Abstract: A fuel cell system which provides stable cell outputs at startup.

Abstract: A fuel cell stack module includes a plurality of fuel cell stacks, an anode tail gas oxidizer (ATO) which is located in a heat transfer relationship with the plurality of fuel cell stacks, a base supporting the plurality of fuel cell stacks and the ATO, and at least one heat exchanger located in the base. An ATO exhaust stream and an anode exhaust stream from the fuel cell stacks heat the stack fuel and air inlet streams in a multi-stream heat exchanger.

Abstract: A fuel cell power plant (9) includes a stack (10) of fuel cells, each including anodes (11), cathodes (12), coolant channels (13) and either (a) a coolant accumulator (60) and a pump (61) or (b) a condenser and cooler fan. During shutdown, electricity generated in the fuel cell in response to boil-off hydrogen gas (18) powers a controller (20), an air pump (52), which may increase air utilization to prevent cell voltages over 0.85 during shutdown, and either (a) the coolant pump or (b) the cooler fan. Operation of the fuel cell keeps it warm; circulating the warm coolant prevents freezing of the coolant and plumbing. The effluent of the cathodes and/or anodes is provided to a catalytic burner (48) to consume all hydrogen before exhaust to ambient. An HVAC in a compartment of a vehicle may operate using electricity from the fuel cell during boil-off.

Abstract: A cooling system for the shutdown process in a fuel cell powered vehicle system for eliminating the detrimental effects of voltage persistence in the fuel cell including a volume of fluid coolant at ambient temperature, a pump, a fluid circuit interconnecting the pump and the coolant reservoir with a section of a cooling system that circulates through the vehicle fuel cell stack, and a controllable valve system whereby, at the occurrence of vehicle shutdown, the ambient temperature fluid in the reservoir is directed to a section of a cooling system that circulates through the vehicle fuel cell stack.

Abstract: Systems and methods for initiating use of, or starting up, fuel cell stacks in subfreezing temperatures. The fuel cell stacks include a thermal management system that is adapted to deliver a liquid heat exchange fluid into thermal communication with a fuel cell stack, such as to heat the stack during startup of the stack when the stack is at a subfreezing temperature or operated in a subfreezing environment. In some embodiments, the thermal management system includes a heat exchange circuit that is configured to provide delivery of the liquid heat exchange fluid to the fuel cell stack even when the conduits are at a subfreezing temperature. In some embodiments, the fuel cell system is configured to deliver liquid heat exchange fluid from the fuel cell stack and heat exchange circuit when the thermal management system is not being utilized.

Abstract: A fuel cell and an electronic apparatus with same mounted thereon are provided. The fuel cell includes a power generation unit provided with a conduit for an oxidant gas containing at least oxygen, a heat radiation unit connected to the power generation unit so as to radiate heat from the power generation unit, a gas flow means for causing the oxidant gas to flow in the conduit, and a cooling means driven independently from the gas flow means so as to cool the heat radiation unit. By independently controlling the driving of the gas flow means and the cooling means, the fuel cell can be driven in such a manner that the temperature of the power generation unit and the amount of water remaining in the power generation unit are regulated into preferable conditions. Furthermore, it is possible to provide a fuel cell and an electronic apparatus with the same mounted thereon in which power generation can be performed stably and various apparatuses are contained therein in a compact form.

Abstract: A fuel cell system includes a first fuel cell stack, a second fuel cell stack arranged in a cascade configuration with the first fuel cell stack, and at least one hydrocarbon fuel reformer which is thermally integrated with at least a portion of the first stack. The system is configured such that in operation, at least partial reformation of hydrocarbon fuel occurs prior to entry into the first stack or in the first stack, and the second stack uses fuel exhaust from the first stack as fuel. A method of operating the fuel cell system includes reforming a hydrocarbon fuel to form a reformed fuel while cooling at least a portion of a first fuel cell stack, generating electricity in the first fuel cell stack using the reformed fuel, providing a fuel exhaust stream from the first fuel cell stack into a second fuel cell stack, and generating electricity in the second fuel cell stack using the fuel exhaust stream from the first fuel stack as a fuel.

Abstract: The invention concerns an energy production unit, of electric energy in particular, comprising a fuel cell (1) and a heat source (2) thermally coupled to the fuel cell (1) at least to allow the rise in temperature of this fuel cell (1). According to the invention, it is provided that the heat source (2) comprises a radiating burner (20), that the fuel cell (1) is confined within a thermal insulation enclosure itself heated by the combustion gases (F) derived from the burner (20), and that this unit also comprises temperature regulation means (4) capable of controlling, from around 200° C. to at least 800° C., the temperature of the combustion gases (F) heating the enclosure 3.

Abstract: A fuel cell system includes a fuel cell stack, a combustor, a heat exchanger, and heat utilization equipment. Further, the fuel cell system includes a bypass channel and a control device. In the bypass channel, at least some of heat medium produced in the combustor is supplied to the heat utilization equipment, bypassing the heat exchanger. The control unit adjusts the supply of the heat energy supplied to the fuel cell stack through an oxygen-containing gas heated by the heat exchanger, and adjusts the heat energy of the heat medium which passes through the bypass channel, and which is supplied to the heat utilization equipment.

Abstract: The power supply apparatus includes a power supply unit, a piezoelectric element for transferring heat of the power supply unit to a floor panel, and an element power supply control circuit for controlling application of a voltage to the piezoelectric element. The piezoelectric element is placed between the power supply unit and the floor panel and is switched between a contact state in which the piezoelectric element is in contact with the power supply unit and the floor panel and a non-contact state in which the piezoelectric element is not in contact with the power supply unit and/or the floor panel in accordance with the application of a voltage.

Abstract: A fuel cell power plant assembly includes an accumulator having a housing. In one example, at least one demineralizer portion is positioned to interact with fluid within the accumulator housing. This allows for warm fluid within the accumulator housing to provide heat to the demineralizer portion. In one example, the demineralizer portion is within the housing. Another example includes a separator supported within the housing of the accumulator. A disclosed example includes a conical shaped baffle as the separator. The separator separates liquid from gas and facilitates distributing fluid flow within the accumulator housing to provide increased heat exchange with the demineralizer portion within the housing.

Abstract: A fuel cell hybrid power generation system for use in a gas distribution system in which a higher pressure gas is transported/distributed and reduced to a lower pressure gas for a gas distribution or transmission line and a pre-heater is used to heat the higher pressure gas before it is reduced in pressure. The power generation system includes: (i) a fuel cell power plant that generates electricity while producing heat that is used to preheat high pressure gas; (ii) an energy recovery generator that uses the pre-heated higher pressure gas to generate electricity while reducing the gas pressure to a lower gas pressure; and (iii) an electrical assembly combining the electrical outputs of the energy recovery generator and the fuel cell power plant. The fuel cell power plant makes the waste heat available to the gas pre-heater without using a combustion unit thereby increasing the system's electrical efficiency.

Abstract: Embodiments are disclosed that relate to increasing radiative heat transfer in a steam reformer from an exterior shell which includes a diffusion burner to an interior reactor via angled fins coupled to the exterior shell. For example, one disclosed embodiment provides a steam reformer, comprising an exterior shell which includes a diffusion burner and angled fins, the angled fins extending away from an inner surface of the exterior shell and downward toward the diffusion burner. The steam reformer further comprises an interior reactor positioned at least partly within the exterior shell.

Abstract: A flow control assembly for use in a fuel cell system, comprising a sensor for sensing hydrogen concentration in one of anode exhaust leaving an anode side of the fuel cell system and a gas derived from the anode exhaust, and a fuel flow control assembly for controlling the flow of fuel to the anode side of the fuel cell system based on the hydrogen concentration sensed by the sensor.

Abstract: A solid oxide fuel cell includes a core with an anode inlet, an anode outlet, a cathode inlet and a cathode outlet. A first heater is connected to the anode inlet of the core. A second heater is connected to the cathode inlet of the core. A reformer is connected to the first heater. A heat exchanger is connected to the second heater. A burner is connected to the reformer and the anode and cathode outlets of the core. A humidifier is connected to the reformer. A first gas supply is connected to the humidifier. A second gas supply is connected to the reformer. A third gas supply is connected to the burner. A fourth gas supply is connected to the heat exchanger.

Abstract: An integrated charge air heat exchanger for use in a vehicle fuel cell system is provided. The integrated charge air heat exchanger includes a plurality of coolant conduits adapted for a coolant fluid to flow therethrough. The integrated charge air heat exchanger further includes a plurality of heating elements and a plurality of fin elements. One heating element is disposed on a first surface of each of the coolant conduits, and one of the fin elements is disposed on a second surface of each of the coolant conduits. A method for heating the coolant fluid in a first operational mode and cooling a charge air stream in a second operational mode is also provided.

Abstract: A fuel cell system that employs a heat exchanger and a charge air cooler for reducing the temperature of the cathode inlet air to a fuel cell stack during certain system operating conditions so that the cathode inlet air is able to absorb more moisture in a water vapor transfer unit. The system can include a valve that selectively by-passes the heat exchanger if the cathode inlet air does not need to be cooled to meet the inlet humidity requirements. Alternately, the charge air cooler can be cooled by an ambient airflow.

Abstract: One embodiment of the invention includes a cooling tank reservoir with a pressure release valve and a cooling fluid conduit wrapped around the pressure release valve.

Abstract: In at least one embodiment, an apparatus comprising a hydrogen storage system and a heat storage system is provided. The hydrogen storage system is configured to store hydrogen and to deliver a first heated fluid stream to an electrical generation system that generates a second heated fluid stream and electrical energy in response to the first heated fluid stream. The heat storage system includes a phase change material. The heat storage system is in fluid communication with the electrical generation system to deliver heat from the second heated fluid stream to a fuel cell stack.

Abstract: An electronic apparatus having a fuel cell which sufficiently supplies air to the fuel cell without a separate air pump or fan. In the electronic apparatus, a cooling fan cools heat-generating parts of an external device having the fuel cell mounted thereon. A guide bracket guides wind of the cooling fan, upon having cooled the heat-generating parts, toward a fuel cell.

Abstract: Fuel cell systems and methods are described. A method for generating electrical energy in a fuel cell receives hydrogen from a fuel processor configured to process a fuel source to produce the hydrogen, includes transporting a heating medium from the fuel processor to the fuel cell when electrical energy output by the fuel cell includes less than an electrical threshold or when temperature of a component in the fuel cell is less than a temperature threshold, heating a portion of the fuel cell, transporting hydrogen from the fuel processor to the fuel cell, detecting temperature of the component or electrical output of the fuel cell, and generating electrical energy in the fuel cell when the temperature of the component is about equal to or greater than the threshold temperature or when electrical energy output by the fuel cell is about equal to or greater than an electrical threshold.

Abstract: A power generation system has a fuel cell stack and at least one condensation point in the system at which water present after shutdown of the power generation system can condense or collect. Drying after shutdown is improved by maintaining a temperature gradient between the condensation point and at least one other component in the power generation system after shutdown. In one embodiment, the temperature gradient is maintained by housing the fuel cell stack in a thermally insulated container and arranging the condensation point outside of the insulating container. In another embodiment, drying after shutdown is accomplished with an adsorption unit having a water-adsorbing material arranged in a desired location within the power generation system.

Abstract: Systems and methods for initiating use of, or starting up, fuel cell stacks in subfreezing temperatures. The fuel cell stacks include a thermal management system that is adapted to deliver a liquid heat exchange fluid into thermal communication with a fuel cell stack, such as to heat the stack during startup of the stack when the stack is at a subfreezing temperature or operated in a subfreezing environment. In some embodiments, the thermal management system includes a heat exchange circuit that is configured to provide delivery of the liquid heat exchange fluid to the fuel cell stack even when the conduits are at a subfreezing temperature. In some embodiments, the fuel cell system is configured to deliver liquid heat exchange fluid from the fuel cell stack and heat exchange circuit when the thermal management system is not being utilized.

Abstract: A heat transfer controlling mechanism and a fuel cell system, which allow working fluid to flow in a predetermined direction in a loop-shaped flow path without a back flow, having a simple structure independent of the orientation during use, low power consumption, and efficient heat transfer and size reduction. The mechanism includes a vaporizing portion, a condensing portion, and a loop-shaped flow path connecting the vaporizing and the condensing portions so as to seal working fluid. The mechanism transports heat by vaporizing the fluid in the vaporizing portion and condensing the fluid in the condensing portion to control heat transfer. The mechanism further includes a gas passage suppressing portion on one side in the flow path, for allowing liquid, but not gas, to pass therethrough and a liquid passage suppressing portion on the other side in the flow path, for allowing gas, but not liquid, to pass therethrough.

Abstract: An improved CHP system combining a VCCHP system with an SOFC system for application as a combined CHP system wherein the compressor motor of a heat pump is powered by a portion of the electricity generated by the SOFC, and wherein the thermal output of the heat pump is increased by abstraction of heat from the SOFC exhaust. This integration allows for complementary operation of each type of system, with the benefits of improved overall fuel efficiency for the improved CHP system. The heat pump is further provided with a plurality of flow-reversing valves and an additional heat exchanger, allowing the heat pump system to be reversed and thus to operate as an air conditioning system.

Abstract: A heat exchanger that can mechanically automatically control a level of cooling water according to heat generation of the fuel cell. The heat exchanger includes a housing having a cooling water inlet and an outlet connected to a fuel cell stack, a moving plate which moves reciprocally in the housing and discharges cooling water filled in the housing to the stack when it moves in a one direction and when it receives a steam pressure from the stack it moves in an opposite direction, and an elastic member that applies a force to the moving plate in the one direction. The heat exchanger can automatically maintain the level of cooling water despite a difference in heat generated between a full and a partial load operation of the fuel cell obviating complicated electronics such as a thermo-sensor, a valve, or a controller. Also, under a partial load, the exposure of flow channels to superheated steam is avoided, thereby extending the lifetime of the fuel cell.

Abstract: The invention relates to a radiant gas burner device comprising a first cylindrical chamber (1) and a first injector (2) for feeding the first chamber with a combustible gas mixture, the first chamber (1) comprising an external peripheral heating surface (10). The device of the invention further comprises a second cylindrical and hollow second chamber, and a second injector (4) for feeding the second chamber with a combustible gas mixture, the second chamber being positioned inside the first chamber (1), separated from the first chamber by a sealed wall, and having an internal heating surface (30), and the first and second injectors (2, 4) being designed for separately feeding the first and second chambers, independently of each other.

Abstract: The fuel cell system is provided which detects a freeze among specific components and portions thereof by evaluating various conditions upon starting operation of the fuel cell system. If a freeze is detected through those evaluations, the start of the system is prohibited in order to prevent some deterioration in the fuel cell system.

Abstract: The present invention relates to a process for the deionization of a cooling medium in a fuel cell (11) circulating in a cooling circuit (20), in which the cooling medium is subjected to at least intermittent, but preferably continuous, electrochemical deionization. To this end, at least one electrode deionization cell (23) , through which a diluate stream (27) serving as cooling medium and a concentrate stream (28) flow, is arranged in the cooling circuit. The concentrate stream (28) may be part of a secondary cooling circuit.

Abstract: In a fuel cell system including a fuel cell supplied with reaction gases for generating an electric power, and a combustion heater supplied with the reaction gases for heating the fuel cell during warming-up, an electric discharging circuit is provided to discharge an electric current from the fuel cell supplied with the reaction gases to decrease a voltage difference applied to the membrane sandwiched between the anode and cathode during the warming-up. The combustion heater is connected in series or in parallel with the fuel cell system.

Abstract: A system includes a radiator side flow path (9) for supplying a coolant which has cooled a fuel cell stack (1) to a radiator (5), a bypass flow path (7) for allowing the coolant which has cooled the fuel cell stack (1) to bypass the radiator (5), a thermostat valve (8) for increasing a flow rate of the coolant flowing through the radiator side flow path (9) in a case where the temperature of the coolant is high as compared to a case where the temperature of the coolant is low, and an electric heater (10) for warming up the coolant. The electric heater (10) is controlled based on an outside atmospheric pressure and on the temperature of the coolant such that the temperature of the coolant flowing into the fuel cell stack (1) is raised in a case where the outside atmospheric pressure is high as compared to a case where the outside atmospheric pressure is low.

Abstract: A catalytic combustion unit for a fuel cell system is provided. The catalytic combustion unit includes a reactor having a porous medium with a catalyst deposited thereon. The reactor is disposed adjacent a heat exchanger and adapted to receive an air stream and a hydrogen stream. The reactor is further adapted to promote an exothermic reaction and modulate a temperature of a fuel cell stack. A fuel cell system and method employing the catalytic combustion unit are also provided.

Abstract: Improved water distribution can be obtained within the cells of a fuel cell series stack by maintaining a suitable temperature difference between the cathode and anode sides of each cell in the stack during shutdown. This can be accomplished by thermally insulating the “hot” end and sides of the stack and by providing a thermal mass adjacent to the “hot” end.

Abstract: A fuel cell system of the present invention comprises a fuel cell (13), a load value detecting means (16) configured to detect a load value of a load of electric power or heat which is generated by equipment (14) supplied with the electric power or the heat from the fuel cell system, a load value storage means (17) configured to store a history of the load value which is detected by the load value detecting means (16), a load value predicting means (18) configured to predict a load value which is going to be generated, based on the history of the load value, and to store the predicted load value as load value data, and scheduled start-up time of a fuel cell (13) is decided based on the load value data.

Abstract: A fuel cell system comprises: a fuel container for storing fuel liquefied with pressure; a reformer for generating hydrogen from the fuel through a catalyst reaction based on heat energy; an electric generator for generating electricity by transforming energy of an electrochemical reaction between hydrogen and oxygen into electric energy; a condenser for condensing water produced in the electric generator; and a heat exchanger passing through the condenser for cooling the condenser by latent heat of the fuel. With this configuration, cooling water cooled by latent heat of a fuel container is employed to cool the condenser without using a separate cooler. Furthermore, air is mixed with butane fuel without using a separate power unit, so that it is possible to achieve a more compact and highly efficient fuel cell.

Abstract: A cartridge-type ion removal filter 15 to remove ions from the cooling liquid in the cooling liquid circulation passage 20 is disposed in the middle of a cooling liquid circulation passage 20 to circulate the cooling liquid between a fuel cell stack 11 and a radiator 12. The ion removal filter 15 is disposed in the cooling liquid circulation passage so that an opening 26b of a vessel main body 26 is in a higher position than the highest level “H” of the cooling liquid in the reservoir tank 14.

Abstract: The invention relates to fuel cell systems with improved thermal efficiency. The systems include a fuel cell that generates electrical energy using hydrogen and a fuel processor that produces hydrogen from a fuel. Some heat efficient systems described herein include a thermal catalyst that generates heat when the catalyst interacts with a heating medium. The heat is used to heat the fuel cell. The thermal catalyst may be disposed in proximity to the fuel cell, or remote from the fuel cell and a heat transfer pipe conducts heat from the catalyst to the fuel cell. Another thermally efficient embodiment uses a recuperator to transfer heat generated in the fuel cell system to incoming fuel. A fuel cell package may also include a multi-layer insulation arrangement to decrease heat loss from the fuel cell and fuel processor, which both typically operate at elevated temperatures.

Abstract: A water generation system for the generation of water on board an aircraft comprises a fuel cell device having an exhaust for an exhaust gas, a condenser and an outflow valve for discharging cabin air, which is drawn off through the condenser due to the pressure difference between the cabin pressure and ambient pressure without extensive cooling circuits or pumps, for example. The condenser may be coupled to the exhaust such that the exhaust gas is cooled by cabin air, and the outflow valve is connected to the condenser and to the environment of the aircraft, such that, when the aircraft is at cruising altitude, the cabin air is drawn through the condenser and is discharged into the environment.

Abstract: A fuel cell assembly in which at least one heat exchanger for conditioning either the anode or cathode reactant gas is integrated with the fuel cell stack and located at the end of the fuel cell stack, to isolate the fuel cell stack from contact with the end plates of the stack. The heat exchanger may preferably be comprised of a stack of plates which may preferably be the same as the plates as the fuel cell stack, with outer and inner end plates to direct the flow of reactant gases, waste gases and coolant to and from the fuel cell stack. The assembly is preferably configured to include reactant conditioning heat exchangers at both ends of the fuel cell stack.

Abstract: A post-control electric power amount curve generating portion generates plural pieces of running control information indicating a changeable running method for each device and plural post-control electric power amount curves indicating an amount of main electric power. A post-control hot water storage amount curve generating portion generates post-control hot water storage amount curves each indicating an accumulated amount of hot water generated in a case where the fuel cell generates electric power based on the plural post-control electric power amount curves. A hot water storage completion determining portion determines whether the accumulated amounts exceed a specific heat capacity. A reduction amount calculating portion calculates plural energy cost reduction amounts produced before and after the change using the post-control hot water storage amount curves determined as not exceeding the specific heat capacity.

Abstract: A fuel cell system includes a fuel cell stack that receives a cathode feed gas and has an exhaust stream and a heat transfer stream flowing therefrom. A charge-air heat exchanger enables heat transfer between the heat transfer stream and the cathode feed gas. The charge-air heat exchanger also enables heat transfer between the heat transfer stream and the cathode feed gas to compensate for the adiabatic cooling effect. Furthermore, the charge-air heat exchanger vaporizes the liquid water to provide water vapor. The water vapor humidifies the cathode feed gas.

Abstract: A fuel cell is provided for improving the starting performance at low temperatures. The fuel cell includes a cell structure in which an anode and a cathode are provided on either side of a solid polymer electrolyte membrane. The fuel cell may include a first cooling liquid passage and a second cooling liquid passage independent of the first cooling liquid passage. Cooling liquid is heated by an external heating device and supplied to the second cooling liquid passage.

Abstract: A multi-unit fuel cell system that includes a common-use reforming unit configured to supply hydrogen to multiple fuel cell units that are installed in multiple units, such as apartments within an apartment building. In one example embodiment, a fuel cell system including a common-use reforming unit and multiple fuel cell units is disclosed. The common-use reforming unit is configured to supply hydrogen to the plurality of fuel cell units. Each fuel cell unit includes a stack unit, an air supplying unit, an integral heat exchange unit, a hot-water supplying unit, an auxiliary heat supplying unit, and an electric output unit.

Abstract: This fuel cell system is equipped with a fuel cell having a reaction gas flow passage, generating power by the reaction gas being supplied to the reaction gas flow passage, having a refrigerant flow passage, and cooled by the refrigerant being supplied to the refrigerant flow passage; a reaction gas supply device for supplying the reaction gas to the reaction gas flow passage; a refrigerant supply device for supplying the refrigerant to the refrigerant flow passage; a refrigerant supply restriction device for restricting a refrigerant supply amount to the refrigerant flow passage; and a controller for controlling the refrigerant supply restriction device, wherein the reaction gas refrigerant supply devices have a drive device in common and are integrally driven, and wherein when warming up the fuel cell, the controller controls the refrigerant supply restriction device and reduces the refrigerant supply amount to the refrigerant flow passage.

Abstract: A catalytic combustion unit for a fuel cell system is provided. The catalytic combustion unit includes a reactor having a porous medium with a catalyst deposited thereon. The reactor is disposed adjacent a heat exchanger and adapted to receive an air stream and a hydrogen stream. The reactor is further adapted to promote an exothermic reaction and modulate a temperature of a fuel cell stack. A fuel cell system and method employing the catalytic combustion unit are also provided.

Abstract: A control apparatus for a fuel cell stack includes a fuel cell stack having a stacked body formed by stacking fuel cell units together and a pair of end plates sandwiching the stacked body therebetween; electrical heaters disposed near the ends of the stacked body or the end plates, respectively; a water purging device for purging water which is generated during a power generation operation in the fuel cell stack, and which is held in the fuel cell units; and a control unit which controls the power generation operation in the fuel cell stack, and which is operatively connected to the electrical heaters and the water purging device. The control unit is adapted to operate the electrical heaters and the water purging device when the power generation operation is stopped.

Abstract: Disclosed herein is a heat exchange system for battery packs, which controls the temperature of a medium- or large-sized battery pack including a plurality of unit cells such that the battery pack can be operated under the optimum operating conditions. The heat exchange system includes an air inlet port and an air outlet port formed at one side of a housing surrounding the outer surface of the battery pack so as to form a predetermined flow channel, through which air flows, a driving fan mounted in the flow channel for driving the air to flow through the flow channel, and a Peltier element mounted at the air inlet port for controlling the temperature of air introduced into the air inlet port. In the heat exchange system according to the present invention, the thermoelectric element is mounted inside the air inlet port, through which air for cooling the battery pack is introduced into the heat exchange system.

Abstract: A system and method for determining whether a fuel cell stack is overheating. The system measures the temperature of end cells in the stack using end cell temperature sensors, and calculates an average end cell temperature based on the end cell temperature measurements. The system also measures the temperature of a cooling fluid being output from the fuel cell stack. The system determines if any of the measured end cell temperatures are outlying by comparing each end cell temperature measurement to the average. The system determines that the cooling fluid outlet temperature sensor has possibly failed if the cooling fluid outlet temperature is greater than the average end cell temperature and the cooling fluid outlet temperature minus the average end cell temperature is greater than a predetermined temperature value.

Abstract: A fuel cell system (1) is provided and includes a fuel cell stack (3) and a heat transfer device (5) adapted to transfer heat from a cathode exhaust stream of the fuel cell stack (3) to water to be provided to a fuel inlet stream.

Abstract: A catalytic combustion unit for a fuel cell system is provided. The catalytic combustion unit includes a reactor having a porous medium with a catalyst deposited thereon. The reactor is disposed adjacent a heat exchanger and adapted to receive an air stream and a hydrogen stream. The reactor is further adapted to promote an exothermic reaction and modulate a temperature of a fuel cell stack. A fuel cell system and method employing the catalytic combustion unit are also provided.