Device for equalizing concentration variations in fuel cell systems

Apparatus for leveling out the concentration swings of a gas component in a combustion gas stream in a dynamically-operated fuel cell system (1) is such that there is included 'in-line' a buffer unit (10) containing a material which adsorbs or absorbs gas components showing a partial pressure-dependent uptake capacity. Apparatus for leveling out the concentration swings of a gas component of a combustion gas stream in a dynamically-operated fuel cell system (1) is such that a buffer unit (10) is provided upstream of and 'in-line' with of one of the protective units (2, 3, 4, 7, 9) of the system (1), this unit (10) removing the gas component when there is an increase in the partial pressure and releasing it back into the stream when the partial pressure falls. The characteristic feature is that unit (10) contains a material which adsorbs or absorbs gas components showing a partial pressure-dependent uptake capacity.