Abstract: A technique for rejecting heat from a fuel cell stack. Heated stack coolant from the fuel cell stack is directed to a heat pump module where it is compressed to raise its temperature. The heated and compressed coolant is then directed through a radiator that cools the coolant through interaction with ambient air. The coolant is then sent through an expansion aperture to reduce its pressure, and thus, further reduce its temperature before it is sent back to the fuel cell stack to collect waste heat therefrom. The heated and compressed coolant can be sent to hydride bed to release hydrogen therefrom before it is sent to the radiator. In one embodiment, the coolant is hydrogen.

Abstract: Flow-field for a PEM fuel cell having a plurality of flow-channels including flow-restrictors strategically located throughout to achieve desired pressure differentials between fuel and oxidant supply and exhaust manifolds, and between adjacent flow-channels. A preferred flow-restrictor comprises a constriction in the flow channel that has a cross-sectional area that is less than the cross-sectional area of the flow-channel.

Abstract: A system for detecting an isolation fault in a multi-stack fuel cell system. The system determines the percentage of the voltage from each stack in the multi-stack that contributes to the voltage at a positive terminal and a negative terminal of the stack when a no-fault condition exists. The system then uses those percentages and the actual measured stack voltages to determine if a fault condition exists. The actual voltage measurement at the positive terminal is compared to the calculated voltage contribution from each stack at the positive terminal for the no-fault condition. Also, the actual voltage measurement at the negative terminal is compared to the calculated voltage contribution from each, stack at the negative terminal for the no-fault condition. If there is a significant enough different between the calculated voltage for a no-fault condition and the calculated percentage of the actual voltage measurements, than a fault condition exists.

Abstract: A reaction vessel that integrates and balances an endothermic process with at least one exothermic process of the fuel cell system. Preferably the exothermic process is conducted in stages to provide more uniform and/or controllable heat generation and exchange, and to produce a uniform and/or controllable temperature profile in the endothermic reaction process. The invention allows for the elimination of the working fluid loop of prior art systems that had unsatisfactory response times at startup, and during transient conditions, and also added to the overall mass and volume of the fuel cell system.

Abstract: A system for reducing the time that it takes a vehicle fuel cell engine to reach its operating temperature at vehicle start-up. The system includes a radiator and a fan, where a cooling fluid from the engine is directed through the radiator where it is cooled by airflow from the fan during high load conditions. The radiator also receives ambient air through a front grill from movement of the vehicle. During vehicle start-up, when the engine is below its optimal operating temperature, the fan is operated in a reverse direction at variable speeds depending on the speed of the vehicle, so that the airflow through the grill that may otherwise convectively cool the engine is significantly reduced or eliminated.

Abstract: A fuel cell system and process using an organic Rankine cycle to produce shaft work to operate a fuel cell system component such as an air compressor. The air compressor delivers compressed air to a fuel cell stack. The steps of the Rankine cycle include pumping a liquid working fluid to an elevated pressure, heating the fluid to a gas, expanding the high temperature and high-pressure gas through an expander to produce shaft work used to drive a fuel cell system component such as an air compressor, and then removing energy from the cooling fluid to change the gas back to a liquid, and repeating the cycle. The liquid fluid can be heated by an external boiler, or one of the components of the fuel cell system such as the combustor and/or the fuel cell stack.

Abstract: A delivery system for the delivery of a gaseous fuel such as for example hydrogen, to a consumer, in particular to a fuel cell stack, wherein the fuel comes from a source with a higher pressure level, the delivery system comprising at least one mechanical pressure regulating valve which has a valve member biased by means of a spring and which is designed to regulate the fuel from the higher pressure level down to a lower pressure level which serves as the feed pressure for a control valve, wherein the control valve is connectable via a feed line to a consumer and determines the mass flow of the fuel coming from the source which is supplied to the consumer and wherein changes of the pressure prevailing at the consumer side of the control valve arise with power changes of the consumer, is characterized in that the said pressure prevailing at the consumer side of the control valve, or a value proportional to the latter or corresponding to it, can be supplied via a control line to the mechanical pressure regulati

Abstract: A process including topically applying a finely divided powder onto a plurality of polystyrene beads. The finely divided powder includes brominated compounds including a brominated alkane having at least one substituent aromatic group. The polystyrene beads are pre-expanded with the topically applied brominated compounds and a molded pattern is formed from the pre-expanded polystyrene beads. A lost foam casting mold is formed with the molded pattern. Molten metal is poured into the lost foam casting mold and onto the molded pattern to depolymerize the polystyrene beads with the topically applied brominated compounds.

Abstract: A thermal management system of an electrochemical engine comprises a radiator provided with a wicking mechanism, a coolant pump fluidly connected to the radiator, a water tank, and a water pump. The water tank is located in the void spaces around fuel storage tanks, and may be filled directly or with reclaimed water from a vapor by-product of the electrochemical engine. The water pump is operable to supply water from the water tank to the wicking mechanism during peak power and/or hot day conditions. Moisture in the vapor by-product may be condensed with the excess cooling capacity of the radiator under less severe cooling conditions. Under freezing conditions, exhaust or coolant from the electrochemical engine may be used to unfreeze water in the tank and wicking mechanism supply lines.

Abstract: A PSA unit for purifying hydrogen in a fuel processor system. The PSA unit employs rotary valves that cycle the pressurization of vessels, including an adsorbent, between a high pressure state and a low pressure state. The purified hydrogen is released from the vessels through a purified gas output port when the vessels are in the high pressure state and the impurities are released through an exhaust port when the vessels are in the low pressure state. The PSA unit also employs a mass flow control device and a pressure sensor in the purified gas output port. A controller receives a pressure signal from the pressure sensor, and controls the flow through the mass flow control device and the speed of the rotary valves so that the proper pressure is maintained at the hydrogen output port.

Abstract: A fuel cell system including a fuel reforming processor having a catalyst therein constructed and arranged to produce a reformate stream including hydrogen and carbon monoxide, a water gas shift reactor downstream of the fuel reforming processor and wherein the water gas shift reactor includes a catalyst therein constructed and arranged to reduce the amount of carbon monoxide in the reformate stream, a preferential oxidation reactor downstream of the water gas shift reactor and wherein the preferential oxidation reactor includes a catalyst therein constructed and arranged to preferentially oxidize carbon monoxide into carbon dioxide and to produce a hydrogen-rich stream, and a fuel cell stack downstream of the preferential oxidation reactor constructed and arranged to produce electricity from the hydrogen-rich stream, a first direct water vaporizing combustor constructed and arranged to combust fuel producing a high-temperature fuel combustion byproducts exhaust and to produce steam from water sprayed into th

Abstract: A fuel cell generation system employing a load following algorithm that provides the desired output power from the fuel cell on demand. The system includes a draw current sensor that measures the current drawn from the fuel cell used to satisfy the system load demands. The load following algorithm uses the measured draw current to identify the proper amount of fuel and air to meet the load demands, and then provides a buffer of extra fuel and air to the fuel cell so if the load demand suddenly increases, the fuel cell is able to immediately produce the extra output power. As the current drawn from the fuel cell changes in response to changing load demands, the load following algorithm causes the amount of fuel and air being applied to the fuel cell stack to increase and decrease so that the buffer of extra fuel and air is maintained substantially constant.

Abstract: The present invention provides a method of operating a fuel cell system and a fuel cell system that can adjust the operating pressure of the fuel cell system to maximize efficiency. This present invention recognizes that under certain operating conditions appropriately matched operating pressures enable a substantially more efficient system operation. The method of the present invention and the fuel cell system of the present invention incorporate the recognition that a higher system efficiency can be achieved when the operating pressure produced by the air compressor is matched to the prevailing operating temperature of the fuel cell system.

Abstract: A method and device for operating a fuel cell system. A recirculation loop coupled to a fuel cell cathode ensures that fluids passing through the cathode are recycled, thereby enabling reaction between residual oxygen in the recycled fluid and fuel that has been introduced into the recirculation loop until substantially all of the oxygen is reacted, leaving a substantially oxygen-free, predominantly nitrogen compound in the cathode and related flowpath. Thereafter, this compound can be redirected to purge the remaining residual hydrogen resident in the fuel cell's anode and related flowpath. While the present invention is usable during any period of system operation, it is especially valuable for operational conditions associated with starting up and shutting down a fuel cell system to inhibit the formation of high voltage potentials that could otherwise damage fuel cell catalysts or catalysts supports.

Abstract: One embodiment of the invention includes an MR fluid of improved durability. The MR fluid is particularly useful in devices that subject the fluid to substantial centrifugal forces, such as large fan clutches. A particular embodiment includes a magnetorheological fluid including 10 to 14 wt % of a hydrocarbon-based liquid, 86 to 90 wt % of bimodal magnetizable particles, and 0.05 to 0.5 wt % fumed silica.

Abstract: A method for designing manufacturing systems with speed, flexibility, continuity includes identifying design issues with respect to at least one system concern (e.g., safety, reliability, quality, etc.) at the beginning of the design process. Proposed designs are evaluated according to simultaneous and sequential criteria both during a preliminary stage, before a supplier has been selected, and after a selected supplier offers a more detailed design for the manufacturing equipment. The activities and associated consequences associated with maintaining and operating the equipment being designed are identified and paired together into activity/consequence pairs. An optimized solution is determined for each individual activity/consequence pair and incorporated in the manufacturing equipment's design. After the manufacturing equipment is built, a validation process confirms that the process considerations and process solutions with respect to the particular system concern have been resolved in the final product.

Abstract: One embodiment of the invention includes an MR fluid of improved durability. The MR fluid is particularly useful in devices that subject the fluid to substantial centrifugal forces, such as large fan clutches. A particular embodiment includes a magnetorheological fluid including a liquid, magnetizable particles, and a molybdenum-amine complex.

Abstract: A reactor system including a reactor housing having an inlet portion defined at one end of the housing and having a discharge opening formed in the housing at an opposite end. An air intake charge line is connected to the housing for charging air into the inlet portion. A steam charge line is connected to the housing for charging steam into the inlet portion. A fuel injector is positioned in the housing for injecting fuel into the stream of air and steam flowing through the housing. A fuel charge line is connected to the fuel injector for charging a carbon-based fuel into the injector. A catalyst bed is carried in the housing and positioned downstream of the fuel injector and at least a portion of the catalyst bed includes a catalyst for promoting the reformation of the carbon-based fuel to produce hydrogen. An auto-ignition suppression and carbon-suppression foam is carried in the housing and positioned between the catalyst bed and the fuel injector.

Abstract: A device and method are provided to allow the flowpaths in a fuel cell stack to be reconfigured dependent on reactant gas throughput in order to maintain appropriate pressure drop, sufficient velocities, and reactant concentrations of each cell of a fuel cell stack.

Abstract: A method and apparatus for the operation of a fuel cell system to avoid the freezing of water resident in one or more fuel cells during periods of system inactivity. Each fuel cell includes at least an anode, a cathode and a membrane configured to establish electrolyte communication between reaction products formed at the anode and cathode. During fuel cell system operation, a portion of the water formed remains within the fuel cell; to avoid having the water freeze and inhibit subsequent system operation, a chemical compound introduced into the fuel cells mixes with the water still resident within the fuel cell to lower the temperature upon which the onset of water freezing occurs. The chemical compound can be introduced alone under pressure in the vapour phase, or in combination with the fuel, the incoming oxygen or an inert gas. In addition, system is configured such that the chemical compound can be introduced at numerous different locations.