Abstract: A fuel-cell stack has a first end plate and a second end plate and a plurality of fuel cells arranged between the end plates. At least one elastic tensioning element is tensioned in the stack direction between the end plates. Furthermore, a re-tensioning element is arranged between the tensioning element and a surface section of the fuel-cell stack. The re-tensioning element has a tensioning body and at least one adjusting element arranged between the tensioning body and the surface section. A distance between the tensioning body and the surface section can be variably adjusted and fixed by the at least one adjusting element.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one tensioning or tensile element is tensioned in the stack direction between the end plates. Inlet and outlet ports for operating resources are arranged in first end areas of the first end plates and in second end areas of the second end plates. At least one additional elastic tensioning element is tensioned between first end areas and/or second end areas of the end plates.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one elastic tensioning element is tensioned in the stack direction between the end plates. Furthermore, the fuel cell stack has at least one rotatably mounted mounting shaft. At least one end section of at least one tensioning element is fixed to the rotating mounting shaft. Moreover, the rotatable mounting shaft is connected to the fuel cell stack via a tensioned torsion spring. The torsion spring brings about an automatic retensioning of the tensioning element.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one elastic tensioning element is tensioned in a stack direction between the end plates. According to the invention, a section of the at least one tensioning element is arranged between a surface section of the fuel cell stack and a retensioning element, wherein a distance between the retensioning element and the surface section can be variably adjusted and set. In this way, the tensioning element can be stretched in a targeted manner by means of the retensioning element and as such the compressive tensile force acting on the fuel cell stack can be increased. A vehicle is also provided comprising such a fuel cell stack.

Abstract: In order to provide a bipolar plate for a fuel cell, providing an anode plate with an anode side and a coolant side, wherein a first structuring for forming an anode flow field is formed on the anode side, and a cathode plate with a cathode side and a coolant side, wherein a second structuring for forming a cathode flow field is formed on the cathode side; wherein structural elements, which are contacted by the coolant sides of the anode plate and the cathode plate, for forming a coolant flow field, are arranged between the anode plate and the cathode plate, which bipolar plate has an optimized pressure distribution in a fuel cell stack and increased stability in comparison with the prior art, it is proposed that the structural elements may be made of an elastic material and that the structural elements have a different height in different regions of the coolant flow field. A fuel cell stack and a vehicle are also disclosed.

Abstract: Embodiments of the invention relate to a membrane-electrode assembly comprising a membrane structure with an anode layer, a cathode layer, and a membrane layer, wherein the membrane layer is positioned between the anode layer and the cathode layer. The membrane-electrode assembly furthermore comprises an anode-side gas-diffusion layer arranged on the anode layer and a cathode-side gas-diffusion layer arranged on the cathode layer. Furthermore, at least one of the anode-side gas-diffusion and the cathode-side gas-diffusion layers has a structure on the side facing away from the membrane structure. According to some embodiments, the structure comprises a plurality of columns for forming a laterally-open flow field, wherein the columns have support surfaces for supporting a bipolar plate.

Abstract: A fuel cell stack is provided comprising membrane electrode assemblies and bipolar plates for supplying the membrane electrode assemblies with operating media and coolant, wherein a first bipolar plate comprises flow pathways having path depths that are different from path depths of corresponding flow pathways of a second bipolar plate. Moreover, a vehicle with a fuel cell system having such a fuel cell stack is provided.

Abstract: A bipolar plate for a fuel cell, is provided having an anode plate with an anode side and a coolant side, wherein there is formed on the anode side a first structuring in order to form an anode flow field, and a cathode plate with a cathode side and a coolant side, wherein there is formed on the cathode side a second structuring to form a cathode flow field, there being arranged between the anode plate and the cathode plate structural elements to form a coolant flow field, being contacted from the coolant sides of the anode plate and the cathode plate, and having an optimized pressure distribution in a fuel cell stack and an increased stability as compared to the prior art. The structural elements consist of an elastic material. A fuel cell stack and a vehicle including such features are also provided.

Abstract: The invention relates to a bipolar plate (15) for a fuel cell stack (10) comprising a first sealing section (157) on its side (151) as well as a second sealing section (158) on its second side. The sealing sections are designed to sealingly interact in a fuel cell stack (10) with an elastic seal element (16). It is provided that the first and second sealing sections of the bipolar plate (15) are designed asymmetrically in that at least one sealing projection (1571) is formed in the first sealing section (157), and the second sealing section (158) is formed without a sealing projection and/or is substantially flat. When such bipolar plates (15) alternatingly interact with seal elements (6) that are designed flat in a fuel-cell stack (10), an effective stack seal can be achieved with low required contact pressure.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one elastic tensioning element is tensioned in a stack direction between the end plates. According to the invention, a section of the at least one tensioning element is arranged between a surface section of the fuel cell stack and a retensioning element wherein a distance between the retensioning element and the surface section can be variably adjusted and set. In this way, the tensioning element can be stretched in a targeted manner by means of the retensioning element and as such the compressive tensile force acting on the fuel cell stack can be increased. A vehicle is also provided comprising such a fuel cell stack.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one elastic tensioning element is tensioned in the stack direction between the end plates. Furthermore, the fuel cell stack has at least one rotatably mounted mounting shaft. At least one end section of at least one tensioning element is fixed to the rotating mounting shaft. Moreover, the rotatable mounting shaft is connected to the fuel cell stack via a tensioned torsion spring. The torsion spring brings about an automatic retensioning of the tensioning element.

Abstract: A fuel cell stack is provided comprising a first end plate and a second end plate between which a plurality of fuel cells is arranged. At least one tensioning or tensile element is tensioned in the stack direction between the end plates. Inlet and outlet ports for operating resources are arranged in first end areas of the first end plates and in second end areas of the second end plates. At least one additional elastic tensioning element is tensioned between first end areas and/or second end areas of the end plates.

Abstract: A fuel-cell stack has a first end plate and a second end plate and a plurality of fuel cells arranged between the end plates. At least one elastic tensioning element is tensioned in the stack direction between the end plates. Furthermore, a re-tensioning element is arranged between the tensioning element and a surface section of the fuel-cell stack. The re-tensioning element has a tensioning body and at least one adjusting element arranged between the tensioning body and the surface section. A distance between the tensioning body and the surface section can be variably adjusted and fixed by means of the at least one adjusting element.

Abstract: Embodiments of the invention relate to a membrane-electrode assembly comprising a membrane structure with an anode layer, a cathode layer, and a membrane layer, wherein the membrane layer is positioned between the anode layer and the cathode layer. The membrane-electrode assembly furthermore comprises an anode-side gas-diffusion layer arranged on the anode layer and a cathode-side gas-diffusion layer arranged on the cathode layer. Furthermore, at least one of the anode-side gas-diffusion and the cathode-side gas-diffusion layers has a structure on the side facing away from the membrane structure. According to some embodiments, the structure comprises a plurality of columns for forming a laterally-open flow field, wherein the columns have support surfaces for supporting a bipolar plate.

Abstract: In order to provide a bipolar plate for a fuel cell, providing an anode plate with an anode side and a coolant side, wherein a first structuring for forming an anode flow field is formed on the anode side, and a cathode plate with a cathode side and a coolant side, wherein a second structuring for forming a cathode flow field is formed on the cathode side; wherein structural elements, which are contacted by the coolant sides of the anode plate and the cathode plate, for forming a coolant flow field, are arranged between the anode plate and the cathode plate, which bipolar plate has an optimized pressure distribution in a fuel cell stack and increased stability in comparison with the prior art, it is proposed that the structural elements may be made of an elastic material and that the structural elements have a different height in different regions of the coolant flow field. A fuel cell stack and a vehicle are also disclosed.

Abstract: The invention relates to a polar plate for a fuel cell, comprising at least one single plate with two opposing main sides, wherein the single plate has, on at least one of its main sides: elevations and free spaces arranged therebetween, which form a flow structure for an operating medium of the fuel cell; and spring projections which are arranged on the elevations and are designed to yield in case of a force effect taking place orthogonally to the main sides. Furthermore, the invention relates to a fuel cell stack with a polar plate according to the invention.

Abstract: The invention relates to a polar plate assembly for a fuel cell, comprising: a polar plate which comprises, on at least one of its flat sides, elevations and free spaces arranged between them, which form a flow structure for a reactant; and a supporting structure designed to prevent or at least reduce an intrusion by a gas diffusion layer adjacent to the supporting structure and/or a membrane electrode assembly into the free spaces of the flow structure. It is provided that the polar plate assembly is designed such that the polar plate protrudes into the supporting structure. The invention furthermore relates to an individual cell with a polar plate assembly according to the invention.

Abstract: The invention relates to a bipolar plate (15) for a fuel cell stack (10) comprising a first sealing section (157) on its side (151) as well as a second sealing section (158) on its second side. The sealing sections are designed to sealingly interact in a fuel cell stack (10) with an elastic seal element (16). It is provided that the first and second sealing sections of the bipolar plate (15) are designed asymmetrically in that at least one sealing projection (1571) is formed in the first sealing section (157), and the second sealing section (158) is formed without a sealing projection and/or is substantially flat. When such bipolar plates (15) alternatingly interact with seal elements (6) that are designed flat in a fuel-cell stack (10), an effective stack seal can be achieved with low required contact pressure.

Abstract: The invention relates to a polar plate for a fuel cell, comprising at least one single plate with two opposing main sides, wherein the single plate has, on at least one of its main sides: elevations and free spaces arranged therebetween, which form a flow structure for an operating medium of the fuel cell; and spring projections which are arranged on the elevations and are designed to yield in case of a force effect taking place orthogonally to the main sides. Furthermore, the invention relates to a fuel cell stack with a polar plate according to the invention.

Abstract: The invention relates to a polar plate assembly for a fuel cell, comprising: a polar plate which comprises, on at least one of its flat sides, elevations and free spaces arranged between them, which form a flow structure for a reactant; and a supporting structure designed to prevent or at least reduce an intrusion by a gas diffusion layer adjacent to the supporting structure and/or a membrane electrode assembly into the free spaces of the flow structure. It is provided that the polar plate assembly is designed such that the polar plate protrudes into the supporting structure. The invention furthermore relates to an individual cell with a polar plate assembly according to the invention.