JP2016091980A - Method for manufacturing membrane-electrode assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a membrane-electrode assembly, by which the peeling from an interface other than a desired interface can be prevented.SOLUTION: A method for manufacturing a membrane-electrode assembly comprises the steps of: stacking a back sheet layer 10, an electrolyte film layer 20, a catalyst layer 30, and a diffusion layer 40 in this order and bonding them together with the electrolyte film layer 20 and the diffusion layer 40 partially adhering to each other; and peeling the back sheet layer 10 from the electrolyte film layer 20 after the stacking and bonding. Thus, it becomes possible to peel off only the back sheet layer 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a membrane electrode assembly (MEA) of a fuel cell.

  The main part of the fuel cell is a membrane electrode assembly in which an electrolyte membrane, a catalyst layer, and a diffusion layer are laminated and joined. In the mass production process of the membrane / electrode assembly, in the process of joining the electrolyte membrane with the auxiliary sheet on which the catalyst layer is formed and the diffusion layer, the auxiliary sheet is peeled after the joining.

  As a technique related to the manufacture of a membrane electrode assembly, for example, after the catalyst layer is transferred to the electrolyte membrane, a peeling step of peeling the base material sheet (auxiliary sheet) while heating the electrolyte membrane and the catalyst layer transfer sheet And a step of bonding a gas diffusion layer on the catalyst layer, a method for producing a membrane electrode assembly is disclosed (see Patent Document 1).

JP, 2014-60167, A

  By the way, in the manufacturing method of the membrane electrode assembly of patent document 1, the diffusion layer is joined after peeling the auxiliary sheet while heating the electrolyte membrane and the catalyst layer transfer sheet.

  However, after the one-layer catalyst layer and the diffusion layer are sequentially laminated and bonded to the electrolyte membrane with the auxiliary sheet, the auxiliary sheet is peeled off from the interface between the catalyst layer and the diffusion layer. That is, since the adhesive force between the catalyst layer and the diffusion layer is weak, it is not possible to peel only the auxiliary sheet from the membrane electrode assembly.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a membrane electrode assembly that prevents peeling from an interface other than a desired interface.

  In order to achieve the above object, a method of manufacturing a membrane electrode assembly according to the present invention includes a backsheet layer, an electrolyte membrane layer, a catalyst layer, and a diffusion layer, which are laminated in this order, and the electrolyte membrane layer and the diffusion layer. Are laminated and bonded, and the backsheet layer is peeled off from the electrolyte membrane layer after the lamination.

  According to the present invention, the adhesion between the electrolyte membrane and the diffusion layer is enhanced by the region where the electrolyte membrane and the diffusion layer are in close contact. Therefore, when the backsheet layer is peeled from the electrolyte membrane layer, the electrolyte membrane layer to the diffusion layer It can suppress that it peels in either interface between, and can peel only a back seat | sheet layer.

In the manufacturing method of the laminated body (membrane electrode assembly) of embodiment of this invention, it is a schematic diagram of the bottom view and side view of an electrolyte membrane layer. It is explanatory drawing of the adhesive force between a catalyst layer-diffusion layer, an electrolyte membrane layer-diffusion layer, and an electrolyte membrane-auxiliary sheet. In other embodiment, it is a schematic diagram of the bottom view and side view of an electrolyte membrane layer. In the lamination process of the laminated body of a comparison form, it is a schematic diagram of the bottom view and the side view of an electrolyte membrane.

  Embodiments of the present invention will be described below. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  First, with reference to FIG. 1, the structure of the laminated body (membrane electrode assembly) 100 which concerns on embodiment of this invention is demonstrated. FIG. 1 is a schematic diagram of a bottom view and a side view of an electrolyte membrane in a stacking process of a laminate according to an embodiment of the present invention.

  As shown in FIG. 1, the laminate 100 according to the present embodiment includes a plurality of layers of at least four layers, and includes a first layer 10, a second layer 20, a third layer 30, and a fourth layer. The layers 40 are sequentially laminated and joined. As the laminated body 100 which concerns on this Embodiment, the membrane electrode assembly (MEA) of a fuel cell is mentioned, for example. In the present embodiment, the first layer 10 corresponds to a backsheet layer (auxiliary sheet), the second layer 20 corresponds to an electrolyte membrane layer, the third layer 30 corresponds to a catalyst layer, and the fourth layer 40 corresponds to a diffusion layer. To do. The plurality of layers 10, 20, 30, and 40 are sequentially laminated and bonded, and the first layer (back sheet layer) 10 is peeled off from the second layer (electrolyte film layer) 20 after bonding.

  In the laminate 100 according to the present embodiment, the adhesion between the third layer (catalyst layer) 30 and the fourth layer (diffusion layer) 40 is the same as that between the second layer (electrolyte membrane layer) 20 and the fourth layer. It has a property smaller than the adhesive force with the layer (diffusion layer) 40 (see FIG. 2).

  As shown in FIGS. 1A and 1B, at least part of the laminate 100 according to the present embodiment includes a second layer (electrolyte film layer) 20 and a fourth layer (diffusion layer) 40. Is provided with a region 21 in close contact with each other. Specifically, when the third layer (catalyst layer) 30 is laminated below the second layer (electrolyte membrane layer) 20, the third layer (catalyst layer) 30 to the second layer (electrolyte membrane layer) ) The third layer (catalyst layer) 30 is laminated so that a part of 20 is exposed. Since the fourth layer (diffusion layer) 40 is laminated below the third layer (catalyst layer) 30 (see FIG. 1C), the exposed portion of the second layer (electrolyte membrane layer) 20 The second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 are in close contact with each other.

  The manufacturing method of the laminated body (membrane electrode assembly) 100 according to the present embodiment is performed using, for example, a roll-to-roll apparatus 1. The region 21 where the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 are in close contact, that is, the exposed portion of the second layer (electrolyte membrane layer) 20 is the transport direction of the laminate 100. Preferably, it is formed at the tip of F.

  Next, with reference to FIG. 1, FIG. 2, and FIG. 4, the operation of the multilayer body (membrane electrode assembly) 100 according to the embodiment of the present invention will be described. As shown in FIG. 1C, the method for manufacturing the laminate 100 according to the present embodiment is performed using a roll-to-roll apparatus 1. The second layer (electrolyte membrane layer) 20 is a very thin film of 10 μm by itself. When the second layer (electrolyte membrane layer) 20 is delivered, the first layer (back sheet layer) 10 having an appropriate adhesion is superposed on the upper surface regardless of whether it is a single wafer type or a roll type. Has been. Since the second layer (electrolyte membrane layer) 20 tends to generate wrinkles, it is necessary to pay close attention to handling during the stacking process of the stacked body 100. Causes of wrinkles include dimensional changes due to humidity expansion and contraction and stretching due to inter-roll tension.

  Therefore, it is preferable to apply some reinforcement to the second layer (electrolyte membrane layer) 20 even during the stacking process of the stacked body 100. However, the installation of a new backsheet layer leads to an increase in cost and the problem of adhesion remains. Accordingly, the first layer (back sheet layer) 10 originally attached when the second layer (electrolyte membrane layer) 20 is delivered is used as it is, and the third layer (catalyst layer) 30 and the fourth layer ( (Diffusion layer of one electrode) 40 is laminated.

  That is, the third layer (catalyst layer) 30 is laminated below the second layer (electrolyte membrane layer) 20 with the first layer (backsheet layer) 10. When the third layer (catalyst layer) 30 is laminated below the second layer (electrolyte film layer) 20, a part of the second layer (electrolyte film layer) 20 from the third layer (catalyst layer) 30. And exposed. The exposed portion of the second layer (electrolyte membrane layer) 20 becomes a region 21 where the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 are in close contact.

  Further, a fourth layer (diffusion layer) 40 is laminated below the third layer (catalyst layer) 30. The first layer (back sheet layer) 10, the second layer (electrolyte membrane layer) 20, the third layer (catalyst layer) 30, and the fourth layer (unipolar diffusion layer) 40 have three pairs. The press rolls 61a, 61b, 62a, 62b, 63a, 63b are pressed and joined while passing. In the region 21 in close contact, the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 are in close contact.

  And in the lamination process of the laminated body 100 which concerns on this Embodiment, the 3rd layer (catalyst layer) 30 is added to the 2nd layer (electrolyte membrane layer) 20 with the 1st layer (back sheet layer) 10, Then, the fourth layer (diffusion layer) 40 is sequentially laminated and bonded, and then the first layer (backsheet layer) 10 is peeled off.

  Here, FIG. 2 is an explanatory view of the adhesion force between the catalyst layer-diffusion layer, the electrolyte membrane layer-diffusion layer, and the electrolyte membrane layer-backsheet layer. In FIG. 2, A is the adhesive force between the second layer (electrolyte membrane layer) 20 and the first layer (backsheet layer) 10. In order to peel only the first layer (backsheet layer) 10, other layers than the adhesion A between the second layer (electrolyte membrane layer) 20 and the first layer (backsheet layer) 10 It is necessary that the adhesive strength of is large. The adhesion between the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 is the adhesion between the second layer (electrolyte membrane) 20 and the first layer (backsheet layer) 10. Greater than A.

  According to the method for manufacturing laminate 100 according to the present embodiment, second region (electrolyte layer) is formed by region 21 where second layer (electrolyte membrane layer) 20 and fourth layer (diffusion layer) 40 are in close contact. The adhesion between the (film layer) 20 and the fourth layer (diffusion layer) 40 is increased. Further, the region 21 to be in close contact exists at the front end of the laminate 100 in the transport direction F as shown in FIG. Therefore, when the first layer (backsheet layer) 10 is peeled from the second layer (electrolyte membrane layer) 20, the second layer (electrolyte membrane layer) 20 to the fourth layer (unipolar diffusion layer). It can suppress peeling between 40, and can peel only the said 1st layer (back sheet layer) 10 from a front-end | tip part favorably.

  Next, in order to confirm the effect of the laminated body 100 according to the present embodiment, as a comparative form, a second layer (electrolyte film layer) 20 and a fourth layer (unipolar diffusion layer) 40 are provided. The stacked body 300 that does not have a close-contact region will be described. FIG. 4 is a schematic view of the electrolyte membrane layer in a side view and a bottom view in the stacking process of the laminate of the comparative form.

  As shown in FIG. 4, in the laminate 300 of the comparative form, the third layer (catalyst layer) 30 is formed on the entire lower surface of the second layer (electrolyte membrane layer) 20. Therefore, the laminated body 300 of the comparative form does not have a region where the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40 are in close contact.

  The adhesion between the third layer (catalyst layer) 30 and the fourth layer (unipolar diffusion layer) 40 is the same as that of the second layer (electrolyte membrane layer) 20 and the fourth layer (unipolar diffusion layer). It has a property smaller than the adhesive strength with 40 (see FIG. 2). Accordingly, the third layer (catalyst layer) 30 and the fourth layer (diffusion layer) 40 are sequentially laminated and joined to the second layer (electrolyte membrane layer) 20 with the first layer (backsheet layer) 10. Thereafter, when the first layer (backsheet layer) 10 is to be peeled off, the adhesion between the third layer (catalyst layer) 30 and the fourth layer (diffusion layer) 40 is weak. The catalyst layer 30 is peeled off from the interface between the fourth layer (diffusion layer) 40 and only the first layer (backsheet layer) 10 cannot be peeled off.

As described above, according to the method for manufacturing the laminate (membrane electrode assembly) 100 according to the present embodiment, the second layer (electrolyte membrane layer) 20, the fourth layer (diffusion layer) 40, By providing the area | region 21 which adheres, the adhesive force of the 4th layer (diffusion layer) 40 from the 2nd layer (electrolyte membrane layer) 20 increases. Therefore, when the first layer (backsheet layer) 10 is peeled from the second layer (electrolyte membrane layer) 20, between the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) 40. Can be suppressed, and only the first layer (backsheet layer) 10 can be peeled off. That is, according to the present embodiment, in the step of laminating a membrane electrode assembly (MEA), after the single electrode catalyst layer and the diffusion layer are sequentially laminated and joined to the electrolyte membrane layer with the backsheet layer, the backsheet layer It has an excellent effect that it can be peeled off only.
[Other Embodiments]

  Although the present invention has been described by the embodiments as described above, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques should be apparent to those skilled in the art.

  FIG. 3 is a schematic view of the electrolyte membrane layer in a bottom view and a side view in another embodiment of the present invention. For example, in the manufacturing method of the laminate (membrane electrode assembly) 100 according to the above-described embodiment, the second layer (electrolyte membrane layer) 20 and the fourth layer ( Although the region 21 in close contact with the (diffusion layer) 40 is formed (see FIG. 1), it may be configured as shown in FIG. As shown in FIG. 3, the second layer (electrolyte membrane layer) 20 and the fourth layer (diffusion layer) are exposed by exposing an intermediate portion in the transport direction F of the second layer (electrolyte membrane layer) 20. You may form the area | region 21 which closely_contact | adheres.

  According to the method for manufacturing a laminated body (membrane electrode assembly) according to another embodiment, when the first layer (back sheet layer) 10 is peeled off, the third layer (catalyst layer) is partway through the laminated body. ) 30 and peeled off at the interface between the fourth layer (diffusion layer). However, when reaching the region 21 where the second layer (electrolyte film layer) 20 and the fourth layer (diffusion layer) in the middle part of the laminate are in close contact, the second layer (electrolyte film layer) 20 and the second layer (electrolyte film layer) 20 Only the first layer (back sheet layer) can be peeled off by the adhesive force with the fourth layer (diffusion layer). Thus, it should be understood that the present invention includes various embodiments and the like not described herein.

  In the above embodiment, the roll-to-roll device has been exemplified and described as the device form. However, the device form is not limited to the roll-to-roll device. You may employ | adopt the apparatus form cut | judged after joining.

10 1st layer (back sheet layer)
20 Second layer (electrolyte membrane layer)
21 Adhering region 30 Third layer (catalyst layer)
40 Fourth layer (diffusion layer)
100 laminate (membrane electrode assembly)

Claims (1)

A method for producing a membrane electrode assembly, comprising:
While laminating in order of the backsheet layer, electrolyte membrane layer, catalyst layer, and diffusion layer, laminating and joining the electrolyte membrane layer and the diffusion layer partially bonded,
A method for producing a membrane / electrode assembly, comprising: peeling off the backsheet layer from the electrolyte membrane layer after the lamination joining.

Images