Abstract: A fuel cell module includes a plurality of fuel cells, which are connected one behind the other and which are combined to form a fuel cell stack. The fuel cell module should be designed in such a manner that the magnetic field or leakage field, which can be detected in the outer area and which is generated during the operation of the fuel cell module, is held at a particularly low level. To this end, the materials used for providing the fuel cells themselves, the materials used for producing the connecting components or auxiliary components, which are assigned thereto, that connect these fuel cells, and the materials used for producing the housing are selected that have a relative magnetic permeability of less than 1.1.

Abstract: A fuel cell module includes a number of series-connected fuel cells which collectively form a fuel cell stack in such a way that the magnetic field or stray field that is generated during the operation of the fuel cell module and that is detectable in an outer area is kept particularly small. To this end, the invention provides that a number of shielding lines that are connected to a first pole flange of the fuel cell stack are provided, these shielding lines being guided on the outer area of the fuel cell stack, as far as a contact area to a second pole flange of the fuel cell stack.

Abstract: A leak in a fuel cell module can allow hydrogen and/or oxygen to escape from the fuel cell module, thereby creating a high risk of fire or explosion. This problem is addressed by providing a fuel cell installation with a fuel cell module that is enclosed in a gas-tight pressure container. Filling the pressure container with a protective gas ensures that if the fuel cell module does leak, no operating gas can escape from the module, with protective gas entering the module instead. A leak therefore no longer poses a risk. The leak can also be identified and located by a voltage drop in the cells affected by the leak.

Abstract: A device connects at least two fuel cell batteries. Moreover, a plant includes the device. In order to connect a plurality of batteries containing fuel cells in a clearly understandable way and for easy mounting, each battery is assigned a junction block with T-pieces. The T-pieces in each case form a stub line to a collecting line and are coupled to the battery or (for example, via connecting elements) to one another via flanges. The flanges are preferably integrated to form junction flange plates and coupling flange plates.

Abstract: The composite conductor plate of a low-temperature fuel cell poses the following problem: it must be extremely corrosion-resistant to pure oxygen that is humidified by water and to pure hydrogen and must at the same time be able to be processed mechanically. To solve the problem, a composite conductor plate contains 50 to 60 wt. % Ni, 12 to 22 wt. % Cr, 10 to 18 wt. % Mo, 4 to 10 wt. % Fe and 0.5 to 5 wt. % W.

Abstract: A fuel cell module includes a number of series-connected fuel cells which collectively form a fuel cell stack in such a way that the magnetic field or stray field that is generated during the operation of the fuel cell module and that is detectable in an outer area is kept particularly small. To this end, the invention provides that a number of shielding lines that are connected to a first pole flange of the fuel cell stack are provided, these shielding lines being guided on the outer area of the fuel cell stack, as far as a contact area to a second pole flange of the fuel cell stack.

Abstract: A leak in a fuel cell module can allow hydrogen and/or oxygen to escape from the fuel cell module, thereby creating a high risk of fire or explosion. This problem is addressed by providing a fuel cell installation with a fuel cell module that is enclosed in a gas-tight pressure container. Filling the pressure container with a protective gas ensures that if the fuel cell module does leak, no operating gas can escape from the module, with protective gas entering the module instead. A leak therefore no longer poses a risk. The leak can also be identified and located by a voltage drop in the cells affected by the leak.

Abstract: Gas chambers (7, 9) in fuel cells (1) are sealed from the environment in a gas-tight manner by means of seals (11). Said seals (11) are exposed to the chemically very aggressive operating gases at high temperature. According to the invention, a fuel cell (1), has a seal (11), arranged between two components (3, 5), made from a carbon-filled, bisphenol cross-linked fluororubber. Said seal (11) is chemically and mechanically extremely stable, such that each fuel cell (1), in a fuel cell block can be sealed and maintained in position within the fuel cell block by means of single seal (11) in a simple manner.

Abstract: The composite conductor plate of a low-temperature fuel cell poses the following problem: it must be extremely corrosion-resistant to pure oxygen that is humidified by water and to pure hydrogen and must at the same time be able to be processed mechanically. To solve the problem, a composite conductor plate contains 50 to 60 wt. % Ni, 12 to 22 wt. % Cr, 10 to 18 wt. % Mo, 4 to 10 wt. % Fe and 0.5 to 5 wt. % W.

Abstract: A fuel cell module includes a plurality of fuel cells, which are connected one behind the other and which are combined to form a fuel cell stack. The fuel cell module should be designed in such a manner that the magnetic field or leakage field, which can be detected in the outer area and which is generated during the operation of the fuel cell module, is held at a particularly low level. To this end, the materials used for providing the fuel cells themselves, the materials used for producing the connecting components or auxiliary components, which are assigned thereto, that connect these fuel cells, and the materials used for producing the housing are selected that have a relative magnetic permeability of less than 1.1.

Abstract: A device connects at least two fuel cell batteries. Moreover, a plant includes the device. In order to connect a plurality of batteries containing fuel cells in a clearly understandable way and for easy mounting, each battery is assigned a junction block with T-pieces. The T-pieces in each case form a stub line to a collecting line and are coupled to the battery or (for example, via connecting elements) to one another via flanges. The flanges are preferably integrated to form junction flange plates and coupling flange plates.

Abstract: A process for operating a PEM fuel cell installation includes providing at least one PEM fuel cell module having an inlet valve for hydrogen H.sub.2 and an inlet valve for oxygen O.sub.2. In order to switch off the PEM fuel cell module, the oxygen O.sub.2 inlet valve is closed in a first step, and the hydrogen H.sub.2 inlet valve is closed in a second step when a predetermined oxygen O.sub.2 partial pressure at a cathode part of the PEM fuel cell module is reached. Reliable operation of the PEM fuel cell installation is guaranteed by this measure.

Abstract: A fundamental problem which exists in fuel cells having an electrolyte that conducts oxygen ions, hydroxide ions or protons, is that of moistening air of combustion gases for preventing the electrolyte from drying out or thinning and thus preventing defective operation of the fuel cell during air operation. The construction and financial cost, in particular, for moistening of the air is of concern in such a device. In a low-temperature fuel cell, in particular a PEM fuel cell, and a method for moistening the electrolyte of the fuel cell, according to the invention, that disadvantage is avoided by providing that exhaust gas which occurs on the cathode side of the fuel cell is at least partially recirculated into the cathode of the fuel cell. Consequently, the water content of the electrolyte can be set within wide limits by simple adjustment of the recirculated exhaust-gas quantity. Therefore, economical use of the PEM fuel cell becomes possible.

Abstract: A method for cathode-side water and inert gas disposal and/or anode-side inert gas disposal from a fuel cell block having a number of fuel cells, includes increasingly concentrating a water and an inert gas component in a cathode-side gas mixture and an inert gas component in an anode-side gas mixture, in flow direction of the gas mixtures. The water and inert gas components are at least partially discharged from the fuel cell block. In an apparatus for performing the method, the fuel cells are subdivided into cell groups through which a flow of gas mixtures can be conducted in parallel. The cell groups include a cell group disposed last as seen in gas mixture flow direction. Lines connect the cell groups for conducting at least a fraction of the gas mixtures successively through the cell groups, and for discharging another fraction of the gas mixtures, being dependent on an electric current, from the fuel cell block after flowing through the last cell group.

Abstract: A component for installation in a process control apparatus, such as a fuel cell block, includes two mutually parallel plates having inner surfaces facing toward each other and outer surfaces facing away from each other. Generally flat components resting on the outer surfaces of the plates define a first chamber with one of the outer surfaces and a second chamber with the other of the outer surfaces at two sides of the component. The inner surfaces of the plates enclose a third gas-tight chamber therebetween. At least one gas-tight channel extends between the plates in the plane of the plates. The at least one gas-tight channel has an inlet end communicating with an antechamber and a discharge end to be connected to at least one of the first, second and third chambers as needed.

Abstract: In a method for adjusting the removal of inert gas from a fuel cell block having a number of fuel cells, a progressive rise in a proportion of inert gas results in a cathode-side or anode-side gas mixture flowing through the fuel cells. An inert-gas-rich gas mixture is drained out as a function of a voltage drop, and the voltage drop is measured between at least two immediately adjacent fuel cells. A fuel cell block includes a number of adjacent fuel cells having electrodes and gas chambers. At least one bipolar plate contacts the electrodes of adjacent fuel cells over a large area. Two spaced-apart contacts are disposed between at least two of the adjacent fuel cells on the at least one bipolar plate. A control element for a gas mixture leaving one of the gas chambers and having a high proportion of inert gas, is adjusted by a voltage drop picked up at the contacts.

Abstract: A current connection device for use in batteries formed from a plurality of electrochemical cells wherein the electrodes in each cell are to have pressure cushions for isostatic compression and the cells are to operate at increased pressure levels. The device comprises two contact sheets welded to the sides of a metal plate, one to a side, the metal plate with its contact sheets being surrounded by an elastomer frame. A metallic current connection strip is coupled to the plate and extends through the frame to permit coupling the cells together.

Abstract: An electric dc source with fuel cells or fuel batteries connected in series or in series and parallel, not only gives quiet operation, but does so without a large power electronics system, by providing a separate gas supply to each fuel cell or fuel battery and disposing controllable valves in the gas supply lines and connecting outputs having a given polarity of the series connected fuel cells or fuel batteries to a bus bar of the same polarity via electric valves.

Abstract: A process for operating a PEM fuel cell installation includes providing at least one PEM fuel cell module having an inlet valve for hydrogen H2 and an inlet valve for oxygen O2. In order to switch off the PEM fuel cell module, the oxygen O2 inlet valve is closed in a first step, and the hydrogen H2 inlet valve is closed in a second step when a predetermined oxygen O2 partial pressure at a cathode part of the PEM fuel cell module is reached. Reliable operation of the PEM fuel cell installation is guaranteed by this measure.

Abstract: A method for cathode-side water and inert gas disposal and/or anode-side inert gas disposal from a fuel cell block having a number of fuel cells, includes increasingly concentrating a water and an inert gas component in a cathode-side gas mixture and an inert gas component in an anode-side gas mixture, in flow direction of the gas mixtures. The water and inert gas components are at least partially discharged from the fuel cell block. In an apparatus for performing the method, the fuel cells are subdivided into cell groups through which a flow of gas mixtures can be conducted in parallel. The cell groups include a cell group disposed last as seen in gas mixture flow direction. Lines connect the cell groups for conducting at least a fraction of the gas mixtures successively through the cell groups, and for discharging another fraction of the gas mixtures, being dependent on an electric current, from the fuel cell block after flowing through the last cell group.