Method for manufacturing fuel cell, and fuel cell

Abstract

Provided are a method for manufacturing a fuel cell having high bonding strength between a separator and a sealing member, and a fuel cell. In a method for manufacturing a fuel cell according to the present disclosure, the fuel cell is provided with: a laminate including a membrane electrode assembly and a pair of separators that sandwich the membrane electrode assembly; and a sealing part that is provided so as to form a sealed space with respect to a gap formed between adjacent laminates in the lamination direction by laminating the plurality of laminates with a predetermined interval therebetween. In the manufacturing method, a resin layer provided between a spacer and a sealing member is melted, and the spacer and the sealing member are bonded to form a sealing portion.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a fuel cell and a fuel cell. Background Art

[0002] Fuel cells are supplied with fuel gas for power generation and with cooling water for removing heat generated by power generation. Sealing members have been developed to prevent fuel gas and cooling water from leaking to the outside of the fuel cell.

[0003] For example, Japanese Patent Publication No. 2016-018703 discloses a sealing component for preventing fuel gas from leaking out of a fuel cell. The sealing component disclosed in Patent Document 1 is integrated by laminating an adhesive layer on the surface of a sealing component main part made of foam rubber. The sealing component disclosed in Japanese Patent Publication No. 2016-018703 is arranged on a spacer in a manner that it is in close contact with the spacer. Summary of the invention

[0004] In the sealing member disclosed in Japanese Patent Application Laid-Open No. 2016-018703, the sealing member is merely cross-linked and bonded to the spacer, and the bonding strength between the spacer and the sealing member is insufficient.

[0005] The present disclosure has been made in view of such circumstances, and provides a method for manufacturing a fuel cell and a fuel cell in which the bonding strength between a separator and a sealing member is high.

[0006] The present disclosure relates to a method for manufacturing a fuel cell, wherein the fuel cell comprises: a laminate including a membrane electrode assembly and a pair of separators sandwiching the membrane electrode assembly; and a sealing portion provided so as to form a sealed space with respect to a gap formed between the stacked bodies adjacent to each other in the stacking direction by stacking the plurality of stacked bodies at predetermined intervals, In this manufacturing method, the resin layer provided between the spacer and the sealing member is melted to bond the spacer and the sealing member, thereby forming the sealing portion.

[0007] In the method for manufacturing a fuel cell according to the present disclosure, the resin layer is melted and then solidified, thereby bonding the spacer and the sealing member to form a sealing portion. Therefore, a fuel cell having a high bonding strength between the spacer and the sealing member can be manufactured.

[0008] In addition, the resin layer may be arranged between the spacer and the sealing member, and at least both the sealing member and the resin layer may be heated to thereby The resin layer is melted while the sealing member is cross-linked, thereby bonding the spacer and the sealing member. According to such a configuration, the sealing member is heated and cross-linked, thereby solidifying. In addition, the resin layer is heated and melted and then cooled and solidified, so that the spacer and the sealing member are bonded to form a sealing portion. Therefore, a fuel cell with a high bonding strength between the spacer and the sealing member can be manufactured.

[0009] Furthermore, after the sealing member is cross-linked, the resin layer is disposed at a position in contact with the sealing member, and the resin layer is heated to melt the resin layer, thereby bonding the spacer and the sealing member. According to this structure, the crosslinked and solidified sealing member is arranged in contact with the resin layer, and the resin layer is heated to melt and then cooled to solidify, so that the spacer and the sealing member are bonded to form a sealing portion. Therefore, a fuel cell with high bonding strength between the spacer and the sealing member can be manufactured.

[0010] Alternatively, the spacer having the resin layer temporarily bonded to the surface thereof may be disposed in a mold for molding the sealing portion. The sealing member is injected into and filled in the mold, thereby providing the resin layer between the spacer and the sealing member. According to such a configuration, the sealing member is filled so as to cover the spacer having the resin layer temporarily bonded to the surface thereof, and therefore the resin layer can be arranged between the spacer and the sealing member.

[0011] The fuel cell according to the present disclosure is a fuel cell in which a plurality of stacked bodies including a membrane electrode assembly and a pair of separators sandwiching the membrane electrode assembly are stacked at predetermined intervals. The sealing portion provided so as to form a sealed space with respect to a gap formed between the stacked bodies adjacent to each other in the stacking direction of the stacked bodies includes a resin layer between the spacer and the sealing member of the stacked body.

[0012] The fuel cell of the present disclosure has a resin layer disposed between the spacer and the sealing member of the stack, thereby suppressing the unevenness of the bonding strength at the interface between the spacer and the sealing member, and providing a fuel cell with high bonding strength between the spacer and the sealing member.

[0013] According to the present disclosure, it is possible to provide a method for manufacturing a fuel cell and a fuel cell in which the bonding strength between a spacer and a sealing member is high. The above and other objects, features and advantages of the present disclosure will be more fully understood from the detailed description and accompanying drawings given below, which are given as examples only and thus should not be considered as limiting the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a perspective view of the fuel cell according to Embodiment 1. Figure 2 It is a cross-sectional view (xz plane view) of the fuel cell according to the first embodiment. Figure 3 It is a cross-sectional view (yz plane view) of the fuel cell according to the first embodiment. Figure 4 This is a cross-sectional view of a sealing portion of the fuel cell according to Embodiment 1. Figure 5 This is a schematic diagram showing an example of a method for manufacturing a fuel cell according to Embodiment 1. Figure 6 This is a schematic diagram showing an example of a method for manufacturing a fuel cell according to Embodiment 1. DETAILED DESCRIPTION

[0015] Hereinafter, the present invention will be described by the embodiments of the invention, but the invention involved in the claims is not limited to the following embodiments. In addition, not all of the structures described in the embodiments are necessary as means for solving the problems. In order to make the description clear, the following records and drawings are appropriately omitted and simplified. In each of the drawings, the same element is marked with the same figure mark, and repeated descriptions are omitted as needed. In addition, of course, the right-handed xyz orthogonal coordinates shown in the drawings are for the convenience of describing the positional relationship of the constituent elements. Usually, the positive direction of the z-axis is vertically upward, and the xy plane is a horizontal plane.

[0016] (Implementation Method 1) <Composition of fuel cell> First, refer to Figure 1 to Figure 3 , the structure of the fuel cell is explained. Figure 1 This is a perspective view of the fuel cell according to Embodiment 1. Figure 2 It is a cross-sectional view (xz plane view) of the fuel cell according to the first embodiment. Figure 3 It is a cross-sectional view (yz plane view) of the fuel cell according to the first embodiment. Figure 1 to Figure 3 Only the portion of the fuel cell related to power generation is shown, and components such as the restraining plate are omitted.

[0017] Figure 2 The above paragraph shows that Figure 1 A cross-sectional view of the manifold hole 20. Figure 2 The middle section shows the Figure 1 A cross-sectional view of the manifold hole 21. Figure 2 The lower section of FIG. 1 shows a cross-sectional view through the manifold hole 22. Figure 3 In FIG. 1 , a cross-sectional portion between adjacent stacked bodies is shown, and the configuration of the stacked body other than the spacer is omitted and indicated by a dotted line.

[0018] like Figure 1As shown, in the fuel cell 10, a plurality of stacked bodies 11 are stacked at predetermined intervals. Figure 1 In the example shown, three stacks 11 are stacked in the z-axis direction in the fuel cell 10. Hereinafter, the z-axis direction of the drawing is referred to as the stacking direction. Figure 2 , Figure 3 , a state in which two stacked bodies 11 are stacked is shown.

[0019] Reference Figure 2 , Figure 3 , the laminate 11 is described. Figure 2 , Figure 3 As shown, the stack 11 is composed of a membrane electrode assembly 13 and a pair of spacers 14 sandwiching the membrane electrode assembly 13. The membrane electrode assembly 13 has a polymer electrolyte membrane (not shown), and a cathode electrode (not shown) and an anode electrode (not shown) arranged on both sides sandwiching the polymer electrolyte membrane. The spacer 14 is a member formed of a conductive material such as a metal, a carbon material, or a conductive resin material.

[0020] like Figure 2 As shown in the upper part of FIG. 1 , in the stacked body 11, a space SP1 is provided between the membrane electrode assembly 13 and one of the spacers 14. Figure 2 As shown in the lower part of FIG. 1 , in the stacked body 11, a space SP3 is provided between the membrane electrode assembly 13 and the other spacer 14. Figure 3 As shown, a gap is formed between the stacked bodies 11 adjacent in the stacking direction. The sealing portion 12 is provided in the gap. That is, the sealing portion 12 is provided so as to form a closed space CS with respect to the gap formed between the stacked bodies 11 adjacent in the stacking direction.

[0021] Next, refer to Figure 1 to Figure 3 , the flow paths of hydrogen, oxygen, and cooling water supplied to the fuel cell are described. Figure 2 , Figure 3 In the figure, arrows are used to show the directions of flow of hydrogen, oxygen, and cooling water. Figure 3 The arrows in FIG. 2 show that the cooling water flows from the front direction (negative direction of the x-axis) to the depth direction (positive direction of the x-axis) of the drawing. Hydrogen is supplied from the positive direction of the z-axis to the negative direction of the z-axis in the manifold hole 20 on one side. Hydrogen passes through the space SP1 from the negative direction of the x-axis to the positive direction of the x-axis. Hydrogen is recovered by passing from the negative direction of the z-axis to the positive direction of the z-axis in the manifold hole 20 on the other side.

[0022] Oxygen is supplied from the negative z-axis direction to the positive z-axis direction in one manifold hole 22. Oxygen passes through the space SP3 from the positive x-axis direction to the negative x-axis direction. Oxygen passes through the other manifold hole 22 from the positive z-axis direction to the negative z-axis direction and is recovered.

[0023] The cooling water is supplied to the manifold hole 21 on one side from the positive direction of the z-axis toward the negative direction of the z-axis. The cooling water passes through the closed space CS from the negative direction of the x-axis toward the positive direction of the x-axis. The cooling water passes through the manifold hole 21 on the other side from the negative direction of the z-axis toward the positive direction of the z-axis and is recovered. That is, in the fuel cell 10, in order to prevent the cooling water from leaking from the fuel cell 10, the sealing portion 12 is provided, thereby forming the closed space CS, so that the cooling water passes through the closed space CS.

[0024] <Structure of the sealing part> Next, refer to Figure 4 , the structure of the sealing portion of the fuel cell is described. Figure 4 This is a cross-sectional view of a sealing portion of the fuel cell according to Embodiment 1. Figure 4 The yz plane view shows the separator 14 and the sealing portion 12 on one side of the stacked body 11 , and the separator 14 and the membrane electrode assembly 13 on the other side of the stacked body 11 are omitted.

[0025] like Figure 4 As shown in FIG. 1 , the sealing portion 12 is composed of a sealing member 31 and a resin layer 30. The sealing portion 12 includes the resin layer 30 disposed between the spacer 14 and the sealing member 31. Figure 4 In the example shown, the sealing portion 12 is formed so that the sealing member 31 covers the surface and side surfaces of the resin layer 30 disposed on the spacer 14. Figure 4 In the example shown, the sealing portion 12 may be formed by forming the sealing member 31 so as to be laminated on the entire or a part of the surface of the resin layer 30 on the spacer 14 .

[0026] The sealing member 31 is made of a rubber material, such as EPDM. The resin layer 30 is made of a thermoplastic resin and is a sheet-like solid. Examples of the thermoplastic resin are polyethylene, which is a crystalline resin, and polyvinyl chloride, which is a non-crystalline resin.

[0027] As described above, the fuel cell according to the first embodiment has a resin layer 30 disposed between the spacer 14 and the sealing member 31 of the stack. The resin layer 30 is in sheet form and is in close contact with the spacer 14, so there are few defects such as voids at the interface between the spacer 14 and the sealing member 31. As a result, unevenness in bonding strength can be suppressed at the interface between the spacer 14 and the sealing member 31. Therefore, peeling at the interface between the spacer 14 and the sealing member 31 is suppressed, and the bonding strength between the spacer 14 and the sealing member 31 is high.

[0028] <Method for manufacturing fuel cell> Next, refer to Figure 5 , Figure 6 , a method for manufacturing a fuel cell is described. Figure 5 , Figure 6 This is a schematic diagram showing an example of a method for manufacturing a fuel cell according to Embodiment 1. Figure 5 A perspective view showing a spacer and a resin layer during the manufacturing process of a fuel cell. Figure 6 A cross-sectional view showing a spacer, a resin layer, and a sealing member during the manufacturing process of a fuel cell. Figure 5 , steps ST1 to ST3 in the manufacturing process of the fuel cell are shown. Figure 6 , steps ST4 to ST7 in the manufacturing process of the fuel cell are shown.

[0029] exist Figure 5 , Figure 6 In FIG. 1 , a method for manufacturing a fuel cell using a method for injection molding the sealing member 31 is shown. Figure 5 , Figure 6 In the example of the fuel cell manufacturing method shown, step ST1 to step ST7 are performed in sequence.

[0030] Reference Figure 5 Steps ST1 to ST3 are described below. First, prepare the spacer 14 (step ST1). Figure 5 As shown, the spacer 14 is provided with manifold holes 20 , 21 , 22 .

[0031] Next, a sheet-like resin layer 30 is arranged on the spacer 14 (step ST2). More specifically, the resin layer 30 is arranged on the surface of the spacer 14 and is temporarily bonded to the spacer 14. This is to prevent the resin layer 30 from falling off from the spacer 14 due to the injection of the sealing component in step ST5. In addition, this is to prevent the position of the resin layer 30 from deviating from the spacer 14 when the spacer 14 with the resin layer 30 on the surface is arranged in the mold in step ST4. The temporary bonding of the resin layer 30 to the spacer 14 is performed, for example, by laser irradiation, thermal compression bonding, ultrasonic compression bonding, and vibration compression bonding.

[0032] Next, the remaining portion of the resin layer 30 is removed (step ST3). More specifically, the remaining portion of the resin layer 30 is removed so that the resin layer 30 is disposed around the periphery of the spacer 14 and the periphery of the manifold holes 20 and 22. The remaining portion of the resin layer 30 is removed by, for example, laser irradiation or a cutter.

[0033] Reference Figure 6, step ST4 to step ST7 are explained. Following step ST3, a spacer 14 having a resin layer 30 temporarily bonded to the surface is arranged on the mold (step ST4). The mold has a pair of movable molds 50 and 51 that can be opened and closed. The movable molds 50 and 51 are opened, and a spacer 14 having a resin layer 30 temporarily bonded to the surface is arranged between the movable molds 50 and 51. Thereafter, the pair of movable molds 50 and 51 are closed. Thus, a space SP4 is formed between the mold and the spacer 14 having a resin layer 30 temporarily bonded to the surface. In addition, one of the movable molds 50 and 51 may also be a fixed mold.

[0034] Next, the sealing member 31 is injected to fill the space SP4 inside the mold (step ST5 ). Thus, the sealing member 31 is filled to cover the spacer 14 having the resin layer 30 temporarily bonded to the surface, so that the resin layer 30 can be arranged between the spacer 14 and the sealing member 31 .

[0035] Next, by heating the inside of the mold, at least both the sealing component 31 and the resin layer 30 are heated (step ST6). More specifically, by heating the inside of the mold, the sealing component 31 is heated. As a result, the sealing component 31 is cross-linked and solidified. In addition, by heating the inside of the mold, the resin layer 30 is heated and melted. Thereafter, the resin layer 30 is cooled and solidified, so that the spacer 14 is bonded to the sealing component 31 to form the sealing portion 12. In this way, in step ST6, by a single heating treatment, the resin layer 30 can be melted while the sealing component 31 is cross-linked, and the spacer 14 can be bonded to the sealing component 31. In addition, the cooling method of the resin layer 30 can be any method as long as it can cool the resin layer 30, such as natural cooling, water cooling, air cooling, etc.

[0036] Next, the movable molds 50 and 51 are opened to remove the spacer 14 (step ST7). The removed spacer 14 has the resin layer 30 between the sealing member 31 and the spacer 14. In other words, in step ST7, the spacer 14 and the sealing portion 12 formed in such a manner that the sealing member 31 covers the surface and side surfaces of the resin layer 30 disposed on the spacer 14 are integrated.

[0037] Like this, in Figure 5 and Figure 6In the manufacturing method of the fuel cell shown, the sealing member 31 is filled in a manner that the spacer 14 with the resin layer 30 temporarily bonded to the surface is covered, so that the resin layer 30 can be arranged between the spacer 14 and the sealing member 31. After that, the sealing member 31 is cross-linked and solidified by being heated. In addition, the resin layer 30 is heated and melted and then cooled and solidified, so that the spacer 14 and the sealing member 31 are bonded to form the sealing portion 12. Like this, in the manufacturing method of the fuel cell involved in embodiment 1, a fuel cell with a high bonding strength between the spacer 14 and the sealing member 31 can be manufactured.

[0038] <Modification> Here, in Figure 5 and Figure 6 A method for manufacturing a fuel cell using a method of injection molding the sealing component 31 is shown in the figure. However, the method for manufacturing a fuel cell according to the first embodiment is not limited to this method, and may be a method for manufacturing a fuel cell in which the sealing component 31 is transferred by swapping step ST4 and step ST5. The method for manufacturing a fuel cell in which the sealing component 31 is transferred will be described in more detail. In the method for manufacturing a fuel cell in which the sealing component 31 is transferred, steps ST1 to ST3, step ST6, and step 7 are identical to the steps ST4 to ST5. Figure 5 and Figure 6 The same as shown, so the description is omitted.

[0039] In the method for manufacturing a fuel cell in which the sealing member 31 is transferred, Figure 6 The steps corresponding to step ST4 and step ST5 shown in the figure are respectively indicated as step ST4 (transfer) and step 5 (transfer) for explanation. Figure 6 Provide explanation.

[0040] In step ST4 (transfer), the sealing member 31 is injected to fill the space SP4 inside the mold formed by closing the mold. In step ST5 (transfer), following step ST4 (transfer), the mold is opened, and the spacer 14 having the resin layer 30 temporarily bonded to the surface is arranged on the mold. Thus, the resin layer 30 can be arranged between the spacer 14 and the sealing member 31. Therefore, in step ST6, by heating the inside of the mold, at least both the sealing member 31 and the resin layer 30 can be heated.

[0041] As described above, in the method for manufacturing a fuel cell in which the sealing member 31 is injection molded and the sealing member 31 is transferred, the resin layer 30 is melted while the sealing member 31 is cross-linked, and the spacer 14 is bonded to the sealing member 31, thereby forming the sealing portion 12. Therefore, in the method for manufacturing a fuel cell in which the sealing member 31 is injection molded and the sealing member 31 is transferred, a fuel cell having a high bonding strength between the spacer and the sealing member can be manufactured.

[0042] Furthermore, in the manufacturing method of the fuel cell involved in the first embodiment, it is not limited to melting the resin layer 30 while cross-linking the sealing member 31, and the resin layer 30 may be melted after cross-linking the sealing member 31. That is, the manufacturing method of the fuel cell involved in the first embodiment may also be a manufacturing method of the fuel cell in which the resin layer 30 is attached to the sealing member 31 after cross-linking.

[0043] The manufacturing method of the fuel cell in which the resin layer 30 is bonded to the sealing member 31 after crosslinking is described in more detail. In the manufacturing method of the fuel cell in which the resin layer 30 is bonded to the sealing member 31 after crosslinking, steps ST1 to ST3 and step 7 are Figure 5 and Figure 6 The same as shown, so the description is omitted.

[0044] In the method for manufacturing a fuel cell in which the resin layer 30 is bonded to the sealing member 31 which has been cross-linked, Figure 6 The steps corresponding to steps ST4 to ST6 are respectively indicated as steps ST4 (bonding) to ST6 (bonding) and described. Figure 6 Provide explanation.

[0045] In step ST4 (lamination), the sealing member 31 is cross-linked. More specifically, Figure 6 The sealing member 31 is injected and filled into the space SP4 inside the mold shown, and the sealing member 31 is cross-linked by heating. Here, in step ST4 (bonding), the cross-linked sealing member 31 may be placed on the mold. That is, in step ST4 (bonding), the cross-linking of the sealing member 31 only needs to be completed before the placement of the resin layer 30 in step ST5.

[0046] In step ST5 (lamination), the resin layer 30 is placed in contact with the sealing member 31 which has been cross-linked in step ST4. More specifically, the mold is opened, and the resin layer 30 is placed between the spacer 14 and the sealing member 31 which has been cross-linked. Figure 6 However, the cross-linking of the sealing member 31 is completed, which is equivalent to the state of step ST5 shown in FIG. Figure 6 The step ST5 shown is different.

[0047] In step ST6 (bonding), the resin layer 30 is heated and melted to bond the spacer 14 and the sealing member 31 to form the sealing portion 12. More specifically, the resin layer 30 is heated and melted by heating the inside of the mold. Thereafter, the resin layer 30 is cooled and solidified, so that the spacer 14 and the sealing member 31 that has been cross-linked are bonded to form the sealing portion 12.

[0048] Like this, in the manufacturing method of the fuel cell that makes the resin layer 30 adhere to the sealing component 31 that has been cross-linked, the sealing component that has been cross-linked and solidified is arranged in contact with the resin layer. By heating the mold, the resin layer is heated and melted and then cooled and solidified, so the spacer and the sealing component are bonded to form a sealing portion. Therefore, in the manufacturing method of the fuel cell that makes the resin layer 30 adhere to the sealing component 31 that has been cross-linked, a fuel cell with a high bonding strength between the spacer and the sealing component can be manufactured.

[0049] <Adhesion Strength> Next, the adhesive strength of the sealing portion of the fuel cell according to Embodiment 1 will be described with reference to Table 1. Table 1 is a table showing the results corresponding to the evaluation items in Examples 1 to 11 having different configurations of the sealing portion of the fuel cell.

[0050] [Table 1]

[0051] As shown in Table 1, in each structure of the sealing part of the fuel cell, the material of the spacer, the material of the resin layer, the temporary bonding method of the resin layer and the spacer, the material of the sealing component, the molding method of the sealing part and the heating temperature of the mold are recorded. The spacer is a substrate with stainless steel or resin as the main material. In Table 1, the main material is recorded in the column of the material of the spacer, and stainless steel is represented as SUS (Steel Use Stainless). The resin layer is a thermoplastic sheet with nylon resin and polypropylene resin as the main material. In Table 1, the main material is recorded in the column of the material of the resin layer, and polypropylene is represented as PP (polypropylene).

[0052] The temporary bonding method between the resin layer and the spacer is laser-based bonding or thermal compression bonding. The sealing component is EPDM. In Table 1, EPDM is indicated as EPDM (Ethylene Propylene Diene Methylene Linkage) in the column of the material of the sealing component. The molding method of the sealing part is, as mentioned above, one of transfer molding, injection molding, and lamination molding. In addition, the heating temperature of the mold is one of 190°C, 170°C, and 160°C.

[0053] Table 1 records three evaluation items: presence or absence of contamination of the spacer, the detachment of the temporary bonding between the resin layer and the spacer, and the results of the peel test, and shows the results of Examples 1 to 11 corresponding to each evaluation item. The presence or absence of contamination of the spacer was determined by visual inspection. The detachment of the temporary bonding between the resin layer and the spacer was evaluated in three stages: a case where there was no detachment of the temporary bonding (A), a case where a portion of the temporary bonding surface detached but the position of the resin layer relative to the spacer did not deviate (B), and a case where the temporary bonding detached (C).

[0054] In the results of the peel test shown in Table 1, the state of the damaged part and the proportion of the cohesive damaged part of the resin layer in the damaged part are shown. The cohesive damage of the resin layer indicates the state of damage caused by cracks entering the interior of the resin layer. The interface damage indicates the state of damage caused by cracks entering the interface between the resin layer and the spacer. Therefore, the high proportion of the cohesive damaged part of the resin layer in the damaged part indicates that the proportion of damage inside the resin layer is higher than the damage at the interface between the sealing component and the spacer. That is, the higher the proportion of the cohesive damaged part of the resin layer in the damaged part, the higher the bonding strength of the sealing part, which is a better result.

[0055] Embodiments 1, 6, and 7 shown in Table 1 are described. In Embodiments 1, 6, and 7, although the molding methods of the sealing portion are different, the structures other than the molding methods of the sealing portion are the same. In any of Embodiments 1, 6, and 7, contamination of the spacer was not confirmed. In addition, in any of Embodiments 1, 6, and 7, there was no detachment of the temporary bonding between the spacer and the resin layer. Furthermore, in any of Embodiments 1, 6, and 7, the state of the damaged portion was a mixed state of the resin layer, cohesive damage, and interface damage.

[0056] In Examples 1 and 6, the ratio of the cohesive failure part of the resin layer in the broken part was more than 90%, whereas in Example 7, the ratio of the cohesive failure part of the resin layer in the broken part was 51% to 70%. That is, the following result is shown: in the manufacturing method of the fuel cell according to Embodiment 1, when the molding method of the sealing part is transfer molding or injection molding, the bonding strength between the spacer and the sealing member is higher than that in the case of lamination molding.

[0057] In addition, in Examples 1 and 2, although the materials of the resin layer are different, the structures other than the materials of the resin layer are the same. In both Examples 1 and 2, the proportion of the cohesive failure part of the resin layer in the failure part is more than 90%. That is, in the manufacturing method of the fuel cell involved in Embodiment 1, regardless of the material of the resin layer, a fuel cell with high bonding strength between the spacer and the sealing member can be manufactured.

[0058] Furthermore, in Examples 1 and 5, although the materials of the spacers are different, the structures other than the materials of the spacers are the same. In both Examples 1 and 5, the proportion of the cohesive failure part of the resin layer in the failure part is more than 90%. That is, in the manufacturing method of the fuel cell involved in Embodiment 1, regardless of the material of the spacer, a fuel cell with high bonding strength between the spacer and the sealing member can be manufactured.

[0059] Here, the melting point of the resin layer is about 170°C in the case of nylon resin. In Examples 1, 8, and 10, the material of the resin layer is nylon resin, and the results of the peel test show better and better results in the order of Examples 1, 8, and 10 in which the heating temperature of the mold is from high to low. That is, by heating the mold to a temperature above the melting point of the resin layer, the proportion of the cohesive destruction part of the resin layer in the destruction part can be increased, and a fuel cell with high bonding strength between the spacer and the sealing component can be manufactured. In addition, the melting point of the resin layer is about 115°C in the case of the polypropylene resin shown in Table 1.

[0060] As described above, in the method for manufacturing a fuel cell according to Embodiment 1, it is possible to manufacture a fuel cell having a high bonding strength between the separator and the sealing member.

[0061] In addition, the present disclosure is not limited to the above-described embodiments, and can be appropriately modified within a scope not departing from the gist. According to the disclosure as described above, it is obvious that the embodiments of the present disclosure can be changed in many ways. These changes should not be regarded as departing from the spirit and scope of the present disclosure, and all such modifications obvious to those skilled in the art are intended to be included in the scope of the appended claims.

Claims

1. A method for manufacturing a fuel cell, the fuel cell comprising: a laminate including a membrane electrode assembly and a pair of separators sandwiching the membrane electrode assembly; and a sealing portion provided so as to form a sealed space with respect to a gap formed between the stacked bodies adjacent to each other in a stacking direction by stacking a plurality of the stacked bodies at predetermined intervals, in, In this manufacturing method, the resin layer provided between the spacer and the sealing member is melted to bond the spacer and the sealing member, thereby forming the sealing portion.

2. The method for manufacturing a fuel cell according to claim 1, in, In a state where the resin layer is disposed between the spacer and the sealing member, at least both the sealing member and the resin layer are heated. Thus, the sealing member is cross-linked and the resin layer is melted, so that the spacer and the sealing member are bonded together.

3. The method for manufacturing a fuel cell according to claim 1, in, After the sealing member is cross-linked, the resin layer is disposed at a position in contact with the sealing member, and the resin layer is heated to melt the resin layer, thereby bonding the spacer and the sealing member.

4. The method for manufacturing a fuel cell according to claim 1 or 2, in, The spacer having the resin layer temporarily bonded to the surface is arranged in a mold for molding the sealing portion, The sealing member is injected into and filled in the mold, thereby providing the resin layer between the spacer and the sealing member.

5. A fuel cell comprising a plurality of stacked bodies including a membrane electrode assembly and a pair of separators sandwiching the membrane electrode assembly, stacked at predetermined intervals, in, The sealing portion provided so as to form a sealed space with respect to a gap formed between the stacked bodies adjacent to each other in the stacking direction of the stacked bodies includes a resin layer between the spacer and the sealing member of the stacked body.

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