Abstract: Mass transfer and/or heat transport processes in a fuel-cell stack are controlled by first modeling a selected region of the stack with at least two fluid components separated from one another by solid material. Each fluid component of the selected region is then transformed into a respective auxiliary volume in which all of the fluid components and solid material in the region are assembled additionally and whose outer cell corresponds to that of the region. Then each auxiliary volume is divided into a lattice with individual lattice elements that are linked by references so that linked or coupled lattices result. Finally the exchange between the fluids in the fuel-cell stack is implemented via the references of the respective component lattices.

Abstract: The invention relates to a method of modeling mass transfer and/or heat transport processes in an apparatus, especially in an apparatus comprising at least two fluid spaces like, for example, a high-temperature fuel-cell stack. The invention relates, further, to a computer system for carrying out the method.

Abstract: A fuel cell system is used for on-board power supply in a motor vehicle that is powered by an internal combustion engine. The blower fan that is used to cool the radiator of the engine also cools the fuel cell module and/or it provides the air feed for operating the fuel cell module.

Abstract: A fuel cell system is operated by a supply of fuel and air. The air provides the oxygen required for the operation of the fuel cells in the form of an oxidant. The invention aims to prevent the fuel cell module from damage that might be caused when the motor vehicle is operated in different environments with possibly high pollution levels. To this end, the air is purified before it is supplied to the fuel cell system by way of an air purification device that is associated with the fuel cell module.

Abstract: A fuel cell system is used for on-board power supply in a motor vehicle that is powered by an internal combustion engine. The blower fan that is used to cool the radiator of the engine also cools the fuel cell module and/or it provides the air feed for operating the fuel cell module.

Abstract: A fuel cell stack has a heating device for preheating the feed air with a heat exchanger. The heat exchanger, at least in one dimension of the flat area arrangement, has the same size as the fuel cell stack. This makes it possible for heat exchanger and fuel cell stack to be arranged one behind the other in a simple way and advantageously enables them to be accommodated in a common housing.

Abstract: A smooth operation with different boundary conditions is required in order for fuel cell systems to be practically used in motor vehicles. To this end, the operating temperature of the fuel cell unit is equalized under varying load conditions. This is effected by a latent heat storage that is located upstream from the fuel cell unit in the vehicle, that is, the latent heat storage device extracts energy from or supplies energy to the fuel cell module as needed.

Abstract: A motor vehicle has an electric motor drive and an on-board power supply. Conventional on-board power supply systems can be operated with fuel cell modules. Here, the motor vehicle further comprises an air conditioning system providing cooling air that has an air conditioning compressor supplied by the electric systems of the vehicle. The electric systems can be either the hybrid drive of the motor vehicle or a separate electric motor driven by a fuel cell module already mounted in the vehicle. High-temperature PEM fuel cells are especially suitable for this purpose.

Abstract: Fuel cell units are suitable for continuous energy supply to electrical consumers. Particularly for the application in motor vehicles the above can either be the drive for an electric motor and/or also the supply of other electrical users. Here, a fuel cell module only delivers the electrical energy to a rechargeable battery and not directly to the user. The fuel cell module can thus be permanently held at the optimal operating point thereof. The fuel cell module preferably comprises HT-PEM fuel cells, which in contrast to PEM fuel cells work at a higher temperature, in particular in the range 120 C.° to 200 C.°.

Abstract: A fuel cell system has at least one fuel cell module operating according to the HT-PEM principle. The novel installation renders harmless at least the excess hydrogen gas that accumulates on the hydrogen side of the individual fuel cell unit, by connecting an exhaust gas catalytic converter. Environmental pollution by hydrogen is thus prevented. The catalytic converter may also be enabled to purify carbon monoxide and/or hydrocarbons from the exhaust gas.

Abstract: A fuel cell unit for a vehicle, in particular a motor vehicle, has at least one fuel cell module and/or fuel cell stack. The fuel cell module is mechanically decoupled from the vehicle with damping elements and it is mounted between the floor and an underbody of the vehicle. The fuel cell module may advantageously be a flat stack with PEM fuel cells or HT-PEM cells.

Abstract: HT-PEM fuel cells that are constantly operated at high temperatures are less sensitive to CO contamination than PEM fuel cells that are operated at normal temperatures. It is nevertheless advantageous to regenerate possible CO contamination caused by the starting of the fuel cell. To achieve this, the HT-PEM fuel cell is operated in pulse mode for a predetermined period during the warm-up phase or at operating temperature. This permits the regeneration of the electrodes of the fuel cells, which have CO deposits. To carry out a regeneration method of a control and/or regulation device in a fuel-cell system having at least one fuel cell module that consists of a stack of HT-PEM fuel cells, with a control and/or regulation device for process management allocated thereto, the system is provided with a pulse device, which activates a pulse-mode operation for the fuel-cell stack, in dependence on at least one of several predeterminable parameters.

Abstract: An HT-PEM fuel cell installation is cascaded and the fuel cells are driven in cascade operation. This enables the outlet emissions to be influenced advantageously and undesirable emissions can be reduced to a minimum.

Abstract: A fuel cell stack includes at least two stacked fuel cell units which are held together by a material which has sealing and fixing properties. A method for assembling a fuel cell stack is also provided.

Abstract: A fuel cell installation and a method for operating a fuel cell installation with a dynamic power control are provided. The dynamic power control is achieved by additionally connecting at least one subsystem which is kept ready for operation, a starter system and/or a low-voltage unit for nighttime operation and/or an on-board power supply.

Abstract: High-temperature polymer electrolyte membrane (HTM) fuel cells, installations including HTM fuel cells, methods for operating an HTM fuel cell, and an HTM fuel cell installation apply the principle of the known PEM fuel cell and overcomes the major drawback of this fuel cell. By selecting a new electrolyte and changing the operating conditions, in particular the temperature and the pressure, the fuel cells do not depend on water content.

Abstract: A membrane electrode assembly for a self-humidifying fuel cell, a method of its production, and a self-humidifying fuel cell battery include a membrane electrode assembly with a membrane electrolyte, into which at least one catalyst layer is laminated, so that water can be generated in a controlled manner within the membrane by recombination of the reaction gases H2 and O2.