Abstract: An improved fuel processor thermal management system for use with a fuel cell is disclosed. The process includes supplying an air stream and a fuel stream into a auto thermal reactor (ATR) and forming reformate gas therein. Then, preferentially oxidizing the reformate gas and the air stream in the preferential oxidizer reactor (PrOx). The temperature of the preferential oxidizer reaction is controlled with a water stream by vaporizing the water stream to form a first portion of vaporized water. Then, reacting the air stream with the reformate gas exiting the PrOx is reached in a fuel cell to form an anode exhaust stream which is subsequently combined with the air stream to heat the water stream to form a second portion of vaporized water. The first portion of vaporized water and the second portion of vaporized water form a steam fluid.

Abstract: A cooling fan system for a vehicle with fuel cell propulsion, wherein air is moved by means of a cooling fan for cooling purposes through a heat exchanger and can thereafter be supplied to the environmental air either directly or indirectly after satisfying one or more further cooling tasks, characterized in that an air branching device is provided which supplies at least a part of the air delivered by each fan to a duct and thereby enables the use of the branched-off air for the starting of the fuel cells and/or for the maintenance of the operation of the fuel cells.

Abstract: A cooling fan system for a vehicle with fuel cell propulsion, wherein air is moved by means of a cooling fan for cooling purposes through a heat exchanger and can thereafter be supplied to the environmental air either directly or indirectly after satisfying one or more further cooling tasks, characterized in that an air branching device is provided which supplies at least a part of the air delivered by each fan to a duct and thereby enables the use of the branched-off air for the starting of the fuel cells and/or for the maintenance of the operation of the fuel cells.

Abstract: A process and an apparatus for locating ground faults in motor armatures includes shorting a commutator of a motor armature with a shorting strap and connecting a variable voltage AC power supply and a load in series between the commutator and a core of the motor armature. The magnitude of a voltage applied by the AC power supply to the commutator is increased until current flows through a winding grounded point on the motor armature. Then a probe of a gauss meter is moved along an edge of the core adjacent the commutator to locate a core slot having a highest magnetic field reading measured by the gauss meter. The probe is moved along the core slot with the highest reading until the gauss meter measures a sudden reduction in the magnetic field indicating the grounded point.

Abstract: Various devices and methods for achieving electrochemical energy conversion are presented. In accordance with one embodiment, an energy conversion cell is configured to enable the first and second reactant supplies to communicate selectively with first and second catalytic electrodes of the cell. The selective communication of the first and second reactant supplies with the first and second catalytic electrodes may be attributable to alteration of the reactant supply flow paths or to movement of the first and second catalytic electrodes.

Abstract: The present invention relates to an electrochemical cell having a terminal collector plate element that conducts electrical current from the stack. The terminal plate has an electrically conductive region and an electrically non-conductive region of the surface. The non-conductive region is coated with a corrosion resistant coating that comprises either a passivation layer, a corrosion-resistant polymeric layer, or both. Optionally, the conductive region of the terminal plate may be protected from oxidation, by coating with an oxidation-resistant metal layer. The oxidation-resistant layer may be further coated with a conductive oxidation-resistant polymeric layer. Other preferred aspects of the present invention include methods of treating the terminal plate to resist corrosion and oxidation while still maintaining electrical conductivity.

Abstract: A fuel cell system with flow passages and/or flow chambers which conduct moist gases in operation is characterized in that at least a part of the flow passages and/or flow chambers is provided with a coating which takes up water in distributed form at low temperatures and releases the water again at least in part at higher temperatures. This coating makes it possible to operate the fuel cell system at pronounced temperatures below zero, such as, for example, −40° C., and to ensure an adequate humidification of the operating gases, which protects the membranes from damage and favors a faster starting up of the fuel cell system.

Abstract: A fuel cell stack has at least two segments of fuel cells each having reactant gas passages. Each of the cells in each segment is arranged such that the reactant gas passages of each cell are in parallel with each other cell. Flow of fuel cell fluids, normally in a gaseous state on the anode and cathode side of each cell, is in a gravity assisted downward direction. Gravity assisted flow directs water formed in each cell to lower removal points of the stack segments. Each pair of segments is separated by a separator segment having a separator channel, the separator segment forming an integral unit of the stack. Each separator channel redirects the entire flow of each fluid within the stack from the bottom of an upstream segment to the top of a next or downstream segment, without reacting the fluid, controlling relative humidity between stack segments.

Abstract: A venting methodology and system for rapid shutdown of a fuel cell apparatus of the type used in a vehicle propulsion system. H2 and air flows to the fuel cell stack are slowly bypassed to the combustor upon receipt of a rapid shutdown command. The bypass occurs over a period of time (for example one to five seconds) using conveniently-sized bypass valves. Upon receipt of the rapid shutdown command, the anode inlet of the fuel cell stack is instantaneously vented to a remote vent to remove all H2 from the stack. Airflow to the cathode inlet of the fuel cell stack gradually diminishes over the bypass period, and when the airflow bypass is complete the cathode inlet is also instantaneously vented to a remote vent to eliminate pressure differentials across the stack.

Abstract: Recesses are located along an elongated elastomeric member. Electrical contacts are associated with the elastomeric member in registration with the recesses. The elastomeric member expands or compresses along its length to receive one of the closely spaced plates in each of the plurality of recesses and to thereby register the electrical contacts with a corresponding contact point on the plates. The elastomeric strip is confined under compression between two adjacent members which may be parts of two plates or of a single plate. The adjacent members define a recess, including locking protrusions, adapted to resist removal of the connector from within the retention recess unless the elongated elastomeric strip is compressed. An associated method optionally includes allowing the compressed elastomeric strip to push against adjacent members to generate a force which pushes the contact points against the one of the closely spaced plates.

Abstract: A fuel processor for a fuel cell includes a thermal start device, a mixing region and a temperature control element. The temperature control element is located between the thermal start device and the mixing region. The temperature control element reduces temperature increase in the mixing region during thermal startup. A flame arrestor is connected to the mixing region. A primary reactor is connected to the flame arrestor. The transient temperature control element has a body defining an inlet and an outlet. A plurality of bores are formed in the body.

Abstract: A fuel processor control system for a fuel cell stack includes water and fuel metering devices that control water and fuel provided to the fuel processor. An air flow rate sensor generates an air flow rate signal based on air flowing from a compressor to the fuel processor. A valve is located between the fuel processor and the fuel cell stack. A controller controls the valve and the water and fuel metering devices based on the air flow rate sensor. Other feedback signals such as stack voltage, stack cell voltage variation, pressure differential across the valve, and mass flow rate between the valve and the fuel cell stack can augment or be substituted for the air flow rate feedback signal. The fuel processor can be a partial oxidation reformer a steam reforming reactor, an auto thermal reformer or any combination thereof. The system may also include a water as shift reactor and a preferential oxidation reactor for carbon monoxide reduction.

Abstract: A sensor system for sensing the relative humidity level of gas stream in a fuel cell includes a humidity sensor that senses the relative humidity of a gas stream and generates a relative humidity signal. A pressure sensor senses the pressure of the gas stream and generates a pressure signal. A temperature sensor senses the temperature of the gas stream and generates a temperature signal. A compensator is connected to the humidity sensor, the temperature sensor and/or the pressure sensor. The compensator generates a compensated relative humidity signal based on the relative humidity signal, the temperature signal and/or the pressure signal. Additional inputs to the compensator can include one or more gas composition sensors that determine the concentration of one or more gases.

Abstract: Fuel cell stack having a plurality of liquid-cooled, bipolar plates separating one cell from the next. Coolant inlet and outlet manifolds are defined, in part, by surfaces of the bipolar plates, and respectively supply coolant to, and remove coolant from, the bipolar plates. The surfaces of the bipolar plates that define the coolant manifolds and confront the coolant in the manifolds are coated with a non-conductive coating to reduce shunt current flow through the coolant.

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 rolling regeneration diesel particulate filter and filtering process that utilizes NO produced in the process to generate additional amounts of NO2 than the NO2 produced by the diesel engine. The process includes the step of flowing diesel engine combustion exhaust through a filter system including a first section and a second section. The first section is positioned upstream of the second section with respect to the direction of the flow of the diesel engine exhaust through the filter. The first section includes a foam constructed and arranged to trap carbon-based particulates in the exhaust. A first catalyst is carried by the foam to promote the conversion of NO in the exhaust from the diesel engine to NO2. The first catalyst also promotes the reaction of NO2 with at least a portion of the carbon-based particulates trapped by the foam to form CO and NO.

Abstract: A cooling unit includes a radiator and an axial flow blower that draws air through the radiator along a longitudinal axis and a cross-flow fan that draws air along a lateral axis. The cross-flow fan forces air through the radiator along the longitudinal axis. The axial flow fan draws air through the radiator long the longitudinal axis. A moveable baffle is operable to selectively block air flow from the cross-flow fan.

Abstract: An electrical isolation system is provided for a fuel cell stack as well as a method of operating the fuel cell stack. The stack comprises a plurality of fuel cells connected in series and a coolant circuit for cooling said fuel cells in operation using a liquid coolant having a restricted electrical conductivity. The stack is associated with a chassis having a chassis ground and comprising a plurality of coolant passages for said fuel cells. The coolant circuit comprises a plurality of conductive components such as an outer boundary wall of the fuel cell stack, a radiator and/or a pump at least one of which is connected to said chassis ground. A measuring circuit is provided for measuring the resistance between a selected one of the fuel cells and the chassis ground and a monitoring circuit provides a warning signal, or disengages the connection to the output terminals of the stack or shuts down the stack if the resistance reaches a critical value.

Abstract: Process for improving the efficiency of a fuel cell system having a liquid coolant and a pump circulating the coolant through the fuel cell and a heat exchanger that extracts heat from the coolant. Improved efficiency is achieved by intermittently shutting off the pump when the fuel cell is operating at less than 25% of its “full power” design point.

Abstract: Recesses are located along an elongated elastomeric member. Electrical contacts are associated with the elastomeric member in registration with the recesses. The elastomeric member expands or compresses along its length to receive one of the closely spaced plates in each of the plurality of recesses and to thereby register the electrical contacts with a corresponding contact point on the plates. The elastomeric strip is confined under compression between two adjacent members which may be parts of two plates or of a single plate. The adjacent members define a recess, including locking protrusions, adapted to resist removal of the connector from within the retention recess unless the elongated elastomeric strip is compressed. An associated method optionally includes allowing the compressed elastomeric strip to push against adjacent members to generate a force which pushes the contact points against the one of the closely spaced plates.