Abstract: A fuel cell system includes a fuel cell; a circulating system that circulates and supplies fuel off-gas discharged from the fuel cell to the fuel cell; a pump that pumps a fluid in the circulating system; a discharge valve through which the fluid in the circulating system is discharged to the outside; and a control device that controls the pump and the discharge valve. If operation of the fuel cell is started in a cold environment, the control device executes a control to start power generation in the fuel cell for a first period before activating the pump and executes a control to drive the pump while the discharge valve is closed for a second period.

Abstract: Various embodiments enable the operation of fuel cell system support equipment using variable frequency drives and power from fuel cells and/or grid power sources.

Abstract: The invention relates to a method for operating a fuel cell (2), which is to be implemented by means of a control computer (10) that drives the level of current generated by the cells of the fuel cell, said fuel cell including a means for tracking the temperature of the cells, said method being characterized in that it comprises the following steps: when starting the operation of the fuel cell, if the temperature of the cells is at a sufficiently low level, particularly less than 0° C., driving a series of cycles of current intervals including, alternately for each cycle, a low non-zero current (Imin), and then a current interval comprising raising and lowering the strength of the current at programmed speeds.

Abstract: A system and method for controlling the speed of a compressor in the event that an airflow meter that measures the airflow from the compressor to the cathode input of the stack fails. When a failure of the airflow meter is detected, an algorithm first deactivates the primary feedback control algorithms used to control cathode pressure and flow, and sets the cathode exhaust valve to a fully open position. The speed of the compressor is controlled by an open loop set-point and the airflow from the compressor is estimated by a model using compressor discharge pressure and the compressor speed. The cathode by-pass valve position is determined by calculating the difference between the requested cathode airflow and the modeled compressor output flow. The position of the by-pass valve is then adjusted using the valve characteristics and the compressor discharge pressure. The estimated airflow to the stack is used to control the maximum stack current.

Abstract: A method to control the heat balance of fuel cell stacks in a fuel cell system, the fuel cell system including at least one fuel cell unit including fuel cell stacks, whose fuel cells include an anode side and a cathode side, as well as an electrolyte interposed therebetween, and a recuperator unit for heat exchange for preheating a supply flow of the cathode side. In the method, a desired portion is separated from the fuel exhaust flow coming from the anode side and adapted to be mixed with the cathode side exit flow before said recuperator unit. Also provided is a fuel cell system implementing the method.

Abstract: Embodiments relate to a fuel cell system. In an embodiment, the fuel cell system includes advanced leak test capabilities. In another embodiment, the fuel cell system includes a system to bypass one or more separation units while permitting the fuel cell system to continue to produce electricity. In another embodiment, the fuel cell system includes an alignment system that permits ease of alignment when a fuel cell module is installed proximate a fuel processing module. In another embodiment, the fuel cell system includes a system of supplying auxiliary fuel from a mobile auxiliary fuel supply. In an embodiment, one or more or all of these embodiments may be practiced together in combination.

Abstract: A fuel cell system (1) which includes: a fuel cell (2) to be supplied with a gas for power generation, the gas unused for the power generation to be discharged out of the fuel cell (2); a circulation flow path (8) through which the discharged gas is resupplied to the fuel cell (2); a variable flow rate circulation pump (6) for circulating the gas through the circulation flow path (8); a valve (7) for discharging the gas in the circulation flow path (8) to the outside thereof; a voltage sensor (22) for measuring voltage of the fuel cell (2); and a controller (32) for controlling the circulation pump (6) and the valve (7). The circulation pump (6) and the valve (7) are controlled based on the voltage (CV) measured by the voltage sensor (22).

Abstract: The present disclosure is directed to systems and methods for independently controlling the operation of fuel cell stacks and to fuel cell systems incorporating the same. These systems and methods may include providing a fuel cell system including a plurality of fuel cell stacks and at least a first energy storage device and controlling the operation of the plurality of fuel cell stacks based at least in part on a variable associated with the fuel cell system and/or an energy consuming device. These systems and methods may further include beginning production of electrical output from the fuel cell system responsive to a start condition, initiating production of electrical output from the plurality of fuel cell stacks responsive to a plurality of stack start conditions, and ceasing the production of electrical output from the fuel cell stacks responsive to at least a first stack stop condition.

Abstract: A fuel cell system is disclosed, wherein the fuel cell system is heated by a fluid during a starting operation to mitigate against vapor condensation and ice formation in a fuel cell assembly and to decrease a warm up time of the fuel cell system.

Abstract: Disclosed is a system and method for operating a fuel cell system, which improves durability of a fuel cell stack by purging oxygen diffusing into an air electrode of the fuel cell stack while the fuel cell vehicle is parking. That is, the present invention provides a system and method for operating a fuel cell system, which prevents an interface between oxygen and hydrogen from forming at an anode by periodically supplying hydrogen to a cathode to purge oxygen when the oxygen concentration is greater than a predetermined level to prevent oxygen in the air from diffusing into the cathode while parking the fuel cell vehicle, thus preventing durability of a membrane electrode assembly of a fuel cell stack from deteriorating.

Abstract: A controller (81) in a fuel cell system (1A) operates a fuel cell (60) in a normal mode or in a special mode which is switched by the controller (81); in which in the normal mode, the fuel cell (60) is operated so as to satisfy at least one of a first operation condition and a second operation condition, the first operation condition being a condition in which an operation time of the fuel cell per unit period is equal to or shorter than a unit allowable operation time defined based on a total durable operation time of at least one of the fuel cell and the auxiliary device, the second operation condition being a condition in which the number of times of operation of the fuel cell per unit time is equal to or less than a unit allowable number of times of operation defined based on a total durable number of times of operation of at least one of the fuel cell and the auxiliary device, and in the special mode, the fuel cell (60) is operated without being limited by at least one of the first operation condition an

Abstract: A power generation system includes: an air intake passage; a fuel cell system that includes a fuel cell; a case configured to house the fuel cell, a ventilator (air supply unit), and an air intake temperature detector configured to detect a temperature of the intake air supplied to the case; a combustion device that includes a combustor; an exhaust gas passage configured to discharge a flue gas generated in the combustion device to the outside; and a controller. The air intake passage and the exhaust gas passage are configured to allow heat exchange to occur between media flowing through the passages. The controller causes the combustion device to operate when the fuel cell system is activated and the temperature detected by the air intake temperature detector is equal to or lower than a first predetermined temperature.

Abstract: There is provided a vehicular fuel cell system. A fuel gas supply path is configured to supply fuel gas from a fuel gas container to a fuel cell stack. A primary decompression valve is disposed on the fuel gas supply path. A secondary decompression valve is disposed on the fuel gas supply path at a downstream side of the primary decompression valve. The secondary decompression valve is fixed to the fuel cell stack.

Abstract: A system and method for controlling the speed of a compressor that provides air to the cathode side of a fuel cell stack in the event that a cathode by-pass valve fails. If a by-pass valve failure is detected, a failure algorithm first disengages the normal flow and pressure algorithms used to control the airflow to the cathode side of the stack. Next, the failure algorithm opens the cathode exhaust gas valve to its fully opened position. Then, in response to a stack power request, the compressor control will be put in an open-loop control where a look-up table is used to provide a particular compressor speed for a power request. An airflow meter will measure the airflow to the stack, and the stack current will be limited based on that airflow.

Abstract: An apparatus for heating a fuel cell assembly is disclosed, wherein a means for heating is disposed in a manifold of the fuel cell assembly and the means for heating causes the manifold to be heated to militate against fluid condensation and ice formation in the fuel cell assembly.

Abstract: A system and method for quickly heating a fuel cell stack at fuel cell system start-up. The fuel cell system includes a three-way valve positioned in the anode exhaust that selectively directs the anode exhaust gases to the cathode input of the fuel cell stack so that hydrogen in the anode exhaust gas can be used to heat the fuel cell stack. During normal operation when the fuel cell stack is at the desired temperature, the three-way valve in the anode exhaust can be used to bleed nitrogen to the cathode exhaust.

Abstract: A system and method is provided for minimizing the degradation of a fuel cell after shutdown by forcing remaining air out of a fuel cell system. Upon fuel cell shutdown, the flow of air to the cathode of the fuel cell can be kept at a low rate. The flow of cathode exhaust gases along an exhaust conduit is substantially restricted while the pressure of the supply air supplied is increased. As a result, the pressure of the cathode exhaust gases in the exhaust conduit increases. The voltage of the fuel cell can be to deplete the oxygen in the supply air. The pressure of the supply air is decreased to a pressure lower than the pressure of the cathode exhaust gas in the exhaust conduit such that the cathode exhaust gas flows backward through the system to push out any remaining air.

Abstract: A controller (control portion) of a fuel cell system is provided with a flow path switching control device that switches a thermostat valve (flow path switching valve) so that, after a fuel cell has stopped generating electric power, coolant is supplied to a radiator circulation path until the coolant temperature becomes a second temperature threshold value that is lower than a first temperature threshold value.

Abstract: A fuel cell system for use in transportation equipment, for example, can determine an abnormality in its fuel supply device without additional detectors being provided for abnormality detection. The fuel cell system is mounted on a motorbike, and includes a cell stack which includes a plurality of fuel cells, an aqueous solution pump arranged to supply aqueous methanol solution to the cell stack, a controller which includes a CPU, an inflow temperature sensor arranged to detect a temperature of aqueous methanol solution which is introduced to the cell stack, and an outflow temperature sensor arranged to detect a temperature of aqueous methanol solution discharged from the cell stack. The CPU obtains an inflow outflow temperature difference by calculating a difference between a detection result from the inflow temperature sensor and a detection result from the outflow temperature sensor.

Abstract: The present invention provides a method for generating a gas that may be used for startup and shutdown of a fuel cell. In a non-limiting embodiment, the method may include generating a nitrogen-rich stream; merging the nitrogen-rich stream with a hydrocarbon fuel stream into a feed mixture stream; and catalytically converting the feed mixture into a reducing gas.

Abstract: A car battery system includes a plurality of battery cells, each battery cell having a positive electrode terminal and a negative electrode terminal, a battery block that retains the plurality of battery cells in a stacked configuration and has a terminal surface that is formed by battery cell terminal surfaces established by the positive and negative electrode terminals, and a battery state detection circuit that is connected to the electrode terminals of each battery cell to detect the condition of each battery cell. The positive and negative electrode terminals of each battery cell are connected to a circuit board and to the battery state detection circuit. The circuit board is connected to the positive and negative electrode terminals of each battery cell via voltage detection lines, and the voltage detection lines are connected to the same locations on the electrode terminals of each battery cell.

Abstract: A fuel cell system (10) with a toggle switch (32) between an ON or OFF position is provided. In the OFF position, gas is purged from the fuel cell. The fuel cell (12) may surround the fuel source (14) with the cathode side of the fuel cell facing the fuel source. Additionally, both the fuel cell (12) and the fuel source (14) may have similar form factor to maximize the available space. Preferably the form factor is substantially an oval shape. The fuel cell system may also have a pressure regulator (26).

Abstract: A method for filling a fuel cell system with a fuel during start-up is disclosed, the method including the steps of providing a fuel cell stack having a plurality of fuels cells, each fuel cell having an active area, the fuel cell stack including an anode supply manifold and an anode exhaust manifold, the anode supply manifold and in fluid communication with a source of fuel; providing an anode sub-system in fluid communication with an anode side of the fuel cell stack; and supplying the fuel to the fuel cell stack substantially uniformly and substantially simultaneously to compress any fluids in the fuel cell stack into a volume between an end of each active area adjacent to the anode exhaust manifold and an outlet of the anode sub-system.

Abstract: A Flow Cell System that utilizes a Vanadium Chemistry is provided. The flow cell system includes a stack, electrolyte heat exchangers, and a controller executing a state machine.

Abstract: By incorporating a selectively conducting component in electrical series with the anode components in a solid polymer fuel cell, degradation during startup and shutdown can be reduced. As a result, the startup and shutdown procedures can be simplified and consequently certain system apparatus may be omitted. The anode does not need to be rapidly purged with hydrogen on startup or with air on shutdown. Additionally, the auxiliary load usually employed during such purging is not required.

Abstract: A fuel cell system including a fuel cell stack having a plurality of fuel cells, each of the fuel cells including an electrolyte membrane disposed between an anode and a cathode, an anode supply manifold in fluid communication with the anodes of the fuel cells, the anode supply manifold providing fluid communication between a source of hydrogen and the anodes, an anode exhaust manifold in fluid communication with the anodes of the fuel cells, and a fan in fluid communication with the anodes of the fuel cells, wherein the fan controls a flow of fluid through the anodes of the fuel cells after the fuel cell system is shutdown.

Abstract: A fuel cell system may be capable of reducing an adverse influence which acts on a fuel cell at the time of restarting the fuel cell after emergency shutdown of operation of the fuel cell. A fuel cell system includes a fuel cell, a fuel gas supply unit, an oxygen-containing gas supply unit, a storage unit that stores whether shutdown of operation of the fuel cell is normal shutdown or emergency shutdown, and a control unit that controls at least the fuel gas supply unit and the oxygen-containing gas supply unit. The control unit, in emergency shutdown, controls the fuel gas supply unit at a time of restarting the fuel cell after the shutdown of the fuel cell so as to reduce an amount of fuel gas supplied to the fuel cell to be less than that at a time of restarting the fuel cell after normal shutdown.

Abstract: A component for reducing the likelihood of ice-related blockage in a fuel cell and methods for starting a fuel cell system. In one embodiment, the component is a separate insert configured with a sharp leading edge such that water droplets present in a reactant fluid that pass through an orifice in the component are conveyed away from an unstable formation at the edge to a more stable formation in an adjacent part of the component. In one form, the component is sized to fit within a valve inlet that in turn is placed in a humid reactant flowpath. In this way, when the fuel cell is operated in cold conditions—such as those associated with temperatures at or below the freezing point of water—the water droplets do not freeze in the area around the orifice such that ice-related blockage of the flowpath does not occur.

Abstract: A fuel cell system that employs a method for determining the potential that a freeze condition will exist after the system is shut-down based on predetermined input, such as ambient temperature, geographical location, user usage profile, date, weather reports, etc. If the system determines that a freeze condition is probable, then the system initiates a purge shut-down of the fuel cell system where water is purged out of the reactant gas flow channels. If the system determines that a freeze condition is unlikely, then it will initiate a normal shut-down procedure without purging the flow channels. The system will then periodically determine if the conditions have changed, and will initiate the purge if a freeze condition subsequently becomes probable.

Abstract: Disclosed herein is a method of forming an electrolyte membrane comprising forming a mixture; the mixture comprising a polyhydroxy compound, an aromatic polyhalide compound and an alkali metal hydroxide; disposing the mixture on a porous substrate; reacting the mixture to form a crosslinked proton conductor; and sulfonating the proton conductor. Disclosed herein too is an article comprising a porous substrate; and a sulfonated crosslinked proton conductor disposed within pores of the porous substrate.

Abstract: An enclosure houses a fuel cell and defines an enclosed volume around the cell and is provided with openings selectively closed off by mobile shutters for regulate of air circulation between the enclosure interior and exterior, the cell being placed in the enclosure on a support floor, wherein the device comprises at least one selective heating member, separate from the cell, placed in the enclosure underneath the floor, and a volume situated under the floor housing the at least one heating member communicates with the volume of the enclosure situated above the floor via at least one passage.

Abstract: The subject of the present invention relates to a method and a protector for reducing degradation of fuel cell systems at transitions in operation, in particular at electrodes or catalysts in a combustion chamber of a stack of a PEM fuel cell system in startup and shutoff events of the fuel cell system. A switchable material delivery device is provided for varying a delivery of material to the fuel cell system, so that a transition from a first state of the fuel cell system to a second state of the fuel cell system can be initiated, such that a potential difference between different electrodes can be effected. At least one reducing mechanism is provided for reducing the potential difference between the different electrodes during the transition, in which the reducing mechanism includes at least one compensating device for an unequal gas distribution by reducing the proportions causing degradation, to reduce degradation.

Abstract: A fuel cell system (1), especially in a motor vehicle, is provided with a fuel cell (2), which generates electric current during the operation from anode gas and cathode gas, with a residual gas burner (3), which reacts anode waste gas with cathode waste gas into burner waste gas during the operation; with an air delivery device (17), which feeds air as cathode gas to the fuel cell (2) via a fuel cell air line (12) during the operation; and with a first heat exchanger (14), which couples a waste gas line (13) removing burner waste gas from the residual gas burner (3) with the fuel cell air line (12) in a heat-transmitting operation.

Abstract: A hydrogen system (10) comprising a reformer (12), in which a vaporized hydrocarbon fuel (50) is reformed to yield a reformate gas (62) comprising hydrogen, and a hydrogen consumer (40), the reformer and the hydrogen consumer being arranged in fluid communication such that the reformate gas can be fed to the hydrogen consumer, the hydrogen consumer, when in use, consuming at least a part of the hydrogen produced by the reformer wherein the hydrogen system further comprises:—an off gas burner (35) which is arranged such that it is in fluid communication with the hydrogen consumer and a first heat exchanger (21), in which offgas burner, when in use, remaining reformate gas in offgas from the hydrogen consumer is combusted, producing exhaust gas (53) which is passed through the first heat exchanger;—at least one air pump (30) which is arranged such that it is in fluid communication with the reformer and the offgas burner, the at least one air pump, when in use, supplying air to said reformer and offgas burner,—a

Abstract: A fuel cell system includes a fuel cell stack, an oxygen-containing gas supply apparatus, a fuel gas supply apparatus, a pressure reduction apparatus, and a dilution apparatus. The oxygen-containing gas supply apparatus supplies an oxygen-containing gas to the fuel cell stack. The oxygen-containing gas supply apparatus is capable of supplying the air to the fuel gas flow field at the time of stopping operation of the fuel cell system. The fuel gas supply apparatus supplies a fuel gas to the fuel cell stack. The pressure reduction apparatus suctions gases in the oxygen-containing gas flow field and the fuel gas flow field. The dilution apparatus dilutes the fuel gas suctioned by the pressure reduction apparatus using the air.

Abstract: In the present invention, after the initial setting of the FC entry target pressure, the FC entry target pressure is maintained at this initial-setting value until the concentration of impurities in the gas supplied to the anode in the fuel cell falls below a certain value. This initial-setting value is set to a pressure higher than the FC entry target pressure set in response to the FC electric current during normal power generation. If the concentration of impurities in the gas supplied to the anode in the fuel cell has fallen below the certain value, then the FC entry target pressure is sought using a map showing the relationship between the FC electric current detected in step S5 and the entry target pressure set in response to the output required for the fuel cell.

Abstract: A fuel cell system (1), especially in a motor vehicle, includes at least one fuel cell (2) for generating electricity, at least one reformer (3) for generating a reformat gas, a fuel supply means (13) for feeding fuel to the reformer (3), a recycling means (83), which has a recycling line (31) connected to the reformer (3) for feeding anode waste gas of the fuel cell (2) to the reformer (3), and an air supply means (17), which has an air line (18) connected to the reformer (3) separately from the recycling line (31) for feeding air to the reformer (3). To increase performance, the fuel supply means (13) may be designed such that fuel can be introduced with it into the recycling line (31).

Abstract: An exemplary cooling arrangement for high temperature fuel cell system for substantially reducing the amount of purge gas in a system shutdown situation includes a fuel cell having an anode side, a cathode side, and an electrolyte between the anode side and the cathode side. The cooling arrangement includes a coolant source capable of providing coolant to be used in a cooling process of the high temperature fuel cell system during the system shutdown situation, and a cooling structure in connection with the coolant source arranged in a thermal effect area of the fuel cell stacks. The arrangement also includes the vessel that feeds the coolant into the cooling structure from the coolant source, a heat exchanger that exhausts used coolant from the cooling structure, and an actuating device that uses a triggering force to trigger a coolant flow in the cooling structure, when the system shutdown situation has started.

Abstract: A fuel cell system includes a fuel cell that generates electric power using fuel gas and oxygen-containing gas and combusts fuel gas remaining unused for generation of electric power; a fuel gas supply line that supplies the fuel gas to the fuel cell; and an on-off valve disposed in the fuel gas supply line. A shutdown transition mode in which the fuel gas in the fuel gas supply line downstream from the on-off valve is supplied to the fuel cell at a flow rate smaller than that at a time of generation of electric power and is combusted therein after the on-off valve is closed, and a shutdown mode which is started after the shutdown transition mode are provided as an emergency shutdown mode in which the fuel cell undergoes emergency shutdown when the on-off valve of the fuel gas supply line is closed.

Abstract: The fuel cell device has a control device for conducting, at the time of startup, a partial oxidation reforming reaction (POX) inside the reformer, then an auto-thermal reforming reaction (ATR) inside the reformer, then a steam reforming reaction (SR) inside the reformer; a water supply device is provided with a pump for intermittently supplying extremely small amounts of water to the reformer using pulsed control; the control device controls the fuel supply device, the reforming air supply device, and the water supply device to respectively supply target supply flow rates of fuel, reforming air, and water based on the outputs of various sensors; and, in the ATR region, the control device suppresses changes in the flow rate of fuel supplied by the fuel supply device during at least a predetermined interval following the supply of water by the pump.

Abstract: A power generation system of the present invention comprises a fuel cell system (101), a gas supply device, a controller (102), a combustion device (103), an exhaust passage (70), a gas passage used to supply a gas supplied from the gas supply device to the exhaust passage (70), and a back-flow preventing device (20) placed in the gas passage or the exhaust passage (70), and the controller (102) executes an operation for relieving a state in which a valve element remains incapable of moving away from a valve seat in the back-flow preventing device (20) in such a manner that the gas supply device is operated so that a differential pressure between an upstream side and a downstream side of the back-flow preventing device (20) becomes a value equal to or greater than the predetermined time which can relieve the state in which valve element remains incapable of moving away from the valve seat, during a shut-down state or at start-up of the fuel cell system (101).

Abstract: A system for activating a fuel cell includes a flow meter for measuring the amount of water discharged from an outlet of the air electrode and an outlet of the fuel electrode; a pressure sensor for measuring the pressure at the respective outlets; and a back pressure regulator receiving flow values measured by the flow meters and pressure values measured by the pressure sensors, which are fed back from a controller, and regulating a pressure difference (?P=PCathode?PAnode) to be a value greater than 0. With the system, the activation time of a fuel cell and the amount of hydrogen used for the activation can be reduced, thus improving the productivity and manufacturing cost.

Abstract: The fuel cell power plant operating system (10) includes an on/off switching device by-pass circuit (60) to sustain operation of a fuel cell (12) whenever the fuel cell (12) on/off switching device (58) is turned off while a fuel cell operating temperature is below a predetermined freeze-safe operating temperature. The by-pass circuit (60) operates the fuel cell (12) until the fuel cell (12) temperature reaches or exceeds the freeze-safe temperature to thereby prevent fuel cell (12) product water from becoming ice in and adjacent fuel cell catalysts (26, 40).

Abstract: A process for operating a fuel cell system (1), especially in a motor vehicle. The fuel cell system (1) includes at least one fuel cell (3) as well as at least one reformer (2). To improve the possibility of warm start, a warm-holding mode, in which heat transfer takes place from the fuel cell (3) to the reformer (2), is activated after switching off the fuel cell system (1).

Abstract: A fuel cell system includes: an oxidizing gas supply shut valve; an oxidizing gas exhaust shut valve; a cathode pressure measuring unit as a pressure detection unit for detecting a cathode pressure value which is a pressure of a channel between the oxidizing gas supply shut valve and the oxidizing gas exhaust shut valve; a stop processing unit which closes the oxidizing gas supply shut valve and the oxidizing gas exhaust shut valve when operation of the fuel cell stack is stopped; and a judgment unit which judges whether the operations of the oxidizing gas supply shut valve and the oxidizing gas exhaust shut valve have failed according to the cathode pressure value upon stop when the operation of the fuel cell stack is stopped and the cathode pressure value upon start when the operation of the fuel cell stack is started after the stop.

Abstract: A method of activating a fuel cell includes: supplying a fuel to an anode of the fuel cell; supplying a gas mixture to a cathode of the fuel cell; applying a second load, which is equal to or less than a predetermined first load, to a stack of the fuel cell after supplying the gas mixture to the cathode; discontinuing the supply of the gas mixture; resupplying the gas mixture to the cathode when a voltage of the stack of the fuel cell is a predetermined voltage or less after discontinuing the supply of the gas mixture; and applying a third load, which is higher than the predetermined first load, to the stack of the fuel cell, where the supply of the fuel to the anode of the fuel cell is maintained.

Abstract: A method of operating a fuel cell system including stopping power generation of a fuel cell which generates electric power using a fuel gas and an oxidizing gas, filling and keeping a combustible gas in a cathode of the fuel cell after said step, supplying the oxidizing gas to the cathode, supplying the combustible gas discharged from the cathode in response to the previous step to a combustor capable of heating a fuel generator for generating the fuel gas or an exhaust pipe connected to the combustor via a branch passage branching from an oxidizing gas passage located downstream of the cathode, diluting the combustible gas supplied to the combustor or the exhaust pipe with air supplied to the combustor or exhaust gas supplied to the exhaust pipe such that the combustible gas has a concentration lower than a combustion lower limit, and discharging the diluted combustible gas to atmosphere.

Abstract: A system and method for detecting small hydrogen leaks in an anode of a fuel cell system. The method includes determining that a shut-down sequence has begun, and if so, deplete the cathode side of a fuel cell stack of oxygen. The method then increases the pressure of the anode side of the fuel cell stack to a predetermined set-point, and monitors the pressure decay of the anode side of the stack. The method compares the rate of pressure decay to an expected pressure decay rate, and if the measured pressure decay rate exceeds the expected pressure decay rate by a certain threshold, determines that a potential leak exists.

Abstract: An object is to suppress the degradation of durability due to a heat concentration while performing a rapid warm-up operation as necessary, when starting a fuel cell system at temperatures below freezing point.

Abstract: A gas supply device for use in a fuel cell system, comprises: a first injector configured to have a first maximum valve-openable pressure; a second injector arranged in parallel with the first injector and configured to have a lower flow rate than the first injector and a greater second maximum valve-openable pressure than the first maximum valve-openable pressure; a first pressure sensor located upstream of the first and second injectors; and a controller configured to control open/close operation of the first and second injectors, wherein at a start of the fuel cell system, (i) when pressure in the upstream of the first and second injectors is greater than the first maximum valve-openable pressure but is less than or equal to the second maximum valve-openable pressure, the controller opens the second injector, and (ii) when the pressure in the upstream of the first and second injectors is less than or equal to the first maximum valve-openable pressure, the controller opens the first injector or the second i