Abstract: A fuel cell installation includes a cascaded fuel cell block, for essentially waste gas-free operation. An installation of this type presents the problem that the cascaded fuel cell block is complex to produce and therefore expensive. To solve this problem, the fuel cell installation has several steps which are arranged in a cascade, each of the steps comprising one or more non-cascaded similar fuel cell blocks. A fuel cell installation construction including modular similar fuel cell blocks is economical and simple to produce in series.

Abstract: A fuel cell installation includes a cascaded fuel cell block, for essentially waste gas-free operation. An installation of this type presents the problem that the cascaded fuel cell block is complex to produce and therefore expensive. To solve this problem, the fuel cell installation has several steps which are arranged in a cascade, each of the steps comprising one or more non-cascaded similar fuel cell blocks. A fuel cell installation construction including modular similar fuel cell blocks is economical and simple to produce in series.

Abstract: A motor vehicle built-in unit for a mobile phone has a central control unit and an interface for exchanging signals between the central control unit of the mobile phone and the motor vehicle. The built-in unit also has a motor vehicle-specific adapter control unit for adapting functions of the interface and/or of the central control unit to the respective type of motor vehicle. The modular design allows for electrical and mechanical adaptation to various types of motor vehicles so that the central control unit and interface can be identical for a wide variety of motor vehicles. An alternative built-in unit has a central unit and an interface for connecting to the motor vehicle. The interface is designed to connect the built-in unit to the motor vehicle selectively either with a standardized plug-type connector or a motor vehicle-specific plug-type connector. The motor vehicle built-in unit can therefore easily be adapted to the type of plug which is used in the respective motor vehicle.

Abstract: A fuel cell system having a fuel cell block is operated by compressing an operating agent for the fuel cell block with a liquid ring compressor. After compressing the operating agent, water is separated from the operating agent in an apparatus for water separation. The fuel cell block is cooled with the water and, after the cooling, at least a portion of the water is fed back into the apparatus for water separation. This measure reduces the number of components which form the fuel cell system.

Abstract: A method is provided for operating a PEM fuel cell plant containing at least one PEM fuel cell block and a speed-controlled compressor upstream of the PEM fuel cell block for supplying air at a volume flow rate. The speed of the compressor is controlled to a desired value for adjusting the electric current of the PEM fuel cell block to a given value. The desired value is derived from the given value of the electric current. This measure ensures a simple control of the air volume flow rate for the PEM fuel cell block with low apparatus requirements. A PEM fuel cell plant is also provided.

Abstract: A process for operating a PEM fuel cell unit containing at least one PEM fuel cell block and a speed-controlled compressor connected upstream. To control changing an electrical current I of the PEM fuel cell block to a new reference value I.sub.SN, a speed n of the compressor is set in a first step to a maximum value n.sub.M and in a second step is reduced to a speed n.sub.SN corresponding to the new reference value I.sub.SN. By this expedient improved dynamics for brief and rapid load changes are achieved.

Abstract: A catalyst for converting higher hydrocarbons, in particular for converting such hydrocarbons into gas mixtures containing carbon monoxide, methane and/or hydrogen in which the active component oxides of the metals lanthanum, cobalt, nickel, uranium, cerium and thorium are placed on an oxide substrate, preferably a sintered body of magnesium oxide or aluminum oxide to result in a catalytic structure particularly useful with internal combustion engines for motor vehicles.