Abstract: The invention relates to a fuel cell system comprising a housing including a chamber for accommodating a fuel cell stack. The fuel cell system has various features that can also be independently embodied, namely: a U-shaped air channel including air inlet channels and air outlet channels which include an inlet or outlet on the same side of the housing of the fuel cell system; at least two fans or compressors that are disposed downstream of each other in an air flow direction in the air inlet channel or in the air outlet channel; a housing that has two additional, separate housing sections apart from a chamber for a fuel cell stack and an air inlet channel and an air outlet channel; and an air bypass channel which is arranged between an air inlet channel for introducing ambient air into a chamber for the fuel cell stack and an air outlet channel for discharging air from the chamber for the fuel cell stack.

Abstract: The invention relates to a membrane electrode unit for fuel cells. The inventive membrane electrode unit comprises a reinforcing frame that is situated on the periphery and in the area of openings which are placed in the active portion of the membrane electrode unit and provided for guiding material or for installation. Said reinforcing frame is formed by a hot-melt-type adhesive layer that is applied on both sides and is formed by at least one rigid plate. The hot-melt-type adhesive layers which protrude over the outer edge of the membrane electrode unit enter into an intimate bond, due to the effect of pressure and heat, with the rigid plates and with the membrane electrode unit as well as with one another in the projecting area. The hot-melt-type adhesive comprises ionic or strong polar groups which interact with the ionic groups of the polymer electrolyte membrane and which ensure a high degree of adherence between the hot-melt-type adhesive and the membrane electrode unit.

Abstract: The invention relates to a membrane electrode unit which is provided for a fuel cell or the like and which comprises a polymer electrolyte membrane that is coated on both sides with electrodes. The sealing edge which is configured on the outer periphery is comprised of a hot-melt-type adhesive whose hydrocarbon skeleton carries, at regular intervals, ionic or strong polar groups which enter into a surface interaction with the ionic groups of the membrane material and thus provide for a good adhesive effect of the hot-melt-type adhesive to the polymer electrolyte membrane. A portion of the sealing edge that protrudes over the outer edge of the membrane electrode unit forms a one-piece homogeneous edge area which is provided with openings for installation and for guiding media, which further improves the sealing effect of the membrane electrode unit, and which contributes to the stability thereof.

Abstract: In an electrolysis appliance or a reversible fuel cell which can be operated optionally as a fuel cell or as an electrolysis appliance, a gas reservoir is in the form of a one-piece or two-piece, tubular hollow body. The gas reservoir is open at the top and is split into a reservoir area and an expansion area by a separating plug having an immersion tube which passes through it and points downward. In a region of the reservoir area, the gas reservoirs are each fitted directly to the end plates, or are formed integrally with them. Each of the half-cells are connected to a respective reservoir area and to the electrolyte located in it via channels in the end plate and openings in the respective gas reservoir. The electrolysis appliances or fuel cells which are configured to have an integrated gas reservoir formed in such a way are strong and sturdy, are configured to save space, are easy to handle and can be produced at low cost.

Abstract: An experimental apparatus for determining characteristics, including the power, of fuel cells. The apparatus contains at least three and a maximum of 15 resistors, whose resistance correspond to a profile of the characteristic to be expected. In addition, an ammeter and a voltmeter with a maximum of two measurement ranges which are typical of the power range corresponding to one or more fuel cells is provided. This makes it considerably easier to carry out experiments, particularly by trainees with little prior training.

Abstract: A fuel cell stack including bipolar plates disposed between membrane-electrode units. The stack has two end-position monopolar plates. Two current collectors and two end plates enclose the stack on opposite sides said current collectors have at least one collector passage hole with a port end face. The stack includes at least one connection port and substantially annular sealing elements. The two end plates have at least one end plate passage hole communicating with the at least one connection port and the at least one collector passage hole. The sealing elements each have an opening. A single sealing element completely seals the transporting of media between the end face of a connection port and the end-position media-carrying plate by being disposed in the passage holes in the end plate and the current collector for transporting the reaction and cooling media to and from the opening in the adjoining end-position plate.