fuel cells

Abstract

A fuel cell (1) comprising at least one membrane, at least one anode electrode layer, at least one cathode electrode layer, at least two gas diffusion layers, and at least two flow field structures, wherein the at least one membrane (2) is disposed between one anode electrode layer (3) and one cathode electrode layer (4) to form a membrane electrode assembly and define active areas (Aij), one gas diffusion layer (5) is disposed adjacent to each electrode layer (3; 4), and one flow field structure (6; 7) is disposed adjacent to each gas diffusion layer (5). a fuel cell (1) arranged in a manner such that each flow field structure (6; 7) comprises at least three fuel manifolds (90), at least three oxidant manifolds (91) and at least three coolant manifolds (92), said fuel cell (1) comprising at least two active areas (A11; A12), at least one fuel manifold (90), at least one oxidant manifold (91) and at least one coolant manifold (92) being arranged between said at least two active areas (A11, A12).

Description

[Technical Field]

[0001] The present invention relates to fuel cells, and in particular to fuel cell modules. [Background technology]

[0002] Fuel cells are electrochemical devices that convert hydrogen energy into electricity and have attracted considerable attention in recent years as a clean energy source that can replace fossil fuels. There are several types of fuel cells under development, which are primarily classified based on the materials they are made of and their operating temperature. Polymer electrolyte membrane fuel cells (PEMFCs) are one of the best candidates for mobile and automotive applications as well as stationary applications due to their high power density and compactness.

[0003] A single cell in a PEMFC consists of a thin electrolyte, an anode catalyst layer, and a cathode catalyst layer; the assembly is called a Membrane Electrode Assembly (MEA). Fuel (usually hydrogen) passes through one side of the membrane, and oxidant (usually air) passes through the other side, where an electrochemical reaction occurs, producing electricity and water as by-products. Current technology allows for a maximum current of 2 to 3 A / cm. 2 ] and a current density of 4 to 5 [W / m 3 ] can be achieved. To increase these values ​​and improve the performance of fuel cells, it is necessary to work on compact dimensions. The main parameters that play a key role in the operation of a fuel cell stack are the pressure drop across the fuel cell stack, oxygen utilization (oxygen depletion), phase change and water management, and membrane dehydration. The influence of these parameters becomes more insignificant when the stack operates under dynamic and load modulation conditions. For example, such fuel cells are known from WO 2019 / 207811, US 2019 / 0221868 and US 2019 / 0214654. Summary of the Invention [Means for solving the problem]

[0004] The problem to be solved by the present invention is to increase the current and volumetric power density. Values ​​of 6 to 7 kW / L or more are possible with the present invention. Furthermore, the manufacturing method of the fuel cell according to the present invention is simplified and significantly improved.

[0005] This problem is solved by a fuel cell having the features of claim 1. Further embodiments of the fuel cell are defined by the features of the further claims.

[0006] A fuel cell according to the present invention includes at least one membrane, at least one anode electrode layer, at least one cathode electrode layer, at least two gas diffusion layers, and at least two flow field structures. The at least one membrane is disposed between one anode electrode layer and one cathode electrode layer to form a membrane electrode assembly and define active areas. One gas diffusion layer is disposed adjacent to each electrode layer, and one flow field structure is disposed adjacent to each gas diffusion layer. Each flow field structure includes at least three fuel manifolds, at least three oxidant manifolds, and at least three coolant manifolds. The fuel cell includes at least two active areas, and the at least one fuel manifold, at least one oxidant manifold, and at least one coolant manifold are disposed between the at least two active areas.

[0007] With this design, the media supply is divided into many branches that enter and exit small sections of the active area, called "segments," that are independent of the other sections. In other words, the active area of ​​a single cell is divided into several smaller active areas where fluid enters and exits at specific locations on the cell. The fluid can be a gas (generally a gas), such as air, hydrogen, or a liquid (deionized water, antifreeze, etc.), whether humidified or not.

[0008] Referring to fuel cell theory, the "reversible open circuit voltage" of a hydrogen fuel cell is defined by the "Nernst" equation, which states that the cell voltage is directly correlated to the oxygen partial pressure. This means that the utilization and depletion of oxygen in the cell leads to a decrease in the cell voltage. In the gas flow path, oxygen consumption from the inlet to the outlet decreases the cell voltage, lowering the average cell voltage. However, current approaches help overcome this problem by introducing new fluid between the segmented active regions. Therefore, at each entry point, the cell voltage increases, and therefore the average cell voltage increases.

[0009] Another advantage of the present invention is that segmenting the active area of ​​the cell shortens the gas flow path and therefore significantly reduces the pressure drop across each segment compared to conventional approaches. Therefore, with a fuel cell according to the present invention, it is possible to operate the stack using a blower instead of a compressor, thus providing a fuel cell system with reduced parasitic loads.

[0010] Another advantage of cell segmentation is that it makes thermal management of the cell easier, since the segments are smaller and temperature variations are more uniform and replicated within the active area, allowing for more flexibility in determining the cell's outer dimensions without affecting performance.

[0011] This concept can be explained in more detail by comparing it with a state-of-the-art design. 2 Consider an automotive stack with a typical size, 30 cm long, 10 cm wide, and a gas flow path length of 30 cm. Under nominal operating conditions, a pressure drop of approximately 20-50 kPa and a temperature change of 5-8°C are expected between the inlet and outlet of the flow path, i.e., between the inlet and outlet of the cell. Furthermore, the utilization of oxidant and fuel and the management of water are limited by the shape and length of the flow path.

[0012] By segmenting the cell, the gas flow path can be divided into several sections with a flow path length as short as 5 cm, resulting in a smaller pressure drop (linear relationship, i.e., one-fifth) and a smaller temperature difference between the inlet and outlet, resulting in better durability, easier water management, and oxidant utilization. Furthermore, the cell can be expanded to 30 × 10 cm without affecting performance. 2 ] or 20 × 15 [cm 2 ] or other configurations.

[0013] In one embodiment, at least one of each of the three manifolds is an inlet manifold and at least two of them are outlet manifolds, or alternatively, at least two of the three manifolds are inlet manifolds and at least one of them is an outlet manifold.

[0014] In one embodiment, the number of outlet manifolds is twice the number of inlet manifolds. Alternatively, the number of inlet manifolds is twice the number of outlet manifolds.

[0015] In one embodiment, the cross-sectional size of all of the manifolds is the same, or the cross-sectional size of at least one of the manifolds is different from the size of the other manifolds.

[0016] In one embodiment, the cross-sectional shape of all of the manifolds is the same, or the cross-sectional shape of at least one of the manifolds is different from the shape of the other manifolds.

[0017] In one embodiment, the shape of the manifold is one of the group including angular, rectangular, square, oval, and circular, however, any shape is possible.

[0018] In one embodiment, for each of the three manifolds, the total cross-sectional area of ​​all the inlet manifolds is equal to the total cross-sectional area of ​​all the outlet manifolds.

[0019] In one embodiment, for each of the three manifolds, the total cross-sectional area of ​​all of the inlet manifolds is greater than the total cross-sectional area of ​​all of the outlet manifolds, or, alternatively, for each of the three manifolds, the total cross-sectional area of ​​all of the inlet manifolds is less than the total cross-sectional area of ​​all of the outlet manifolds.

[0020] In one embodiment, the total cross-sectional area of ​​the fuel manifolds is equal to the total cross-sectional area of ​​the oxidizer manifolds and / or the total cross-sectional area of ​​the coolant manifolds.

[0021] In one embodiment, the total cross-sectional area of ​​the fuel manifolds is greater than the total cross-sectional area of ​​the oxidizer manifolds and / or the total cross-sectional area of ​​the coolant manifolds, or alternatively, the total cross-sectional area of ​​the fuel manifolds is less than the total cross-sectional area of ​​the oxidizer manifolds and / or the total cross-sectional area of ​​the coolant manifolds.

[0022] In one embodiment, the fuel cell includes a pattern of manifolds that repeats itself in at least a first direction, or alternatively, the pattern repeats itself in the first direction and in a second direction perpendicular to the first direction.

[0023] In one embodiment, the distance between two repeating patterns is the same as the distance between two adjacent manifolds in the pattern, or alternatively, the distance between two repeating patterns is greater than the distance between two adjacent manifolds in the pattern.

[0024] In one embodiment, the fuel cell includes at least two gaskets, one gasket positioned adjacent each flow field structure, and each gasket includes the same number of manifolds as flow field structures in the same locations.

[0025] In one embodiment, the fuel cell includes at least one subgasket that covers at least the boundary area on both sides of the membrane, or alternatively, the subgasket covers at least the boundary area of ​​the membrane and electrode layer on both sides.

[0026] In one embodiment, the subgasket extends laterally across the interface between the membrane and the electrode layer.

[0027] In one embodiment, a fuel cell comprises several membrane electrode assemblies, several gas diffusion layers and several flow field structures aligned with one another to form a stack.

[0028] In one embodiment, the fuel cell comprises two current collector plates and two backing plates, one current collector plate positioned adjacent to each flow field structure and one backing plate positioned adjacent to each current collector plate.

[0029] In one embodiment, the clamping element supports two backing plates.

[0030] The features of the fuel cell embodiments described above may be used in any combination not inconsistent with one another. [Brief explanation of the drawings]

[0031] Embodiments of the invention are described in more detail below with reference to the drawings, which are for illustrative purposes only and are not limiting.

[0032] [Figure 1] 1 shows a fuel cell according to the prior art; [Figure 2] FIG. 2 is a diagram showing the behavior of the fuel cell of FIG. [Figure 3] 2 is a cross-sectional view of the fuel cell of FIG. 1 taken along line XX. [Figure 4] 1 is a schematic top view of a first embodiment of a fuel cell according to the present invention; [Figure 5] FIG. 5 is a diagram showing the behavior of the fuel cell of FIG. [Figure 6] 5 is a cross-sectional view of the fuel cell of FIG. 4 taken along line YY. [Figure 7] FIG. 2 is a schematic top view of a second embodiment of a fuel cell according to the present invention. [Figure 8]FIG. 4 is a schematic top view of a third embodiment of a fuel cell according to the present invention. [Figure 9] FIG. 10 is a partial schematic top view of a fourth embodiment of a fuel cell according to the present invention. [Figure 10] FIG. 10 is a partial schematic top view of a fifth embodiment of a fuel cell according to the present invention. [Figure 11] FIG. 10 is a partial schematic top view of a sixth embodiment of a fuel cell according to the present invention. [Figure 12A] 1 is a schematic cross-sectional view of a first embodiment of a subgasket. [Figure 12B] FIG. 10 is a schematic cross-sectional view of a second embodiment of a subgasket. DETAILED DESCRIPTION OF THE INVENTION

[0033] FIG. 1 shows a prior art fuel cell 1 having a conventional membrane electrode assembly (MEA) with one active area A and gas inlet / outlet manifolds 90, 91, and 92. The active area A of the cell is located at its center, and the gas inlet / outlet manifolds 90, 91, and 92 are located around its periphery. Distribution channels 61 for uniform gas distribution exist between the active area A and the inlet manifolds 90, 91, and 92, and collection channels for collecting gas exist between the active area A and the outlet manifolds 90, 91, and 92, which are primarily integrated into the bipolar plates. The MEA and bipolar plates shown have a rectangular shape. The active area A includes flow field channels 62 extending from the inlet side to the outlet side of the cell.

[0034] Figure 2 illustrates the operation of the fuel cell of Figure 1. Key parameters that affect fuel cell performance are pressure drop, humidity, temperature, and fuel / oxidant utilization. Air is typically composed of 21% oxygen and 79% nitrogen and is humidified before entering the cell. In this diagram, the Y-axis represents the percentage partial pressure of oxygen and the X-axis represents the length of the gas flow path, with X(O2) being 21% at the inlet and X(O2) being approximately 15% at the outlet. X(O2) at the outlet varies based on the cell performance, the current drawn from the cell, and the stoichiometry of the air entering the cell. For example, at high current densities (+2.0 [A / cm2]),2 ]), oxygen depletion increases, and at lower stoichiometric ratios, cell performance decreases toward the end of the channel. The second curve represents the pressure drop and temperature rise across the channel. The longer or narrower the channel, the greater the pressure loss. Therefore, the parasitic load on the compressor or blower at the system level increases. At nominal operating conditions, a pressure drop of approximately 20-50 kPa and a temperature rise of 5-8°C between the channel inlet and outlet, and therefore the cell, is expected. For mobile applications, a 300 cm wide cell with a width of 10 cm and a channel length of 30 cm is suitable. 2 ] is the typical size of the active area. The cross-sectional dimensions of the channels produced by pressing technology are limited to about 0.2-0.3 cm. The overall performance of the cell is degraded by large pressure drops, high gas velocities, water management, and oxidant / fuel utilization.

[0035] Figure 3 shows a cross-section of the fuel cell of Figure 1 taken along line XX. The fuel cell 1 comprises a membrane 2 sandwiched between an anode electrode layer 3 and a cathode electrode layer 4. A gas diffusion layer 5 is disposed adjacent to each of the electrode layers 3, 4. A flow field structure 6, 7 is disposed adjacent to each of the gas diffusion layers 5. Each flow field structure 6, 7 comprises connecting channels 61, 71, flow field channels 62, 72, cooling channels 63, 73, and manifolds 90, 91. A gasket 8 is disposed between the flow field structures 6, 7 to laterally seal the fuel cell. The manifolds 90, 91 extend through the flow field structures 6, 7 and the gasket 8.

[0036] FIG. 4 shows a schematic top view of a first embodiment of a fuel cell 1 according to the present invention. It includes two segments, each with an active area A11, A12. Manifolds 90, 91, and 92 are positioned on the sides of the cell between two adjacent active areas A11, A12. Fuel flows from a fuel manifold 90 between the two active areas A11, A12, through each of the two active areas, and to fuel manifolds 90 on either side of the two active areas. Oxidant flows from one oxidizer manifold 91 between the two active areas to two oxidizer manifolds 91 on either side of the two active areas. Coolant flows from two lateral coolant manifolds 92 to an intermediate coolant manifold 92. In the illustrated embodiment, all coolant manifolds 92 are aligned with each other, and the central fuel manifold 90 is aligned with the two lateral oxidizer manifolds 91, which in turn are aligned with the two lateral fuel manifolds 90. In another embodiment, all of the manifolds of the same type may be aligned with each other, or none at all.

[0037] Figure 5 shows the effect of the fuel cell design of the present invention on the behavior of the fuel cell of Figure 4, i.e., oxidant / fuel utilization. The double curve represents the cathode inlet / outlet and oxygen utilization within the single, straight gas channel of a conventional fuel cell. The solid line represents the cathode inlet / outlet and oxygen utilization within the gas channel of a fuel cell of the present invention. Apart from the main gas inlet and outlet, there is an additional inlet and outlet point, which reduces pressure loss, increases oxygen concentration, and therefore improves fuel cell performance. Furthermore, temperature variations are reduced and gas distribution is enhanced. In this example, fresh gas is supplied between the two active regions. Compared to a conventional fuel cell, the length of the active region is divided in half. For a conventional 30 cm length, the length shown corresponds to approximately 15 cm. The number and length of segments vary depending on the geometry, dimensions, and other requirements. For example, a 30 cm long gas channel with one inlet and one outlet can be divided into several smaller channels, each 5 cm long.

[0038] Figure 6 shows a cross section of the fuel cell of Figure 4 along line YY. The fuel cell 1 has essentially the same design as that of Figure 3. Additionally, spacers 60, 70 are positioned in the center of the cell between the membrane 2 and the corresponding flow field structures 6, 7. In this cross section, an oxidant manifold 91 extends through the membrane 2, the spacers 6, 7, and the flow field structures 6, 7. Similarly, the fuel manifold and cooling manifold extend through these components.

[0039] FIG. 7 shows a schematic top view of a second embodiment of a fuel cell according to the present invention. The cell is divided into several segments. The segments are identified as follows: S(ij) is used for reference, where (i) represents the horizontal position of each segment in the (X) direction and (j) represents the vertical position in the (Y) direction. For example, S(12) would be the second segment in the first row. The size and number of segments in a cell are not limited to those shown in the figure (i.e., 12 segments). The number of horizontal and vertical segments can be changed independently of each other without affecting the operation and performance of the other segments. This allows for easy modification of the cell shape from a square to a rectangle, or even a substantially rectangular shape with a very large ratio of horizontal to vertical sides. The ratio of the number of segments in the X direction to the number of segments in the Y direction can vary between 0.001 and 1000, more precisely between 0.1 and 10. Each segment S(ij) includes a corresponding active area A(ij). The illustrated embodiment with mixed flow configurations in different regions of the cell is for illustrative purposes only. To maintain consistent performance throughout the cell, it is preferable to keep the flow configuration similar or identical in all segments. Segments S(11) through S(41) have a counterflow configuration, i.e., fuel gas and oxidant gas flow in opposite directions. The oxidant, in this case air, enters these segments from two separate oxidant manifolds 91 and exits these segments through two separate oxidant manifolds 91. The fuel, in this case hydrogen, enters these segments from one single fuel manifold 90 and exits through two separate fuel manifolds 90. Similarly, the coolant enters these segments from one single coolant manifold 92 and exits through two separate coolant manifolds 92. In the illustrated embodiment, segments S(13) through S(43) have a parallel flow configuration, i.e., fuel gas and oxidant gas flow in the same direction. Manifolds 90, 91, and 92 between two adjacent segments supply gas to both of these segments.

[0040] 8 shows a schematic top view of a third embodiment of a fuel cell according to the present invention, which includes a space between two rows of segments. There are various reasons for providing such a space, such as gas manifolds or current collector passages. From a manufacturing perspective, the intermediate space can be made of a subgasket, a special resin, or a catalyst coated membrane (CCM) that can be left in place.

[0041] Figure 9 shows a partial schematic top view of a fourth embodiment of a fuel cell according to the present invention. Manifolds 90, 91, and 92 direct gases in specific directions and use sealants to restrict gas flow at the edges of the cells. However, each CCM can be divided into several smaller sections using additional blocked flow channels made of bipolar plate structures or special resins or built into subgaskets.

[0042] FIG. 10 shows a partial schematic top view of a fifth embodiment of a fuel cell according to the present invention. Gas manifolds 90, 91, and 92 can have any shape, such as circular, elliptical, square, or rectangular. For rectangular manifolds such as those shown in FIG. 10, the ratio M / N (manifold length / manifold width) can vary between 0.01 and 10, but is not limited thereto. Furthermore, the widths of the gas manifolds are not necessarily the same and can be adjusted based on the design. However, it is recommended to maintain a consistent pattern across all segments. Another possible option is to use larger manifolds for the inlets and smaller manifolds for the outlets, or vice versa. In this case, it is assumed that each inlet manifold 90, 91, and 92 is located between two adjacent segments, with the outlets being smaller than the inlets, or vice versa. The dimensions of the manifolds depend on the size of the cells and the number of segments dividing the cells. Those skilled in the art can perform the necessary calculations and design to appropriately determine the dimensions of the manifolds based on their expectations.

[0043] FIG. 11 shows a partial schematic top view of a sixth embodiment of a fuel cell according to the present invention. In this embodiment, the fuel manifold 90 and coolant manifold 92 are moved toward the sides of each segment and repeated throughout the cell. The illustrated design is a crossflow configuration, i.e., the fuel flow direction is essentially perpendicular to the oxidant flow direction. Depending on the design of the respective flow field channels, the crossflow configuration can be converted to a parallel or counterflow configuration. The cathode inlet and outlet manifolds are expanded to form a more rectangular shape at the top and bottom of each segment. As with the previous configurations, the inlet or outlet manifolds can be shared or unshared between segments. Furthermore, manifolds from only one stream can be moved laterally. For example, the cooling manifolds can be located on the left and right sides of each segment, while the cathode and fuel manifolds can be located side-by-side at the top and bottom of each segment. The dimensions of the active area, and therefore the CCM, are not limited for any embodiment. The active area can preferably have a square, rectangular, or any other shape, although a square or rectangular shape is preferred. For rectangular layouts, the ratio CL / CW (length of CCM / width of CCM) can vary between 0.01 and 100, but there is no limit.

[0044] FIG. 12A shows a schematic cross-sectional view of a first embodiment of a subgasket, and FIG. 12B shows a schematic cross-sectional view of a second embodiment of a subgasket. There are several standard techniques for manufacturing membrane electrode assemblies (MEAs) for PEM fuel cells, which will not be described here. However, any design can be implemented for cell production based on current innovations. There are no limitations on the thickness and materials used for the catalyst-coated membrane (CCM), gas diffusion layer (GDL), and frame / subgasket surrounding the CCM. For example, the subgasket can be made of various thermoplastics, such as PTFE, PET, PEN, or resin, and can also include sealing materials on both sides. In the embodiment of FIG. 12A, the membrane is further stretched, and there is only overlap between the membrane and the subgasket, not the catalyst. The subgasket embodiment of FIG. 12B shows overlap between the frame / subgasket and the CCM, meaning that the membrane and catalyst layers are sandwiched by the subgasket. The subgasket can be attached to the membrane or CCM using various methods, including, but not limited to, lamination, gluing, and fusing. These are for demonstration purposes and other configurations or approaches can be used. Another possibility is to apply the sealing directly to the CCM or membrane. [Explanation of symbols]

[0045] 1 fuel cell 2 membrane 3. Anode electrode layer 4. Cathode electrode layer 5 Gas diffusion layer 6 First flow field structure 60 spacer 61 Connecting channel 62 Flow Field Channel 63 Cooling Channel 7 Second flow field structure 70 spacer 71 Connecting Channel 72 Flow Field Channel 73 Cooling Channel 8 Gaskets 80 Subgasket 81 Subgasket 90 fuel manifold 91 Oxidizer manifold 92 Coolant manifold A(ij) active region S(ij) segment

Claims

1. A fuel cell (1) comprising at least one membrane (2), at least one anode electrode layer (3), at least one cathode electrode layer (4), at least two gas diffusion layers (5), and at least two flow field structures (6; 7), wherein the at least one membrane (2) is disposed between one anode electrode layer (3) and one cathode electrode layer (4) to form a membrane electrode assembly and define an active area (Aij), and one gas diffusion layer (5) is disposed between each electrode layer (3; 4). ), one flow field structure (6; 7) is arranged adjacent to each gas diffusion layer (5), each flow field structure (6; 7) including at least three fuel manifolds (90), at least three oxidant manifolds (91) and at least three coolant manifolds (92), the fuel cell (1) is divided into at least two active areas (A11; A12), there is one active area (A11; A12) per segment of the fuel cell (1). at least one fuel manifold (90), at least one oxidant manifold (91) and at least one coolant manifold (92) are arranged between the at least two active areas (A11, A12) and thereby between the segments of the fuel cell (1), so as to provide a pattern of manifolds (90; 91; 92) that repeats itself at least twice in a first direction (X) and at least twice in a second direction (Y) perpendicular to the first direction (X); gaskets (8) are arranged between the flow field structures (6; 7) to laterally seal the fuel cell (1); spacers (60; 70) are arranged between the segments of the fuel cell (1), the spacers (60; 70) extend between the membrane (2) and the corresponding flow field structures (6; 7), and fresh fuel, oxidant and coolant, respectively, can be introduced between the segments of the fuel cell (1).

2. at least one of the fuel manifolds (90) is an inlet manifold and at least two of the fuel manifolds (90) are outlet manifolds, or at least two of the fuel manifolds (90) are inlet manifolds and at least one of the fuel manifolds (90) is an outlet manifold; and At least one of the oxidizer manifolds (91) is an inlet manifold and at least two of the oxidizer manifolds (91) are outlet manifolds, or at least two of the oxidizer manifolds (91) are inlet manifolds and at least one of the oxidizer manifolds (91) is an outlet manifold; and 2. The fuel cell (1) of claim 1, wherein at least one of the coolant manifolds (92) is an inlet manifold and at least two of the coolant manifolds (92) are outlet manifolds, or at least two of the coolant manifolds (92) are inlet manifolds and at least one of the coolant manifolds (92) is an outlet manifold.

3. 3. The fuel cell (1) according to claim 2, wherein the number of outlet manifolds is twice the number of inlet manifolds, or the number of inlet manifolds is twice the number of outlet manifolds.

4. 4. A fuel cell (1) according to any one of claims 1 to 3, wherein all manifolds (90; 91; 92) have the same cross-sectional size, or wherein the cross-sectional size of at least one of the manifolds (90; 91; 92) is different from the size of the other manifolds.

5. 5. A fuel cell (1) according to any one of claims 1 to 4, wherein all manifolds (90; 91; 92) have the same cross-sectional shape or the cross-sectional shape of at least one of the manifolds differs from the shape of the other manifolds.

6. 6. The fuel cell (1) according to claim 5, wherein the manifold (90; 91; 92) has an angular, rectangular, square, oval or circular shape.

7. For said fuel manifold (90), the total cross-sectional area of ​​all fuel inlet manifolds is equal to the total cross-sectional area of ​​all fuel outlet manifolds; and For said oxidant manifold (91), the total cross-sectional area of ​​all oxidant inlet manifolds is equal to the total cross-sectional area of ​​all oxidant outlet manifolds; and 7. The fuel cell (1) according to any one of claims 2 to 6, wherein for the coolant manifolds (92), the total cross-sectional area of ​​all coolant inlet manifolds is equal to the total cross-sectional area of ​​all coolant outlet manifolds.

8. For the fuel manifold (90), the total cross-sectional area of ​​all fuel inlet manifolds is greater than the total cross-sectional area of ​​all fuel outlet manifolds, or for the fuel manifold (90), the total cross-sectional area of ​​all fuel inlet manifolds is less than the total cross-sectional area of ​​all fuel outlet manifolds; and For the oxidant manifold (91), the total cross-sectional area of ​​all oxidant inlet manifolds is greater than the total cross-sectional area of ​​all oxidant outlet manifolds, or for the oxidant manifold (91), the total cross-sectional area of ​​all oxidant inlet manifolds is less than the total cross-sectional area of ​​all oxidant outlet manifolds; and 7. A fuel cell (1) as described in any one of claims 2 to 6, wherein, for the coolant manifold (92), the total cross-sectional area of ​​all coolant inlet manifolds is greater than the total cross-sectional area of ​​all coolant outlet manifolds, or, for the coolant manifold (92), the total cross-sectional area of ​​all coolant inlet manifolds is less than the total cross-sectional area of ​​all coolant outlet manifolds.

9. 9. The fuel cell (1) of claim 2, wherein the total cross-sectional area of ​​the fuel manifolds (90) is equal to the total cross-sectional area of ​​the oxidizer manifolds (91) and / or the total cross-sectional area of ​​the fuel manifolds (90) is equal to the total cross-sectional area of ​​the coolant manifolds (92).

10. 9. The fuel cell (1) of claim 2, wherein the total cross-sectional area of ​​the fuel manifolds (90) is greater than the total cross-sectional area of ​​the oxidizer manifolds (91) and / or the total cross-sectional area of ​​the fuel manifolds (90) is greater than the total cross-sectional area of ​​the coolant manifolds (92), or the total cross-sectional area of ​​the fuel manifolds (90) is smaller than the total cross-sectional area of ​​the oxidizer manifolds (91) and / or the total cross-sectional area of ​​the fuel manifolds (90) is smaller than the total cross-sectional area of ​​the coolant manifolds (92).

11. 2. The fuel cell (1) of claim 1, wherein the distance between two repeating patterns is the same as the distance between two adjacent manifolds (90; 91, 92) in the pattern, or the distance between two repeating patterns is greater than the distance between two adjacent manifolds (90; 91; 92) in the pattern.

12. 12. A fuel cell (1) according to any one of claims 1 to 11, comprising at least two gaskets (8), one gasket (8) positioned adjacent to each flow field structure (6; 7), each gasket (8) comprising the same number of manifolds (90; 91; 92) as there are flow field structures (6; 7) in the same position.

13. 13. A fuel cell (1) according to any one of claims 1 to 12, comprising at least one subgasket (80; 81), said subgasket (80; 81) covering at least the boundary area of ​​said membrane (2) on both sides, or said subgasket (80; 81) covering at least the boundary area in the area of ​​said membrane (2) and said electrode layer (3; 4) on both sides.

14. 14. The fuel cell (1) according to claim 13, wherein the subgasket (81) extends laterally across the interface between the membrane (2) and the electrode layer (3; 4).

15. 15. A fuel cell (1) according to any one of the preceding claims, comprising several membrane electrode assemblies, several gas diffusion layers (5) and several flow field structures (6; 7) aligned with one another to form a stack.

16. 16. A fuel cell (1) according to any one of claims 1 to 15, comprising two current collector plates and two backing plates, one current collector plate being positioned adjacent to each flow field structure (6; 7) and one backing plate being positioned adjacent to each current collector plate.

17. 17. The fuel cell (1) according to claim 16, comprising clamping elements supporting the two backing plates.

18. 18. The fuel cell (1) according to any one of the preceding claims, which is operable with a blower.

19. A fuel cell (1) as described in any one of claims 1 to 18, characterized in that the oxidant contains oxygen and the percentage of partial pressure of oxygen in the oxidant exceeds 15% across the fuel cell (1).

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