JP6277968B2 - Manufacturing method of joined body - Google Patents

Description

  The present invention relates to a technique for manufacturing a joined body.

  A polymer electrolyte fuel cell (hereinafter, also simply referred to as “fuel cell”) includes a membrane electrode assembly as a power generator. The membrane / electrode assembly is an assembly including an electrolyte membrane and catalyst layers disposed on both sides thereof. The electrolyte membrane is composed of a thin film of ion exchange resin. The catalyst layer is configured as a coating film of a dispersion of catalyst-carrying particles (hereinafter also simply referred to as “catalyst ink”).

  Conventionally, as a method for producing a membrane electrode assembly, a method of continuously joining (transferring) electrode members constituting a catalyst layer by hot pressing while transporting a strip-shaped electrolyte membrane along the longitudinal direction is known. ing. Patent Document 1 describes a technique for performing continuous processing by connecting the upper and lower surfaces of a first electrolyte membrane and a second electrolyte membrane with a connecting member in such a manufacturing method.

JP 2014-216108 A JP 2010-225463 A

  The method of forming a catalyst layer by hot pressing requires an electrode member in which a coating film of catalyst ink is formed on a film. Since this film is disposable, according to the method of forming the catalyst layer by hot pressing, there is a problem that the manufacturing cost of the membrane electrode assembly increases. On the other hand, as another method of forming a catalyst layer, a method of directly applying a catalyst ink to an electrolyte membrane is known. According to the method of directly forming the catalyst layer by coating, a film for the electrode member is not required, so that the manufacturing cost of the membrane electrode assembly can be reduced.

  However, in the technique described in Patent Document 1, connection members exist on the upper and lower surfaces of the first electrolyte membrane and the second electrolyte membrane. For this reason, when the method of forming a catalyst layer by direct coating in the technique described in Patent Document 1 is employed, and the first electrolyte membrane and the second electrolyte membrane are continuously treated, the catalyst ink in the electrolyte membrane The connecting member is positioned between the coating surface and the nozzle for applying the catalyst ink. Therefore, the technique described in Patent Document 1 has a problem that the distance between the electrolyte membrane and the coating nozzle cannot be reduced (for example, less than the thickness of the connection member). The technique described in Patent Document 2 does not consider the point of adjusting the distance between the electrolyte membrane and the coating nozzle.

  For this reason, in the manufacturing method of the membrane electrode assembly which connects several electrolyte membranes and performs a continuous process, it was desired to narrow the space | interval between an electrolyte membrane and a coating nozzle. Such a problem is not limited to a method for manufacturing a membrane electrode assembly, and is a common problem in a method for manufacturing a bonded body obtained by laminating membrane members.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

(1) According to one form of this invention, the manufacturing method of a conjugate | zygote is provided. The method of manufacturing the joined body includes: a step of preparing a first laminated body in which films are laminated on the first surface of the electrolyte membrane; and a second laminated body; and an end of the first laminated body; A step of connecting at least a part of the leading end of the second laminated body in the width direction by a connecting member from the film side; the first laminated body and the second laminated body connected to each other; Applying a catalyst material to a second surface opposite to the first surface with respect to the electrolyte membrane to form a catalyst layer.
According to the method for manufacturing a joined body of this embodiment, since the end of the first laminate and the tip of the second laminate are connected by the connecting member, a plurality of electrolyte membranes can be connected and continuously processed. . The connecting member for connecting the first laminate and the second laminate is disposed on the side of the film laminated on the first surface of the electrolyte membrane, and is connected to the second surface of the electrolyte membrane. Is not placed. Therefore, when the catalyst material is continuously applied from the electrolyte film of the first laminate to the electrolyte film of the second laminate, the distance between the second surface of the electrolyte membrane and the application nozzle Can be narrowed (for example, less than the thickness of the connecting member). As a result, in the method for manufacturing a joined body in which a plurality of electrolyte membranes are connected and continuously processed, the interval between the electrolyte membrane and the coating nozzle can be reduced.

(2) In the method for manufacturing a bonded body according to the above aspect, the method further includes a step of disposing a diffusion layer with respect to the formed catalyst layer, wherein the first stacked body and the second stacked body are connected to each other. A step of disposing the diffusion layer across the formed portion; and a step of peeling the film from the connected first laminated body and the second laminated body.
According to the method for manufacturing a bonded body in this aspect, the diffusion layer is disposed across the portion where the first stacked body and the second stacked body are connected, and the first stacked body is disposed after the diffusion layer is disposed. And a film is peeled from a 2nd laminated body. That is, since the electrolyte membrane is held by the catalyst layer and the catalyst layer is held by the diffusion layer, it is possible to suppress co-peeling of the electrolyte membrane during film peeling. Moreover, since the diffusion layer is thicker than the catalyst layer, the tensile strength is high. For this reason, it can suppress that a catalyst layer fractures | ruptures with the force applied at the time of film peeling.

(3) In the method for manufacturing a bonded body according to the above aspect, the first surface appears after peeling of the film with respect to the electrolyte membranes of the connected first laminate and second laminate. And a step of applying a catalyst material to form a catalyst layer; and a step of disposing a diffusion layer on the formed catalyst layer.
According to the method for manufacturing a joined body in this form, when the film is peeled from the first laminated body and the second laminated body, the connecting member is peeled off together with the film. For this reason, the connection member is not arrange | positioned at the 1st surface of the electrolyte membrane which appears after peeling of a film. Therefore, when the catalyst material is continuously applied from the electrolyte membrane of the first laminate to the electrolyte membrane of the second laminate, the distance between the first surface of the electrolyte membrane and the coating nozzle is It can be narrowed (for example, less than the thickness of the connecting member).

(4) In the manufacturing method of the joined body of the above aspect; the connecting step is performed by the connecting member over the entire width direction of the end of the first stacked body and the tip of the second stacked body. You may connect.
According to the method for manufacturing a joined body of this embodiment, the first laminated body and the second laminated body are connected by the connecting member over the entire width direction between the end of the first laminated body and the tip of the second laminated body. 2 laminates can be firmly connected.

  The present invention can be realized in various forms other than the above. For example, a fuel cell manufacturing method, a joined body manufacturing device, a fuel cell manufacturing device, a control method for these devices, a computer program for realizing the control method, and a non-transitory storage medium storing the computer program Can be realized. Moreover, the manufacturing method of the joined body as one aspect of the present invention is to reduce the interval between the electrolyte membrane and the coating nozzle in the manufacturing method of the joined body in which a plurality of electrolyte membranes are connected and continuously processed. It is an issue. However, this manufacturing method also includes a reduction in manufacturing cost, a reduction in the number of manufacturing steps, a simplification of the manufacturing method, a common manufacturing method, resource saving, and a compact manufacturing apparatus for realizing the manufacturing method. Improvement of usability of manufacturing equipment is desired.

It is a flowchart which shows each process performed in the manufacturing method of the membrane electrode assembly as one Embodiment of this invention. It is a figure for demonstrating process P10-process 14 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating process P16 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating process P18 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating process P20 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating process P22 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating process P24 of the manufacturing method of a membrane electrode assembly. It is a figure for demonstrating a comparative example.

A. Embodiment:
FIG. 1 is a flowchart showing each step executed in the method for manufacturing a membrane electrode assembly as one embodiment of the present invention. According to the manufacturing method of this embodiment, a strip-shaped membrane electrode assembly (MEA: Membrane Electrode Assembly) can be manufactured by connecting a plurality of roll-shaped electrolyte membranes and continuously processing them. The strip-shaped membrane electrode assembly is cut into a plurality of sheets in a subsequent process and used for manufacturing a fuel cell.

  FIG. 2 is a diagram for explaining steps P10 to P14 of the method for manufacturing a membrane electrode assembly. In each figure after FIG. 2, the cross section of the electrolyte membrane of the state expand | deployed planarly is illustrated. In step P10, a first stacked body 10a and a second stacked body 10b are prepared. The first laminate 10a is configured by laminating an electrolyte membrane 11a and a film 12a. Similarly, the second laminate 10b is configured by laminating an electrolyte membrane 11b and a film 12b. Hereinafter, when the first stacked body 10a and the second stacked body 10b are described without being distinguished from each other, they are collectively referred to simply as “laminated body 10”. Similarly, when the electrolyte membrane 11a and the electrolyte membrane 11b are described without being distinguished from each other, they are collectively referred to simply as “electrolyte membrane 11”, and when the description is made without distinguishing between the film 12a and the film 12b, both Are also simply referred to as “film 12”.

  The electrolyte membrane 11 is formed of a fluorine-based ion exchange resin. A fluorine-based ion exchange resin exhibits good proton conductivity in a wet state. The thickness L1 of the electrolyte membrane 11 is, for example, about 10 μm. The film 12 is obtained, for example, by applying a fluorine-based or hydrocarbon-based release coating to a polyethylene terephthalate (PET) film. Instead of PET, polypropylene (PP), polyethylene naphthalate (PEN), or the like may be used. Polytetrafluoroethylene (PTFE) and perfluoroalkoxy fluororesin (PFA) can also be used. Hereinafter, of the surfaces of the electrolyte membrane 11, the surface on which the film 12 is laminated (the surface on the lower side in the vertical direction in FIG. 2) is also referred to as “first surface”. Among the surfaces of the electrolyte membrane 11, the surface opposite to the first surface, in other words, the surface on which the film 12 is not laminated (the surface on the upper side in the vertical direction in FIG. 2) is the “second surface”. Also called.

  In step P12, the two stacked bodies 10 are arranged so that the end of the first stacked body 10a and the tip of the second stacked body 10b are adjacent to each other. Under the present circumstances, the two laminated bodies 10 are arrange | positioned in the state which match | combined the vertical relationship of the electrolyte membrane 11 and the film 12. FIG. “Adjusting the vertical relationship” means, for example, when the first laminated body 10a is arranged such that the electrolyte membrane 11a is positioned on the upper side in the vertical direction and the film 12a is positioned on the lower side in the vertical direction. Similarly, the laminated body 10b means an arrangement in which the electrolyte membrane 11b is positioned on the upper side in the vertical direction and the film 12b is positioned on the lower side in the vertical direction. In step P12, an arbitrary interval SP may be provided between the end of the first stacked body 10a and the tip of the second stacked body 10b. The interval SP is preferably as small as possible from the viewpoint of the connection strength of the connection member 50 and the manufacturing cost of the membrane electrode assembly.

  In step P14, the first stacked body 10a disposed in step P12 and the second stacked body 10b are connected. Specifically, at least part of the width direction (the direction perpendicular to the thickness direction and the conveyance direction indicated by arrows in FIG. 2) between the end of the first stacked body 10a and the tip of the second stacked body 10b On the other hand, the connection member 50 is adhered to connect the two. At this time, the connection member 50 is adhered to the film 12 side. The connection member 50 is obtained by using an acrylic adhesive for a polyimide tape, for example. Instead of polyimide, PET, PEN, PP or the like may be used. A thickness L2 of the connection member 50 is, for example, about 35 μm.

  As a result of Steps P10 to P14, the first stacked body 10a and the second stacked body 10b are connected by the connecting member 50 as shown in FIG. For this reason, in the subsequent processes P16 to P24, the first stacked body 10a and the second stacked body 10b can be continuously processed to form the catalyst layer and the diffusion layer.

  FIG. 3 is a view for explaining a process P16 of the method for producing a membrane / electrode assembly. In Step P16, one catalyst layer is formed for the two stacked bodies 10 connected. Specifically, the catalyst ink is applied by the coater 91 to the second surface of the electrolyte membrane 11 of the connected first laminate 10a and second laminate 10b. As the coater 91, for example, a die coder can be used. The catalyst ink is produced, for example, by dispersing a mixture obtained by adding catalyst-carrying particles, water, a hydrophilic catalyst, and an ionomer using an ultrasonic homogenizer or a bead mill. The catalyst ink functions as a “catalyst material”. During the coating process P16, the surface on the film 12 side is supported by a roller 92. After coating the catalyst ink, the coating layer 21c is dried using, for example, a drying furnace (not shown) to form the catalyst layer 21. The thickness L3 of the catalyst layer 21 is, for example, about 3 μm.

  As a result of the process P16, the catalyst layer 21 is formed on the second surface of the electrolyte membrane 11 of the first stacked body 10a and the second stacked body 10b.

  Thus, the connection member 50 for connecting the first laminated body 10a and the second laminated body 10b is disposed on the side of the film 12 laminated on the first surface of the electrolyte membrane 11, and the electrolyte It is not disposed on the second surface of the film 11. Therefore, in the process P16, when the catalyst ink (catalyst material) is continuously applied from the electrolyte film 11a of the first stacked body 10a to the electrolyte film 11b of the second stacked body 10b, The distance CL between the second surface and the coating nozzle of the coater 91 can be narrowed (for example, the thickness L2 or less of the connecting member 50). If the interval CL can be narrowed, the basis weight of the catalyst ink can be reduced, so that a thinner catalyst layer 21 can be formed.

  FIG. 4 is a diagram for explaining a process P18 of the method for manufacturing a membrane / electrode assembly. In step P18, one diffusion layer is formed for the two stacked bodies 10 connected. Specifically, the diffusion layer 31 is disposed with respect to the catalyst layer 21 formed in the process P16. The diffusion layer 31 may be a gas diffusion layer (GDL: Gas Diffusion Layer) or a gas diffusion layer with a microporous layer (MPL). The thickness L4 of the diffusion layer 31 is about 200 μm, for example. After disposing the diffusion layer 31, the laminate 10, the catalyst layer 21, and the diffusion layer 31 are integrated and fed into two hot rollers (not shown) to heat and pressurize the catalyst layer 21 and the diffusion layer 31. Join.

  As a result of the process P18, a diffusion layer 31 is further formed on the catalyst layer 21 formed on the electrolyte membrane 11 of the first stacked body 10a and the second stacked body 10b. As shown in FIG. 4, the diffusion layer 31 is formed so as to straddle the first stacked body 10a and the second stacked body 10b.

  FIG. 5 is a diagram for explaining a process P20 of the method for producing a membrane / electrode assembly. In step P20, the film is peeled off. Specifically, the film 12 is peeled from the end of one of the first laminate 10a and the second laminate 10b that is not connected by the connecting member 50. To do. In the example of FIG. 5, the film 12 is peeled off from the end of the second laminate 10b. Since the 1st laminated body 10a and the 2nd laminated body 10b are connected by the connection member 50, as shown in FIG. 5, the film 12a of the 1st laminated body 10a, and the 2nd laminated body 10b The film 12b is peeled together.

  In this manner, the diffusion layer 31 is disposed across the portion where the first stacked body 10a and the second stacked body 10b are connected. After the diffusion layer 31 is disposed, the first stacked body 10a and the second stacked body 10 The film 12 is peeled from the laminate 10b. At this time, since the electrolyte membrane 11 is held by the catalyst layer 21 and the catalyst layer 21 is held by the diffusion layer 31, the electrolyte membrane 11 is peeled off together with the film 12 when the film 12 is peeled off in the process P20 ( (Co-peeling of the electrolyte membrane 11) can be suppressed. Further, since the thickness L4 (about 200 μm) of the diffusion layer 31 is larger than the thickness L3 (about 3 μm) of the catalyst layer 21, the diffusion layer 31 has a higher tensile strength than the catalyst layer 21. For this reason, it is possible to prevent the catalyst layer 21 from being broken by the force applied when the film 12 is peeled off.

  FIG. 6 is a diagram for explaining a process P22 of the method for manufacturing a membrane electrode assembly. In the process P22, the other catalyst layer is formed with respect to the two laminated bodies 10 connected. Details are the same as in step P16. However, in the process P22, the catalyst ink is applied to the first surface of the electrolyte membrane 11 that appears after the film 12 is peeled out of the connected first laminated body 10a and second laminated body 10b.

  As a result of the process P22, the catalyst layer 22 is formed on the first surface of the electrolyte membrane 11 of the first stacked body 10a and the second stacked body 10b.

  Thus, when the film 12 is peeled from the first laminate 10a and the second laminate 10b, the connection member 50 is peeled together with the film 12. For this reason, the connection member 50 is not disposed on the first surface of the electrolyte membrane 11 that appears after the film 12 is peeled off. Therefore, in the process P22, when the catalyst ink (catalyst material) is continuously applied from the electrolyte membrane 11a of the first laminate 10a to the electrolyte membrane 11b of the second laminate 10b, the first of the electrolyte membrane 11 is applied. The distance CL between the surface 1 and the coating nozzle of the coater 91 can be reduced (for example, the thickness L2 or less of the connecting member 50).

  FIG. 7 is a diagram for explaining a process P24 of the method for manufacturing a membrane / electrode assembly. In Step P24, the other diffusion layer is formed for the two stacked bodies 10 connected. Details are the same as in step P18. However, in the process P24, the diffusion layer 32 is disposed and bonded to the catalyst layer 22 formed in the process P22.

  As a result of the process P24, a diffusion layer 32 is further formed on the catalyst layer 22 formed on the electrolyte membrane 11 of the first laminate 10a and the second laminate 10b, and the strip-shaped membrane electrode assembly 1 is formed. Can be obtained. In the membrane electrode assembly 1, the vicinity of the interval SP between the electrolyte membrane 11 a and the electrolyte membrane 11 b is cut in a subsequent process and is not used for manufacturing a fuel cell. In the present embodiment, for convenience of explanation, the method of manufacturing the membrane electrode assembly 1 by continuously processing the two electrolyte membranes 11 (that is, the first laminated body 10a and the second laminated body 10b) has been described. . However, the membrane electrode assembly 1 can be manufactured by continuously processing two or more arbitrary plural electrolyte membranes 11 by continuously executing the processes P10 to P24.

As described above, according to the present embodiment, a plurality of electrolyte membranes (the electrolyte membrane 11a of the first laminate 10a and the electrolyte membrane 11b of the second laminate 10b) are connected and continuously joined (membrane). In the manufacturing method of the electrode assembly 1), the distance CL between the electrolyte membrane 11 and the coating nozzle can be reduced. For this reason, this embodiment has the following advantages.
-If the number of the electrolyte membranes 11 to be continuously processed is increased, the operation rate in the production of the membrane electrode assembly 1 can be improved accordingly.
-Since the interval CL can be narrowed, the basis weight of the catalyst ink can be reduced.
Since the thickness L3 of the catalyst layer 21 can be further reduced by using a catalyst ink with a low basis weight, the amount of catalyst ink used and the drying load of the catalyst ink can be reduced.

Furthermore, according to this embodiment, the membrane electrode assembly 1 can be manufactured using a method of directly applying a catalyst ink (catalyst material) to the electrolyte membrane 11. For this reason, this embodiment has the following advantages compared with the manufacturing method of the membrane electrode assembly 1 using the method of forming the catalyst layers 21 and 22 by hot pressing.
-Since it is not necessary to prepare the electrode member which formed the coating film of the catalyst ink on the film beforehand, a work constant can be reduced.
-Since the film for electrode members is not required, manufacturing cost can be reduced.

B. Comparative example:
FIG. 8 is a diagram for explaining a comparative example. In the comparative example, a case where the process P16 (formation of the catalyst layer 21) and the process P18 (formation of the diffusion layer 31) in the method of manufacturing the membrane electrode assembly of the above embodiment are omitted will be described. When the film 12 is peeled from the first laminated body 10a and the second laminated body 10b without forming the catalyst layer 21 and the diffusion layer 31, the film 12 and the electrolyte membrane 11 (on the drawing) In the example, the film 12b and the electrolyte membrane 11b) can be peeled off without any problem. However, the film 12 and the electrolyte membrane 11 (the film 12a and the electrolyte membrane 11a in the example in the figure) on the side connected by the connecting member 50 cannot be peeled off, and the electrolyte membrane 11 is peeled off. This is because the electrolyte membrane 11 a and the electrolyte membrane 11 b are not held by the catalyst layer 21 or the diffusion layer 31.

  Similarly, in the case where only the process P18 (formation of the diffusion layer 31) in the method for manufacturing the membrane / electrode assembly of the above embodiment is omitted, the film 12 and the electrolyte membrane 11 (the example in the drawing) on the side connected by the connecting member 50 are similarly used. Then, the film 12a and the electrolyte membrane 11a) cannot be peeled off, and the catalyst layer 21 is broken and the electrolyte membrane 11 is peeled off. This is because the catalyst layer 21 cannot withstand the pulling force of the catalyst layer 21 because the thickness L3 (about 3 μm) of the catalyst layer 21 is very thin.

C. Variations:
The present invention is not limited to the embodiments, examples, and modifications of the present specification, and can be implemented with various configurations without departing from the spirit of the present invention. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in the embodiments described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects described above, replacement or combination can be performed as appropriate. If the technical feature is not described as essential in this specification, it can be deleted as appropriate. For example, the following are exemplified.

  For example, in the process P14, the first stacked body 10a and the first stacked body 10a are bonded to each other over the entire width direction between the end of the first stacked body 10a and the distal end of the second stacked body 10b. Two laminated bodies 10b may be connected. If it carries out like this, a 1st laminated body and a 2nd laminated body can be connected firmly.

  For example, at least some of the processes P18 to P24 may be omitted. Moreover, you may provide the other process with respect to process P10-P24.

DESCRIPTION OF SYMBOLS 1 ... Membrane electrode assembly 10 ... Laminated body 10a ... 1st laminated body 10b ... 2nd laminated body 11, 11a, 11b ... Electrolyte membrane 12, 12a, 12b ... Film 14 ... Process 21 ... Catalyst layer 21c ... Coating Layer 22 ... Catalyst layer 31 ... Diffusion layer 32 ... Diffusion layer 50 ... Connection member 91 ... Coater 92 ... Roller CL ... Spacing SP ... Spacing

Claims (3)

A method for manufacturing a joined body, comprising:
Preparing a first laminate in which films are respectively laminated on the first surface of the electrolyte membrane, and a second laminate;
Connecting at least part of the width direction of the end of the first laminate and the tip of the second laminate by a connecting member from the film side;
A catalyst layer is formed by applying a catalyst material to the second surface opposite to the first surface with respect to the electrolyte membranes of the connected first laminate and second laminate. And a process of
A method for manufacturing a joined body. It is a manufacturing method of the joined object according to claim 1, and further,
A step of disposing a diffusion layer with respect to the formed catalyst layer, the step of disposing the diffusion layer across a portion where the first stacked body and the second stacked body are connected;
Peeling the film from the connected first laminate and the second laminate, and
A method for manufacturing a joined body. It is a manufacturing method of the joined object according to claim 2, and further,
Applying a catalyst material to the first surface that appears after peeling of the film, and forming a catalyst layer on the electrolyte membranes of the connected first laminate and second laminate; and ,
Disposing a diffusion layer with respect to the formed catalyst layer;
A method for manufacturing a joined body.

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