Abstract: A fuel cell system is provided having multiple individual fuel cells which are combined to form a fuel cell stack, and having two current collectors which adjoin the two end-side individual fuel cells. The current collectors are each adjoined directly, or with the interposition of an isolation plate, by an end plate. A heat accumulator is provided at least on one of the current collectors so as to adjoin that side of the latter which faces away from the individual fuel cells. The heat accumulator may be arranged in a recess of the end plate, or of an optionally provided isolation plate, and a compensation reservoir for a change in volume of the heat accumulator may be provided.