Abstract: The invention relates to a method for operating an electric drive system of a motor vehicle (2) with a backup battery (2.8) and a fuel cell (2.6) for providing electric drive power. Here, route data is determined and then, based on this route data, consumption data is forecast. The invention is characterized in that, in order to optimize the operation of the fuel cell (2.6) based on the forecast consumption data, a total energy demand for the route is forecast, after which a mean fuel cell power is determined which is required together with the energy stored at the starting time of the route in the backup battery (2.8) to determine the total energy demand over a constant power trajectory for the fuel cell (2.6). This is followed by a check as to whether limit values of the backup battery (2.8) are violated when driving along the route with the power trajectory: if no limit value is violated, the fuel cell (2.

Abstract: The invention relates to a method for preparing to refuel a tank in a vehicle with hydrogen, for which purpose the tank pressure is lowered in preparation for driving to a filling station, wherein the filling station is informed of the pending refueling. The method according to the invention is characterized in that the refueling takes place with liquid hydrogen, wherein the maximum achievable pressure level of the tank during refueling, the expected pressure level of the tank when the filling station is reached, and the expected refueling quantity are transmitted to the filling station.