JP2013062031A - Method for manufacturing fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a fuel cell capable or improving productivity and quality of a finished product.SOLUTION: A method for manufacturing a fuel cell 100 comprises: a winding-out step of winding-out a resin film 22 from a feeder 51 in which the resin film 22 is wound; a molding-injection step of forming a first cavity 60 and a second cavity 61 between a surface 22a of the wound-out resin film 22 and a second mold 56, and a third mold 57 and molding-injection a resin material X into the first cavity 60 and the second cavity 61 to mold a seal member 23; a holding step of holding the resin film 22 in which the seal member 23 is formed thereon to a metal plate P forming a separator 20; a cutting step of cutting a part formed of the seal member in the resin film 22 and hold to the metal plate P; and a taking-up step of taking-up an excess part z of the resin film 22 after cutting to a taking-up device 52.

Description

  The present invention relates to a method for manufacturing a fuel cell.

  For example, a polymer electrolyte fuel cell (PEFC) is composed of an electrolyte membrane / electrode structure in which an anode electrode and a cathode electrode are provided on both sides of an electrolyte membrane made of a polymer ion exchange membrane. A power generation cell sandwiched between separators is provided. A solid polymer membrane fuel cell has a plurality of power generation cells stacked, and is used, for example, as an in-vehicle fuel cell stack.

  In this type of fuel cell stack, a flow path for passing a fuel gas (for example, hydrogen) is formed on the surface of the separator facing the anode electrode, while the surface of the separator facing the cathode electrode is formed on the surface of the separator facing the cathode electrode. In addition, a flow path for allowing an oxidant gas (for example, a gas containing oxygen such as air) to flow therethrough is formed. In addition, a flow path for allowing a cooling medium to flow is formed between separators of adjacent power generation cells.

By the way, at the time of power generation of the fuel cell stack, the fuel gas, the oxidant gas, and the cooling medium are flowed into the fuel cell stack through the respective flow paths. Therefore, in order to prevent the fuel gas, the oxidant gas, and the cooling medium from leaking out or mixing to the outside of the fuel cell stack, a seal member is provided around the outer periphery of the both surfaces of the separator and the flow path. ing.
In the past, many methods for forming a seal member on a separator have been developed and put to practical use.

  For example, Patent Document 1 discloses a method of injection molding a seal member on a metal plate constituting a separator. That is, in Patent Document 1, in a state where the metal plate is disposed in one mold, the other mold is brought close to the one mold to perform clamping, and between the other mold and the metal plate A cavity is formed. Subsequently, for example, a molten resin material such as silicone rubber is injected into the cavity, and a seal member is provided on the surface of the metal plate.

JP 2004-223858 A

  However, in the technique of Patent Document 1, it is necessary to arrange the metal plates one by one in the mold every time the resin material is injected into the metal plate, so that the productivity is low.

  Moreover, in the technique of the said patent document 1, due to a dimensional error etc., a gap will inevitably occur on the mating surface (mold splitting surface) between the molds, and a resin material flows into the gap during injection molding. Since the resin material cured in the gap becomes burrs, the quality of the finished product may be deteriorated.

  The present invention has been developed from such a viewpoint, and an object of the present invention is to provide a method of manufacturing a fuel cell in which productivity is improved and quality of a finished product is improved.

  In order to solve the above problems, the present invention is a method of manufacturing a fuel cell comprising an electrolyte / electrode structure having an electrolyte membrane interposed between an anode electrode and a cathode electrode with a pair of separators, A unwinding step of unwinding the resin film from a supply device wound with the resin film, forming a cavity between the surface of the unrolled resin film and a mold, and placing a resin material in the cavity Of the resin film, the sealing member is formed by an injection molding step of injecting and molding a sealing member, a fixing step of fixing the resin film on which the sealing member is molded to a metal plate constituting the separator, and And a cutting step of cutting a portion fixed to the metal plate, and a winding step of winding the surplus portion after cutting of the resin film on a winding device; Characterized in that it comprises a.

  According to the present invention, in the process of sending the resin film from the supply device to the take-up device, the sealing member is formed on the surface of the resin film, the resin film is fixed to the metal plate, the sealing member is formed, and the metal plate is formed. By cutting the fixed resin film, a separator having a sealing member can be continuously manufactured, so that the productivity of the separator is improved.

  Further, according to the present invention, when a cavity is formed between the surface of the resin film and the mold and the resin material is injected into the cavity, the resin film receives a pressing force from the mold at the time of clamping. Since it deforms following the mold shape, the adhesion between the resin film and the mold is enhanced as compared with the adhesion between the molds. As a result, it is difficult for gaps to occur on the mating surface between the resin film and the mold, and as a result, burrs are less likely to occur, so that the quality of the finished product is improved.

  Further, a pair of the supply device and a pair of the winding devices are arranged on both sides of the metal plate, and the resin film on which the seal member is formed is fixed to both the front and back surfaces of the metal plate. It is preferable to configure.

  According to this configuration, since the resin film on which the sealing member is formed can be simultaneously fixed to both the front and back surfaces of the metal plate in the process of sending the resin film from the pair of supply devices to the pair of winding devices, the productivity of the separator Is further improved.

  ADVANTAGE OF THE INVENTION According to this invention, productivity can improve and the manufacturing method of the fuel cell which can improve the quality of a finished product can be provided.

1 is an exploded perspective view of a fuel cell according to an embodiment of the present invention. It is a partial expanded cross-sectional view of a fuel cell. It is explanatory drawing which shows an injection molding process and a fixing process. It is a schematic perspective view which shows the manufacturing process of a separator.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the description, the same elements are denoted by the same reference numerals, and redundant description is omitted.

Prior to the description of the manufacturing method of the fuel cell 100 according to the embodiment of the present invention, the structure of the fuel cell 100 will be described with reference to FIGS.
As shown in FIG. 1, the fuel cell 100 includes an electrolyte membrane / electrode structure (MEA) 10 and a pair of separators 20 and 20 that sandwich the electrolyte membrane / electrode structure 10 from both sides.

<Electrolyte membrane / electrode structure>
The electrolyte membrane / electrode structure 10 includes, for example, a plate-like solid polymer electrolyte membrane (electrolyte membrane) 11 in which a perfluorosulfonic acid thin film is impregnated with water, and both sides (both sides) of the solid polymer electrolyte membrane 11. The cathode electrode 12 and the anode electrode 13 are provided.

  The cathode electrode 12 and the anode electrode 13 are rectangular electrode members having a width dimension and a length dimension that are slightly smaller than the solid polymer electrolyte membrane 11. The cathode electrode 12 and the anode electrode 13 are disposed in the central portion of the solid polymer electrolyte membrane 11, and the outer peripheral portion is located inward of the outer peripheral portion of the solid polymer electrolyte membrane 11. The cathode electrode 12 and the anode electrode 13 are a gas diffusion layer made of carbon paper or the like, and an electrode catalyst layer formed by uniformly applying porous carbon particles carrying a platinum alloy on the surface of the gas diffusion layer. And. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 11.

<Separator>
The separator 20 includes a separator body 21, a resin film 22, and a seal member 23.

<Separator body>
The separator main body 21 is composed of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, a metal plate whose surface is subjected to anticorrosion treatment, and the like. As shown in FIGS. 1 and 2, the separator main body 21 is formed in a concavo-convex shape in cross-sectional view by pressing a rectangular metal plate into a wave shape.

<Resin film>
As shown in FIG. 2, the resin film 22 is a resin member that is fixed (fixed) to both surfaces 21 a and 21 b of the separator body 21 and improves the insulating performance of the separator 20. As shown in FIG. 1, the resin film 22 includes an outer edge portion of the separator body 21, a supply port such as an oxidant gas supply port 30 a described later, a discharge port such as an oxidant gas discharge port 30 b, and an oxidant gas flow path 40. It is provided around the flow path. As will be described later, the resin film 22 is wound around the supply device 51 and the winding device 52 when the separator 20 is manufactured, and the resin material X is injected onto the surface 22a (see FIGS. 3 and 4). It is preferable to use a resin film 22 that has elasticity and does not fuse (weld) to the mold 53 at the mold temperature. That is, it is preferable to use a resin film 22 having a melting point higher than the mold temperature. The resin film 22 of the present embodiment is made of polyethylene terephthalate, which is a thermoplastic resin. However, the present invention is not limited to this. For example, fluororesin such as polytetrafluoroethylene, polyamide, polycarbonate, poly Engineering plastics such as butylene terephthalate, polyamide imide, polyfinylene sulfide, polyether imide, polyethylene naphthalate, polyether ether ketone, super engineering plastics such as liquid crystal polymer, polyethylene, polypropylene and the like may be used.

<Seal member>
As shown in FIG. 2, the seal member 23 is a resin member that is fixed (fixed) to the surface 22 a of the resin film 22. As shown in FIG. 1, the seal member 23 is provided around the outer edge of the separator body 21, a supply port, a discharge port, and a flow path described later. The seal member 23 of the present embodiment is composed of silicone rubber which is a thermosetting resin, but the present invention is not limited to this, and for example, ethylene-propylene rubber, natural rubber, fluororubber, fluorosilicone. It may be composed of rubber, butyl rubber, styrene rubber, chloroplane, acrylic rubber or the like.

<Oxidant gas supply port, cooling medium supply port, fuel gas supply port>
A rectangular oxidant gas supply port 30a and a cooling medium supply port 31a formed through the solid polymer electrolyte membrane 11 and the upper edge portion (one end portion) of the separator body 21 in the direction of arrow A (stacking direction). The fuel gas supply ports 32a are arranged along the arrow B direction. The oxidant gas supply port 30a is a part to which an oxidant gas (for example, air containing oxygen) is supplied, and the cooling medium supply port 31a is a part to which a cooling medium is supplied, and serves as a fuel serving as a gas supply port. The gas supply port 32a is a portion to which a fuel gas (for example, a gas containing hydrogen) is supplied. For example, pure water, ethylene glycol, oil, or the like is used as the cooling medium.

<Oxidant gas outlet, cooling medium outlet, fuel gas outlet>
A rectangular oxidant gas discharge port 30b, a coolant discharge port 31b, and a fuel gas formed in the lower edge portion (the other end portion) of the solid polymer electrolyte membrane 11 and the separator main body 21 so as to penetrate in the arrow A direction. The discharge ports 32b are arranged along the arrow B direction. The oxidant gas outlet 30b is a part from which the oxidant gas is discharged, the cooling medium outlet 31b is a part from which the cooling medium is discharged, and the fuel gas outlet 32b is a part from which the fuel gas is discharged. It is.

<Oxidant gas flow path>
As shown in FIGS. 1 and 2, the surface 20a of the one separator 20 facing the electrolyte membrane / electrode structure 10 is oxidized through an oxidant gas supply port 30a and an oxidant gas discharge port 30b. An oxidant gas flow path 40 for flowing the oxidant gas is provided.

<Fuel gas flow path>
As shown in FIGS. 1 and 2, a fuel gas supply port 32a and a fuel gas discharge port 32b are communicated with a surface 20a of the other separator 20 facing the electrolyte membrane / electrode structure 10 to supply fuel gas. A fuel gas passage 42 for flowing is provided.

<Cooling medium flow path>
As shown in FIGS. 1 and 2, the surface 20b of the other separator 20 is provided with a cooling medium flow path 41 for allowing the cooling medium to flow through the cooling medium supply port 31a and the cooling medium discharge port 31b. ing.

  The fuel cell 100 according to the embodiment of the present invention is basically configured as described above. Next, referring to FIGS. 3 and 4 as appropriate, the fuel cell 100 is manufactured when the fuel cell 100 is manufactured. The device 50 will be described. FIG. 3 is an explanatory view showing an injection molding process and a fixing process, and FIG. 4 is a schematic perspective view showing a separator manufacturing process.

<Manufacturing equipment>
As shown in FIG. 3, the manufacturing apparatus 50 mainly includes a pair of supply devices 51, 51, a pair of winding devices 52, 52, a mold 53, and a press device 54.

<Supply device>
The supply device 51 is a cylindrical roll device in which the resin film 22 is wound and the resin film 22 is supplied to the winding device 52. The supply device 51 is configured to be rotated at a predetermined rotational speed by a driving unit (not shown) (for example, a motor), and to send the resin film 22 toward the winding device 52 at a predetermined speed. The supply devices 51 and 51 are vertically spaced apart from each other by a predetermined distance, and rotate in opposite directions around the horizontal axis.

<Winding device>
The winding device 52 is a cylindrical roll device that is disposed at a predetermined interval in the horizontal direction with respect to the supply device 51 and winds the resin film 22 supplied from the supply device 51. The winding device 52 is configured to be rotated at a predetermined rotational speed by a driving means (for example, a motor) (not shown) and to wind up the resin film 22 at a predetermined speed. The winding devices 52 and 52 are provided at a predetermined interval in the vertical direction and rotate in opposite directions around the horizontal axis.

<Mold>
The mold 53 is a metal member disposed between the supply device 51 and the winding device 52 and close to the supply device 51. The mold 53 is a first mold 55 disposed between the resin films 22 and 22 delivered from the supply devices 51 and 51, and a first mold 55 disposed above the first mold 55 with the resin film 22 interposed therebetween. 2 molds 56 and a third mold 57 disposed below the first mold 55 with the resin film 22 interposed therebetween.

  The second mold 56 and the third mold 57 are moved so as to approach and separate from the first mold 55 along the vertical direction (axial direction) by a driving device of an injection molding machine (not shown). On the bottom surface of the second mold 56, a first cavity surface 56 a that is recessed corresponding to the shape of the seal member 23 is formed. A first cavity 60 is formed between the first cavity surface 56 a and the resin film 22 when the first mold 55 and the second mold 56 are clamped. The second mold 56 is formed with a first gate 56b as a passage for supplying a resin material (molten resin) X from an injection molding machine (not shown) to the first cavity 60. The outlet of the first gate 56 b opens to the first cavity surface 56 a, and the inlet opens to the top surface of the second mold 56.

  A second cavity surface 57 a is formed on the top surface of the third mold 57 so as to be recessed corresponding to the shape of the seal member 23. A second cavity 61 is formed between the second cavity surface 57 a and the resin film 22 when the first mold 55 and the third mold 57 are clamped. The third mold 57 is provided with a second gate 57b as a passage for supplying the resin material X from an injection molding machine (not shown) to the second cavity 61. The outlet of the second gate 57 b opens to the second cavity surface 57 a, and the inlet opens to the bottom surface of the third mold 57.

<Pressing machine>
The press device 54 is a device that is appropriately selected from conventionally known press devices, and presses the resin films 22 and 22 onto the front and back surfaces P1 and P2 of the metal plate P constituting the separator body 21. The press device 54 is disposed between the supply device 51 and the winding device 52 and closer to the winding device 52. The press device 54 includes a first press portion 54 a and a second press portion 54 b that are provided at a predetermined interval in the vertical direction across the resin films 22 and 22. The 1st press part 54a and the 2nd press part 54b are moved so that the resin film 22 may be approached / separated along an up-down direction with the drive device which is not shown in figure.

Next, a manufacturing method of the fuel cell 100 will be described with reference to FIGS.
The manufacturing method of the fuel cell 100 of the present embodiment includes an unwinding step, an injection molding step, a first cutting step, a fixing step, a second cutting step, and a winding step.
In FIG. 4, for convenience of explanation, the lower supply device, winding device, resin film, and the like are omitted.

<Unwinding process>
First, as shown in FIGS. 3 and 4, the resin film 22 is unwound from the supply device 51 by a driving means (not shown) or manually, and the resin film 22 is wound around the outer peripheral surface of the winding device 52 a predetermined number of times.

<Injection molding process>
Subsequently, as shown in FIG. 3, the second mold 56 and the third mold 57 are brought closer to the first mold 55, the first mold 55 and the second mold 56 are clamped, and the upper mold The resin film 22 is sandwiched, and the first mold 55 and the third mold 57 are clamped to sandwich the lower resin film 22.
At this time, the first cavity 60 is formed between the surface 22 a of the upper resin film 22 and the first cavity surface 56 a of the second mold 56. Further, a second cavity 61 is formed between the surface 22 a of the lower resin film 22 and the second cavity surface 57 a of the third mold 57.

Then, the resin material X is injected into the first cavity 60 through the first gate 56b, and the resin material X is injected into the second cavity 61 through the second gate 57b to mold the seal member 23.
That is, in this embodiment, since the silicone rubber that is a thermosetting resin is used as the seal member 23, the heat of the mold 53 is transferred to the resin material X, and the resin material X is cured. As a result, the seal member 23 is formed on the surface 22 a of the resin film 22.
On the other hand, in this embodiment, polyethylene terephthalate that is a thermoplastic resin is used as the resin film 22, and the melting point of the resin film 22 is higher than the mold temperature, so the resin film 22 is fused to the mold 53. Can be suppressed.

After the resin material X is cured (after the sealing member 23 is molded), the second mold 56 and the third mold 57 are separated from the first mold 55, and the first mold 55 and the second mold 56 are molded. The first mold 55 and the third mold 57 are opened.
Thereafter, the supply devices 51 and 51 and the winding devices 52 and 52 are rotated by a driving unit (not shown) to move the resin films 22 and 22 toward the winding devices 52 and 52 by a predetermined distance.

<First cutting step>
Subsequently, as shown in FIG. 4, in the resin film 22, a supply port such as the oxidant gas supply port 30 a, a discharge port such as the oxidant gas discharge port 30 b, and a flow channel such as the oxidant gas flow channel 40. The corresponding part is cut (trimmed) by a cutting means (not shown) and cut off.
Thereafter, the supply devices 51 and 51 and the winding devices 52 and 52 are rotated by a driving unit (not shown) to move the resin films 22 and 22 toward the winding devices 52 and 52 by a predetermined distance.

<Fixing process>
Subsequently, as illustrated in FIG. 3, the resin films 22 and 22 on which the seal member 23 is formed are fixed to the front and back surfaces P <b> 1 and P <b> 2 of the metal plate P constituting the separator body 21 by the press device 54.
Specifically, the metal plate P is disposed between the resin films 22 and 22, and the first press portion 54 a and the second press portion 54 b are brought close to the resin films 22 and 22.
At this time, as shown in FIG. 4, the metal plate P is disposed at a position where the cut portion Y of the resin film 22 and the oxidant gas supply port 30 a of the metal plate P correspond vertically.
In addition, the metal plate P is preheated to a temperature equal to or higher than the melting point of the resin film 22 before the metal plate P is arranged. Thereby, the heat of the metal plate P is transferred to the resin film 22 at the time of pressing, and the resin film 22 is melted. As a result, since the resin film 22 is fused to the metal plate P, the resin film 22 can be suitably held on the metal plate P.

Then, the resin films 22 and 22 are pressed (pressed) on the metal plate P from both the upper and lower sides by the first press portion 54a and the second press portion 54b. Thereby, the resin films 22 and 22 are pressure-bonded (thermally welded) to the front and back surfaces P1 and P2 of the metal plate P. After the pressure bonding of the resin films 22 and 22, the first press portion 54 a and the second press portion 54 b are separated from the resin films 22 and 22.
Thereafter, the supply devices 51 and 51 and the winding devices 52 and 52 are rotated by a driving unit (not shown), and the resin films 22 and 22 pressed against the metal plate P are moved to the winding devices 52 and 52 side together with the metal plate P. Move it a predetermined distance.

<Second cutting step>
Subsequently, as shown in FIG. 4, a portion of the resin film 22 where the sealing member 23 is molded and fixed to the metal plate P is cut and cut by a cutting means (not shown). The separator 20 is completed through the above steps.

<Winding process>
Subsequently, the supply devices 51 and 51 and the winding devices 52 and 52 are rotated, and the resin films 22 and 22 are sent to the winding devices 52 and 52 side. Is wound around the winding devices 52, 52 (see FIGS. 3 and 4).

According to this embodiment described above, in the process of sending the resin film 22 from the supply device 51 to the winding device 52, the manufacturing operation is performed in the order of injection molding process → first cutting process → fixing process → second cutting process. Thereby, since the separator 20 having the seal member 23 can be continuously manufactured, the productivity of the separator 20 is improved.
In particular, a pair of supply devices 51, 51 and a pair of winding devices 52, 52 are arranged on both sides of the resin films 22, 22, respectively, and the resin films 22, 22 in which the sealing members 23, 23 are formed, Since it can fix to the front and back both surfaces P1, P2 of the metal plate P at the same time, the productivity of the separator 20 is further improved.

  Further, a first cavity 60 and a second cavity 61 are formed between the second mold 56 and the third mold 57 and the surface 22 a of the resin film 22, and the first cavity 60 and the second cavity 61 are formed in the first cavity 60 and the second cavity 61. By injecting the resin material X, when the resin film 22 receives a pressing force from the mold 53 during mold clamping, the resin film 22 deforms following the mold shape. The adhesion between the mold 56 and the third mold 57 and the resin film 22 is enhanced. As a result, it is difficult for gaps to occur on the mating surfaces of the second mold 56 and the third mold 57 and the resin film 22, and as a result, burrs are less likely to occur, thereby improving the quality of the finished product.

  In addition, since the mold 53 and the resin film 22 come into contact with each other when the mold is clamped, it is possible to reduce the wear of the mold 53 as compared with a structure in which the molds are in contact with each other. (Service life) is improved.

  As mentioned above, although embodiment of this invention was described in detail with reference to drawings, this invention is not limited to this, In the range which does not deviate from the main point of invention, it can change suitably.

  In the present embodiment, the manufacturing apparatus 50 includes a pair of supply devices 51, 51 and a winding device 52, 52, and simultaneously injects the resin material X onto the pair of resin films 22, 22, and both the front and back surfaces of the metal plate P The resin films 22 and 22 are simultaneously fixed to P1 and P2, but the present invention is not limited to this, and the resin material X is injected into the single resin film 22 and the metal plates P are alternately disposed on each side. The resin film 22 may be fixed. For example, the manufacturing apparatus 50 includes a single supply device 51 and a winding device 52, injects the resin material X onto the single resin film 22, and the resin film 22 on the front surface P <b> 1 (back surface P <b> 2) of the metal plate P. After fixing the resin material X, the resin material X may be injected onto the single resin film 22, and the resin film 22 may be fixed to the back surface P2 (front surface P1) of the metal plate P.

  Moreover, in this embodiment, although the resin film 22 was fixed to the metal plate P by heat welding, this invention is not limited to this, For example, apply | coats adhesive agents, such as a hot-melt-adhesive, to the resin film 22. The resin film 22 may be fixed to the metal plate P with an adhesive. In this case, it is possible to suppress the adhesive from adhering to the mold 53 by using an adhesive having a softening point higher than the mold temperature. In addition, by preheating the metal plate P to a temperature equal to or higher than the softening point of the adhesive before the metal plate P is arranged, the adhesive can be softened and the resin film 22 can be suitably held on the metal plate P.

  Moreover, in this embodiment, the supply direction of the resin film 22 was made to correspond to a horizontal direction, and the separator 20 was manufactured, but this invention is not limited to this, The supply direction of the resin film 22 is made to correspond to a perpendicular direction. The separator 20 may be manufactured.

100 Fuel Cell 10 Electrolyte Membrane / Electrode Structure 11 Solid Polymer Electrolyte Membrane (Electrolyte Membrane)
DESCRIPTION OF SYMBOLS 12 Cathode electrode 13 Anode electrode 20 Separator 21 Separator main body 22 Resin film 22a Surface 23 Seal member 50 Manufacturing apparatus 51 Supply apparatus 52 Winding apparatus 53 Mold 55 1st mold 56 2nd mold 56a 1st cavity surface 56b 1st Gate 57 Third mold 57a Second cavity surface 57b Second gate 60 First cavity 61 Second cavity 54 Press device P Metal plate P1 Front surface P2 Back surface X Resin material

Claims (2)

A method for producing a fuel cell comprising an electrolyte / electrode structure having an electrolyte membrane interposed between an anode electrode and a cathode electrode, sandwiched between a pair of separators,
An unwinding step of unwinding the resin film from a supply device wound with the resin film;
An injection molding step of forming a cavity between the surface of the unrolled resin film and a mold, and injecting a resin material into the cavity to form a seal member;
A fixing step of fixing the resin film formed with the seal member to a metal plate constituting the separator;
Of the resin film, the cutting step in which the sealing member is molded and the portion fixed to the metal plate is cut;
Of the resin film, a winding step of winding a surplus portion after cutting onto a winding device;
A method of manufacturing a fuel cell comprising:   A pair of the supply device and a pair of the winding devices are respectively arranged on both sides of the metal plate, and the resin film on which the seal member is formed is fixed to both front and back surfaces of the metal plate. The method for producing a fuel cell according to claim 1.

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