In the areas of traffic and vehicle power units, high energy consumption an resource depletion have led during the past twenty years to improvements to vehicles with Diesel and Otto enigines, improved traffic control, and the development and introduction of alternative power units. One alternative is the fuel cell motor, The advantages of a fuel cell vehicle lie in reduced or zero emission, The electrical efficiency of the fuel cell is very high and not subject to the constraints of the Carnot process, Owing to their technical properties, such as their working temperature range, CO2 compatibility, solid electrolyte in the form of a film, PEM fuel cells appear most suitable for use in vehicles. They can be operated fairly straightforwardly so that the periphery remains well controllable on construction of a complete system, If an alternative power unit such as the fuel cell is to acquire customer acceptance beyond initial niche applications then not only better primary energy consumption and significantly better emmision behavior than conventional drives are required. Further technical an economic demand will have to be meet in order satisfy sutomer expectations.