Abstract: A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

Abstract: A method and apparatus estimate hydrogen concentration in a reformate stream produced by a fuel processor of a fuel cell. A sensor measures carbon monoxide, carbon dioxide, and water in the reformate stream. A fuel meter controls fuel input to the fuel processor. An air meter controls air input to the fuel processor. A water meter controls water input to the fuel processor. A transport delay estimator recursively estimates transport delay of the fuel processor. A hydrogen estimator associated with the transport delay estimator, the air, water and fuel meters, and the sensor estimates hydrogen concentration in the reformate stream. The hydrogen estimator includes a fuel processor model that is adjusted using the estimated transport delay. The carbon monoxide, the carbon dioxide and the water are measured using a nondispersive infrared (NDIR) sensor.

Abstract: A circuit configuration provides a simple device that can be used to monitor the voltage potential between any two points within the fuel cell coolant system without loading (i.e. decreasing) the voltage being monitored. The monitoring circuit include a lamp electrically coupled to the coolant system and arranged in a light-tight package with a photoresistor. When the ionization voltage for the lamp is reached, a fully isolated signal is provided in the form of an abrupt resistance change in the photoresistor. Visual and audible indicators can be coupled to the monitoring circuit to indicate a coolant contamination condition.

Abstract: A bipolar plate for use with a fuel cell is provided including an electrically conductive foam as a coolant layer between thin metal foil layers. The thin metal foil layers are provided with serpentine flow field patterns on a surface thereof.

Abstract: A fuel processor for rapid start and operational control. The fuel processor includes a reformer, a shift reactor, and a preferential oxidation reactor for deriving hydrogen for use in creating electricity in a plurality of H2—O2 fuel cells. A heating and cooling mechanism is coupled to at least the shift reactor for controlling the critical temperature operation of the shift reactor without the need for a separate cooling loop. This heating and cooling mechanism produces or removes thermal energy as a product of the temperature of the combustion of air and fuel. Anode effluent and cathode effluent or air are used to control the temperature output of the heating mechanism. A vaporizer is provided that heats the PrOx reactor to operating temperature.

Abstract: A fuel processor system capable of circulating fuel processor system gases, such as reformate, anode exhaust, and/or combustor exhaust, through the fuel processor to provide a number of distinct advantages. The fuel processor system having a plurality of fuel cells discharging an H2-containing anode effluent and an O2-containing cathode effluent. A fuel processor is also provided for converting a hydrogen-containing fuel to H2-containing reformate for fueling the plurality of fuel cells. A catalytic combustor is positioned in series downstream from the plurality of fuel cells and a vaporizer reactor is coupled to the catalytic combustor. A bypass passage is finally provided that interconnects an outlet of at least one of the group consisting of the fuel processor, the plurality of fuel cells, the catalytic combustor, and the vaporizer reactor to the inlet of the fuel processor. The bypass passage is operable to circulate a fuel processor system gas to the inlet of the fuel processor.

Abstract: An apparatus and method is disclosed for rapidly heating fuel processor components during startup of a fuel cell powered vehicle. Rapid heating is achieved by placing a water adsorbent downstream of the fuel processor's primary reactor, which converts a hydrocarbon-based fuel to a hydrogen-rich fuel. In addition to hydrogen, the reformed fuel (reformate) includes carbon dioxide, carbon monoxide and water. The water adsorbent, which has a high heat of adsorption, produces heat as it adsorbs water in the reformate. Heat generated by water adsorption enhances the rate at which fuel processor components, such as a water-gas-shift reactor, reach their operating temperatures. In addition, water adsorption reduces water condensation on the water-gas-shift reactor catalyst. Once the fuel processor components attain their operating temperatures, water desorbs from the adsorbent and is available for converting carbon monoxide to carbon dioxide and hydrogen in the water-gas-shift reactor.

Abstract: Apparatus for cooling a fuel cell stack. The cooling system uses vaporization cooling of the fuel stack and supersonic vapor compression of the vaporized coolant to significantly increase the temperature and pressure of the liquid coolant flowing through a heat exchanger. By increasing the heat rejection temperature of the coolant delivered to the heat exchanger, the heat transfer area of the heat exchanger can be reduced and the mass flow rate of coolant can also be reduced. The increased fluid pressure is used to circulate the coolant through the cooling system, thereby eliminating the circulation pump associated with conventional systems.

Abstract: A fuel cell system that can be used to power a vehicle is disclosed. The system includes a fuel cell stack, which uses hydrogen and an oxidizer to generate electricity, and a re-circulation loop that returns unreacted hydrogen to the fuel cell stack. The system includes a hermetically sealed assembly having a blower portion that pressurizes hydrogen in the re-circulation loop and a motor portion that drives the blower. The system also includes a source of make-up hydrogen for replenishing hydrogen in the re-circulation loop. The source introduces make-up hydrogen in the motor portion of the assembly at a pressure greater than the pressure in the blower portion of the assembly. Consequently, make-up hydrogen flows from the motor portion of the assembly into the blower portion assembly where it mixes with components in the re-circulation loop. A method of replenishing hydrogen in the fuel cell stack is also disclosed.

Abstract: A composite separator plate for use in a fuel cell stack and method of manufacture is provided. The composite separator plate includes a plurality of elongated support members oriented generally parallel to each other and a polymeric body portion formed around the support members. The body portion includes a first surface with a plurality of flow channels and a second surface opposite the first surface. A plurality of electrically conductive fibers are disposed within the polymeric body portion, each fiber extending continuously from the first surface of the polymeric body portion to the second surface of the polymeric body portion in a through plane configuration.

Abstract: A double walled fuel line connects diesel fuel injectors in a common rail system. An inner line carries high pressure fuel from a fuel pump to the fuel injectors. Low pressure return fuel flows back through an outer fuel line which acts as a return line. The double walled line reduces the number of separate pipe connections needed in the system and provides protection against loss of high pressure fuel from the system as well as a simplified method for detecting fuel leaks. Monitoring fuel pressure in the low pressure line allows a fuel pressure sensor to detect leaks in the system by comparing fuel pressure in the low pressure line against typical line pressure. Higher than normal pressure in the low pressure line indicates a leak in the high pressure line. Lower than normal pressure indicates a leak in the low pressure return line.

Abstract: A sensor plate for measuring current and/or temperature distribution of an operating fuel cell. The sensor plate has a circuit board interposed between an anode flow field plate and a cathode flow field plate of the fuel cell. A flow field plate is segmented into a plurality of electrically isolated regions without disrupting the flow field of the plate. The circuit board has an array of resistors and/or thermistors mounted to it wherein each resistor and/or thermistor is associated with one of the electrically isolated regions of the segmented plate. The current distribution of the electrically isolated regions of the fuel cell is calculated by using the voltage drop across the resistors and the known resistance values of the resistors mounted to the circuit board.

Abstract: A low humidification and durable fuel cell membrane is provided with water adsorbing material embedded therein in order to adsorb water under wet conditions and provide a reservoir of water to keep the membrane irrigated under dry conditions. A hydrogen oxidation catalyst is provided on the water adsorbing material which will catalyze the reaction of hydrogen and oxygen that are crossing through the membrane and will serve to irrigate the membrane and keep the water adsorbing material full of water. Accordingly, the humidification requirements to a fuel cell stack in an operating system are reduced.

Abstract: A preferential oxidation reactor is provided including a plurality of reactor sections. The reactor sections are individually optimized for operating at a preferred reaction temperature. In one embodiment, each reactor subsection includes a respective coolant flow for manipulating the operating temperature of the respective subsection. In another embodiment, a first section includes a lower temperature catalyst substrate, a second reactor section includes a higher temperature (i.e. normal) catalyst substrate and a third reactor section includes a lower temperature catalyst substrate. Yet another embodiment includes modifying the catalyst substrates of the respective subsections through the inclusion of promoters. Still another embodiment includes varying a density of the catalyst substrate across the reactor sections. Each of the embodiments enable quick light-off of the reactor, while limiting a reverse water-gas shift reaction.

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, 0.05 to 0.5 wt % fumed silica, and an additive package including a paraffin oil, a phenol and a sulfide.

Abstract: A diesel engine emission control system which optimizes fuel injection timing over a range of air temperatures, air pressures, and engine air flow rates. The emission control system includes a control module interfacing with a fuel injection timing module which in turn interfaces with an engine fuel injection system having fuel injectors. The control module receives data from an air temperature sensor, an air pressure sensor, and an engine boost pressure sensor. The control module determines air density and the air flow rate through the engine to determine optimal fuel injection timing. The injection timing information is relayed to the injection timing module which alters the timing of the fuel injectors to operate the engine at a maximum efficiency possible within applicable emission regulation limits.

Abstract: A fuel cell system having a dynamically controlled pressure regulator for varying the backpressure on the system under varying ambient temperatures and pressures.

Abstract: A PEM fuel cell having a current collector comprising a polymer composite and a diffusion media engaging said polymer composite. The polymer composite has a hyperconductive surface layer engaging the diffusion media to reduce the contact resistance therebetween. The hyperconductive surface layer is formed by depositing or smearing an electrically-conductive material on the surface of the polymer composite.

Abstract: The present invention relates to methods of torque transfer, torque transfer units, and vehicles incorporating the same. According to the method, a delta signal indicative of a rotational condition of the first driveline is generated and a torque transfer unit is controlled as a function of a torque transfer control algorithm. The control algorithm commands a transfer torque representing an amount of torque to transfer from the source of power to one of the first and second drivelines. The torque transfer control algorithm is a function of the delta signal and is substantially independent of any rotational condition of the second driveline over a primary operational range of the algorithm. Reference values may comprise a desired vehicle acceleration value, an actual vehicle acceleration value, a vehicle ground speed value, temporally displaced first driveline acceleration values, temporally displaced first driveline speed values, and combinations thereof.

Abstract: A burner arrangement for the combustion of a fuel gas/oxygen mixture, characterized by a body permeable for the mixture whose surface regions defining the free cross section of flow are covered with an oxidation catalyst, by a feeder device arranged on an intake side of the body permeable for the mixture which distributes the mixture over at least essentially the entire active intake area of the intake side and by a layer coordinated with the feeder device and separating the catalytic combustion zone of the permeable body from the mixture inflow, but permeable for it, which serves as a flashback safety.