Volkswagen Ag

Audi Ag

Hannes Scholz

Christian Lucas

Daniel Grundei

Jan-Philipp Brinkmeier

Matthias Reckers

Christian Schlitzberger

Gerold Hübner

Lasse Schmidt

Sebastian Kirsch

Tobias Lösche-Ter Horst

Lutz Lackenmacher

Florian Moll

A fuel cell system includes a fuel cell stack formed from a plurality of cell units, which have gas diffusion layers, wherein the gas diffusion layer of at least one of the edge cell units has a heat transfer mechanism of reduced efficiency in comparison with the gas diffusion layer of a cell unit from the middle of the fuel cell stack. A motor vehicle may include such a fuel cell system.

Fuel cell system having improved gas diffusion layers and motor vehicle having a fuel cell system

A membrane electrode unit has a seal arranged on the edge region, wherein the seal in part penetrates into the edge region of the membrane electrode unit and in part fully covers the edge region outside the membrane electrode unit, which enables sealing of the gas chambers of a fuel cell and at the same time reliably interrupts a leakage path at the edge in membrane electrode units with flush cut. The membrane electrode unit is surrounded by a sealing frame which at least partially surrounds the edge region with the seal.

Membrane electrode unit with a seal arrangement, fuel cell, and fuel cell stack

The invention relates to a bipolar plate for a fuel cell, comprising an anode plate with anode gas channels and a cathode plate with cathode gas channels, said plates having an active region and supply regions and being arranged one over the other such that the gas channels form coolant channels. The aim of the invention is to improve such a bipolar plate such that the flow conditions of reactants and coolant in the bipolar plate are optimized. This is achieved in that the height and/or the width of the cathode gas channels increase(s) from a first side of the active region to a second side of the active region, and the height and/or the width of the anode gas channels decrease(s) from the first side of the active region to the second side of the active region, wherein the cross-sectional area and/or the hydraulic diameter of the cathode gas channels increases, and the cross-sectional area and/or the hydraulic diameter of the anode gas channels decreases. The invention additionally relates to a fuel cell stack and to a vehicle.

Bipolar plate which has reactant gas channels with variable cross-sectional areas, fuel cell stack, and vehicle comprising such a fuel cell stack

A bipolar plate for a fuel cell having two profiled separator plates with channels for reaction gases and coolant, wherein the channels for a reaction gas or both reaction gases have a smaller width in an inlet region of the active region than in the remaining sub-region of the active region, wherein the width thereof continuously increases from the beginning to the end of the inlet region. Supports between the channels have a greater width than in the remaining sub-region of the active region, wherein the sum of the width of the channels and the width of the supports is constant, and the width of the channels and the supports is constant in the entire remaining sub-region.

Bipolar plate having a variable width of the reaction gas channels in the inlet region of the active region, fuel-cell stack and fuel-cell system having bipolar plates of this type, as well as a vehicle

The invention relates to a bipolar plate () for a fuel cell stack. The bipolar plate () respectively has two profiled separator plates () respectively having an active area () and two distribution areas () for supplying and discharging reaction gases and coolant to or from the active area (), wherein the separator plates () are designed and arranged on top of each other such that the respective bipolar plate () has separate channels () for the reaction gases and the coolant, which channels connect ports () for reaction gases and coolant of both distribution areas () to each other. In the mounted fuel cell stack, the channels () for the reaction gases are respectively bordered by a surface of a separator plate () and a surface of a gas diffusion layer (). It is provided that the bipolar plate () have an impermeable first dividing plate (), which respectively divides the channels () for a reaction gas in an inlet area () of the active area () into two volume areas and extends in the flow direction () of the reaction gas, wherein only one volume area of the channel () is adjacent to the gas diffusion layer (). The subject matter of the invention is also a fuel cell stack with such bipolar plates (), as well as a fuel cell system with a fuel cell stack according to the invention.

Bipolar plate and a fuel cell stack comprising same

The invention relates to a separator plate, a membrane electrode assembly and a fuel cell stack, which are designed for higher voltages. It is provided that in the active region at least one of the cell components contains at least one insulating element which permanently enables different electrical potentials in a cell plane (orthogonal to the stacking direction).

Separator plate, membrane electrode assembly and fuel cell

The invention relates to a fuel cell stack having bipolar plates (), each of which has two separator plates () with an active region () and two distribution regions () with main gas ports () as well as a coolant main port (), wherein the separator plates () are formed and arranged one over the other in such a way that the respective bipolar plate () has separate channels () for the reaction gases and the coolant that connect the main gas port () for the reaction gases and the coolant main port () of the two distribution region () to each other. It is provided that the channels () for a reaction gas have an impermeable first dividing plate () in an inlet area () of the active area () that separates the channels () into two volume areas (), and in that a second main gas port () is provided adjacent to the first main gas port () in a distribution region () in order to supply the reaction gas. The subject matter of the invention is also a fuel cell system that has a fuel cell stack according to the invention.

Fuel cell stack having bipolar plates, and fuel cell system

The invention relates to a fuel cell stack (), comprising: &#x2014;bipolar plates (), each having an active region (), wherein a surface of the bipolar plate is formed non-profiled at least in the active region (), &#x2014;a membrane electrode assembly (), arranged between two bipolar plates (), and&#x2014;a gas distribution layer () arranged between the membrane electrode assembly () and at least one of the bipolar plates (), wherein the gas distribution layer () comprises a porous flow body (). It is provided that the gas distribution layer () includes recesses () in the active region ().

Fuel cell and fuel cell stack

A cathode supply () for a fuel cell () of a fuel cell unit () for a fuel cell system is provided, the cathode supply () including a cathode supply path () and a cathode exhaust gas path () and at least two fluid pumping devices () for pumping a cathode operating medium () for the fuel cell () are fluido-mechanically coupled into the cathode supply path (), at least one first fluid pumping device () of the at least two fluid pumping devices () being drivable only on the basis of an enthalpy in a cathode exhaust gas () of the fuel cell (). A fuel cell unit for a vehicle, in particular, an electric vehicle, a fuel cell system for a vehicle, in particular, an electric vehicle, or a vehicle in particular an electric vehicle, the fuel cell unit, the fuel cell system, or the vehicle including a cathode supply () is provided.

Cathode supply for a fuel cell

A membrane electrode assembly and fuel cell having such assembly. The membrane electrode assembly has a polymer electrolyte membrane, two catalytic electrodes in contact with the polymer electrolyte membrane on both sides, namely an anode and a cathode, and two gas diffusion layers directly or indirectly adjoining the electrodes, namely an anode-side gas diffusion layer and a cathode-side gas diffusion layer. At least one of the gas diffusion layers may optionally feature a microporous layer facing the polymer electrolyte membrane. The sequence of layers is anode-side gas diffusion layer, anode-side microporous layer, anode, polymer electrolyte membrane, cathode, cathode-side microporous layer, cathode-side gas diffusion layer. A relative hydrophobicity of at least two of these components and/or a hydrophobicity gradient within at least one of these components, and a relative pore structure having pore size and/or porosity of at least two of these components and/or a gradient within the pore structure of at least one of these components, is designed in such a way that it promotes the transport of water via the polymer electrolyte membrane, preferably from the cathode side to the anode side.

Growing community of inventors

Braunschweig, Germany

Hannes Scholz