Abstract: Devices and methods to control a cathode backpressure valve and a bypass valve in a vehicle fuel cell system. A feedforward-based control strategy is used to control the cathode backpressure valve. The control over the bypass valve is integrated into the control over the cathode backpressure valve. Such a control strategy acts in a predictive manner to improve valve response to transitory cathode pressure and bypass flow split setpoints in the system.

Abstract: Assemblies and methods for measuring in-situ membrane fluid crossover are provided. One embodiment of an in-situ fuel cell membrane crossover measurement assembly as disclosed herein comprises an anode fluid supply configured to supply anode fluid to an anode side of a proton exchange membrane; a cathode fluid supply configured to supply cathode fluid to a cathode side of the proton exchange membrane; a collection chamber configured to receive an exhaust from one of the anode side and the cathode side of the proton exchange membrane; and means for detecting a crossover fluid in the exhaust. The crossover fluid is from the cathode fluid if the exhaust is collected from the anode side and the crossover fluid is from the anode fluid if the exhaust is collected from the cathode side.

Abstract: A fuel cell system includes a pressure regulating valve configured to control a pressure of an anode gas to be supplied to a fuel cell, a pulsation operation control means configured to control such that the anode gas pressure becomes higher as a load becomes larger, and the anode gas pressure is pulsated at the same load, and an anode gas pressure limiting means configured to limit the anode gas pressure by a pressure higher than the anode gas pressure according to the load when the load lowers.

Abstract: A fuel cell system is configured to: calculate a target stack supply flow rate; calculate a compressor supply flow rate based on a stack supply flow rate and the target stack supply flow rate; set a larger one of the compressor supply flow rate and a lower limit flow rate, determined depending on an operation state of the fuel cell system, as a target compressor supply flow rate; control a bypass valve based on the stack supply flow rate and the target stack supply flow rate; fix the bypass valve when the stack supply flow rate is in a predetermined bypass valve fixing range, and the stack supply flow rate becomes less than the target stack supply flow rate; and release the fixation of the bypass valve when the target compressor supply flow rate becomes more than the lower limit flow rate after the bypass valve is fixed.

Abstract: An electromagnetic main stop valve which is opened by an electromagnetic force of a solenoid with energization of a valve body in a valve-closing direction by energizing unit is provided in a hydrogen tank. A current sensor and the accelerator opening-degree sensor for detecting a use gas flow rate in a fuel cell stack are provided. A pressure sensor for detecting a pressure in the hydrogen tank is provided. The control device sequentially sets the electromagnetic force of the solenoid so that a valve-opening amount is such an amount as to supply a use gas flow rate to the fuel cell stack based on detection values of the current sensor or the accelerator opening-degree sensor, and the pressure sensor. When the flow rate of hydrogen gas flowing into a gas supply path increases due to a hydrogen gas leak, the main stop valve is automatically closed.

Abstract: A fuel cell system includes a fuel cell formed by stacking a plurality of power generation cells, and an oxygen-containing gas supply apparatus for supplying an oxygen-containing gas to the fuel cell. The oxygen-containing gas supply apparatus includes an oxygen-containing gas supply channel connected to an oxygen-containing gas inlet of the fuel cell for allowing the oxygen-containing gas to flow from an air pump into the oxygen-containing gas inlet, a branch supply channel branched from the oxygen-containing gas supply channel and which is opened to the inside of a fuel cell chamber, an oxygen-containing gas discharge channel for discharging an oxygen-containing off gas from the fuel cell, and an oxygen-containing off gas circulation channel one end of which is connected to the oxygen-containing gas discharge channel, and another end of which is connected to the oxygen-containing gas supply channel at a position upstream from the air pump.

Abstract: A fuel cell system includes a fuel cell, a controller, a resistance sensor, and a regulator. The fuel cell has a cathode plate, an anode plate, and an ion-exchange membrane interposed between the cathode plate and the anode plate. The controller is for controlling a gas flow rate to the anode plate. The resistance sensor is coupled to the fuel cell for measuring a resistance of the fuel cell. The regulator is coupled to the controller and coupled to the anode plate for regulating the gas flow to the anode plate. The controller receives a signal from the resistance sensor and is configured to control the regulator to adjust the gas flow to the anode plate based on the signal from the resistance sensor.

Abstract: An air cell system provided with emergency air port and an emergency air port is provided. In particular, an emergency port plate is provided between a suction block valve and a blower along air suction line of a fuel cell system or between a humidifier along an air suction line and a discharge block valve along an air discharge line and a wire is connected to the emergency port plate accordingly. Additionally, an operating assembly which enables the air suction line or the air discharge line to be in fluid communication with an external environment by pulling a wire to brake the emergency port plate when the suction block valve or the discharge block valve is not operating properly is also provided to provide a failsafe system for valve failure.

Abstract: A gas supply system that supplies a gas after making confluence of the gas flows from gas containers includes: a supply pressure detector that detects supply pressure of the gas following the confluence; and a controller that permits a gas supply-destination apparatus to be activated if the supply pressure detected after an elapse of a determination time from a start of the gas supply is greater than or equal to a threshold pressure, and that prohibits the apparatus from being activated if the supply pressure is less than the threshold pressure. The controller uses a first determination time as the determination time if it is determined that internal pressures that are the gas pressures in the containers are not imbalanced between the containers, and uses a second determination time that is longer than the first as the determination time if it is determined that the internal pressures are imbalanced.

Abstract: A method and system for preventing gas pressure in a pressure vessel from dropping below a minimum allowable pressure. Pressure readings from a pressure sensor downstream of a pressure regulator are monitored by a processor as they vary within a steady fluctuation band under normal regulated pressure conditions. When the pressure regulator reaches a fully open position in low vessel pressure conditions, the processor detects a drop in the pressure reading to a value below the recent fluctuation band, and recognizes that the pressure is dropping below the regulation pressure value. The processor can use this information to shut off flow of gas from the vessel, thus preventing the vessel from dropping below its minimum allowable pressure, regardless of the actual magnitude of the pressure reading from the sensor—which can vary through a wide range due to tolerances.

Abstract: A method of driving a fuel cell system according to embodiments of the present invention includes supplying a first amount of oxidizer (which is less than a normal amount of oxidizer) to a fuel cell stack while continuously supplying fuel to the fuel cell stack, supplying a second amount of oxidizer (which is more than the normal amount) to the fuel cell stack, and supplying a third amount of oxidizer (which is the normal amount of oxidizer supplied in a normal driving state) to the fuel cell stack.

Abstract: Even in a fuel cell system which performs scavenging processing after the power generation of a fuel cell is stopped, the operation time for when a battery is being operated can be increased. When determining that the condition of running out of gas occurs based on a sensor value of a pressure sensor, a control unit stops the power generation of the fuel cell. The control unit, for example, shortens the time required for scavenging processing and then performs the scavenging processing. On the other hand, when determining that the condition of running out of gas does not occur and when the power generation of the fuel cell should be stopped, the control unit stops the power generation and then performs normal scavenging processing.

Abstract: A gas detection system is configured to detect a preset gas in a predetermined space. The gas detection system includes a gas concentration detector constructed to detect a gas concentration of the preset gas, a recording assembly, a notification module, and a decision module. When the gas concentration detected by the gas concentration detector is higher than a preset first reference value, the decision module controls the notification module to give notice. When the detected gas concentration is higher than a preset second reference value but is lower than the preset first reference value, on the other hand, the decision module controls the notification module to give no notice but record a specific piece of information into the recording assembly. This arrangement of the gas detection system enables the user to readily detect deterioration of a device utilizing a fuel, for example, fuel cells.

Abstract: Fuel cell components provide fuel cells on a flexible sheet that defines a wall of a flexible plenum. An external support structure limits expansion of the plenum in response to forces exerted by a pressurized reactant. The external support structure may comprise a portion of a housing of a portable device. Cathodes of the fuel cells may be accessible from an outside of the flexible sheet and exposed to ambient air while anodes of the fuel cell are accessible from an inside of the flexible sheet and exposed to a fuel, such as hydrogen gas.

Abstract: A fuel cell using a synthetic jet array has a structure in which a plurality of cells are superposed in series and share a manifold for inflow and outflow of air, hydrogen, and coolant. The fuel cell includes an air inflow manifold formed passing through the plurality of cells, a synthetic jet array made up of a plurality of jet generators that are disposed on the air inflow manifold at regular intervals and generate a synthetic jet toward a cathode, and a controller configured to selectively operate the jet generators of the synthetic jet array.

Abstract: A fuel cell system comprises a main body including a first partial header and a fastening point. The main body is adapted to be coupled to a plurality of plates forming a fuel cell stack, allowing a single plate design to be used for multiple fuel cell stack lengths having a large differential of energy requirements, affording a durable alignment mechanism for the fuel cell stack, and providing integration flexibility for components and configurations of the fuel cell system.

Abstract: A fuel cell system may include a fuel cell stack having a header and active area in fluid communication with the header. The fuel cell system may also include a wedge disposed within the header and configured to alter the cross-sectional area of the header along the length of the stack such that, during operation of the stack, a flow velocity of gas through the active area is generally constant.

Abstract: A method including shutting down an electrochemical fuel cell stack wherein anode pressure is controlled according to a stack discharge fuel consumption estimate.

Abstract: A fuel cell membrane-electrode assembly having a fuel electrode and an oxidant electrode has a non-supported-catalyst containing catalyst layer that contains a metal catalyst nanoparticle of 0.3 nm to 100 nm in primary particle diameter that is not supported on a support, and an electrochemically active surface area of the metal catalyst nanoparticle is 10 m2/g to 150 m2/g, and a layer thickness of the non-supported-catalyst containing catalyst layer is less than or equal to 10 ?m.

Abstract: A method for the combined controlled regulation of fuel gas-oxygen carriers of a gas operated energy converter plant (15), in particular of a fuel cell plant, is provided in which the mass or volume through flow of the fuel gas (1) and/or of the oxygen carrier (2) is detected in order to regulate the mixing ratio (r) of fuel gas to oxygen carrier. In the method at least two physical parameters of the fuel gas are additionally determined using a micro thermal sensor (3.1, 3.2), for example, the mass flow and/or volume through flow of the fuel gas and the thermal conductivity or thermal capacity of the fuel gas are determined and a desired value for the mixing ratio is determined from the physical parameters which depends on the fuel gas or on the composition of the fuel gas, and which desired value is used for the regulation of the mixing ratio.

Abstract: A combined generation system according to one embodiment of the present invention comprises: a natural gas synthesizing apparatus for receiving coal and oxygen, generating synthetic gas by a gasifier, and permitting the synthetic gas to pass through a methanation reactor so as to synthesize methane; a fuel cell apparatus for receiving fuel that contains methane from the natural gas synthesizing apparatus and generating electrical energy; and a generating apparatus for producing electrical energy using the fluid discharged from the fuel cell apparatus

Abstract: System and methods for setting pressure limits for an air supply of a fuel cell (“FC”) system are presented. Certain embodiments disclosed herein may allow a FC system to calculate a minimum and a maximum FC stack cathode inlet pressure based on different operating conditions while ensuring that the FC stack receives a desired air flow. Further embodiments disclosed herein may allow a FC system to maintain a cathode inlet air pressure within a range that protects an associated compressor from entering surge and/or overheating conditions.

Abstract: A fuel cell system includes a fuel cell which generates electrical energy by reacting a hydrogen gas from a hydrogen gas supply source and an oxidizing agent gas from an oxidizing agent gas supply source, a hydrogen circulating pump which is provided in a hydrogen circulation path and transfers hydrogen gas of the hydrogen circulation path to the fuel cell, and control means. When the supply of hydrogen gas from the hydrogen gas supply source to the fuel cell is discontinued, the control means discontinues the supply of oxidizing agent gas from the oxidizing agent gas supply source to the fuel cell and activates the hydrogen circulating pump such that electrical energy generated in the fuel cell is supplied to the hydrogen circulating pump.

Abstract: A fuel cell with a recovering unit and a method of driving the same are disclosed. In one embodiment, the fuel cell includes i) an electric generator to generate electricity based on electrochemical reaction, ii) a recovering unit to recover and mix the fuel, unreacted fuel, and gas and water produced by the electrochemical reaction, and supply the mixed fuel to the electric generator, wherein the recovering unit comprises a valve, configured to discharge gas, which is selectively opened and closed depending on the operation of the fuel cell. With this configuration, the gas or the fuel is not introduced into the electric generator, even though the recovering unit is inclined or turned over. Further, even though the fuel cell is not in use for a long time, the mixed fuel is prevented from evaporating through the discharging pipe.

Abstract: A fuel cartridge with which liquid leakage through an air induction hole from a fuel tank is able to be prevented and safety is able to be improved is provided. Switching drive for opening and closing an air induction hole 12 is performed by a valve 13 capable of controlling the switching drive according to a control signal. Thereby, air introduction to a fuel tank 100 containing a fuel is able to be controlled. Thus, for example, at the time of high temperature or fuel disorder, by closing the air induction hole 12 by the valve 13, fuel leakage from the fuel tank through the air induction hole of an existing check valve is able to be prevented, and safety is able to be improved.

Abstract: A system and method for selectively determining whether a freeze purge should be performed at shut-down of a fuel cell stack. The method includes identifying that the vehicle has been keyed off and then determining whether a stack membrane humidification value is less than a predetermined humidification value that identifies the humidification of membranes in fuel cells in the fuel cell stack. If the stack membrane humidification value is not less than the predetermined humidification value, then the method determines if the ambient temperature is below a predetermined ambient temperature, and if so, performs the freeze purge. If the ambient temperature is not below the predetermined ambient temperature, then the method performs a short non-freeze purge of the flow channels in the fuel cell stack. The method determines a wake-up time for a controller for a next time to determine whether a freeze purge should be performed.

Abstract: A power generator includes a fuel container adapted to hold a hydrogen containing fuel. A sliding valve is coupled between a fuel cell and a fuel container. A pressure responsive actuator is coupled to the two stage valve and the fuel container.

Abstract: A sensor cell (1010) for control purposes usable in an assembly (1000) of fuel cells of the type having a membrane electrode assembly (MEA) interposed between an anode gas diffusion layer and a cathode gas diffusion layer, and first and second current collectors coupled to the anode and cathode gas diffusion layers (GDL), respectively. The sensor cell (1010) is preferably coupled so that it shares the negative current collector (1050) with last fuel cell in the in-plane fuel cell assembly (1000), and is short-circuited by a resistor (1070) to provide a voltage signal, indicative of the status of the assembly in operation.

Abstract: Systems and methods to control fuel cell stack pressure through a cathode backpressure valve. A flow offset value is used as a capacitance term during transient operational conditions to account for discrepancies between the stack flow setpoint and the actual stack flow. The capacitance term is based on operational parameters, including stack pressure changes, stack coolant temperature and stack volume. The additional flow produced by the capacitance terms may be fed, along with pressure drop models and a valve position model to provide a more accurate prediction of valve position.

Abstract: Described herein are fuel cell systems that include a cover affecting reactant flow into an electrochemical cell array of the system. The cover includes one or more transport barrier regions and one or more opened regions. The transport barrier regions are in proximity to active regions of the electrochemical cell array.

Abstract: A fuel cell system including a fuel cell stack having a plurality of unit cells is provided. A method of driving the fuel cell stack is also provided. The method may include supplying a fuel to a fuel cell stack, supplying an oxidizer to the fuel cell stack, controlling supply of the fuel and the oxidizer to operate the fuel cell stack, calculating a total operation time of the fuel cell, and/or varying a stack activation period in which the oxidizer is blocked to the fuel cell stack according to the total operation time and a stack activation cycle of which the stack activation period is generated.

Abstract: A fuel gas supply device for supplying fuel gas to a fuel cell stack includes a control valve provided in a fuel gas path connecting a fuel tank and the fuel cell stack, an upstream-side pressure sensor and a downstream-side pressure sensor for detecting an upstream-side pressure and a downstream-side pressure, and a programmable controller. The programmable controller calculates a required opening based on a target fuel gas pressure and the downstream-side pressure and calculates an opening time and a closing time based on the required opening and the upstream-side pressure, or calculates an opening time and a closing time based on the target fuel gas pressure and the downstream-side pressure and calculates a required opening based on the opening time and the upstream-side pressure, and controls the control valve using the calculated required opening, opening time and closing time.

Abstract: A method for optimizing fuel feed of a fuel cell stack catalytic electrode, the fuel cell stack containing a cell comprising a proton exchange membrane located between said catalytic electrode and another electrode, operating in superstoichiometric mode, said fuel comprising a carbonyl-containing polluting agent compound reacting on said catalytic electrode, comprises: defining a reference voltage for said cell when fed with a fuel exempt from polluting agent; defining a threshold voltage corresponding to a preset operating voltage of said cell as a percentage of reference voltage; defining a calibration curve for given operating conditions, relating threshold voltage to flow rate of polluting agent and allowing a first parameter of flow rate of polluting agent to be defined; detecting polluting agent to define a second parameter corresponding to content of polluting agent present in said fuel; and determining a maximum stoichiometry coefficient for said fuel stream, depending on said two parameters.

Abstract: A system and method for identifying leaks in a cathode sub-system of a fuel cell system. An air flow meter is provided up-stream of a compressor and monitors the air flowing into the compressor. When an air leakage diagnostic is commanded, a fuel cell stack by-pass valve and back-pressure valve are closed so that no air flows through or around the stack, and the recirculation valve is opened so that the air flows around the compressor. By knowing the leakage through the by-pass valve and the back-pressure valve, any flow above those values measured by the air flow meter gives an indication of air leakage out of the cathode sub-system components.

Abstract: A gas turbine includes a compressor and a combustor; a SOFC having a cathode and an anode; a first compression air supply line supplying compression air to the combustor; a second compression air supply line supplying compression air to the cathode; an exhaust air supply line supplying exhaust air discharged from the cathode to the combustor; a first fuel gas supply line supplying a fuel gas to the combustor; a second fuel gas supply line supplying a fuel gas to the anode; a fuel gas supply ratio change unit capable of changing a supply ratio of the fuel gas supplied to the combustor and the fuel gas supplied to the anode; an exhaust fuel gas supply line supplying an exhaust fuel gas discharged from the anode to the combustor; and a controller performing open-close control of the control valves and according to an operation state of the SOFC.

Abstract: Disclosed herein are systems and methods for monitoring and controlling a flow of air within a fuel cell stack. The fuel cell stack may include an air supply path to conduct a flow of air through the fuel cell. Sensors may be configured to determine parameters associated with the air supply path, such as pressure, flow rate, etc. A modeling system may further be configured to determine a modeled parameter associated with the air supply path. A control system may receive input from the one or more sensors and the modeling system to generate a baseline based on the measured parameter and the modeled parameter, determine a difference between the measured parameter and the modeled parameter, determine a change of the difference with respect to the baseline, determine that the change satisfies a criterion, and selectively implement a corrective action based upon satisfaction of the criterion.

Abstract: The present invention provides a hybrid fuel cell system that is configured to determine if an idle stop condition has been satisfied during a normal operation mode of the hybrid fuel cell system, cut off air supply to a fuel cell to stop power generation of the fuel cell and reduce a voltage which the fuel cell outputs in response to determining that the idle stop condition has been satisfied. The voltage of a bidirectional converter, connected between a battery and a bus terminal is reduced and the output of the fuel cell is controlled, based on a first predetermined value and maintained at that first predetermined value. Subsequently, the battery is charged via the output current of the fuel cell generated by maintaining the reduced voltage of the bidirectional converter.

Abstract: A fuel cell system for generating a hydrogen test pulse includes a fuel cell stack having an anode inlet in fluid communication with a hydrogen source via a fuel spending line, a cathode inlet in fluid communication with an oxidant source, and an anode outlet and a cathode outlet in fluid communication with an exhaust line. An electric pressure regulator is in fluid communication with the fuel spending line. An overpressure valve is in fluid communication with an overpressure line, which is in fluid communication with the fuel spending line between the electric pressure regulator and the fuel cell stack. A hydrogen sensor is in communication with the exhaust line, and is configured to measure the hydrogen test pulse.

Abstract: A valve includes a cap, a diaphragm defining a movable portion, a valve housing, and a valve portion. An inlet port through which fluid flows into a valve chamber, an outlet port through which the fluid flows out from the valve chamber, and a placement portion on which a peripheral edge portion of the diaphragm is placed are provided in the valve housing. The diaphragm includes a peripheral edge portion, a center portion, a connecting portion connecting the peripheral edge portion and the center portion, and a pusher. The connecting portion has a wave shape from the peripheral edge portion side toward the center portion side such that the connecting portion first projects to a valve body portion side, and next projects to the cap side.

Abstract: Systems and methods to mitigate surge conditions in a compressor of a vehicle fuel cell system. A first surge mitigation strategy regulates a cathode backpressure valve, if the compressor is operating at or above a threshold speed. A second surge mitigation strategy regulates a recirculation valve if the compressor is operating below the threshold speed. In one form, a feedback-based control may be used as part of a larger feedforward-based control strategy such that the mitigation is part of a reactive control strategy. The strategy may additionally be implemented in a processor-based controller.

Abstract: A large, scalable SOFC system based on modules, which may be connected in series on the cathode gas side. The fuel cell stacks are aligned side by side and assembled into a stack module with cathode inlets on one face of the module and the cathode outlets on the other face of the module. The stack modules are serially connected in a simple manner by placing the stack modules one after the other, so that the outlet face of the first module faces the inlet face of the second module and so on. In the chamber between two stack modules, the air is cooled for example by addition of cold quench air or by a heat exchanger. This offers compactness, simple stack/system interface and improved system performance. The modules are designed for manufacturability, well-balanced heat management and high fuel utilization.

Abstract: In one or more embodiments, a fuel cell system includes a fuel cell stack including an anode and a cathode, a first conduit positioned to supply oxygen to the cathode, a second conduit positioned to supply hydrogen to the anode, and a third conduit positioned separate from the first and second conduits and to supply oxygen to the second conduit. The third conduit may be positioned to supply oxygen from the first conduit to the second conduit.

Abstract: An apparatus for placing a fuel cell stack in a standby mode is provided. The apparatus comprises a compressor, a fuel cell stack, a cathode valve and a controller. The compressor is operably coupled to an air induction system for providing a cathode stream. The fuel cell stack provides electrical power to a load in response to the cathode stream. The cathode valve is operably coupled to an outlet of the fuel cell stack for controlling a flow of the cathode stream to the fuel cell stack. The controller is configured to receive a power request amount for the load and to compare the power request amount to a predetermined amount.

Abstract: The present invention provides a fuel cell hybrid system having a multi-stack structure, which maintains the voltage of a fuel cell at a level lower than that of an electricity storage means (supercapacitor) during regenerative braking so that the fuel cell does not unnecessarily charge the electricity storage means, thereby increasing the amount of recovered energy and improving fuel efficiency.

Abstract: A fuel cell system includes, an oxidant feeder configured to supply an oxidant to a fuel cell, an oxidant passage which communicates with the fuel cell, a bypass passage which branches from the oxidant passage and along which part of the oxidant flows so as to bypass the fuel cell, a bypass valve which is provided in the bypass passage, an oxidant quantity-of-flow control unit which is configured to supply the quantity of flow of the oxidant corresponding to an amount of electricity required by the fuel cell, and an oxidant quantity-of-flow control unit for a sound vibration mode configured to supply a constant quantity of flow of the oxidant, and further includes a bypass valve control unit configured to control the bypass valve according to a requirement of the fuel cell when the oxidant quantity-of-flow control unit for the sound vibration mode controls the oxidant feeder.

Abstract: A fuel cell power production system and method for supplying power to a load, comprising a high-temperature fuel cell including an anode compartment, adapted to receive fuel from a fuel supply path and to output anode exhaust, and a cathode compartment adapted to receive oxidant gas and to output cathode exhaust, a water transfer assembly for transferring water in the anode exhaust to the fuel supply path and for outputting water-separated anode exhaust; and a hydrogen utilization device adapted to receive oxidant gas and one of the water-separated anode exhaust and gas derived from the water-separated anode exhaust and to output hydrogen utilization device exhaust including oxidant gas, wherein the hydrogen utilization device exhaust is used to provide oxidant gas to said cathode compartment.

Abstract: A fuel cell apparatus includes a fuel cell generating electric power, and including a fuel electrode which includes an anode catalyst, which is disposed in one side of an electrolyte membrane, which is supplied with liquid fuel, and which discharges gas generated by a chemical reaction accelerated by the anode catalyst, and an oxidizing agent electrode which includes a cathode catalyst, which is disposed in the other side of the electrolyte membrane, and which is supplied with air, and a control unit controlling a load applied to the fuel cell. The control unit increases the load in at least one of two cases, one case being when electric power generated by the fuel cell lowers below a predetermined reference value and another case being at predetermined time intervals, and stops the increase of the load after elapsing a predetermined time period from the start of the increase of the load.

Abstract: A fuel cell system having an adsorber placed in an air supply path to an air electrode of a fuel cell and receiving a chemical filter for adsorbing impurities contained in air; measurement means for measuring the amount per unit time of air having passed the adsorber; detection means for detecting the density of impurities contained in the air, whose volume has been measured by the measurement means, before it enters the adsorber; estimation means for estimating, based on the amount of the air, the density of the impurities, and adsorption efficiency of the chemical filter, the amount of the impurities adsorbed per unit time by the chemical filter; and output control means for causing a signal to output when an accumulated value of the amount of the impurity exceeds a predetermined level.

Abstract: A cathode for use in a direct oxidation fuel cell (DOFC) comprises a gas diffusion medium (GDM) including a backing layer and a microporous layer comprising a fluoropolymer and an electrically conductive material, wherein loading of the fluoropolymer in the microporous layer is in the range from about 10 to about 60 wt. %. In use, a concentrated solution of a liquid fuel is supplied to an anode and an oxidant to the cathode of the fuel cell, and the fuel cell may be operated at a low oxidant stoichiometry ?c not greater than about 2.5.

Abstract: A system and method for controlling hydrogen gas flow to an anode side of a fuel cell stack using a pressure regulator in the event that an injector that normally injects the hydrogen gas into the fuel cell stack has failed in a stuck open position. During normal operation, the control of the injector is determined based on the pressure of an anode sub-system and the position of the pressure regulator is determined based on a supply pressure between the pressure regulator and the injector. If it is determined that the injector is stuck in an open position, then the position of the pressure regulator is controlled to the anode pressure instead of the supply pressure. If the pressure regulator is an electrical pressure regulator, then it is pulsed to mimic normal system operation. Alternately, another valve, such as a shut-off valve, can be employed to provide the flow pulsing.