water to an electrolyzer, such as an on-board hydrogen generator useful for the suppression of unwanted emissions. While automobiles typically have water reservoirs resupplied by a person, the invention provides a passive means of water collection for reliable replenishment due to operations of the automobile itself. The invention provides condensate from the engine exhaust gas by cooling a region of the exhaust system using cooling fluid from the engine coolant system. The cooling fluid is circulated during a period following the engine cold start event when the heat load on the engine coolant system is low.

Abstract: The invention provides for reducing the number of parts and the number of interfaces found in certain types of chemical reactors, particularly in electrochemical reactors, and especially in the type or reactor known as a fuel cell or fuel cell stack. This reduction comes from the use of a unified structure that combines the functions normally carried out by several components in the unit, particularly by combining the functions of the gas distribution structure and the gas diffusion structure, the gas distribution structure and the gas barrier structure, or all three structures into a single, unitary, metallic part. This offers the advantages of simplified design, better performance, and lighter weight.

Abstract: Thin, light weight bipolar plates for use in electrochemical cells are rapidly, and inexpensively manufactured in mass production by die casting, stamping or other well known methods for fabricating magnesium or aluminum parts. The use of a light metal, such as magnesium or aluminum minimizes weight and simultaneously improves both electrical and thermal conductivity compared to conventional carbon parts. For service in electrochemical cells these components must be protected from corrosion. This is accomplished by plating the surface of the light weight metal parts with a layer of denser, but more noble metal. The protective metal layer is deposited in one of several ways. One of these is deposition from an aqueous solution by either electroless means, electrolytic means, or a combination of the two. Another is deposition by electrolytic means from a non-aqueous solution, such as a molten salt.

Abstract: A method and apparatus for mineralizing organic contaminants in water or air provides photochemical oxidation in a two-phase or three-phase boundary system formed in the pores of a TiO.sub.2 membrane in a photocatalytic reactor. In the three-phase system, gaseous (liquid) oxidant, liquid (gaseous) contaminant, and solid semiconductor photocatalyst meet and engage in an efficient oxidation reaction. The porous membrane has pores which have a region wherein the meniscus of the liquid varies from the molecular diameter of water to that of a capillary tube resulting in a diffusion layer that is several orders of magnitude smaller than the closest known reactors. The photocatalytic reactor operates effectively at ambient temperature and low pressures. A packed-bed photoreactor using photocatalyst coated particles is also provided.

Abstract: A method and apparatus for mineralizing organic contaminants in water or air provides photochemical oxidation in a unique two-phase or three-phase boundary system formed in each pore of a TiO.sub.2 membrane in a photocatalytic reactor. In the three-phase system, gaseous oxidant, liquid contaminant, and solid semiconductor photocatalyst having a metal catalyst disposed thereon meet and engage in an efficient oxidation reaction. The porous membrane has pores which have a region wherein the meniscus of the liquid varies from the molecular diameter of water to that of a capillary tube resulting in a diffusion layer that is several orders of magnitude smaller than the closest known reactors. The photocatalytic reactor operates effectively at ambient temperature and low pressures.

Abstract: The present invention provides an apparatus and method for assembling an electrochemical cell stack, or an assemblage of components which need to be clamped together, especially where minimizing the size and weight of the clamping mechanism is advantageous. The invention encompasses combining a band or strap to transmit load to a plurality of components. A metal link is provided to apply greater tension to the band than could normally be achieved with the band alone. The invention may provide a band having a spiral screw clamp wherein the screw portion is used to apply and control tension in the band and the band is used to transmit the tension to a plurality of components. The invention also provides systems that improve the distribution of the force over a portion of the assembly, preferably the entire area of at least one face of the assembly.

Abstract: The invention provides devices and techniques for reducing or eliminating fuel crossover from the anode to the cathode in fuel cells using organic fuels. The invention particularly provides proton exchange membranes having passages or channels with or without a catalyst layer active for the electrochemical oxidation of a fuel. The invention reduces fuel crossover by providing void spaces within the membrane where the fuel may be sequestered as it diffuses through the membrane from the anode to the cathode. The sequestered fuel may be removed physically and/or electrochemically. The invention provides for physical removal of the sequestered fuel by means of flowing a gas stream or a liquid stream through the passages thus evacuating the fuel before it diffuses to the cathode.