Method for producing fuel cell with different power outputs and corresponding fuel cell

Abstract

The invention relates to a method for manufacturing a plurality of types of fuel cells having different power outputs according to the cell type, said cells comprising a stack of plates, each plate comprising a first channel for the circulation of a reaction gas and a second channel for the circulation of a heat transfer fluid, the reaction gases are hydrogen and air, respectively, and a proton exchange membrane is placed between two adjacent plates, according to which:-a plate of a single specification is obtained; obtaining at least two types of films, the at least two types of films having at least two film specifications, each film specification having a different size; assembling a plate with a membrane of a first one of said membrane specifications to produce a fuel cell of a first type having a first power output; assembling the plate with a membrane of a second one of said membrane specifications to produce a fuel cell of a second type having a second power output, so that a plurality of types of cells having different power outputs can be obtained using the same plate and membrane for each type of cell, each of a given type of cells uses a membrane of the same specification for the type of cells.

Description

1. Technical Field

[0001] The field of the invention is that of hydrogen fuel cells. More precisely, the invention relates to improvements in such fuel cells and in particular to improvements in the bipolar plates and monopolar plates used to form fuel cells.

[0002] Such panels and such batteries have uses in many areas wherever electrical energy needs to be generated, in particular independently, for example in vehicles (motor vehicles, utility vehicles, trucks, buses, trains, ships, aircraft, etc.), engine generators, etc.

[0003] In particular, the present invention relates to the manufacture of batteries that deliver a power output suitable for an application or given need in an efficient and economical manner. 2. Background technology

[0004] The principle of fuel cells has been known for many years. They are used in particular in the aerospace sector and are also being developed in many projects by various vehicle manufacturers.

[0005] Hydrogen fuel cells are based on Figure 1 The principle shown in the figure is 2 ) and oxygen (O 2 ) produces electrical energy. The chemical reaction is described by the following formula:

[0006] [Chemical formula 1]H 2 -->2H + +2e -

[0007]

[0008] Optional term Δ r H < 0 simply means that the reaction is exothermic.

[0009] The reaction takes place in the so-called active zone of the electrolyte membrane and electrodes (MEA, i.e. “Membrane Electrode Assembly”), that is, a stack of H + The ion exchange membrane is located between the anode, which receives hydrogen from the tank, and the anode, which receives oxygen (O 2 ) between the cathodes.

[0010] like Figure 1 As shown, the fuel hydrogen (H 2 ) is introduced (F1) into the cell and contacts the anode A. A portion of the hydrogen permeates (F2) into the anode A, where the hydrogen molecules are separated into e - The electrons and H pass through the electrolyte E toward the cathode C + ions. The cathode is in contact with air brought in from the outside (F3), and the O 2 Oxygen molecule (F4) and H+ Ions and e - The electrons combine to produce (F5) water (H 2 O). The water (F6) and unused air (F7) are discharged.

[0011] Therefore, the anode A is the element where oxidation occurs: H 2 →2H + +2e - , and the cathode C is the element that undergoes reduction: O 2 +4H + +4e - →2H 2 O.e - The electrons circulate between the anode A and the cathode C (F8), generating an electric current E which is used to drive a motor and / or charge a battery pack.

[0012] The reaction is exothermic and the various elements forming the battery can heat up quickly. The entire system must therefore be cooled. Therefore, the mechanical parts must be designed to be supplied with a coolant or heat transfer fluid.

[0013] Figure 2 The structure of the fuel cell that realizes this chemical reaction is shown. The battery 21 is placed on two end plates 23 1 and 23 2 The stacked pieces of unit cells 22 therebetween.

[0014] Figure 3 The elements forming the unit cell 22 are described in detail in an exploded view. It comprises two types of plates, bipolar or monopolar, between which an electrolyte membrane is placed. The monopolar plates are the first and last plates of the unit cell stack. They generally have the same design as the bipolar plates, but the input ends are closed so that the plates do not receive one of the gases. Thus, the unit cell comprises a cathode monopolar plate that does not receive hydrogen and an anode monopolar plate that does not receive oxygen.

[0015] The bipolar plate superimposed between two monopolar plates consists of an assembly of two metal half-plates 31, 32 (anode half-plate 31 and cathode half-plate 32) which can be welded, brazed or glued. The space between the two metal half-plates is defined by the formation of the two metal half-plates, on the one hand defining the zones 33, 34 receiving the coolant and on the other hand defining channels allowing the circulation of gases, respectively hydrogen and oxygen (extracted from the air). The membrane MEA 35 is inserted between the half-plates.

[0016] These plates are designed to be assembled and form a battery with a defined power output. The design of the battery is complex and specific. The designer of each plate must design that plate specifically to deliver the required power.

[0017] Depending on the application, different powers may be required. Therefore, a number of suitable plates need to be designed. This design requires precise characterization of the plate and its various elements, especially the shape and size of the channels, to obtain the required strength at the terminals of the battery in the most efficient way possible. Then a special tool needs to be developed for manufacturing each plate. This is expensive and complicated. 3. Summary of the invention

[0018] The present invention proposes a solution that allows to simplify the manufacture of cells with various power outputs or intensities at a constant voltage and reduce the manufacturing costs in the form of a method for manufacturing multiple types of fuel cells, which delivers different power outputs depending on the type of the cell, the fuel cell comprising a stack of plates, each plate comprising a first channel for the circulation of a reaction gas and a second channel for the circulation of a heat transfer fluid, the reaction gases being hydrogen and air respectively, and a proton exchange membrane being placed between two adjacent plates.

[0019] The present invention implements the following steps:

[0020] - Get boards of a single format;

[0021] - obtaining at least two types of membranes, the at least two types of membranes having at least two membrane specifications, each membrane specification having a different size;

[0022] - assembling the plate with a membrane of a first one of the membrane specifications to produce a fuel cell of a first type delivering a first power output;

[0023] - assembling said plate with a membrane of a second one of said membrane specifications to produce a fuel cell of a second type delivering a second power output,

[0024] It is thereby possible to employ the same plates and membranes for each type of cell to obtain multiple types of cells that deliver different power outputs, each cell of a given type of cell implementing a membrane having the same specifications for that type of cell.

[0025] Thus, a plate having a single format and at least two membranes each having different sizes is implemented and the plate is assembled with the membranes of one of the membrane formats to produce at least two types of fuel cells delivering different power outputs from the same plate.

[0026] Thus, multiple types of cells can be obtained and the cell used can be effectively adjusted as required using a single type of plate simply by changing the specifications of the membrane. Multiple types of cells can thus be produced quickly and simply without the need to design and produce individual types of plates, which is complicated and costly. Furthermore, economies of scale can be achieved in manufacturing these plates for multiple cell power outputs.

[0027] For all these plates, each type of cell is equipped with the same type of membrane (the type of membrane differs only from cell to cell). Industrial benefits are achieved by reducing the complexity and production costs of multiple types of cells.

[0028] According to a particular embodiment, the first channel and the second channel of the plate extend in orthogonal directions (D1, D2) along the length and width of the plate, respectively, and at least two membranes of the type have the same height, thereby covering all of the first channel above a portion of the length of the plate.

[0029] Each type of cell thus uses all of the first channels or reaction channels over all or part of its length, depending on the power output required. Depending on the type of cell, the membrane may not cover all of the second channels carrying the heat transfer fluid.

[0030] The term "height" of the membrane is used to denote the distance according to the direction in which the first channel extends.

[0031] According to a particular embodiment, the first channels all have the same pattern along the direction D1 .

[0032] The geometry of the channels of the plate is thus adapted to allow optimized use of the same plate for each membrane format, in particular for formats which use the entire height of the plate.

[0033] Of course, other specifications and other sizes are also possible upon request.

[0034] In order to carry out the method effectively, it is desirable to design the plates to ensure substantially constant diffusion of the reaction gases and the heat transfer fluid in the zone coinciding with the membrane used, regardless of the surface area of ​​the zone coinciding with the membrane used.

[0035] According to a particular embodiment, said first channel and / or said second channel follows a path defining a corrugation in a corrugation plane substantially perpendicular to a main plane of said plate.

[0036] In other words, the plate, and in particular its active surface, that is to say the surface ensuring proton exchange, positioned facing the membrane, is defined in three dimensions and no longer according to a plane. It has defined corrugations or "cavities" and "ridges" to optimize the pressure of the gas and / or the flow rate of the heat transfer fluid.

[0037] According to a particular embodiment, the first channel extends in a direction orthogonal to the direction of the second channel.

[0038] In particular, the channels may extend parallel to the length and width of the respective plate by crossing each other and following the corrugations.

[0039] According to another aspect, which may be implemented independently of the first aspect if desired, the channel has a variable cross section.

[0040] This allows in particular to optimize the pressure of the gas and / or the current density delivered by the plate.

[0041] In particular, the minimum cross section may correspond to a position where a first channel of the first channels intersects a second channel of the second channels.

[0042] The present invention also relates to a fuel cell manufactured according to the above method.

[0043] Some of these cells have a first predetermined power output corresponding to a first membrane specification covering the maximum active surface of the plate.

[0044] Other cells may have a second predetermined power output corresponding to a second membrane specification having a surface area less than the maximum active surface of the plate.

[0045] In particular, these cells may belong to a group comprising membranes having the following characteristics:

[0046] - a second format which covers substantially 75% of said active surface; or

[0047] - a third format which covers substantially 50% of the active surface; or

[0048] - a fourth dimension, which substantially covers 25% of the active surface.

[0049] In particular, when the first channel has a pattern that is repeated at least twice, each of the film formats may cover a different number of patterns. 4. Description of the drawings

[0050] Other characteristics and advantages of the invention will become more apparent from a reading of the following description of exemplary embodiments given as simple illustrative and non-limiting examples, and of the accompanying drawings, in which:

[0051] [ Figure 1 ]: Figure 1 It has been described in the previous text, showing the general principle of a fuel cell;

[0052] [ Figure 2 ]: Figure 2 As has been described above, the structure of a fuel cell including a stack of unit cells is shown;

[0053] [ Figure 3 ]: Figure 3 As described above, the formation is shown in the form of an exploded view. Figure 2 Elements of the battery;

[0054] [ Figure 4 ]: Figure 4 Schematically shows Figure 3 The main elements of the bipolar plates of the unit cells;

[0055] [ Figure 5A ]、[ Figure 5B ]: Figure 5A and Figure 5B The trajectory of the gas (hydrogen or air) flow and the trajectory of the heat transfer fluid are shown respectively, these trajectories follow the corrugations (only a part of the half plate is shown);

[0056] [ Figure 6 ]: Figure 6 is another view of a portion of a half plate showing the corrugations according to two orthogonal directions defined by the channels;

[0057] [ Figure 7 ]: Figure 7 An example of a corrugated portion is schematically shown;

[0058] [ Figure 8 ]: Figure 8 The variation of the cross section of the gas channel is shown.

[0059] [ Fig. 9 ]: Fig. 9 An example of a plate allowing the implementation of the invention is shown;

[0060] [ Fig. 10A ]: Fig. 10A Shows Fig. 9 The first use of a plate where the membrane covers 100% of the active surface;

[0061] [ Fig. 10B ]: Fig. 10B Shows Fig. 9 The first use of a plate where the membrane covers 75% of the active surface;

[0062] [ Fig. 10C ]: Fig. 10C Shows Fig. 9 First use of a plate where the membrane covers 50% of the active surface;

[0063] [ Fig. 10D ]: Fig. 10D Shows Fig. 9 The first use of a plate where the membrane covers 25% of the active surface;

[0064] [ Fig.11 ]: Fig.11 The method of the present invention is presented in schematic form. 5. Specific implementation methods

[0065] 5.1 Method of the Invention

[0066] The invention is therefore based on a truly novel method of designing and manufacturing fuel cells. According to the prior art, a person skilled in the art develops a specific plate design for the required power, in particular the active part of the plate, opposite to which the membrane allowing proton exchange will be placed.

[0067] However, according to the present invention, a single plate is provided and multiple (at least two) membrane sizes can be placed between two plates. Thus, multiple cells with different powers can be easily manufactured based on a single type of plate.

[0068] Therefore, according to a specific embodiment:

[0069] - obtaining a plate having a single rectangular format, the first channel and the second channel of which extend in orthogonal directions (D1, D2) respectively along the length and width of said plate;

[0070] - Obtaining at least two types of membranes corresponding to at least two membrane specifications, each membrane specification is defined by a height and a length, the height being the same for all types of membranes and being selected to cover all of the first channels, and the length being different depending on the type of membrane.

[0071] like Fig. 9 As shown in the example of FIG. 1 , there is a plate 90 shown in a simplified manner and the plate comprises a first channel 91 for conveying reactants and a second channel 92 for conveying a heat transfer fluid, the second channel 92 being orthogonal to the first channel 91. In this figure, the first channel 91 extends horizontally in a direction D1 and the second channel 92 extends orthogonally in a direction D2.

[0072] These channels, and at least the first channel 91, advantageously have a repeating pattern (corrugations and / or cross-sections, as shown below). Thus, the first channels follow the same curve.

[0073] In the first passage along the direction D1 , the pattern may also be repeated, and the zones may be repeated, here in number of 4 zones, to include the full number of patterns.

[0074] Preferably, each pattern allows optimization of the fluid distribution in the channels, and therefore it is desirable that the full number of patterns is used for each type of cell (that is, the membrane covers the full number of patterns).

[0075] Furthermore, regardless of the cell type and the size of the membrane, according to the preferred method of the invention, all available reactants can be used. Thus, advantageously, the membrane covers all reactant channels (that is, it extends over the entire height in direction D2), such as FIG. 10A to FIG. 10D shown.

[0076] The plate 90 can be cut along the direction D1 into four identical or similar parts 901, 902, 903 and 904. Each zone can be optimized in terms of fluid distribution (thereby increasing efficiency in terms of power output production), and multiple types of membranes can be used to cover one or more of the parts:

[0077] - Fig. 10A : Membrane 101 covers all 4 parts (100% of active surface);

[0078] - Fig. 10B : The membrane 102 covers 3 parts (75% of the active surface);

[0079] - Fig. 10C : The membrane 103 covers 2 parts (50% of the active surface);

[0080] - Fig. 10D : The membrane 104 covers 1 single section (25% of the active surface).

[0081] Thus, starting from a single board, four cell power outputs can be obtained, that is, without the need to design a specific board or a specific tool.

[0082] Fig.11 A manufacturing method of the present invention according to one embodiment is shown.

[0083] The plates are manufactured (E1) according to a single size and a single specification. In addition, in this example, membranes with different sizes are manufactured according to three different specifications (E2A, E2B and E2C). Depending on the required power. The plates and the selected membranes (E3A, E3B and E3C) are then assembled to manufacture cells with different power outputs PA, PB or PC.

[0084] This approach goes against the practice of those skilled in the art, who always develop panels and cells for maximum power output, that is to say using 100% of the active surface. It is not obvious to a person skilled in the art to decide to use only a portion of the active surface.

[0085] Of course, the plates used should be as efficient as possible.One of the difficulties in designing fuel cells and in particular the plates is the optimization and homogenization of the trajectory of the coolant, which is usually imposed by the trajectories designed for the gas circulation of the anode part and the gas circulation of the cathode part.

[0086] Specific embodiments of panels suitable for practicing the present invention are described below.

[0087] 5.2 Main Elements of Bipolar Plates

[0088] Different types of channels for the circulation of gases are known, in particular straight channels, channels parallel to one another, serpentine or zigzag channels, channels extending over the active part of the plate.

[0089] The efficiency of these plates is not perfect. Despite the efforts of the designers, significant variations in gas pressure, especially oxygen pressure, at the active surface were observed, as well as inhomogeneous distribution of the heat transfer fluid, especially in the middle of the plate. This can cause thermal inhomogeneities, especially hot spots.

[0090] This, therefore, leads to non-uniformity in the current generation in the plate.

[0091] Furthermore, such plates are also not easy to manufacture and assemble. They have particularly poor rigidity over their length, which results in the use of relatively thick and therefore heavy metal strips, and they require the use of manufacturing techniques such as brazing or multiple welding that are not well suited to mass production.

[0092] Therefore, there is a need for a novel method of manufacturing such panels in order to make the production more adaptable to the requirements of the series and / or to increase its efficiency.

[0093] For ease of explanation, the main aspects of the bipolar plate are described below. Figure 4 As shown schematically in the example of FIG. 1 , there are several basic areas in the bipolar plate:

[0094] - Active zone AZ: This is where the reaction takes place and the active zone AZ consists of many channels. One of the difficulties in the design of these plates is that they must provide a homogeneous gas distribution and not over- or under-gas the channels. The surface of the active zone of the plate is the same as that of the active zone of the MEA;

[0095] - Homogenizing zone HZ: the location where the fluids are mixed, supplying the channels of the active zone with the same amount of gas / coolant. It is similar to a funnel, from the flow inlet to the beginning of the active zone;

[0096] - Anti-bypass zone ABP: the anti-bypass zone is necessary for mechanical reasons such as a well-maintained MEA and / or a good compression joint. Then, the gas bypass effect must be avoided, as this may cause a drop in gas pressure, thus reducing the efficiency of the entire system;

[0097] - Manifolds M: the manifolds are the elements that contribute to the dimensions and include the inlet and outlet for each gas and refrigerant. In general, their location and their dimensions define the overall dimensions of the plate;

[0098] - Inlet I: The inlet is the one that allows gas and refrigerant to enter the gas side or refrigerant side of the plate from the manifold;

[0099] - Guiding interface G: an element that helps keep the unit cells in place during stacking;

[0100] - Measuring electrode V: allows the insertion of a pin or a special device between the anode and cathode for measurement;

[0101] - Data Matrix: allows the precise identification of the board. It can carry in particular the serial number, the supplier's identification number, the time, the date of manufacture, etc. Its dimensions are usually 4×4 mm or 5×5 mm;

[0102] - Poka-yoke: mechanical element that limits the positioning of the half panels;

[0103] -Welds: hold the half plates together, they can be impermeable or serve only to reinforce the structure.

[0104] 5.3 Three-dimensional topology (3D)

[0105] Therefore, according to a specific embodiment, the present invention proposes a new method for a bipolar plate or a monopolar plate, according to which the active area of ​​the bipolar plate or the monopolar plate (i.e., the area substantially facing the membrane) allows the movement of gas and heat transfer fluid in three dimensions of space.

[0106] More precisely, if Figure 5A and Figure 5B As shown, Figure 5A and Figure 5B The paths of the gas (hydrogen or air) flow and the paths of the heat transfer fluid are shown, respectively, the channels 51 intended for the gas and the channels 52 intended for the heat transfer fluid extending in orthogonal directions D1, D2 along the length and width of the plate, respectively, and crossing each other. Moreover, these channels have corrugations in two directions, so that the surface of the active part is not flat, but has "depressions" and "protrusions", as shown in particular in Figure 6 Observed in .

[0107] Compared to the prior art, where the channels extend in the plane defined by the plates, this approach according to embodiments may have a number of advantages:

[0108] - Improved heat convection, allowing for reduced flow rates and / or increased system efficiency;

[0109] - Greater rigidity and / or increased weight of the plate, which allows the thickness of the metal strip to be reduced;

[0110] - Improve electrical contact and reduce electrical contact resistance;

[0111] - facilitate the assembly of the batteries, in particular the alignment of the batteries with respect to one another, thus allowing in particular to avoid sealing problems;

[0112] - Homogenization of oxygen partial pressure along the active surface;

[0113] - Homogenizes the current and increases the current density.

[0114] Figure 7 An example of a corrugation is schematically shown, characterized by the length or period P of the corrugation and the radius R of the corrugation or the maximum height of the corrugation. Of course, the shape of the corrugation may differ from that shown.

[0115] The inventors have taken into account the limitation of the tangent line of the fluid channel and determined that the difference between the radius R and the period P is less than or equal to 20% to be effective, so that the pair (radius; half period) is not too strong and a balance is achieved between too obvious corrugations and too fine corrugations. For example, R = P ± 20%.

[0116] For reference only, the dimensions can be approximately:

[0117] -1 / 2P: between 8mm and 12mm;

[0118] -R: between 16mm and 24mm.

[0119] like Figure 7 As shown, for example, a radius R of 20 mm and a half period of 10 mm can be achieved.

[0120] More generally, the dimensions of a half plate can be approximately:

[0121] - Length: between 250mm and 350mm;

[0122] -Width: between 150mm and 200mm.

[0123] For example, the number of gas channels is between 50 and 100, and the number of heat transfer fluid channels is between 50 and 100.

[0124] 5.4 Channels with variable cross-section

[0125] According to another aspect of the invention, which can be implemented independently of the above-mentioned 3D topology if necessary, the cross section of the channel is varied.

[0126] In fact, the inventors have observed that the active zone according to the prior art, which has a channel for supplying a fluid and has a constant cross section, introduces heat and generates inhomogeneous partial pressures. Furthermore, this has a negative impact on the rigidity of the plate.

[0127] In order to overcome these problems, there are in particular gas channels whose cross-section varies periodically, e.g. Figure 8 As shown, it is observed that along the trajectory 81 of the fluid, the cross section of the channel is at the maximum cross section S max 82 and minimum cross section S min Varies between 83.

[0128] This allows, in particular, to increase the rigidity of the plate, to obtain better heat convection, to balance the voltage divisions and / or to obtain better electrical contact.

[0129] According to one embodiment, the maximum cross-section S max corresponds to the position of the maximum height H of the gas channel 84, and the minimum cross section S min Corresponds to the location where the gas channel 84 intersects (intersects, or "cross channels") with the heat transfer fluid channel 85, where the height reaches a minimum height h.

[0130] The ratio between H and h is preferably between 2 and 3 and is for example such that H=2.5*h.

[0131] By simplification, it is assumed that the width L of the channel does not change much and is constant. Therefore, the cross section S max is equal to approximately L*H, and the cross-sectional area S min Equal to approximately (Hh)*L.

[0132] Therefore, it is preferred to select the cross-sectional variation ratio S max / S min Between 1.5 and 2, for example about 1.6.

[0133] It should be noted that Figure 8 A portion of a half plate is shown, thus showing a half cross section of a channel obtained by assembling two half plates to form a complete plate. But obviously the ratio remains the same.

[0134] For example, just for reference, the dimensions can be approximately:

[0135] -H: between 0.2mm and 0.35mm;

[0136] -h: between 0.1mm and 0.15mm;

[0137] -L: between 0.5mm and 1.3mm.

[0138] The path defining the corrugations and / or the variable cross-section may in particular be defined by a finite element method to maximize one or more criteria, and in particular:

[0139] - Optimizing the fluid distribution in the channel;

[0140] -Optimize the rigidity of each plate;

[0141] - limiting the thickness of a unit cell of a fuel cell consisting of a first bipolar plate, a membrane and a second bipolar plate.

[0142] These paths preferably have a channel pattern that is repeated several times, such as Fig. 9 shown.

[0143] 5.5 Manufacturing and Assembly

[0144] The method of the invention allows the half-plates to be manufactured from finer metal strip than is conventionally used, for example from 316L stainless steel with a double carbon coating of 0.075 mm thickness. This results in less material required to manufacture the battery, which is therefore lighter and less expensive.

[0145] Of course, during the production of the half-plates (e.g. by stamping or molding), special attention needs to be paid to the three-dimensional shape, the presence of half-plates with corrugations in two orthogonal directions (corresponding to the direction of the channels) and / or channels with variable cross-section. A preferred mode of production is hydroforming, which has many advantages, such as precision of process repeatability, elasticity after forming, homogeneity of the thickness of the wall, efficiency of the contact zone, adaptability, etc.

[0146] However, this shape and / or reduced thickness of the metal strip may allow for simpler and more reliable assembly of the two halves forming each plate, in particular for the rigid connection of the half-plates (for example by welding) and for the assembly of the plates to form a battery.

[0147] The invention thus allows to obtain very efficient plates and cells suitable for numerous uses, for example in motor vehicles and more generally in any type of vehicle or device carrying a fuel cell.

Claims

1. A method for manufacturing a plurality of types of fuel cells, said fuel cells delivering different power outputs depending on the type of said cells, said cells comprising a stack of plates, each plate comprising a first channel for circulation of a reactant gas and a second channel for circulation of a heat transfer fluid, said reactant gases being respectively hydrogen and air, a proton exchange membrane being interposed between two adjacent plates, Features: - Get boards of a single specification; - obtaining at least two types of membranes, the at least two types of membranes having at least two membrane specifications, each membrane specification having a different size; - assembling the plate with a membrane of a first one of the membrane specifications to produce a fuel cell of a first type delivering a first power output; - assembling said plate with a membrane of a second one of said membrane specifications to produce a second type of fuel cell delivering a second power output, It is thereby possible to employ the same plates and membranes for each type of cell to obtain multiple types of cells that deliver different power outputs, each cell of a given type of cell implementing a membrane having the same specifications for that type of cell.

2. The method for manufacturing a fuel cell according to claim 1, characterized in that The first channel and the second channel of the plate extend in orthogonal directions (D1, D2) along the length and width of the plate, respectively, and wherein at least two membranes of the type have the same width, thereby covering all of the first channel over a portion of the length of the plate.

3. The method for manufacturing a fuel cell according to any one of claims 1 and 2, characterized in that The first channels all have the same pattern along the direction D1.

4. The method for manufacturing a fuel cell according to any one of claims 1 to 3, characterized in that: The plates are designed to ensure a substantially constant diffusion of the reaction gases and the heat transfer fluid in the zone coinciding with the membrane used, regardless of the surface area of ​​the zone coinciding with the membrane used.

5. The method for manufacturing a fuel cell according to any one of claims 1 to 4, characterized in that: The first channel and / or the second channel follows a path defining a corrugation in a corrugation plane that is substantially perpendicular to a main plane of the plate.

6. The method for manufacturing a fuel cell according to any one of claims 1 to 5, characterized in that: The channel has a maximum cross section (S max ) and minimum cross section (S min ) between the variable cross-sections, the minimum cross-section (S min ) corresponds to the position where a first channel in the first channels intersects a second channel in the second channels.

7. A fuel cell manufactured according to the method of any one of claims 1 to 6.

8. The fuel cell according to claim 7, characterized in that The fuel cell has a first predetermined power output corresponding to a first membrane specification covering a maximum active surface of the plate.

9. The fuel cell according to claim 7, characterized in that: The fuel cell has a second predetermined power output corresponding to a second membrane dimension having a surface area less than the maximum active surface of the plate.

10. The fuel cell according to claim 9, characterized in that The fuel cell belongs to a group comprising a membrane having the following characteristics: - a second format, said second format covering substantially 75% of said active surface; or - a third format, said third format covering substantially 50% of said active surface; or - a fourth dimension, said fourth dimension covering substantially 25% of said active surface.

11. The fuel cell according to any one of claims 7 to 10, characterized in that The first channel has a pattern that is repeated at least twice, and each of the film formats covers a different number of the pattern.

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