Abstract: A method for detecting a critical concentration of hydrogen in the exhaust gas of a fuel cell system (1), in which exhaust gas from an anode chamber (4) of a fuel cell (3) is post-combusted by means of a burner (17). The temperature of the combustion exhaust gases is detected, the temperature being compared to a predetermined limit value. In the comparison, a critical concentration of hydrogen is assumed if the temperature of the combustion exhaust gases is above the limit value.

Abstract: A supply assembly and a fuel cell system having a supply assembly that demonstrates a cost-effective and/or resilient design in operation. A supply assembly for coupling to a fuel cell device is proposed, having a gas-to-gas humidifier that is designed and/or arranged in order to humidify the oxidation means A for the fuel cell device by means of the humidity from the exhaust gases B of the fuel cell device has an exhaust gas region and an oxidation means region that are separated from one another by a separation layer. The separation layer enables a transmission of the humidity from the exhaust gas region into the oxidation means region for humidification of the oxidation means A, wherein the gas-to-gas humidifier has a monolithic honeycomb structure for fowling the exhaust gas region and the oxidation means region.

Abstract: The invention relates to a method and a device for operating a fuel cell system (1) having a recirculation blower (11) disposed in a fuel circuit of the fuel cell system (1) by means of which the fuel (BS) exiting the fuel cell system (1) on the anode side is resupplied, said blower being driven by an air-driven drive turbine (12), wherein the air-driven drive turbine (12) is impacted by compressed air (vL).

Abstract: A fuel cell system includes at least one fuel cell and at least one air conveyor that conveys a process air flow to the fuel cell. At least one heat exchanger is also provided, through which the process air flow flows after the air conveyor and through which a cooling medium flow flows. A region with catalytically active material is arranged in the flow direction of the process air flow before or in the region of the heat exchanger. In addition a fuel can be fed to the region with the catalytically active material.

Abstract: A device used to provide hot exhaust gases for driving a turbine. The device includes a burner, the combustion zone of which is directly mounted on or integrated into the gas inlet (turbine housing) of the turbine. The burner is supplied with at least one combustible gas or gas mixture. The combustion zone includes a porous material with a large specific surface area.

Abstract: A fuel cell system includes at least one fuel cell and at least one air conveyor that conveys a process air flow to the fuel cell. At least one heat exchanger is also provided, through which the process air flow flows after the air conveyor and through which a cooling medium flow flows. A region with catalytically active material is arranged in the flow direction of the process air flow before or in the region of the heat exchanger. In addition a fuel can be fed to the region with the catalytically active material.

Abstract: The invention relates to devices for operating fuel cells. According to the invention, the two functions “cooling” and “humidification” are combined in a functional unit (10) to adjust the temperature of the air (1) supplied as the reaction medium and to humidify it. Membranes (5) are used that consist of a temperature-resistant material.

Abstract: A fuel cell system includes a fuel cell with cathode and anode regions. The fuel cell system also includes an exchanging device through which an intake air flow flows to the cathode region and a used air flow is discharged from the cathode region. In the exchanging device, heat is transferred from the intake air flow to the used air flow, and water vapor is simultaneously transferred from the used air flow to the intake air flow. A compressor is arranged downstream of the exchanging device to receive used air. A catalytic material is arranged upstream of the turbine, to which material can be supplied a fuel-containing gas. The catalytic material is integrated into the exchanging device on the used air side and an exhaust gas from the anode region is supplied to the used air side of the exchanging device.

Abstract: A fuel cell system includes a fuel cell with a cathode region and an anode region. The fuel cell system also includes at least one device, which is flown through by an intake air flow flowing to the cathode region and by a used air stream discharged from the cathode region. It also includes catalytic material for the thermal conversion of fuel-containing gas. A first unit with catalytic material is arranged in the flow direction of the intake air flow upstream the at least one device. An exhaust gas from the anode region can be fed to this first unit as a fuel-containing gas. A second unit with catalytic material is arranged in the flow direction of the used air flow downstream of the at least one device.

Abstract: A fuel cell system comprises a fuel cell with a cathode region and anode region. The fuel cell system includes an exchanging device, which is flown through by an intake air flow flowing to the cathode region and by a used air flow discharged from the cathode region. In the exchanging device, heat is transferred from the intake air flow to the used air flow, and water vapor is simultaneously transferred from the used air flow to the intake air flow. At least part of the exchanging device is provided with a catalytic material at the intake air side. Furthermore, an exhaust gas from the anode region is fed to the exchanging device at the intake air side.

Abstract: A supply assembly and a fuel cell system having a supply assembly that demonstrates a cost-effective and/or resilient design in operation. A supply assembly for coupling to a fuel cell device is proposed, having a gas-to-gas humidifier that is designed and/or arranged in order to humidify the oxidation means A for the fuel cell device by means of the humidity from the exhaust gases B of the fuel cell device. The gas-to-gas humidifier has an exhaust gas region and an oxidation means region that are separated from one another by a separation layer. The separation layer enables a transmission of the humidity from the exhaust gas region into the oxidation means region for humidification of the oxidation means A, wherein the gas-to-gas humidifier has a monolithic honeycomb structure for forming the exhaust gas region and the oxidation means region.

Abstract: The invention relates to a method and a device for operating a fuel cell system (1) having a recirculation blower (11) disposed in a fuel circuit of the fuel cell system (1) by means of which the fuel (BS) exiting the fuel cell system (1) on the anode side is resupplied, said blower being driven by an air-driven drive turbine (12), wherein the air-driven drive turbine (12) is impacted by compressed air (vL).

Abstract: The invention relates to devices for operating fuel cells. According to the invention, the two functions “cooling” and “humidification” are combined in a functional unit (11, 12) to adjust the temperature of the air (1) supplied as the reaction medium and to humidify it, wherein the known hollow fiber design for membrane humidifiers having a high specific surface can preferably be used for the charge air cooler (3). These hollow fibers may also consist of a temperature-resistant membrane material (5) and give off water vapor to the inlet gas.

Abstract: The invention relates to devices for operating fuel cells. According to the invention, the two functions “cooling” and “humidification” are combined in a functional unit (10) to adjust the temperature of the air (1) supplied as the reaction medium and to humidify it. Membranes (5) are used that consist of a temperature-resistant material.

Abstract: An apparatus for humidifying a gas stream includes a humidifier device having at least one membrane permeable to water vapor. The gas stream and a humid gas stream flow through a humidifier device, being separated from one another by the at least one membrane. The apparatus includes at least one bypass line configured to route at least part of one of the gas stream and the humid gas stream so that it does not come into contact with the membrane. In addition a method for humidifying a gas stream, includes flowing the gas stream through a humidifier having a membrane permeable to water vapor, flowing a humid gas stream through the humidifier separated by the membrane, and routing at least a portion of one of the gas stream and the humid gas stream using a bypass line so that it does not come into contact with the membrane, and varying a quantity of the portion so as to set a predetermined dew point in the gas stream.

Abstract: A fuel cell includes an electrolyte electrode assembly having a cathode disposed on a first side and an anode disposed on a second side of the electrolyte electrode assembly, a first flow module disposed adjacent the cathode, and a second flow module disposed adjacent the anode. At least one of the first and second flow modules includes a material suitable for exothermal hydride formation. In addition, a method for cold-starting a such fuel cell that includes at least one of the first and second flow modules with a hydrogen-containing gas so as to induce the exothermic hydride formation and release heat; and heating the fuel cell using the heat.

Abstract: A device used for humidifying the flow of a gas which is to be humidified, e.g., fed to a fuel cell system. A moist gas, e.g. a moist waste gas from said fuel cell system is used for said humidification, whereby said gas flows together with the gas flow in a humidifying device. The two gas flows are separated from each other by a membrane in the humidifying device. The membrane is exclusively permeable for water vapour. According to the invention, at least one bypass line is provides. At least one of the gas flows can be partially guided via said bypass line around the region of the membrane in the humidifying device. The saturation point can thus be freely adjusted in an advantageous manner in the gas which is to be humidified.

Abstract: A fuel-cell system, in particular for a vehicle, has a device for supplying the operating agents for a fuel cell and an electrical energy accumulator. The energy accumulator is composed of a battery and of an intermediate charge store which has a lower internal resistance than the battery. A switch is provided in the electrical connection between the energy accumulator and the fuel cell.

Abstract: In a method of operating a fuel cell with fuel circulation, the recirculated moist fuel exhaust stream serves to humidify the fuel inlet stream. The fuel stoichiometry and operating temperatures may be adjusted or selected to control the humidity of the fuel inlet stream.

Abstract: A fastening device for a convertible top according to the invention comprises a front bow; a front window frame; a bracket, which is arranged on one of the group of the front bow and the front window frame; a first catch element, which is assigned to the respectively other component of the group of the front bow and the front window frame, said first catch element being secured in a movable manner and being connectable to said bracket, it being possible for the first catch element to be pivoted about a first axis; and at least one second catch element, which can be connected to said bracket; wherein the second catch element can be pivoted about a second axis, said second axis being spaced apart from said first axis.