Abstract: In a method for operating a fuel cell system having recirculation blower arranged in a fuel cell circuit, fuel discharged from the anode exhaust is fed back to the inlet side of the fuel cell system via the recirculation blower. The direction of flow in the fuel return line is reversed in at least a portion of the return line, in an alternating manner.

Abstract: The present invention provides a hydrogen exhaust system for a fuel cell vehicle, which is configured to actively control an exhaust path of hydrogen discharged from an anode of a fuel cell stack to maximize the safety of the vehicle by minimizing the possibility of explosion due to hydrogen exhaust and ensure the silence of the vehicle by minimizing noise generated during hydrogen exhaust. Moreover, the present invention provides a hydrogen exhaust system for a fuel cell vehicle, which can improve the performance and power of the fuel cell stack by supplying water discharged from the fuel cell stack to an air supply line of the fuel cell stack together with purge hydrogen discharged to a hydrogen exhaust line to increase the humidification performance of the fuel cell stack.

Abstract: A membrane humidifier assembly includes a first flow field plate adapted to facilitate flow of a first gas thereto and a second flow field plate adapted to facilitate flow of a second gas thereto. A polymeric membrane is disposed between the first and second flow fields. The polymeric membrane is adapted to permit transfer of water between the first flow field plate and the second flow field plate. The polymeric membrane includes a polymeric substrate and a polymer layer disposed on the polymeric substrate. The polymer layer characteristically includes a first polymer having fluorinated cyclobutyl groups disposed on the polymeric substrate.

Abstract: A fuel cell vehicle includes: a fuel cell stack for generating electric power by receiving supply of a reaction gas; a humidifying device for delivering an oxidizing off-gas discharged from the fuel cell stack and an oxidizing gas with a water vapor permeable membrane interposed therebetween, and thereby carrying out a moisture exchange between the oxidizing off-gas and the oxidizing gas; and a discharge flow passage for discharging the oxidizing off-gas discharged from the humidifying device to an outside of the vehicle. An oxidizing off-gas outlet that opens toward a front side of the vehicle is formed in the humidifying device. The discharge flow passage is connected to the oxidizing off-gas outlet and is bent in an approximate U shape from a front side of the vehicle to a back side of the vehicle.

Abstract: A fuel cell supply system 6 is proposed for feeding an oxidizing agent to a fuel cell assembly 2, has a continuous flow machine for accelerating and/or increasing the pressure of the oxidizing agent, and a humidifier for humidifying the oxidizing agent. The humidifier is connected or connectable flow-wise between the continuous flow machine and the fuel cell assembly, and has a dehumidifier, which is designed and/or arranged to dehumidify the oxidizing agent.

Abstract: Disclosed is a fuel cell system comprising a reformer and a fuel cell body to which a fuel gas reformed through the reformer and air are supplied and in which the supplied fuel gas and air are separated from each other and caused to flow and contact on respective electrodes to perform electric power generation. A moisture quantity adjustment device is configured to adjustably separate a portion of moisture included in the fuel gas supplied from the reformer in order for the moisture included in the fuel gas to be supplied to the fuel cell body in an appropriate quantity.

Abstract: The present invention provides a method for removing residual water in a fuel cell, which controls the humidity of purge gases to effectively remove residual water in the fuel cell and to maintain the humidity in a membrane at a constant level, thus ensuring the durability of the membrane. For this purpose, the present invention provides a method for removing residual water in a fuel cell, characterized in that the relative humidities of purge gases supplied to an anode and a cathode are controlled to selectively reduce water content in the fuel cell and water content in a membrane.

Abstract: A membrane humidifier for a fuel cell with a wet side plate having a plurality of flow channels formed therein and a dry side plate having a plurality of flow channels formed therein, the flow channels of the wet side plate adapted to facilitate a flow of a wet gas therethrough and the flow channels of said dry side plate adapted to facilitate a flow of a dry gas therethrough, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.

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

Abstract: A cell module includes a cell module body having a tube-shape. The cell module body includes a tube-shaped inner electrode and a tube-shaped outer electrode. The inner electrode is within the outer electrode. The inner electrode forms a hollow portion. The cell module also includes a water permeable hollow body arranged within the hollow portion.

Abstract: According to one embodiment of the present invention, a fuel cell life counter is configured to determine membrane degradation using fuel cell cycling data and S-N curve data for the membrane. According to another embodiment of the present invention, a method of managing remaining fuel cell life is provided where variables like membrane dehydration rate, water content, temperature, and heating/cooling rate are controlled as a function of the remaining life of the fuel cell. Additional embodiments are provided where fuel cell life counters and methods of managing remaining life are independent of S-N curve data and the use of fatigue life contour plots.

Abstract: A solid oxide regenerative fuel cell includes a ceramic electrolyte, a first electrode which is adapted to be positively biased when the fuel cell operates in a fuel cell mode and in an electrolysis mode, and a second electrode which is adapted to be negatively biased when the fuel cell operates in the fuel cell mode and in the electrolysis mode. The second electrode comprises less than 1 mg/cm2 of noble metal.

Abstract: A warm-up apparatus GS for a fuel cell 1, 51 comprising: a compressor 22, 71 for feeding supply gas A to the fuel cell 1, 51; a main passage W1, W3 connecting the compressor 22, 71 and the fuel cell 1, 51 and feeding supply gas A; an intercooler 23, 73 arranged in the main passage W1, W3; and a bypass passage W2, W4 connecting the compressor 22, 71 and the fuel cell 1, 51 and feeding supply gas A in such a manner that the supply gas A bypasses the intercooler 23, 73.

Abstract: A fuel cell system may have at least one sensor including a pair of electrodes disposed on a substrate. The sensor may be configured to produce an output signal having a magnitude that is proportional to a relative humidity in a vicinity of the sensor and, if liquid water is on the sensor, proportional to an amount of the liquid water on the sensor.

Abstract: An electrochemical cell having two or more diffusion bonded layers, which demonstrates a high degree of ruggedness, reliability, efficiency and attitude insensitiveness, is provided. The novel cell structure simplifies construction and operation of these cells. Also provided is a method for passive water removal from these cells. The inventive cell, as well as stacks made using these cells, is suitable for use in applications such as commercial space power systems, long endurance aircraft, undersea power systems, remote backup power systems, and regenerative fuel cells.

Abstract: A fuel cell hydration system comprising a first reservoir is provided. The first reservoir is positioned between a cathode supply and a fuel cell stack. The first reservoir includes corrugated regions positioned axially along the first reservoir to accumulate water discharged from a first fluid stream. The first fluid stream absorbs the accumulated water when an amount of water within the first fluid stream is below a water level to hydrate the fuel cell stack.

Abstract: A fuel source for a hydrogen generator is described. The fuel source includes a chemical hydride, at least one catalyst precursor and a hygroscopic salt. When one or more of the at least one catalyst precursor and hygroscopic salt contact water, a catalyst is formed for facilitating the generation of hydrogen from the chemical hydride.

Abstract: A membrane humidifier for a fuel cell is disclosed, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.

Abstract: A fuel cell stack (32) includes a plurality of fuel cells in which each fuel cell is formed between a pair of conductive, porous, substantially hydrophilic plates (17) having oxidant reactant gas flow field channels (12-15) on a first surface and fuel reactant gas flow field channels (19, 19a) on a second surface opposite to the first surface, each ˜f the plates being separated from a plate adjacent thereto by a unitized electrode assembly (20) including a cathode electrode (22), having a gas diffusion layer (GDL) an anode electrode (23) having a GDL with catalyst between each GDL and a membrane (21) disposed therebetween. Above the stack is a condenser (33} having tubes (34) that receive coolant air (39, 40} to condense water vapor out of oxidant exhaust in a chamber (43). Inter-cell wicking strips (26) receive condensate and conduct it along the length of the stack to all cells.

Abstract: A system and method for humidifying a fuel cell stack system is provided. The system includes a slave stack, a master stack and at least one valve. The slave stack generates power to drive a load in response to at least one fluid stream and discharges at least one recirculated fluid stream having water content therein. The master stack receives the at least recirculated fluid stream to humidify the master stack with the water content. The valve delivers the at least one recirculated fluid stream from the slave stack to the master stack based on a power request amount by the load.

Abstract: The present invention provides a humidification system for a fuel cell, in which a plurality of membrane humidifiers employing hollow fiber membranes of different kinds having different diameters and pore sizes, or having different numbers of hollow fiber membranes is selectively used according to the amount of current generated from a fuel cell stack or a vehicle output, thus adjusting the humidification amount for dry air to be supplied to a fuel cell stack, and preventing the flooding phenomenon caused at a cathode and the starvation phenomenon in which the air supply is insufficient at the cathode.

Abstract: The fuel cell according to the present invention includes a membrane electrode assembly, two diffusion layers, an oxygen supplying layer, a water-absorbing layer, and a current collector. An end portion of the water-absorbing layer is located on a plane including an opening portion or on the fuel cell-side with respect to the plane. A length from one end portion to the other end portion of a part of the oxygen supplying layer which contacts the water-absorbing layer in a cross section of the fuel cell taken along a surface which includes the water-absorbing layer and which is perpendicular to the plane is shorter than a length from one end portion to the other end portion of the water-absorbing layer including a part of the water-absorbing layer which contacts the oxygen supplying layer in the cross section.

Abstract: There is disclosed a fuel cell system capable of drying a fuel cell in a short time after a system stop instruction is issued. The fuel cell system includes a controller to control the execution of a normal operation and a dry operation which decreases the water content of the fuel cell as compared with the normal operation. The controller executes the dry operation prior to the system stop instruction so that the water content of the fuel cell is decreased as compared with the normal operation at a time of the system stop instruction. The controller may execute the dry operation before the system stop instruction in a case where it is predicted that the temperature of the fuel cell at the system stop or the next system start is a predetermined low temperature.

Abstract: A strategy of controlling a state of hydration of a fuel cell(s) and actively managing operation of the fuel cell(s) to achieve a desired state of hydration. The control strategy monitors the state of hydration and a rate of change of the state of hydration which are used to control the operation of the fuel cell(s). A supervisory control strategy is implemented that alters the operating parameters of the fuel cell(s) based upon the state of hydration, the rate of change of the state of hydration, and a desired operational range for the state of hydration.

Abstract: A fuel cell is operated with high power such that which a humidified gas and a dry gas are selectively supplied as oxidant to a cathode of the fuel cell. This method includes (S1) supplying a humidified gas while a power is constantly maintained or until the power begins to decrease; (S2) after supplying the humidified gas, supplying a dry gas to obtain a greater power than an average power of the step (S1); and (S3) after obtaining a predetermined power in the step (S2), repeatedly supplying a humidified gas in case the power decreases and supplying a dry gas in case the power decreases again afterwards, thereby increasing the power such that the predetermined power is maintained. This method provides an optimal operating condition to a fuel cell, thereby ensuring a high power.

Abstract: The present invention provides a humidification system with membranes of different species, in which a material having a high humidification performance and capable of being swollen with water is arranged in the center of a hollow fiber membrane bundle disposed in a hollow fiber membrane module and a material that is not swollen with water is disposed on the outside thereof. Accordingly, using the humidification system of the invention, it is possible to provide the same level of humidification performance as the existing humidification system, manufacture the humidification system at low cost, and solve various problems such as a flooding phenomenon of a fuel cell stack and an increase in load on an air blower.

Abstract: A humidification cell of a fuel cell apparatus includes a first outer plate and a second outer plate. A gas chamber, a humidification chamber and a water-permeable membrane separating the two chambers, are disposed between the first outer plate and the second outer plate, starting from the first outer plate. A first water-permeable support element that prevents fibers from detaching and also prevents medium flows from blocking narrow gas outlets, is disposed between the first outer plate and the membrane in such a way that the first support element is made of a filter material.

Abstract: A polymer electrolyte fuel cell system of the present invention comprises cells 10, a stack 100, a temperature control device (160, 140, 40, 41), an anode gas supplier 110, a cathode gas supplier 120, and a controller 300. When a power generation output of the stack 100 is reduced, the controller 300 controls the anode gas supplier 110 and the cathode gas supplier 120 to reduce a supply amount of the anode gas and a supply amount of the cathode gas, and controls at least one of the anode gas supplier 110, the cathode gas supplier 120, and the temperature control device 100 to cause a dew point temperature of a gas supplied to at least one of the anode gas channels and the cathode gas channels to be higher relative the temperature of the stack 100 so that the gas becomes supersaturated or more supersaturated than prior to causing the dew point temperature of the gas to be higher.

Abstract: A technique that is usable with a fuel cell includes generating a humidified reactant flow. The technique includes measuring a rate of condensate production from the reactant flow and controlling the generation of the humidified reactant flow in response to the measured rate of condensate production.

Abstract: A fuel cell system that employs a technique for safely removing hydrogen gas that accumulates within a cooling fluid reservoir. The fuel cell system includes a fuel cell stack and a compressor for providing airflow to the cathode side of the fuel cell stack. The system also includes an air filter box having an air filter that is in fluid communication with an air pocket in the reservoir. The air intake to the compressor flows through the air filter box, and sucks the gas from the reservoir, which is then sent to the cathode side of the fuel cell stack to be converted to water by the electro-chemical reaction therein.

Abstract: A fuel cell system (100) and operational methods (200, 300 and 400) are described that utilize a combination of sensor input and component models for causing the system's cathode effluent (150) to selectively bypass cathode effluent processing components (140) so as to obtain or maintain a desired cathode inlet relative humidity or dew point. The described system and methods may operate open loop (e.g., without sensor feedback to verify operation) or closed loop (e.g., relying on cathode inlet relative humidity/dew point sensors or fuel cell stack membrane conductivity measures).

Abstract: The present invention provides a method for controlling the amount of air supplied to a fuel cell, which can prevent flooding and membrane dry-out in a fuel cell stack and, at the same time, ensure optimal performance of the fuel cell stack and a humidifier by supplying an optimal amount of air to the fuel cell stack at each operation condition. For this purpose, the present invention provides a method for controlling the amount of air supplied to a fuel cell, the method including measuring the temperature and pressure of humidifier outlet (stack inlet) air, the temperature and pressure of stack outlet air, and the relative humidity of the humidifier outlet (stack inlet) air, and determining the stoichiometric ratio of air or the amount of air supplied to the stack based on the measurement results so as to adjust the relative humidity of the stack outlet air reach a target value.

Abstract: A fuel cell assembly for using hydrogen gas and oxygen to produce electrical energy. The cathode of the fuel cell produces water vapor to define a flow of moist air including water vapor. A dehumidifier receives the flow of moist air including water vapor to produce purified liquid water and a flow of dehumidified air. The dehumidifier has an air inlet having a first cross-sectional area and an air outlet having a larger second cross-sectional area. The diffuser cavity of the dehumidifier progressively increases in size from the air inlet to the air outlet for depressurizing and cooling the flow of moist air including water vapor below the dew point of the moist air including water vapor to condense the water vapor on the housing of the dehumidifier.

Abstract: A humidifier of the present invention includes a humidifier main body for humidifying a second fluid, using a humidified first fluid discharged from a fuel cell; a head portion of which one end is connected to an end of the humidifier main body and the other end is connected to the fuel cell or a supply passage extending from the fuel cell, and which supplies the second fluid after humidification to the fuel cell; and a chamber for communicating a bottom portion of a humidified gas flow passage formed within the head portion.

Abstract: A condenser condenses an unused exhaust gas exhausted from a fuel cell and recovers water, condensation-capacity detection means always monitors the condensation capacity of the condenser, control means controls an output of heat-transport-medium circulation means, stores the exhaust heat of the fuel cell in heat-using means when a sufficient condensation capacity is left, and stops the heat-transport-medium circulation means to complete exhaust-heat recovery when the condensation capacity lowers. Moreover, a fuel cell, a cooling pipe through which a first heating medium of carrying the heat of the fuel cell circulates, a cooling-water pump of circulating the first heating medium, and a fuel-cell-temperature detector of detecting the temperature of the fuel cell are used to operate a cooling-water pump until the temperature detected by the fuel-cell-temperature detector becomes a predetermine threshold value or less even after supply of a fuel and an oxidant to the fuel cell is stopped.

Abstract: Water disposal systems, apparatuses and methods that employ same, and methods for disposing water produced during power generation are provided. A separator of a fuel cell has an air supply groove formed therein for supplying air as an oxidizer gas to a cathode. The separator is also provided with water-absorbing cloths on the midway portion of the air supply groove. More specifically, the water-absorbing cloth is provided on the separator (110), as a water absorbing member for absorbing the water, so as to cover at least a part of the surface on which the air supply grooves is formed and the water-absorbing clothes is provided along the sidewall of the air supply grooves. Water generated during power generation by the power generator of the present invention is disposed in efficient and reliable manners, under a simple configuration.

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

Abstract: A method and apparatus for thermal control of air flow in a fuel cell system, capable of accurately controlling the temperature of the air stream entering the water vapor transfer unit, maintaining a desired temperature set-point, and minimizing the time required for the air stream to reach the optimum operating temperature.

Abstract: There is provided a fuel cell in which produced water can be efficiently conveyed to an upstream region of hydrogen gas flow, thereby quickly increasing the power generation performance of an electrolyte membrane after activation in a short period of time and giving a stable output for a long period of time and in which the directions of hydrogen gas flows in a first and a second fuel supply layers that share one oxygen supply layer are set to be opposite to each other.

Abstract: In a fuel cell system a specific connection and a valve arrangement make it possible for a compressor to supply precompressed air to a fuel cell stack via a waste gas line, said air then leaving the fuel cell stack via a line which is otherwise an air feed line. In this way, a humidifier may be bypassed. This is sensible in particular during a start phase at low ambient temperatures, during which the fuel cell system is intended to warm up without moisture in the fuel cell stack having a negative effect, for instance by freezing. The compressor may be operated both in the start phase or stop phase and during conventional operation by the same mode of operation.

Abstract: A fuel cell includes a membrane electrode assembly includes a fuel electrode, an air electrode and an electrolyte membrane interposed between the fuel electrode and the air electrode, a fuel supply mechanism disposed on the air electrode side of the membrane electrode assembly to supply fuel to the fuel electrode, and a humidification layer disposed on the air electrode side of the membrane electrode assembly to be impregnated with water produced in the air electrode. The humidification layer include a first humidification section disposed opposite to a high-temperature area of an air electrode and a second humidification section disposed opposite to a low-temperature area of the air electrode when generating electricity. The second humidification section is so configured that water vapor is released into air therefrom more easily than from the first humidification section in the membrane electrode assembly.

Abstract: A method of operating fuel cell system includes generating electricity by a fuel cell using fuel gas and oxidizing gas and allowing cooling water to flow in the fuel cell and thereby cooling the fuel cell. The method includes transferring moisture from exhaust gas to supply gas using a first humidifier, the exhaust gas being discharged from the fuel cell, the supply gas being supplied to the fuel cell, and transferring moisture from the cooling water to the supply gas humidified using a second humidifier. The method includes at least one of detecting humidity of the supply gas humidified, detecting temperature of the cooking water, detecting the flow rate of the supply gas and detecting the amount of electricity generated by the fuel cell. The method also includes controlling the humidity of the supply gas humidified based on the value detected.

Abstract: A particle size distribution creating method includes a particle size range determining step, an integrating step of integrating the frequency of appearance of particles within the particle size range determined in the particle size range determining step, a division point determining step of determining particle sizes that provide division points, using the integral of the frequency of appearance obtained in the integrating step, and a typical point determining step of determining the minimum particle size, maximum particle size and the particle sizes of the division points as typical points.

Abstract: A fuel cell system of the present invention includes: a fuel cell (10) having a fuel gas internal channel (11) and an oxidizing gas internal channel (12); oxidizing gas supplying passages (62) and (64); an oxidizing gas supplying device (31); oxidizing gas discharging passages (65) and (66) each having an upstream end communicated with the oxidizing gas internal channel (12) and a downstream end connected to the oxidizing gas supplying passage (64); a moisture exchanger (32) disposed on both the oxidizing gas supplying passage (62) and the oxidizing gas discharging passage (65); a gas circulating passage forming/canceling device (34) disposed on the oxidizing gas discharging passage (66); an air blower (35) configured to circulate a gas in a gas circulating passage; and an atmosphere communicating/closing device (33) disposed on the oxidizing gas supplying passage (62).

Abstract: A PEMFC is operated in an operation mode in which a membrane-based humidifier is used to transfer moisture from a moisture-laden exhaust stream to the dry air feed and in a shutdown mode in which the membrane-based humidifier is used to permeate moisture and oxygen from the moisture-laden exhaust stream to provide a N2-rich exhaust for purging of the anode.

Abstract: A fuel cell system and a method for driving the fuel cell system are disclosed. In one aspect, the fuel cell system may include a fuel stack, a fuel supply unit, an oxidizer supply unit, a humidifying unit, and a controller configured to measure the temperature of unit cells within the fuel cell stack and configured to detect the lowest measured temperature. The fuel cell stack may include a membrane electrode assembly and a plurality of unit cells. The membrane electrode assembly may include a membrane, a cathode disposed at a first side of the membrane and an anode disposed at a second side of the membrane.

Abstract: The invention detects quickly and with high precision abnormalities in fuel cells. In a method of detecting abnormalities in a fuel cell 1 comprising a plurality of unit cells that generate power by supplying hydrogen gas to an anode and supplying air to a cathode of each unit cell, the abnormality in the fuel cell 1 is detected based on the speed of the decrease in the cell voltages after stopping the fuel cell, i.e., after stopping the supply of the reacting gases to the fuel cell.

Abstract: The invention relates to a separator plate for use in a fuel cell and to a fuel cell. The separator plate has: a passage groove group including a plurality of gas passage grooves 35 formed so as to extend in serpentine form; and a communicating groove 33 configured to provide fluid communication between adjacent portions of the gas passage grooves. Various separator plates have heretofore been disclosed in public by many documents and the blockage of the gas passage grooves caused by condensed water droplets formed therein is deemed to be properly prevented. However, the inventors think that those separator plates have a critical oversight in the behavior of a gas-liquid two phase fluid including a reaction gas and condensed water. That is, the condensed water is likely to concentrate in the vicinity of the gas passage grooves located in the downstream side of such separator plates and therefore these separator plates are liable to blockage.

Abstract: According to one embodiment, a fuel cell apparatus includes a cell stack of an active direct methanol type, and a DC-DC converter configure to receive output voltage of the cell stack and to control an output current of the cell stack so that the output voltage of the cell stack becomes greater than a lower-limit threshold Vt and the output current of the cell stack lies in a range of I1 to I2 (<I1).

Abstract: The present invention discloses methods and devices for humidifying the proton exchange membranes of fuel cells with water obtained from the exhaust of the fuel cells. Humidifying methods include the following steps: cooling the hot and humid exhaust of the fuel cell to condense the water in the exhaust with the intake gas for the fuel cell; separating the water from the rest of the exhaust, and, delivering the water to the intake gas of the fuel cell. Humidifying devices include an outer shell containing a rotating inner shell. The inside of the inner shell forms a chamber where the exhaust is collected and cooled, and water is condensed and separated by the rotation of the inner shell. Openings on the inner shell allow the condensed water to pass through to one or more chambers containing the intake gas. The chambers are formed by the inside of the outer shell and the outside of the inner shell.