Abstract: A direct antifreeze cooled fuel cell is disclosed for producing electrical energy from reducing and process oxidant fluid streams that includes an electrolyte secured between an anode catalyst and a cathode catalyst; a porous anode substrate secured in direct fluid communication with and supporting the anode catalyst; a porous wetproofed cathode substrate secured in direct fluid communication with and supporting the cathode catalyst; a porous water transport or cooler plate secured in direct fluid communication with the porous cathode substrate; and, a direct antifreeze solution passing through the porous water transport plate. A preferred direct antifreeze solution passing through the porous water transport plate remains essentially within the water transport plate and does not poison the catalysts.

Abstract: An integrated manifold system for a fuel cell power plant includes a first fuel cell stack and a second fuel cell stack, wherein a common manifold is adapted to be in fluid communication with the first fuel cell stack and the second fuel cell stack. The common manifold includes a first plenum for diverting a first reactant to each of the first and second fuel cell stacks, and a second plenum for accepting the first reactant as the first reactant is exhausted from each of the first and second fuel cell stacks.

Abstract: The invention is an operating system for a fuel cell power plant that includes at least one fuel cell for producing electrical energy from a reducing and oxidant fluid and fuel processing components including a reformer and a burner for processing a hydrocarbon fuel into the reducing fluid, and a direct mass and heat transfer device secured in fluid communication with both a process oxidant stream and a plant exhaust passage, so that the device directly transfers mass such as water exiting the plant in a plant exhaust stream back into the plant within the process oxidant stream. The invention also includes a split oxidant passage that directs the process oxidant stream through the fuel cell and a reformer feed portion of the process oxidant stream into fluid communication with the fuel processing components.

Abstract: The invention is a humidification system for a fuel cell power plant. The system includes at least one fuel cell comprising a coolant flow field adjacent the cathode flow field. The coolant flow field includes a coolant inlet, a coolant outlet, and a split-path coolant distribution channel between the coolant inlet and outlet. The split-path distribution channel directs some of the coolest portion of the coolant stream to flow adjacent the cathode inlet and some of the coolest portion to flow adjacent the cathode outlet. The humidification system lowers a temperature of the process oxidant stream adjacent the cathode inlet, thereby increasing relative humidity of the stream in the cathode flow field adjacent the cathode inlet.

Abstract: A direct antifreeze cooled fuel cell is disclosed for producing electrical energy from reducing and process oxidant fluid streams that includes an electrolyte secured between an anode catalyst and a cathode catalyst; a porous anode substrate secured in direct fluid communication with and supporting the anode catalyst; a porous wet proofed cathode substrate secured in direct fluid communication with and supporting the cathode catalyst; a porous water transport plate secured in direct fluid communication with the porous cathode substrate; and, a direct antifreeze solution passing through the porous water transport plate. In operation of the fuel cell, because product water generated electrochemically at the cathode catalyst flows away from the cathode catalyst into the cathode substrate and into the water transport plate and because the cathode substrate is wetproofed, the antifreeze solution passing through the water transport plate remains essentially within this plate.

Abstract: The invention is a water retention system for a fuel cell power plant having at least one fuel cell and a coolant loop with a coolant reservoir and coolant passages for directing a coolant fluid through the fuel cell. An air conditioning unit is provided for directing a refrigerant to a first heat exchanger that cools secondary process air and for directing water condensed from the secondary process air to the coolant reservoir. The air conditioning unit also directs the refrigerant to a second heat exchanger that cools the coolant fluid within the coolant loop, and to a third heat exchanger that cools a plant exhaust stream exiting the plant. Water condensed from the plant exhaust is also directed from the third heat exchanger into the coolant reservoir.

Abstract: A process for regenerating a selective oxidizer bed, by the introduction of oxygen is provided. In a single oxidizer bed environment, regeneration may be carried out on shut-down or on start-up. On start-up, the process includes providing a selective oxidizer bed as well a fuel processor. The selective oxidizer bed is heated to approximately 180° F. Air is passed through the selective oxidizer bed while maintaining the selective oxidizer bed at a temperature of approximately 180° F. for 1-2 minutes. The selective oxidizer is then purged with steam to remove residual air therefrom. Fuel is then introduced from the fuel processor into the selective oxidizer. On shut-down, residual fuel is purged from the oxidizer bed and then air is passed therethrough while maintaining the bed at a temperature between approximately 180° F. to approximately 220° F. The oxidizer is allowed to cool to ambient temperature and then heated to 180° F.

Abstract: A PEM flow field system of coolant medium for preventing the formation and accumulation of gas bubbles, having a critical viscous pressure drop therein is provided. The water transport plate includes a coolant flow field channel therein having an input port and an exit port. The coolant flow field channel includes at least one upward flow channel portion, at least one downward flow channel portion. Coolant medium is fluidly routed through the coolant flow field channel of the water transport plate at a flow rate which results in a viscous pressure drop that is greater than the buoyancy of a gas bubble trapped within the coolant flow field channel to prevent the accumulation thereof within the coolant flow field channel.

Abstract: A fuel cell power plant, generally, has a fuel cell stack for electrochemically converting a hydrocarbon fuel into electricity. In order for the hydrocarbon fuel to be used by the fuel cell stack, it must be steam reformed into a hydrogen-rich process gas. This process gas has a carbon monoxide level that would be detrimental to the fuel cell stack, so the process gas is passed through a shift converter to decrease the carbon monoxide level therein prior to feeding the process gas to the fuel cell stack. In order to decrease the level of carbon monoxide without the need to increase the size of the shift converter catalyst bed, or lower the temperature of the process gas as it enters the shift converter to an undesirably low temperature, the shift converter design that utilizes an upstream adiabatic zone and a downstream actively cooled zone. The actively cooled zone is cooled by a pressurized water coolant which boils as it cools the process gas stream.

Abstract: A compact and efficient fuel reformer which is operable to produce a hydrogen-enriched process fuel from a raw fuel such as natural gas, or the like includes a compact array of catalyst tubes which are contained in a heat-insulated housing. The catalyst tube array preferably includes a multitude of catalyst tubes that are arranged in a hexagonal array. The housing includes internal hexagonal thermal insulation so as to ensure even heating of the catalyst tubes. The diameter of the tubes is sized so that spacing between adjacent tubes in the array can be minimized for efficient heat transfer. The interior of each of the catalyst tubes includes a hollow dead-ended central tube which serves as a fines trap for collecting catalyst fines that may become entrained in the fuel stream. The catalyst tubes are also provided with an upper frusto-conical portion which serves to extend the catalyst bed and provide a catalyst reserve.

Abstract: A process gas selective oxidizer assemblage for use in a fuel cell power plant includes one or more catalyzed selective oxidizer process gas flow fields and one or more adjacent non-catalyzed heat exchanger process gas flow fields. The catalyzed selective oxidizer process gas flow fields may be formed with catalyzed pellets or with a monolithic catalyzed open cell foam component. The heat exchanger process gas flow fields are formed by non-catalyzed monolithic open cell foam components which have coolant fluid passages disposed therein. Planar metal sheets form a common wall between the selective oxidizer process gas flow fields and the heat exchanger process gas flow fields. The use of the open cell foam to form the heat exchanger process gas flow fields provides enhanced heat transfer between the reformate gas and the coolant fluid.

Abstract: Methods and apparatus for improving water management in a PEM fuel cell power supply are disclosed. The fuel cell power supply includes a combustion unit that combusts anode exhaust, producing combusted exhaust that includes water. The combusted exhaust is recycled to the anode input and/or the cathode input. The recycling system can include additional devices, for example, a CO removal device for removing CO from the combusted exhaust prior to recycling to the anode. A fuel processor can be thermally coupled to the combustion unit that combusts the anode exhaust. One advantage of the invention is that the condenser typically employed for recovering water from combusted exhaust can be eliminated, of reduced capacity or operated less frequently, thereby reducing the cost and/or the complexity of the fuel cell power supply.

Abstract: The invention is a hydride bed water recovery system for a fuel cell power plant that has at least one fuel cell having an electrolyte between anode and cathode electrodes for producing an electric current from a reducing fluid and an oxidant stream. A coolant loop directs a coolant fluid from a coolant reservoir through a coolant passage to the fuel cell and back to the reservoir. A process exhaust passage receives a cathode exhaust stream from the fuel cell and directs the stream away from the fuel cell and into a hydride bed cooler that passes the stream in heat exchange relationship with a condensing hydride bed of the cooler so that the bed cools the process exhaust stream to condense water out of the stream.

Abstract: A fine pore enthalpy exchange barrier is disclosed for use with a fuel cell power plant. The barrier includes a support matrix that defines pores and a liquid transfer medium that fills the pores creating a gas barrier. An inlet surface of the fine pore enthalpy exchange barrier is positioned in contact with a process oxidant inlet stream entering a fuel cell power plant, and an opposed exhaust surface of the barrier is positioned in contact with an exhaust stream exiting the plant so that water and heat exchange from the exhaust stream directly into the process oxidant inlet stream to heat and humidify the stream as it enters the plant. The liquid transfer medium may include water, aqueous salt solutions, aqueous acid solutions, or organic antifreeze water solutions.

Abstract: A fuel gas reformer assembly for use in a fuel cell power plant includes fuel gas passages, some of which contain a particulate alumina packing in which a vaporized steam-hydrocarbon fuel stream mixture is heated. The walls of the fuel gas passages are provided with an alumina coating which protects the walls of the passages from corrosion. The alumina coating of the walls, and alumina packing are both overlain by an alkaline earth metal oxide layer, such as a calcium oxide layer, that acts to limit carbon build-up on the surfaces of the coated passage walls. Limiting of carbon build-up in the reformer passages prevents premature clogging of the passages. The carbon build-up-limiting layer is formed on components of the reformer passages by applying a water-based slurry of alkaline earth metal compounds to the reformer passage surfaces, and then drying the slurry so as to solidify it.

Abstract: Solid polymer membrane fuel cell water which collects on the oxidant side of the membrane is removed from the active area of the cells in a fuel cell power plant by being absorbed into porous carbon bodies, one of which contacts the membrane. Some of the treated carbon bodies can also be used to supply water to the anode side of the membrane in order to minimize anode side membrane drying. The pores in the carbon body are partially filled, or coated, with precursors of metal oxyhydroxide compounds, which, when converted, will impart increased wettability and water absorption capacity to the carbon body. Hydroxides of the filler compounds are applied to the carbon body and are heated to convert them into oxyhydroxides. As used in this document, the term “oxyhydroxide” includes oxyhydroxides, oxyhydroxide hydrates, and oxide hydrates. Processing temperatures are low enough so as to not subject the bodies being impregnated to destabilization.

Abstract: An apparatus for the thermal management of an electrochemical fuel cell assembly, wherein a plurality of thermal management loops in contact with the fuel cell assembly are utilized to maintain the fuel cell assembly above freezing or, alternatively, raise the fuel cell assembly above freezing. The thermal management loops are in thermal communication with the fuel cell assembly as well as each other, but are diffusably isolated from one another.

Abstract: A method and apparatus for removing contaminants from the coolant supply of a fuel cell power plant, wherein coolant which has been exhausted from the fuel cell power plant is fed to an oxidant manifold. The exhausted coolant interacts with the oxidant flowing through the oxidant manifold, thereby effectuating removal of contaminants from the exhausted coolant.

Abstract: A gas injection system for treating an electrochemical fuel cell stack assembly, wherein the fuel cell stack assembly is repeatedly injected with an oxidizing gas at critical locations along the fuel path of the fuel cell stack assembly so that the fuel supply and the oxidizing gas will chemically react to reduce at least one harmful contaminant within the fuel supply. The preferred gas injection system treats a fuel cell stack assembly to reduce the debilitating effects of extraneous carbon monoxide within the fuel supply thereby preserving the efficient operation of the fuel cell stack assembly.

Abstract: A dual coolant loop fuel cell power plant is disclosed that includes at least one fuel cell for producing an electric current from a reducing fluid and an oxidant stream, wherein the fuel cell includes an electrolyte secured between an anode catalyst and a cathode catalyst. An anode flow field is defined adjacent the anode catalyst and extends between a reducing fluid inlet and a reducing fluid outlet. A cathode flow field is defined adjacent the cathode catalyst and extends between an oxidant inlet and an oxidant outlet. A reaction zone is defined within the anode and cathode flow fields co-extensive with the anode and cathode catalysts, and a condensation zone is defined extending from the oxidant outlet into the anode and cathode flow fields.