Abstract: A fuel cell assembly with at least one PEM fuel cell for generating electrical energy from reactant gases includes at least one membrane/electrode having a membrane coated with platinum electrodes and, respectively positioned on each side, a porous gas diffusion layer, or having a membrane and, respectively positioned on each side, a porous gas diffusion layer coated with a platinum electrode, and also includes bipolar plates that lie against the gas diffusion layers and through which, during operation, a coolant flows, wherein at least one of the platinum electrodes has a smaller area than the gas diffusion layer, where the gas diffusion layer protrudes beyond the platinum electrode for a part of an edge region of the membrane/electrode unit, so that the formation of an electrochemical potential in this part of the edge region of the membrane/electrode unit is prevented in order to prevent damage to the membrane.

Abstract: A fuel cell assembly with at least one proton exchange membrane (PEM) fuel cell for generating electrical energy from the reactant gases hydrogen and oxygen, which includes at least one membrane/electrode unit having a membrane that is coated with platinum electrodes and, respectively positioned on each side thereof, a porous gas diffusion layer, or which has a membrane and, respectively positioned on each side thereof, a porous gas diffusion layer that is coated with a platinum electrode, and which includes bipolar plates that lie against the gas diffusion layers and through which, during operation, a coolant flows, where access by at least one of the reactant gases to the membrane is blocked by a mechanical block for a part of an edge region of the membrane/electrode unit In order to prevent damage to the membrane.

Abstract: A fuel cell assembly with at least one PEM fuel cell for generating electrical energy from reactant gases includes at least one membrane/electrode having a membrane coated with platinum electrodes and, respectively positioned on each side, a porous gas diffusion layer, or having a membrane and, respectively positioned on each side, a porous gas diffusion layer coated with a platinum electrode, and also includes bipolar plates that lie against the gas diffusion layers and through which, during operation, a coolant flows, wherein at least one of the platinum electrodes has a smaller area than the gas diffusion layer, where the gas diffusion layer protrudes beyond the platinum electrode for a part of an edge region of the membrane/electrode unit, so that the formation of an electrochemical potential in this part of the edge region of the membrane/electrode unit is prevented in order to prevent damage to the membrane.

Abstract: A fuel cell assembly with at least one proton exchange membrane (PEM) fuel cell for generating electrical energy from the reactant gases hydrogen and oxygen, which includes at least one membrane/electrode unit having a membrane that is coated with platinum electrodes and, respectively positioned on each side thereof, a porous gas diffusion layer, or which has a membrane and, respectively positioned on each side thereof, a porous gas diffusion layer that is coated with a platinum electrode, and which includes bipolar plates that lie against the gas diffusion layers and through which, during operation, a coolant flows, where access by at least one of the reactant gases to the membrane is blocked by a mechanical block for a part of an edge region of the membrane/electrode unit In order to prevent damage to the membrane.

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 method for operating a fuel cell stack which includes a number of fuel cells and at least one gas circuit, where the fuel cells are supplied on the gas inlet side with oxygen and hydrogen as reaction gases, and where at least oxygen is circulated in the fuel cells via the gas circuit, so as to provide a fuel cell stack with a simple structure and reliable intergas removal.

Abstract: A humidification cell of a fuel cell apparatus includes a first outer plate and a second outer plate. A gas chamber, a humidification water chamber, and a water-permeable membrane that separates 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 is disposed between the first outer plate and the membrane. The first support element is made of a woven fabric formed of a plastic. A discharge and an entrainment of liquid water can be prevented during load changes or other non-stationary fuel cell operating states accompanied by a sudden change of gas volume flow in that the plastic is a fluoropolymer or a fluoroplastic. Advantageously, the fluoropolymer or fluoroplastic is formed at least partly, preferably entirely, of an alternating copolymer of ethylene and chlorotrifluorethylene (E-CTFE).

Abstract: The invention relates to a contact device which is arranged in a terminal compartment of a fuel cell stack and is used to electrically contact the fuel cell stack. According to the invention, the surface of said contact device is at least partially provided with a hydrophobic surface layer, facilitating the removal of water, e.g., condensation water, from the terminal compartment and thus from the fuel cell stack.

Abstract: The invention relates to a bipolar plate, for fuel cells, characterized in comprising a layer of a hydrophobic material which is soluble in a solvent, on the surfaces thereof. Water forms small droplets on the surfaces of the bipolar plate due to said layer, which are loosely held on the surface of the bipolar plate and which can be reliably removed from the fuel cell even with low flow speeds for the operating gases. The thickness of the layer and thus the hydrophobicity thereof and the electrical contact resistance between the bipolar plate and a contacting electrode may be adjusted in a simple manner, by varying the concentration of the hydrophobic material in the solvent.

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: The invention relates to a bipolar plate, for fuel cells, characterised in comprising a layer of a hydrophobic material which is soluble in a solvent, on the surfaces thereof. Water forms small droplets on the surfaces of the bipolar plate due to said layer, which are loosely held on the surface of the bipolar plate and which can be reliably removed from the fuel cell even with low flow speeds for the operating gases. The thickness of the layer and thus the hydrophobicity thereof and the electrical contact resistance between the bipolar plate and a contacting electrode may be adjusted in a simple manner, by varying the concentration of the hydrophobic material in the solvent.

Abstract: The invention relates to a bipolar plate, for fuel cells, including a layer of a hydrophobic material which is soluble in a solvent, on the surfaces thereof. Water forms small droplets on the surfaces of the bipolar plate due to said layer, which are loosely held on the surface of the bipolar plate and which can be reliably removed from the fuel cell even with low flow speeds for the operating gases. The thickness of the layer and thus the hydrophobicity thereof and the electrical contact resistance between the bipolar plate and a contacting electrode may be adjusted in a simple manner, by varying the concentration of the hydrophobic material in the solvent.

Abstract: The invention relates to a contact device which is arranged in a terminal compartment of a fuel cell stack and is used to electrically contact the fuel cell stack. According to the invention, the surface of said contact device is at least partially provided with a hydrophobic surface layer, facilitating the removal of water, e.g., condensation water, from the terminal compartment and thus from the fuel cell stack.

Abstract: The invention relates to a bipolar plate, for fuel cells, characterised in comprising a layer of a hydrophobing material which is soluble in a solvent, on the surfaces thereof. Water forms small droplets on the surfaces of the bipolar plate due to said layer, which are loosely held on the surface of the bipolar plate and which can be reliably removed from the fuel cell even with low flow speeds for the operating gases. The thickness of the layer and thus the hydrophobicity thereof and the electrical contact resistance between the bipolar plate and a contacting electrode may be adjusted in a simple manner, by varying the concentration of the hydrophobing material in the solvent.

Abstract: When a fuel cell installation is switched off, there is danger that residual oxygen remains in the fuel cells of the fuel cell installation. The residual oxygen results in undesired oxidations that considerably limit the output and life-time of the fuel cell installation. The aim is therefore to make sure that enough hydrogen remains in the fuel cells to bring the entire oxygen within the fuel cells to an electrochemical reaction when the fuel cell installation is switched off. To this end, the fuel cell installation in which the anode gas chamber adjoining the anodes of the fuel cells is at least twice as big as the cathode gas chamber adjoining the cathodes of the fuel cells.

Abstract: In a process for photolithographic generation of structures in the sub-200 nm range, a layer of amorphous hydrogen-containing carbon (a-C:H) with an optical energy gap of <1 eV or a layer of sputtered amorphous carbon (a-C) is applied as the bottom resist to a substrate (layer thickness .ltoreq.500 nm); the bottom resist is provided with a layer of an electron beam-sensitive silicon-containing or silylatable photoresist as the top resist (layer thickness .ltoreq.50 nm); the top resist is structured by means of scanning tunneling microscopy (STM) or scanning force microscopy (SFM) with electrons of an energy of .ltoreq.80 eV; and then the structure is transferred to the bottom resist by etching with an anisotropic oxygen plasma and next is transferred to the substrate by plasma etching.

Abstract: A fuel cell with a proton-conducting membrane, on which catalyst material and a collector are arranged on both sides, is characterized by the following features: on the side facing the membrane (14), the collectors (16,18) are provided with an electrically conductive gas-permeable carbon aerogel with a surface roughness of <2 .mu.m; a catalyst layer (15, 17) of platinum or a platinum alloy is in each case applied to the carbon aerogel by material bonding; and a membrane (14), deposited by plasma-chemical means, with a layer thickness of between 3 and 50 .mu.m, is located between the catalyst layers (15, 17).

Abstract: A semiconductor component has a semiconductor body with at least on pn-junction therein, extending to the surface of the semiconductor body, and has a passivation layer composed of boron-doped, amorphous, hydrogenous carbon (A-C:H) which covers at least the portion of the pn-junction extending to the surface, the boron content of the passivation layer being between 0.1 per mil and 4% by weight. The passivation layer is manufactured on the semiconductor body by deposition from a high-frequency, low-pressure plasma which is generated in a mixture of gaseous, organic compounds containing carbon and hydrogen and gaseous, organic boron compounds.

Abstract: Multilayer printed circuit boards and multichip-module substrates having at least one layered composite of high-temperature-stable plastic and conductive tracks wherein the plastic is provided with a thin layer of amorphous, hydrogenated carbon (a--C:H) having a water permeation coefficient of <1.1.times.10.sup.-13 m.sup.2 /s. The a--C:H-layer also has a hardness gradient across it.

Abstract: A method for manufacturing multichip modules having layer sequences made of dielectric material with conducting tracks embedded therein is characterized by the following features: (1) a temperature-resistant, base-resistant polymer having a dielectric constant .ltoreq.3 is used as a dielectric material, which is applied to a non-conductive substrate and serves as an edge boundary for currentless, autocatalytic build-up of the conducting tracks; (2) the dielectric material is provided with a layer made of material which is soluble in organic solvents (lift-off layer); (3) the dielectric material and the lift-off layer are structured in a single lithographic step, either a direct or an indirect structuring taking place and grooves having an aspect ratio .gtoreq.