Abstract: A solid oxide fuel cell capable of maintaining performance over a long time period by appropriately changing fuel cell module operating conditions. The present invention is a solid oxide fuel cell (1), having a fuel cell module (2), a fuel supply device (38), an oxidant gas supply device (45), and a controller (110) for controlling the amount of fuel supplied from the fuel supply device; the controller is furnished with a degradation determining circuit (110a) for determining degradation in the fuel cell module and a degradation response circuit (110b) for changing fuel cell module operating conditions based on the degradation determination by the degradation determining circuit; the degradation determination stores fuel cell module operating results arising from the operating conditions changed by the degradation response circuit, and executes further degradation determination based on the stored operating results.

Abstract: A gas detection system functions to detect a specific gas present in a certain space. The gas detection system includes a gas concentration detector arranged to detect concentration of the specific gas as a gas concentration. The gas detection system also has a determination module configured to determine whether the gas concentration detected by the gas concentration detector exceeds a set threshold value. In response to input of a checking instruction for checking up the gas concentration detector into the determination module, the determination module uses a threshold value for checkup purpose, in place of the set threshold value. This arrangement effectively enhances the convenience in the process of checking up the gas concentration detector.

Abstract: Methods and systems for operating a fuel cell stack having a fuel exhaust stream and a vessel downstream of the fuel cell stack fluidly connected to the fuel exhaust stream are provided. In one embodiment, the method comprises displacing substantially all residual gas in the vessel by providing at least a portion of the fuel exhaust stream to the vessel, and isolating the vessel from the fuel cell stack after the fuel exhaust stream displaces substantially all residual gas in the vessel. At least one bleed down characteristic is determined as fuel exhaust within the vessel is released through an orifice, and an operating condition of the fuel cell stack is set or determined based on the at least one bleed down characteristic. In a specific embodiment, the hydrogen concentration in the fuel exhaust is determined based on the at least one bleed down characteristic.

Abstract: A fuel cell stack includes a heat exchange unit that performs heat exchange between a gas mixture containing source hydrogen and a circulating gas and cooling water used for controlling the temperature of the fuel cell stack. A system controller adjusts the temperature of the cooling water by controlling a temperature control unit on the basis of the temperature of source hydrogen flowing into a junction at which the source hydrogen and a circulating gas are mixed such that the temperature of a source/recirculated hydrogen mixture that is mixed at the junction and that is supplied to the fuel cell stack is kept within a managed temperature range.

Abstract: The present invention provides a composite separator for a polymer electrolyte membrane fuel cell (PEMFC) and a method for manufacturing the same, in which a graphite foil prepared by compressing expanded graphite is stacked on a carbon fiber-reinforced composite prepreg or a mixed solution prepared by mixing graphite flake and powder with a resin solvent is applied to the cured composite prepreg such that a graphite layer is integrally molded on the outermost end of the separator.

Abstract: A method of using a proton exchange membrane fuel cell, composed of a polymer membrane and electrodes present on either side of the membrane, includes at least one step of reversing the functioning of the cell during use.

Abstract: Disclosed herein is a fuel supply comprising a compressed gas chamber and liquid fuel chamber. A pressure regulator connects the compressed gas chamber to the liquid fuel chamber. The pressure regulator is capable of taking a high pressure input from the compressed gas chamber and providing a substantially constant lower output pressure to the liquid fuel chamber. The pressure of the compressed gas chamber can decrease over time, but the pressure that urges liquid fuel out of the liquid fuel chamber remains substantially at the same level.

Abstract: A pump has a shaft, an impeller arranged on the shaft, and a labyrinth seal which is arranged between stationary and moving parts of the pump. A plurality of blades are arranged on the rotor and a labyrinth seal extends at least between the shaft and a rear portion of the blades. A gap in the labyrinth seal is designed such that liquid water can be actively carried away, with the labyrinth seal for this purpose being designed at least in places with a channel in the form of a spiral and/or a staircase. The invention also relates to a fuel cell system having such a pump.

Abstract: Provided is a fuel cell system including: a fuel cell which generates power by an electrochemical reaction between an oxidant gas supplied to an oxidant gas flow path and a fuel gas supplied to a fuel gas flow path; and a controller which adjusts an amount of the oxidant gas supplied to the fuel cell and a voltage of the fuel cell. The controller has an obstruction degree determining unit which determines a degree of obstruction of the oxidant gas flow path based on a stoichiometric ratio of the oxidant gas and the voltage of the fuel cell during a low-efficiency operation in which the stoichiometric ratio of the oxidant gas is reduced from the stoichiometric ratio of the oxidant gas during a normal operation and heat discharged from the fuel cell is increased from that during the normal operation. This improves stability of the low-efficiency operation of the fuel cell system.

Abstract: A system for delivering an input fuel stream to a fuel cell stack to generate electrical current and to discharge an unused fuel stream is provided. A supply produces a supply fuel stream. An ejector combines a purged fuel stream and the supply fuel stream and controls the flow of the input fuel stream to the fuel cell stack. A purging arrangement receives the unused fuel stream which includes impurities and purges the impurities from the unused fuel stream to generate the purged fuel stream. A bypass valve is capable of delivering the purged fuel stream to the ejector. A blower is capable of delivering the purged fuel stream to the ejector. A controller controls one of the bypass valve and the blower for delivering the purged fuel stream to the ejector based on the amount of electrical current generated by the fuel cell stack.

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 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: The degree of dryness in a fuel cell can be judged more accurately. A system has: an impedance calculation part that calculates an impedance of a fuel cell, extracts from the calculated impedance a high-frequency impedance which is an impedance in a high frequency range and a low-frequency impedance which is an impedance in a low frequency range, and subtracts the high-frequency impedance from the low-frequency impedance to calculate a differential impedance; a water content calculation part that calculates the water content of an electrolyte membrane using the high-frequency impedance and calculates the water content of a catalyst layer using the differential impedance; and a water content control part that performs water content recovery processing to increase the water content of the catalyst layer if the water content of the catalyst layer is smaller than a predetermined water content.

Abstract: A fuel cell system including a fuel cell stack having a plurality of fuel cells, the fuel cell stack including an anode supply manifold and an anode exhaust manifold, a first valve in fluid communication with at least one of the anode supply manifold and the anode exhaust manifold, wherein the first valve includes an inlet for receiving a fluid flow and an outlet for exhausting a fluid, a sensor for measuring at least a fluid pressure at the inlet and the outlet of the first valve, wherein the sensor generates a sensor signal representing the pressure measurement, and a processor for receiving the sensor signal, analyzing the sensor signal, and determining a composition of a fluid in the fuel cell system based upon the analysis of the sensor signal.

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 fuel cell system includes: a fuel cell having an anode and a cathode; an oxidant gas flowpath supplying the oxidant gas to the fuel cell and discharging the oxidant gas from the fuel cell; a first shut-off valve disposed upstream from the fuel cell and having a first valve body; a second shut-off valve disposed downstream from the fuel cell and having a second valve body; a cathode control unit for sealing the cathode; and a scavenging unit for scavenging the anode by supplying the oxidant gas to the anode, wherein the cathode control unit, before scavenging the anode by using the scavenging unit, unseals the cathode by opening the first shut-off valve and the second shut-off valve. The fuel cell system is capable of preventing the valve bodies pressed against seat sections from being frozen even below the freezing temperature, and capable of avoiding a situation unable to restart a turned-off state of the fuel cell system.

Abstract: A fuel cell system includes a fuel cell which generates electric power using supplied reactive gases; a load control device for controlling a load applied to the fuel cell; a voltage measuring device for measuring a voltage generated by the fuel cell; a fuel cell driving control device for controlling at least a supply of the reactive gases to the fuel cell; and a voltage variation rate obtaining device for obtaining a rate of variation in the voltage generated by the fuel cell when the load is varied. The fuel cell driving control device is controlled based on the rate of variation in the generated voltage obtained by the voltage variation rate obtaining device. The voltage variation rate being obtained when the generated voltage increases. The load being varied by applying momentarily a load to the fuel cell when the voltage variation rate is obtained.

Abstract: An electrochemical device (such as a battery) includes at least one electrode having a fluid surface and one or more sensors configured to detect an operating condition of the device. Fluid-directing structures may modulate flow or retain fluid in response to the sensors. An electrolyte within the device may also include an ion-transport fluid, for example infiltrated into a porous solid support.

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: 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 control device of a fuel cell system sets a required output of a fuel cell stack that is required according to a present power demand and predicts the required output and the current according to the temperature of the fuel cell stack from a predetermined output state map that is preset. The control device sets an operation state quantity according to the predicted current and the temperature of the fuel cell stack from a predetermined operation state quantity map that is preset. The control device includes at least one of a pressure at an air supply port of air that is supplied to the cathode electrode of the fuel cell stack, a utilization rate of the air at the cathode electrode, a flow rate of a cooling medium that cools the fuel cell stack, and humidity of the air at the air supply port as the operation state quantity.

Abstract: In a fuel cell system, it is possible to suppress fixation of a fluid circulating device arranged in a fluid passage connected to a fuel cell main body. The fuel cell system is provided with a fuel cell stack, a system main body having respective elements for supplying a fuel gas and respective elements for supplying an oxidizing gas, and a control device. The control device includes a fluid circulating device drive processing unit having a function to forcibly drive the fluid circulating device after determining, based on a judgment related to one or more of a non-use time, an operation state of the system main body, a membrane impedance state of a fuel cell, a temperature of the fuel cell stack, and a background noise, whether or not forced driving to suppress sticking of the fluid circulating device is preferable at that time.

Abstract: An electrochemical device (such as a battery) includes at least one electrode having a fluid surface and one or more sensors configured to detect an operating condition of the device. Fluid-directing structures may modulate flow or retain fluid in response to the sensors. An electrolyte within the device may also include an ion-transport fluid, for example infiltrated into a porous solid support.

Abstract: Fuel cell systems and methods having reduced volumetric requirements are described. The systems include, among other things, an enclosed region formed by the bonding of a fuel cell layer with a fluid manifold. The enclosed region transforms into a fluid plenum when, for example, a fluid exiting a manifold outlet pressurizes the enclosed region causing one or more portions of the fuel cell layer and/or the fluid manifold to deform away from each other.

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: A fuel cell system that is able to perform power generation more stably than in the past regardless of external environment is provided. Based on a temperature of a power generation section detected by a temperature detection section, a supply amount of a liquid fuel from a fuel pump is adjusted, and therefore control in which the temperature of the power generation section becomes constant is performed. In addition, a fuel cell system that is able to perform power generation in a vaporization supply type fuel cell more stably than in the past is provided. A level of a power generation voltage supplied from the power generation section is raised by a boost circuit. In a control section, operation of the boost circuit is controlled using a given control table, and therefore control is performed on an output voltage and an output current supplied from the boost circuit to a load.

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: According to one embodiment, a fuel cell includes an electric-power generator, a fuel distribution mechanism, and a pump. The electric-power generator includes a membrane electrode assembly including an anode, a cathode, and an electrolytic membrane. The fuel distribution mechanism includes a container and a thin tube. The container includes a fuel discharge surface, and contains the electric-power generator inside. The thin tube is formed in the container in a manner that a fuel outlet and a fuel inlet communicate with each other. The pump is connected directly to the fuel inlet.

Abstract: A fuel cell power plant includes a cell stack assembly having an anode and a cathode. A component is arranged in fluid connection with at least one of the anode and cathode. The component has a first shut-down cooling rate. A heat exchanger is arranged in fluid communication with and between the component and one of the anode and cathode. The heat exchanger has a second shut-down cooling rate greater than the first shut-down cooling rate. Water vapor within the fuel cell power plant outside of the cell stack assembly will condense and freeze in the heat exchanger rather than the component, avoiding malfunction of the component upon start-up in below freezing environments.

Abstract: The fuel cell system is simplified and made more compact while providing the favorable recirculation of hydrogen-containing off-gas regardless of the increase or decrease in its flow rate. The fuel cell system is provided with: a cell unit that generates electricity by means of separating hydrogen-containing gas and oxygen-containing gas from each other while placing in flow contact to each other; and a recirculation mechanism for recirculating to the cell unit hydrogen-containing off-gas discharged from the cell unit. The fuel cell system has a flow rate determination unit that determines whether or not the hydrogen-containing gas fed to the cell unit is less than a predetermined flow rate; and a gas feeding pressure varying mechanism that cause the pressure of the hydrogen-containing gas to vary to increase and decrease when it is determined that the hydrogen-containing gas fed to the cell unit is less than the predetermined flow quantity.

Abstract: A fuel cell system that determines the concentration of hydrogen gas in an anode loop. The fuel cell system includes at least one fuel cell, an anode inlet, an anode outlet, an anode loop, a source of hydrogen gas and an injector for injecting the hydrogen gas. First and second pressure sensors are provided in the anode loop and are spaced a known distance from each other. A controller responsive to the output signals from the first and second pressure sensors filters the sensor signals from the first and second pressure sensors and determines the concentration of hydrogen gas in the anode loop based on the time difference between the filtered sensor signal from the first pressure sensor and the filtered sensor signal from the second pressure sensor.

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 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 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 system comprising a generation chamber, a plurality of fuel cells arranged in the generation chamber, fuel gas feeding means for feeding a fuel gas to the fuel cells, oxygen-containing gas feeding means for feeding an oxygen-containing gas to the fuel cells, power converter means for converting the DC output of the fuel cells into an alternating current, power control means for controlling the electric power output to the power converter means from the fuel cells, and generation control means for controlling the flow rate of the fuel gas fed to the fuel cells and the flow rate of the oxygen-containing gas fed to the fuel cells. A fuel gas buffer amount specific to the fuel cells is not smaller than a fuel gas amount that is needed within a maximum period of increase-needing time that is necessary until the flow rate of the fuel gas increases to a required amount when the amount of increase in the flow rate of the fuel gas is set to be a maximum.

Abstract: A fuel cell system for a vehicle includes a fuel cell, a fuel supply device, an oxidizer supply device, an anode potential measuring device, and a discharge controller. The anode potential measuring device is configured to measure an anode potential of an anode. The discharge controller is configured to control discharge of electric current from the fuel cell as part of a process of stopping the fuel cell during idling of the vehicle. When receiving idle stop permission for the fuel cell, the discharge controller determines whether the fuel cell is permitted to discharge. When the anode potential is equal to or lower than a predetermined threshold value, the discharge controller permits the fuel cell to discharge. When the anode potential is higher than the predetermined threshold value, the discharge controller does not permit the fuel cell to discharge.

Abstract: A fuel cell system including a fuel cell, a reformer, a combustor that heats the reformer using anode off-gas of the fuel cell as a fuel, and a ratio controller that controls a ratio of a combustion component supplied to the combustor in accordance with a temperature distribution in a gas flow direction inside the combustor.

Abstract: A fuel cell system of the present invention includes a fuel cell, a supply channel which supplies, to the fuel cell, a fuel gas supplied from a fuel supply source, a variable gas supply device which adjusts a gas state on an upstream side of this supply channel to supply the gas to a downstream side, a control section which performs PI control of a gas supply command amount with respect to the variable gas supply device, and an abnormality judgment section to judge whether or not the variable gas supply device is abnormal. The controller uses, as a part of a correction term of the PI control, a learning term constituted by integrating an I term only in a case where an operation state of the fuel cell satisfies predetermined learning allowable conditions. The abnormality judgment section judges based on this learning term whether or not the variable gas supply device is abnormal.

Abstract: Provided is a fuel cell system capable of making a shift of an operation state while optically controlling an output voltage and an output voltage of a fuel cell. When an ECU judges that the time when an operation should be shifted from a low-efficiency operation to a normal operation has come, the ECU performs, as preprocessing prior to a shift to a ?V control, processing of increasing an oxidant gas supplied to a fuel cell stack by a predetermined amount. After this processing, the ECU detects output power, calculates an output power deviation, and then compares the output power deviation with a set deviation threshold. When the output power deviation exceeds the deviation threshold, the ECU carries out the ?V control, and then carries out an I-V control. Meanwhile, when the output power deviation does not exceed the deviation threshold, the ECU judges that the time when the ?V control is carried out has not come yet, and automatically starts the I-V control without carrying out the ?V control.

Abstract: A fuel cell system includes a fuel cell stack for receiving a supplied reactant gas to generate a power; an air compressor for removing moisture remaining in the fuel cell stack during the stop of the power generation; a secondary cell for supplying an operative power to the air compressor; and a controller for controlling the balance of water flowing into and out of the fuel cell stack so that a time required to remove the moisture remaining in the fuel cell stack by the air compressor is substantially constant.

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.

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 power generating system includes a fuel cell, an exhausted oxidized gas line to which exhausted oxidized gas is discharged from the fuel cell, a gas turbine having a combustor configured to burn an exhausted oxidized gas passing through the exhausted oxidized gas line together with a fuel gas, a temperature detection unit configured to detect a temperature of the exhausted oxidized gas discharged from the fuel cell or a temperature of the exhausted oxidized gas passing through the exhausted oxidized gas line, a fluid supply unit configured to supply a fluid to the exhausted oxidized gas line, and a control unit configured to control an amount of the fluid to be supplied from the fluid supply unit to the exhausted oxidized gas line based on a detection result in the temperature detection unit.

Abstract: According to a first aspect, the present invention relates to a method of controlling a fuel cell, comprising a step of controlling the fuel cell electric efficiency per unit of active surface area by checking and/or adjusting the current density produced in the fuel cell per unit of active surface area. According to another aspect, the present invention concerns a fuel cell suitable for obtaining an electric power output, which comprises, among the other things, control means of the electric efficiency of the fuel cell including means suitable for checking and/or adjusting the current density produced in the fuel cell per unit of active surface area.

Abstract: A fuel cell system having a fuel cell generator and a fuel cartridge that is removably attachable to the fuel cell generator is disclosed. The fuel cartridge includes a housing having a port, a normally closed valve disposed in the housing that gates fuel emerging from the port, the valve having a poppet that modulates opening of the valve, the poppet having a control surface. The fuel cell generator has a moveable pintle coupled to the poppet, and the moveable pintle is operative over a range of motion which causes the poppet to move between a closed state and at least one open state.

Abstract: A fuel cell power generation system including a fuel cell, a fuel generator, an oxidizing gas supply device, an output controller, an open-close mechanism, and a controller. The controller is configured such that in a stop process, the controller controls the output controller to stop supplying the electric power to an external load; controls the oxidizing gas supply device to stop supplying an oxidizing gas and controls the open-close mechanism to close a passage upstream from an oxidizing gas channel; after the passage upstream from the oxidizing gas channel is closed, stops a raw material gas supply device and a water supply device when a predetermined period has elapsed, during which period a gas in the oxidizing gas channel is replaced by a fuel gas.

Abstract: A method that employs a model based approach to determine a maximum anode pressure set-point based on existing airflow in the exhaust gas line. This approach maximizes anode flow channel velocity during bleed events while meeting the hydrogen emission constraint, which in turn increases the amount of water purged from the anode flow channels to increase stack stability.

Abstract: The invention provides a fuel supply control system for fuel cells, controlling fuel concentration in a fuel unit. The fuel supply control system comprises a first thermal meter detecting a system temperature of the fuel cell, a fuel supply device comprising a fuel tank storing highly concentrated fuel and a fuel deliver device delivering fuel from the fuel tank to the fuel unit to adjust fuel concentration thereof, and a controller calculating a difference between a predetermined and an environmental temperature, generating a first velocity by adjusting the predetermined fuel supply velocity according to the temperature difference, and setting the delivery velocity of the fuel delivering device according to the first velocity.