Abstract: The invention relates to a device for electrically connecting at least one fuel cell stack and at least one high-voltage battery for supplying electrical energy to consumers which are connected on the side of the high-voltage-battery. The invention is characterized in that the fuel cell stack and the high-voltage battery are connected to one another via at least one diode, which blocks current flow in the direction of the fuel cell stack, and at least one switch for closing and breaking the connection. According to the method, the switch is controlled depending on the voltages of firstly the at least one fuel cell stack and secondly the at least one high-voltage battery.

Abstract: The invention relates to a fuel cell facility (1) having two parallel fuel cell systems (13, 14), each of which comprises at least one fuel cell stack (15, 16, 17, 18) having anode-side and cathode-side periphery, and having a common air conveying device (2), The fuel cell facility (1) according to the invention is characterized in that the air conveying device (2) is designed in two stages, wherein both stages are designed in the form of flow compressors (3, 4) which each have one compressor wheel (8, 9, 10, 11) per stage, wherein the compressor wheels (8, 9; 10, 11) for the one and the other fuel cell system (13; 14) are arranged symmetrically to at least one electrical machine (5, 6) on a shaft (7).

Abstract: The invention relates to a fuel cell system (2) with at least one fuel cell stack (19), which comprises an anode chamber (20) and a cathode chamber (21), with at least one air conveying device (3) for the supply of the cathode chamber (21) with air via a feed air line (22), with an outlet air line (23) from the cathode chamber (21), with at least one fuel supply device (26) for the supply of the anode chamber (20) with fuel, with at least one anode circuit (28) for the recirculation of unused fuel around the anode chamber (20), furthermore with a cathode bypass (37).

Abstract: The invention relates to an air supply device (1) for fuel cell systems (2, 3) with a flow compressor and an electric drive motor (4) for the flow compressor, wherein the flow compressor has two compressor wheels (6, 7) which are essentially symmetrical and which are arranged, together with the electric drive motor (4) there between, on a common shaft (5). The air supply device according to the invention is characterized in that the two compressor wheels (6, 7) are connected on the pressure side to two systems (2, 3, 10, 13) which are pneumatically not permanently connected. A fuel cell system (2, 3) which uses such an air supply device (1) is also claimed.

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

Abstract: A cooling device for a fuel cell system includes at least one cooling circuit, through which a fuel cell can be cooled. The fuel cell system also includes a component with at least an electric drive area and a gas delivery area. A gas can be delivered to the fuel cell through the gas delivery area and the component is actively cooled. The cooling of the component takes place together with the cooling of the fuel cell in a cooling circuit.

Abstract: An apparatus for supplying a fuel cell in a fuel cell system with fuel gas is provided. The fuel cell system includes a mixing region, where unused fuel gas mixes with fresh fuel gas, a water precipitator, a device for the at least indirect heating of the supplied fresh fuel gas and at least one receptor for a sensor for sensing state variables and/or chemical magnitudes of the fuel gas flowing to the anode. The mixing region, water precipitator, device for the at least indirect heating and at least one sensor are combined in an integrated component part.

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