Abstract: A bipolar plate comprising a fluid barrier and a sealing frame formed around and overlaping the perimeter of the fluid barrier. The fluid barrier is placed in a mold and then a polymer is injected into the mold, thereby forming the sealing frame around the fluid barrier such that the sealing frame overlaps the perimeter of the fluid barrier. Because there are no surfaces to seal between the perimeter of the fluid barrier and the sealing frame, gaskets or other sealing surfaces are not required. A bipolar plate is further provided comprising a fluid barrier having the perimeter of the fluid barrier between a preformed cathode sealing frame and an anode sealing frame. The anode and cathode sealing frames are adapted to receive an overlapped portion of the perimeter of the fluid barrier. The anode and cathode sealing frames are then bonded together to form a fluid tight seal.

Abstract: Fuel cell emergency power systems comprising a fuel cell having an anode and a cathode, a power distribution unit for selectively directing electrical current from the fuel cell to one or more consuming device, a hydrogen gas control system and an oxygen gas control system. The hydrogen gas control system includes a pressurized hydrogen tank providing hydrogen gas in selective fluid communication to the anode, a hydrogen gas-liquid water phase separator in downstream fluid communication with the anode, and a hydrogen recirculation pump for recirculating substantially liquid water-free hydrogen from the hydrogen gas-liquid water phase separator to the anode.

Abstract: An apparatus and method apply water to a hydrogen-containing composition, such as a hydride, in the presence of a catalyst that promotes hydrolysis to generate hydrogen in a controlled manner. The amount of catalyst used can be carefully tailored so that the reaction rate is limited by the amount of catalyst present (passive control) or it can be sufficiently large so that the reaction is controlled by the rate of water addition (active control).

Abstract: An apparatus and method apply water to a hydrogen-containing composition, such as a hydride, in the presence of a catalyst that promotes hydrolysis to generate hydrogen in a controlled manner. The amount of catalyst used can be carefully tailored so that the reaction rate is limited by the amount of catalyst present (passive control) or it can be sufficiently large so that the reaction is controlled by the rate of water addition (active control).

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: Electrochemical apparatus and methods that support periodic, non-steady state, or discontinuous operation without suffering degradation of materials or loss of efficiency. The invention provides a means for positioning one or more electrodes into contact with electrolyte and means for retracting the one or more electrodes out of contact with the electrolyte. The means for positioning and means for retracting may be the same device or different devices. The means for positioning and means for retracting may be designed to provide automatic, passive, or fail-safe retraction of the electrode upon a given shutdown condition, such as a voltage of less than one Volt being applied between the first and second electrodes, expiration of a time period, an ozone concentration greater than a setpoint ozone concentration, contact pressure of less than 5 psig, and combinations thereof.

Abstract: Apparatus and method for cleaning air. An air cleaner includes a housing that defines an airflow pathway and a catalytic reactor having a catalyst secured on a porous substrate that is disposed transverse to the airflow pathway. Preferably, the catalyst includes a light activated oxidizing photocatalyst or a thermally activated oxidizing catalyst. A photocatalytic reactor will include a light source directed at a light activated oxidizing photocatalyst, such as TiO2 particles or a binary oxide particle species, which is disposed on the porous substrate. Most preferably, a metal catalyst is disposed on the photocatalyst particles at a concentration or loading between about 0.01 wt % and about 5 wt %. The air cleaner may further comprise an adsorption matrix upstream of the catalytic reactor, optionally in combination with a heater. A particulate filter and/or an electrostatic precipitator may also be disposed upstream of the adsorption matrix and the catalytic reactor.

Abstract: Electrochemical apparatus and methods that support periodic, non-steady state, or discontinuous operation without suffering degradation of materials or loss of efficiency. The invention provides a means for positioning one or more electrodes into contact with electrolyte and means for retracting the one or more electrodes out of contact with the electrolyte. The means for positioning and means for retracting may be the same device or different devices. The means for positioning and means for retracting may be designed to provide automatic, passive, or fail-safe retraction of the electrode upon a given shutdown condition, such as a voltage of less than one Volt being applied between the first and second electrodes, expiration of a time period, an ozone concentration greater than a setpoint ozone concentration, contact pressure of less than 5 psig, and combinations thereof.

Abstract: A method for the anodic electrochemical synthesis of ammonia gas. The method comprises providing an electrolyte between an anode and a cathode, providing nitrogen and hydrogen gases to the cathode, oxidizing negatively charged nitrogen-containing species and negatively charged hydrogen-containing species present in the electrolyte at the anode to form adsorbed nitrogen species and adsorbed hydrogen species, respectively, and reacting the adsorbed nitrogen species with the adsorbed hydrogen species to form ammonia. Nitrogen and hydrogen gases may be provided through a porous cathode substrate. The negatively charged nitrogen-containing species in the electrolyte may be produced by reducing nitrogen gas at the cathode and/or by supplying a nitrogen-containing salt, such as lithium nitride, into the molten salt electrolyte.

Abstract: A bipolar assembly for use in electrochemical cell stacks, especially stacks operated at low pressure. The bipolar assembly is lightweight and provides a “post-type” flow field that operates with a low pressure drop. The bipolar assembly comprises a gas barrier having an array of electronically conducting posts disposed approximately perpendicular to the gas barrier. Each end of the posts is in electrical communication with the surface of an electrode. Because the bipolar assembly separates a cathode from an anode, the posts contact an anode electrode on one end and a cathode electrode on the other end. The posts provide current conduction through the stack as well as provide the flow fields for the electrochemical reactants. Optionally, the bipolar assembly may contain cooling fluid channels formed by adding additional gas barriers to the bipolar assembly. The space between the gas barriers form a channel through which cooling fluids may be circulated.

Abstract: This invention is an improved fuel cell design for use at low pressure. The invention has a reduced number of component parts to reduce fabrication costs, as well as a simpler design that permits the size of the system to be reduced at the same time as performance is being improved. In the present design, an adjacent anode and cathode pair are fabricated using a common conductive element, with that conductive element serving to conduct the current from one cell to the adjacent one. This produces a small and simple system suitable for operating with gas fuels or alternatively directly with liquid fuels, such as methanol, dimethoxymethane, or trimethoxymethane. The use of these liquid fuels permits the storage of more energy in less volume while at the same time eliminating the need for handling compressed gases which further simplifies the fuel cell system.

Abstract: An electrochemical cell comprising a plurality of electrochemical cell components having at least one opening extending therethrough. At least one filament extends through the at least one opening and has two ends with first and second securing members coupled to the two ends. A biasing member is disposed to put the at least one filament in tension between the securing members and to put the plurality of electrochemical cell components in compression. The filament is preferably electronically insulating and preferably does not transmit torsional forces. The filament extends through the at least one opening at least one time and may loop around a securing member any number of times. The filament may have a finite cut length or may form a continuous filament loop.

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: The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The system may be configured to operate passively with no moving parts or in a self-pressurizing manner with the inclusion of a pressure controlling device or valve in the gas outlet of the anode reservoir. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Abstract: A method for electrochemical synthesis of ammonia gas comprising providing an electrolyte between an anode and a cathode, providing hydrogen gas to the anode, oxidizing negatively charged nitrogen-containing species present in the electrolyte at the anode to form an adsorbed nitrogen species, and reacting the hydrogen with the adsorbed nitrogen species to form ammonia. Preferably, the hydrogen gas is provided to the anode by passing the hydrogen gas through a porous anode substrate. It is also preferred to produce the negatively charged nitrogen-containing species in the electrolyte by reducing nitrogen gas at the cathode. However, the negatively charged nitrogen-containing species may also be provided by supplying a nitrogen-containing salt, such as lithium nitride, into the molten salt electrolyte mixture in a sufficient amount to provide some or all of the nitrogen consumed in the production of ammonia.

Abstract: A method for securing an anode, a cathode and an ion exchange membrane disposed between the anode and the cathode within a premolded thermoplastic frame. The frame both secures the anode the cathode and the ion exchange membrane within the frame and further maintain the anode, cathode and membrane in intimate contact. Additionally, injection molding around the premolded thermoplastic frame may be performed or alternatively, injection molding around a plurality of thermoplastic frames.

Abstract: Electrochemical apparatus and methods that support periodic, non-steady state, or discontinuous operation without suffering degradation of materials or loss of efficiency. The invention provides a means for positioning one or more electrodes into contact with electrolyte and means for retracting the one or more electrodes out of contact with the electrolyte. The means for positioning and means for retracting may be the same device or different devices. The means for positioning and means for retracting may be designed to provide automatic, passive, or fail-safe retraction of the electrode upon a given shutdown condition, such as a voltage of less than one Volt being applied between the first and second electrodes, expiration of a time period, an ozone concentration greater than a setpoint ozone concentration, contact pressure of less than 5 psig, and combinations thereof.

Abstract: This invention is an improved fuel cell design for use at low pressure. The invention has a reduced number of component parts to reduce fabrication costs, as well as a simpler design that permits the size of the system to be reduced at the same time as performance is being improved. In the present design, an adjacent anode and cathode pair are fabricated using a common conductive element, with that conductive element serving to conduct the current from one cell to the adjacent one. This produces a small and simple system suitable for operating with gas fuels or alternatively directly with liquid fuels, such as methanol, dimethoxymethane, or trimethoxymethane. The use of these liquid fuels permits the storage of more energy in less volume while at the same time eliminating the need for handling compressed gases which further simplifies the fuel cell system.

Abstract: The present invention relates to an oxygen electrode for a unitized regenerative hydrogen-oxygen fuel cell and the unitized regenerative fuel cell having the oxygen electrode. The oxygen electrode contains components electrocatalytically active for the evolution of oxygen from water and the reduction of oxygen to water, and has a structure that supports the flow of both water and gases between the catalytically active surface and a flow field or electrode chamber for bulk flow of the fluids. The electrode has an electrocatalyst layer and a diffusion backing layer interspersed with hydrophilic and hydrophobic regions. The diffusion backing layer consists of a metal core having gas diffusion structures bonded to the metal core.

Abstract: An apparatus for treating an exhaust gas stream from cold startup through continuous operating conditions of an internal combustion engine includes an oxidizing catalyst bed disposed in an exhaust pipe and a reducing catalyst bed disposed in the exhaust pipe downstream from the oxidizing catalyst bed. The oxidizing catalyst bed as one or more oxidizing catalysts and the reducing catalyst bed has one or more reducing catalysts. A method is provided for treating an exhaust gas stream both during cold start and during continuous operating conditions of an internal combustion engine by passing the stream through an oxidizing catalyst bed having one or more oxidizing catalysts at a light off temperature; a reducing catalyst bed having one or more reducing catalysts and providing hydrogen into the reducing catalyst bed to condition the reducing catalyst; and introducing hydrogen into the internal combustion engine during cold startup.