Abstract: The invention relates to a method for determining the length and/or volume of a purge path within a fuel cell system (100), the fuel cell system (1) comprising a fuel cell stack (101), an air path (10), an exhaust line (12), and a fuel line (20) with a recirculation loop (50). During the purging process, the H2 concentration is measured on an H2 sensor (45) in the exhaust line (12) and the length and/or volume of the purge path is/are determined as a function of the profile of the measured H2 concentration.

Abstract: A fuel-cell system is proposed, comprising at least one fuel cell, an oxidant line, a hydrogen line, an exhaust-gas line, a control unit, and at least one electrically controllable valve, which is coupled to the control unit and is connected to one from among the oxidant line, the hydrogen line, and the exhaust-gas line. The fuel-cell system is distinguished in that the control unit is designed to activate the at least one valve in a pulsating or oscillating manner, at least during a first time interval, such that the at least one valve is prevented from remaining in a stationary state and seizing up by icing during the first time interval.

Abstract: A method for operating a drive unit operated with gaseous fuel. The gaseous fuel is provided under high pressure in a plurality of pressure tanks that can be connected via a supply line and with a metering valve via which the gaseous fuel can be dispensed to the drive unit. One of the pressure tanks is designed as a high-load pressure tank which is only connected to the supply line when the drive unit is under high load, the pressure tanks in which a lower gas pressure prevails than in the high-load pressure tank simultaneously being disconnected from the supply line.

Abstract: The invention relates to a method for keeping free of ice or thawing at least one surface (1) which is at risk of icing of a tank interface (2), wherein the at least one surface (1) at risk of icing is formed on a refueling nozzle (3) and/or on a tank filler neck (4) of a vehicle which can be operated with hydrogen. According to the invention, the at least one surface (1) at risk of icing is heated during a refueling operation and/or after a refueling operation. The invention further relates to a tank interface (2) and to a vehicle, which can be operated with hydrogen, having a tank interface (2) according to the invention.

Abstract: The invention relates to a fuel cell (1) for a fuel cell stack (11), comprising a polymer membrane (2) which serves as an electrolyte and has respectively on both sides a catalyst layer (3, 4) for forming an anode (3) on the one side and a cathode (4) on the other side, a gas diffusion layer (5) and a bipolar plate (6) being applied to each of the two analyst layers (3, 4). According to the invention, a short-circuit element (7) is applied, preferably printed, to at least one bipolar plate (6), namely on the side facing away from the gas diffusion layer (5). The invention also relates to a fuel cell stack (11) and to a method for operating a fuel cell stack (11).

Abstract: The invention relates to a heat exchanger system for operating a fuel cell stack, comprising: a first compressor and a second compressor for the cathode gas fed to the fuel cell stack, the second compressor being fluidically downstream of the first compressor; a turbine, which is mechanically coupled to the second compressor and against which the cathode gas discharged from the fuel cell stack flows; a first heat exchanger, which is thermally coupled to the fed cathode gas between the first compressor and the second compressor; a second heat exchanger, which is thermally coupled to the fed cathode gas downstream of the second compressor; a fourth heat exchanger, which is thermally coupled to the discharged cathode gas downstream of the turbine; wherein the fourth heat exchanger is thermally variably coupled to the first heat exchanger and to the second heat exchanger in order to control a heat exchange for cooling the first heat exchanger and the second heat exchanger.

Abstract: The invention relates to a pressurized gas tank receiving assembly (1) for a motor vehicle (100) for cooling pressurized gas tanks (10), wherein the pressurized gas tank receiving assembly (1) comprises: a) a main body (20) with a plurality of supporting surfaces (22) in the form of channels for receiving the pressurized gas tank (10), wherein the main body (20) is thermally conductive and has a mounting interface (26) for arrangement on a counter mounting interface (126) of a body (120) of the motor vehicle (100), wherein the main body (20) has thermally conducting surfaces (24) for thermally communicating connection to the body (120), b) pressurized gas tanks (10) for storing gas under high pressure, wherein the pressurized gas tanks (10) are thermally conductive and are interlockingly received on the supporting surfaces (22) of the main body (20), which supporting surfaces are in the form of channels, for thermal communication with the main body (20).

Abstract: The invention relates to a method for opening a valve assembly for a fuel tank, comprising a pilot valve (V1) and at least one additional valve (V2), in particular for use in a fuel cell-operated vehicle, having the steps of applying (30) an amplification voltage (S1) in order to open the pilot valve (V1) in an opening phase (P1) of the pilot valve (V1), deactivating (32) the amplification voltage (S1) in order to terminate the opening phase (P1) of the pilot valve (V1), applying (34) a pull-in voltage (S2) in a pull-in phase (P2) of the pilot valve (V1) in order to hold the pilot valve (V1) open, and activating and deactivating (36) the pull-in voltage (S2) in an alternating manner in order to hold the pilot valve (V1) open and in order to open the at least one other value (V2) and hold same open in a readjustment phase (P3) such that the hold-open energy required on average for holding the pilot valve (v1) open and the opening energy and/or hold-open energy required on average for the at least one other val

Abstract: The invention relates to a method for filling a hydrogen tank (2) of a motor vehicle (1) comprising a fuel cell drive, wherein the method comprises the steps: (a) determining a first operating time at which the motor vehicle (1) is to be started up and an expected first operating location at which the motor vehicle (1) is to be started up, (b) ascertaining a predicted maximum ambient temperature (TU,max) at the first operating location at the first operating time, and (c) filling the hydrogen tank with hydrogen (3) until a tank pressure (p) in the hydrogen tank (2) reaches a maximum permissible tank pressure (pmax) at a tank temperature (T), wherein the following applies for the tank temperature (T): tank temperature (T)=[maximum ambient temperature (TU,max); maximum ambient temperature (TU,max)+10 K].

Abstract: The invention relates to a fuel cell (1) for a fuel cell stack (11), comprising a polymer membrane (2) which serves as an electrolyte and has respectively on both sides a catalyst layer (3, 4) for forming an anode (3) on the one side and a cathode (4) on the other side, a gas diffusion layer (5) and a bipolar plate (6) being applied to each of the two analyst layers (3, 4). According to the invention, a short-circuit element (7) is applied, preferably printed, to at least one bipolar plate (6). namely on the side facing away from the gas diffusion layer (5). The invention also relates to a fuel cell stack (11) and to a inetliod for operating a fuel cell stack (11).

Abstract: The invention relates to a method for refuelling a vehicle (60) or an autonomous vehicle (60). At least one hydrogen tank (10) accommodating gaseous hydrogen is fitted in the vehicle (60). The method comprises the following method steps: The vehicle (60) drives into a refuelling area (24). A refuelling operation (28; 78, 80, 82) is performed on the vehicle (60). Then, the temperature of the contents of the at least hydrogen tank (10) is checked (30). If a temperature (74) of the tank contents of the at least one hydrogen tank (10) exceeds a temperature limit value (32), the vehicle (60) is transferred to a cooling down area (36). There, the tank temperature (44) is checked a second time following a cooling down phase. The tank pressure is checked (48) if the tank temperature (74) lies below a temperature limit value.

Abstract: The invention relates to a method for operating a fuel cell system, in particular a PEM fuel cell system, in which an QI anode gas is supplied to an anode (1) of a fuel cell via a supply path (2), and is fed back via a recirculation path (3) connected to the anode (1), wherein hydrogen is used as the anode gas. According to the invention, during the start up of the fuel cell system, the anode gas is supplied to a drying device (4), in particular an adsorber, via at least one normally open valve (8, 9, 10), and water is extracted from the anode gas using the drying device (4). The invention also relates to a fuel cell system, in particular a PEM fuel cell system, which is suitable for carrying out the method.

Abstract: The invention relates to a method for detecting a leak in an energy converter system (1) containing a gas. A pressure regulator (3) is used to regulate a gas pressure in the energy converter system (1), and the pressure regulator (3) has a gas metering valve (4). The method has the following steps: a. measuring an inlet pressure (10) of the pressure regulator (3) and measuring an outlet pressure (12) of the pressure regulator (3), b. measuring an output variable (16) of the energy converter system (1) and calculating a gas requirement in the energy converter system (1) on the basis of the output variable (16) of the energy converter system (1), c. determining a first calculated flow (20) through the pressure regulator (3) on the basis of the measured inlet pressure (10) of the pressure regulator (3) and the measured outlet pressure (12) of the pressure regulator (3), d. determining a second calculated flow (22) through the pressure regulator (3) on the basis of the gas requirement, e.

Abstract: The invention relates to a turbo compressor (10), in particular for a fuel cell system (1). The turbo compressor (10) has a first compressor unit (101) and a second compressor unit (102). The first compressor unit (101) comprises a first compressor (11) arranged on a first shaft (14) drivable by a drive unit (20). The second compressor unit (102) comprises a second compressor (12) and an exhaust gas turbine (13). The second compressor (12) and the exhaust gas turbine (13) are arranged on a second shaft (24).

Abstract: The invention relates to a distribution structure (10) for providing at least one reaction gas, in particular a gas mixture containing oxygen (O2), for a fuel cell (100) or an electrolyser, having a first structure element (11) and a second structure element (12), wherein the first structure element (11) and the second structure element (12) are designed and arranged with respect to one another such that: a distribution area (15) for the reaction gas is formed between the first structure element (11) and the second structure element (12); a plurality of feed channels (16) branch off from the distribution area (15) and are orientated substantially perpendicular to the distribution area (15); and a plurality of discharge channels (17) are formed below the second structure element (12) and are orientated parallel to the distribution area (15).

Abstract: The invention relates to a method (1) for leakage monitoring of a fuel cell system (200). According to the invention, it is provided that the leakage monitoring is carried out before or during shut-down of the fuel cell system (200) and during or after restarting of the fuel cell system (200).

Abstract: The invention relates to a turbo compressor (10), in particular for a fuel cell system (1). The turbo compressor (10) has a first compressor unit (101) and a second compressor unit (102). The first compressor unit (101) comprises a first compressor (11) arranged on a first shaft (14) drivable by a drive unit (20). The second compressor unit (102) comprises a second compressor (12) and an exhaust gas turbine (13). The second compressor (12) and the exhaust gas turbine (13) are arranged on a second shaft (24).

Abstract: A method for identifying a leak (4?) within a membrane (4) of a fuel cell (5) during operation of a motor vehicle, comprising the steps: reducing the power provided by the fuel cell (5) starting from an output power to a minimum value; determining measurement values of the current cell voltage of the fuel cell (5) whilst the reduced power at the minimum value is provided by the fuel cell (5); and assessing a state of the membrane (4) of the fuel cell (5) on the basis of the determined measurement values in order to identify a leak (4?). The power reduced by the fuel cell (5) whilst measurement values of the current cell voltage are determined is provided at the same level by at least one further energy source.

Abstract: The invention relates to a method for operating a tank system (10) comprising a number of at least two tanks (21, 22, 23, 24, 25), which are connected in parallel and which contain a gaseous substance, and in which an interior pressure (PX) prevails, for supplying a consumer unit (12), which requires a full load volume of the gaseous substance, wherein each tank (21, 22, 23, 24, 25) has a safety valve (31, 32, 33, 34, 35), which shuts down the tank if a flow volume of the gaseous material through the safety valve (31, 32, 33, 34, 35) exceeds a shut-off volume. If the interior pressure (PX) in at least one tank (21, 22, 23, 24, 25) falls below a first threshold, at least one other tank (21, 22, 23, 24, 25) that was previously shut down is connected.

Abstract: The invention relates to a fuel cell system (100, 1) comprising: at least one fuel cell (200) which has a cathode (230) with a cathode chamber and has an anode chamber of an anode (210), which anode chamber is separated from the cathode chamber by a membrane, wherein the cathode chamber is connected to a cathode gas source via at least one first fluid connection (240) and the anode chamber is connected to an anode gas source via at least one second fluid connection; and comprising a first electrical connection (3) to a DC/DC converter (450) that electrically connects the anode (210) and the cathode (230) to an energy system (400), wherein in a shut-down phase of the fuel cell system (100, 1), residual energy present in the fuel cell (200) can be discharged.