Abstract: A fuel cell system which has a fuel cell is described. Also provided is a device for producing/preparing the fuel, for example hydrogen, which is connected on its outlet side to a fuel supply line and on its inlet side to a device for supplying fuel. The device for supplying fuel has a dual pump, in which a starting material for the fuel, stored in the motor-fuel tank, and water fed in via a water supply line, which is for example process water produced during the fuel cell process, are mixed to form a fuel/water mixture. This fuel/water mixture is intermediately stored in an intermediate tank before it is fed to the device for producing/preparing the fuel.

Abstract: A fuel cell system which has a fuel cell with a supply line and a discharge line for a fuel as well as a supply line and a discharge line for an oxidizing agent. Also provided is a fuel tank which contains, for example, benzene or methanol for producing the fuel for the fuel cell. To avoid the release of hydrocarbons from the fuel contained in the tank, a filter element, for example an active carbon filter, is connected to the fuel tank. To be able to regenerate the filter element, the filter element is connected to the discharge line for the oxidizing agent and/or the discharge line for the fuel. The filter element is regenerated by the flow of exhaust gas from the fuel cell. The filter element is preferably connected via a connecting line to a burner, with the result that the hydrocarbons taken up by the flow of exhaust gas can be burned in the burner. Furthermore, by designing the fuel cell system appropriately, a leakage diagnosis can also be performed in the fuel tank.

Abstract: A fuel cell system which has a fuel cell is described. Also provided is a device for producing/preparing the fuel, for example hydrogen, which is connected on its outlet side to a fuel supply line and on its inlet side to a device for supplying fuel. The device for supplying fuel has a dual pump, in which a starting material for the fuel, stored in the motor-fuel tank, and water fed in via a water supply line, which is for example process water produced during the fuel cell process, are mixed to form a fuel/water mixture. This fuel/water mixture is intermediately stored in an intermediate tank before it is fed to the device for producing/preparing the fuel.