Fuel battery manufacturing method

Abstract

To provide a technique that can effectively suppress warping of cells during the manufacture of fuel batteries.SOLUTION: A fuel battery manufacturing method includes the steps of: preparing a cell precursor including a membrane-electrode-gas diffusion layer assembly of a fuel battery, a pair of separators arranged so as to sandwich the assembly, and a thermoplastic resin; heating the thermoplastic resin using a first heating mold and a second heating mold arranged opposite each other and capable of heating the cell precursor; and cooling the thermoplastic resin using a first cooling mold and a second cooling mold arranged opposite each other and capable of cooling the cell precursor. In this manufacturing method, a temperature difference is generated in at least a part of the contact surfaces where the first heating mold and the second heating mold contact the cell precursor and / or at least a part of the contact surfaces where the first cooling mold and the second cooling mold contact the cell precursor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a method for manufacturing a fuel cell.

[0002] For example, a fuel cell includes a cell composed of an electrode composite and a pair of separators as a constituent unit. The cell is integrated by heating and cooling the thermoplastic resin of a cell precursor in which the thermoplastic resin is interposed between the electrode composite and the separator. Patent Document 1 describes a method of performing two cooling steps to suppress warping of the cell. In this method, the latter cooling step is performed at a lower temperature than the former cooling step. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-126256 Summary of the Invention [Problem to be solved by the invention]

[0004] The separator surface of the cell has a complex uneven shape for the flow path of gas cooling water. Therefore, the upper and lower press dies for cooling have different shapes of the upper and lower press surfaces, and the area and region for pressing the cell precursor do not match between the upper and lower dies. In addition, the press surfaces on one side of the die are not formed symmetrically. Therefore, even if the cell precursor is pressed at the same temperature using the upper and lower press dies in the heating process and cooling process, the heating effect and cooling effect are uneven on the upper and lower press surfaces and within the press surface on one side. For this reason, warping and waviness of the cell could not be sufficiently suppressed.

[0005] The present specification provides a technique that can effectively suppress warping of cells during the manufacture of fuel cells. [Means for solving the problem]

[0006] The technology disclosed in this specification is embodied in a method for manufacturing a fuel cell. The method includes the steps of preparing a cell precursor including a membrane-electrode-gas diffusion layer assembly of a fuel cell, a pair of separators arranged to sandwich the assembly, and a thermoplastic resin, a heating step of heating the thermoplastic resin using a first heating mold and a second heating mold arranged opposite each other and capable of heating the cell precursor, and a cooling step of cooling the thermoplastic resin using a first cooling mold and a second cooling mold arranged opposite each other and capable of cooling the cell precursor. In this manufacturing method, a temperature difference is generated in at least a part of the contact surfaces where the first heating mold and the second heating mold contact the cell precursor and / or at least a part of the contact surfaces where the first cooling mold and the second cooling mold contact the cell precursor.

[0007] The inventors have found that when the cell precursor is heated and / or cooled in a facing mold, a suitable temperature differential exists to inhibit warping.

[0008] According to this manufacturing method, a temperature difference is generated on at least a portion of the contact surfaces of the first and second heating molds used in the heating step and the first and second cooling molds used in the cooling step that come into contact with the cell precursor, and thus such contact surfaces can be heated and / or cooled to the same temperature, thereby suppressing or avoiding warping that occurs when the thermoplastic resin is heated and cooled.

[0009] Furthermore, according to this manufacturing method, necessary and sufficient heating and cooling effects can be imparted to the cell precursor, making it possible to shorten the heating and cooling steps or reduce the number of heating and cooling steps.

[0010] The technology disclosed in this specification is embodied in a manufacturing device for a fuel cell. The manufacturing device includes a first heating mold and a second heating mold disposed opposite each other to heat the thermoplastic resin of a cell precursor including a membrane-electrode-gas diffusion layer assembly of the fuel cell, a pair of separators disposed to sandwich the assembly, and a thermoplastic resin interposed between the assembly and the separator, a first cooling mold and a second cooling mold disposed opposite each other to cool the thermoplastic resin of the cell precursor, and a temperature adjustment device that generates a temperature difference in at least a part of the contact surfaces where the first heating mold and the second heating mold contact the cell precursor and / or at least a part of the contact surfaces where the first cooling mold and the second cooling mold contact the cell precursor.

[0011] According to this manufacturing apparatus, a temperature difference is generated in at least a portion of the contact surfaces where the first heating mold and the second heating mold come into contact with the cell precursor, and / or at least a portion of the contact surfaces where the first cooling mold and the second cooling mold come into contact with the cell precursor. Therefore, the entire contact surfaces can be heated and / or cooled to the same temperature, thereby suppressing or avoiding warping caused by heating and cooling thermoplastic resin. [Brief description of the drawings]

[0012] [Figure 1] 1 is a diagram showing an outline of an example of a manufacturing process for a fuel cell. [Diagram 2] FIG. 2 is a plan view of a cell of a fuel cell. [Diagram 3] FIG. 2 is a cross-sectional view showing the relationship between the upper and lower dies of a cooling press die and a cell precursor. [Figure 4] 1 is a combination of a plan view of a cell and a diagram showing the relationship between the temperature difference ΔT between the upper and lower dies and the warping force of the cell in the vicinity of the flow channel. [Diagram 5] FIG. 2 is a cross-sectional view showing the relationship between the upper and lower dies of a cooling press die and a cell precursor. [Figure 6] FIG. 13 shows additional cooled regions in a cell precursor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] One aspect of the method for producing a fuel cell disclosed in the present specification (hereinafter, simply referred to as the production method) includes the steps of: preparing a cell precursor including a fuel cell membrane-electrode-gas diffusion layer assembly, a pair of separators arranged to sandwich the assembly, and a thermoplastic resin; heating the thermoplastic resin using a first heating mold and a second heating mold arranged opposite each other and capable of heating the cell precursor; and cooling the thermoplastic resin using a first cooling mold and a second cooling mold arranged opposite each other and capable of cooling the cell precursor. This production method includes generating a temperature difference in at least a part of the contact surfaces where the first heating mold and the second heating mold contact the cell precursor and / or at least a part of the contact surfaces where the first cooling mold and the second cooling mold contact the cell precursor.

[0014] In another aspect of the manufacturing method, the first cooling mold has a first cooling surface capable of being cooled by contacting a first surface of the cell precursor, and the second cooling mold has a second cooling surface capable of being cooled by contacting a second surface of the cell precursor, and the cooling step can include generating a temperature difference in at least a portion of the first cooling surface and the second cooling surface. According to this aspect, by generating a temperature difference in at least a portion of the first cooling surface and the second cooling surface, warping can be effectively and more reliably suppressed or avoided.

[0015] Another aspect of the manufacturing method can include cooling at least the first portion to a temperature lower than that of the second portion when a contact area of ​​a first portion of the first cooling surface with the cell precursor is smaller than a contact area of ​​a second portion of the second cooling surface facing the first portion with the cell precursor, and cooling at least the second portion to a temperature lower than that of the first portion when a contact area of ​​the second portion is smaller than a contact area of ​​the first portion. According to this manufacturing method, it is possible to cool the thermoplastic resin while suppressing warpage by suppressing or avoiding a difference in cooling effect due to a difference in contact area between the first portion and the second portion.

[0016] Another aspect of the manufacturing method may include a cooling step using one or both of the first cooling mold having the first cooling surface including a surface for cooling the region where the thermoplastic resin is interposed and a surface for cooling the region where the thermoplastic resin is not interposed, and the second cooling mold having the second cooling surface including a surface for cooling the region where the thermoplastic resin is interposed and a surface for cooling the region where the thermoplastic resin is not interposed. According to this manufacturing method, since the first cooling mold and the second cooling mold have a surface for cooling the region where the thermoplastic resin is not interposed in addition to the surface for cooling the region where the thermoplastic resin is interposed, it is possible to suppress or avoid the difference in cooling effect on the cell precursor of the surface for cooling the region where the thermoplastic resin is interposed, and to cool the thermoplastic resin while suppressing warping.

[0017] The above various other aspects of the fuel cell manufacturing method are all applicable to the first heating type, second heating type, first cooling type, second cooling type and temperature adjustment device in the fuel cell manufacturing apparatus.

[0018] First Embodiment Hereinafter, an embodiment of a method for manufacturing a fuel cell according to the present disclosure, more specifically, a method for manufacturing a cell of a fuel cell, etc. will be described with reference to the drawings. First, a general configuration of a fuel cell will be described below, and then a method for manufacturing a cell and a manufacturing apparatus for a fuel cell will be described. Fig. 1 shows an example of a cell manufacturing process, Fig. 2 shows a plan view of the cell, Fig. 3 shows the relationship between the upper and lower dies of a cooling press die and a cell precursor in a cell cooling process, and Fig. 4 shows the relationship between the temperature difference and the warping force in a pair of dies.

[0019] (Fuel cell) Although not shown in the figure, a fuel cell generally comprises a stack consisting of a laminate of multiple cells, equipped with current collectors, end plates, etc., a hydrogen gas distribution mechanism for the fuel gas, an air distribution mechanism for the oxidant gas, and a cooling mechanism for the fuel cell.

[0020] A plan view of a fuel cell 10 is shown in Figure 2. The cell 10 includes a membrane-electrode-gas diffusion layer assembly (MEGA) 12, a resin frame 14 surrounding the MEGA 12, and a pair of separators 16, 18 sandwiching them between them.

[0021] Although not shown, MEGA 12 includes a membrane-electrode assembly and gas diffusion layers laminated on both sides of the membrane-electrode assembly, and is disposed in a rectangular opening of resin frame 14. The membrane-electrode assembly is configured with an anode and a cathode disposed on both sides of the membrane, and is supplied with fuel gas and oxidant gas for power generation.

[0022] The resin frame 14 is formed, for example, in a rectangular frame shape surrounding the MEGA 12. The resin frame 14 has a plurality of manifold holes H1 to H6 that form the manifolds M1 to M6 on its outer edge. The resin frame 14 melts or softens when heated and is bonded to the separators 16, 18. At least the surface layer of the resin frame 14 that faces the separators 16, 18 is made of a thermoplastic resin with a softening point of, for example, about 160°C.

[0023] The separators 16, 18 are made of a material having gas barrier properties and electrical conductivity, such as a carbon member such as dense carbon made by compressing carbon particles to make it gas impermeable, or a metal member such as press-molded stainless steel or titanium. One of the separators 16, 18 is the anode side separator 16 arranged on surface A, and the other is the cathode side separator 18 arranged on surface B. Surface A is an example of the first surface of the cell precursor in this specification.

[0024] The anode-side separator 16 has a plurality of striated refrigerant flow paths 20 for distributing the refrigerant on surface A, which is the surface opposite to MEGA12. The separator 16 has a plurality of striated flow grooves for distributing the fuel gas on the surface on the MEGA12 side, not shown. The cathode-side separator 18 has a plurality of striated flow grooves for distributing the oxidant gas on the surface on the MEGA12 side, and has a plurality of striated refrigerant flow paths for distributing the refrigerant on surface B, which is the surface opposite to MEGA12. Surface B is an example of the second surface of the cell precursor in this specification.

[0025] The separators 16 and 18 have a plurality of manifold holes H1 to H6 that form the manifolds M1 to M6. The manifold holes H1 and H2 form part of a fuel gas flow path, the manifold holes H3 and H4 form part of an oxidant gas flow path, and the manifold holes H5 and H6 form part of a coolant flow path.

[0026] The manifold holes H1 and H2 are provided to discharge the fuel gas supplied from the manifold M1 to the manifold M2 via the fuel gas flow path. The manifold holes H3 and H4 are provided to discharge the oxidizer gas supplied from the manifold M3 to the manifold M4 via the oxidizer gas flow path. The manifold holes H5 and H6 are provided to discharge the coolant supplied from the manifold M5 to the manifold M6 via the coolant flow path 20, etc.

[0027] In the cell 10, the fuel gas flow path, the oxidant gas flow path, and the manifold holes H1 to H6 are separated by a resin frame 14 or a separately provided gasket or the like.

[0028] (Fuel Cell Manufacturing Method) Next, a method for producing a fuel cell according to the present disclosure will be described with reference to FIGS.

[0029] The manufacturing method of this embodiment includes at least a step of manufacturing the cell 10. A fuel cell stack is constructed by stacking a plurality of cells 10 and installing current collectors and the like. A fuel cell system is constructed by further connecting a fuel gas distribution mechanism, an oxidant gas distribution mechanism, and a coolant distribution mechanism to this fuel cell stack. Stacking the cells 10, installing current collectors and the like, and connecting the fuel gas distribution mechanism and the like can be performed by methods well known to those skilled in the art.

[0030] This manufacturing method includes a step S1 of preparing the cell precursor 30, a step S2 of hot-pressing the cell precursor 30, and a step S3 of cold-pressing the cell precursor 30.

[0031] In the preparation step S1, a cell precursor 30 is prepared in which the MEGA 12 held by the resin frame 14 is sandwiched between a pair of separators 16, 18. The cell precursor 30 is in a state in which the MEGA 12, the resin frame 14, and the pair of separators 16, 18 are joined together, and the same reference numerals are used for common components.

[0032] Next, in the hot pressing step S2, the cell precursor 30 is heated under pressure at a temperature exceeding the softening point of the resin frame 14.

[0033] Although not shown, in the heat press step S2, the cell precursor 30 is heated by a pair of upper and lower dies arranged opposite to each other above and below a heat press die. More specifically, the cell precursor 30 is placed on the lower die, and the upper die is lowered to heat and press the resin frame 14 via the separators 16 and 18 between the upper and lower dies heated to a predetermined temperature. This softens the thermoplastic resin of the resin frame 14, and the separators 16 and 18, MEGA 41, and resin frame 14 are in close contact with each other. The upper and lower dies of the heat press die are an example of the first heating die and the second heating die disclosed in this specification.

[0034] Next, a cooling press step S3 is performed. As shown in Fig. 3, in the cooling press step S3, the A-side and the B-side of the cell precursor 30 are cooled to temperatures that are lower than the softening point of the resin frame 14 and are different from each other. Hereinafter, an embodiment in which the A-side and the B-side of the cell precursor 30 are cooled while being pressed at different temperatures using a cooling press mold 40 will be described.

[0035] Fig. 3 shows a state in which a cell precursor 30 corresponding to the cell 10 is about to be cooled by a cooling press mold 40. Fig. 3 shows the relationship between the cell precursor 30 corresponding to line III-III of the cell 10 shown in Fig. 2 and the cooling press mold 40. The cooling press mold 40 includes an upper mold 42 and a lower mold 44 arranged opposite each other above and below. The upper mold 42 and the lower mold 44 of the cooling press mold 40 are an example of the first cooling mold and the second cooling mold disclosed in this specification.

[0036] The upper die 42 has a cooling surface 42a for cooling a portion of the surface A of the cell precursor 30 that is to be sealed by the resin frame 14. The cooling surface 42a has cooling portions 42b at locations corresponding to the C-edge and D-edge (portions where the manifold holes H1 to H6 are not formed in FIG. 3) of the outer periphery surrounding the power generation region of the cell precursor 30. The cooling portions 42b are provided as convex portions that contact the surface A of the cell precursor 30 to apply pressure and cool it. The cooling surface 42a is an example of a first cooling surface disclosed in this specification, and the cooling portions 42b are an example of a first portion disclosed in this specification.

[0037] Similarly, the lower die 44 has a cooling surface 44a for cooling a portion of the surface B of the cell precursor 30 that is to be sealed by the resin frame 14. The cooling surface 44a has cooling portions 44b, for example, at locations corresponding to the C and D edges of the outer periphery surrounding the power generation region of the cell precursor 30. The cooling portions 44b are provided as convex portions that contact the surface B of the cell precursor 30 to cool and pressurize it. The cooling surface 44a is an example of a second cooling surface disclosed in this specification, and the cooling portions 44b are an example of a second portion disclosed in this specification.

[0038] The upper die 42 and the lower die 44 of the cooling press die 40 are equipped with a temperature control device (not shown) that can set the cooling surface 42a of the upper die 42 and the cooling surface 44a of the lower die 44 to different temperatures. Generally, temperature control devices such as cooling devices in the cooling press die 40 are well known. For example, a cooling structure in which refrigerant flow paths are provided along the vicinity of the cooling surfaces 42a, 44a inside the upper die 42 and the lower die 44 can be mentioned. Here, by circulating refrigerants adjusted to different temperatures through the respective cooling paths of the upper die 42 and the lower die 44, the temperatures of the respective cooling surfaces 42a, 44a can be made different.

[0039] In addition, such a cooling press mold 40 can be obtained by providing a temperature control device having a refrigerant supply source or a refrigerant supply path capable of supplying refrigerants of different temperatures to the upper mold 42 and the lower mold 44, as well as a temperature control device that adjusts the amount of refrigerant on the cooling surfaces 42a, 44a to make the temperatures of the cooling surfaces 42a, 44a different.

[0040] In the cooling press step S3, a cooling press mold 40 is used in which the temperatures of the cooling surface 42a of the upper mold 42 and the cooling surface 44a of the lower mold 44 are both set in advance to a temperature lower than the softening temperature of the thermoplastic resin of the resin frame 14, and the temperature of the cooling surface 42a is cooled to a temperature lower than that of the cooling surface 44a. That is, a cooling press mold 40 is used in which a temperature difference is generated in advance between the cooling surfaces 42a, 44a, with the cooling surface 42a having a lower temperature.

[0041] In this way, even if the cooling portion 42b has a smaller contact area than the cooling portion 44b, the cooling portion 42b has a lower temperature than the cooling portion 44b, so that at least the transmission of different cooling effects between the top and bottom to the C edge and D edge of the cell precursor 30 is suppressed or avoided, and as a result, the thermoplastic resin at the C edge and D edge can be cooled more evenly from the top and bottom to solidify the thermoplastic resin. This makes it possible to suppress or avoid warping of the cell 10.

[0042] 4 shows an example of an evaluation result of a cooling press mold 40 in which the contact area of ​​the cooling portion 42b corresponding to the C edge and D edge of the cell precursor 30 with the cell precursor 30 is smaller than that of the cooling portion 44b. FIG. 4 shows an evaluation result of the relationship between the temperature difference ΔT (cooling temperature of the cooling surface 44a-cooling temperature of the cooling surface 42a) between the cooling surfaces 42a, 44a of the cooling press mold 40 and the warpage of the finally obtained cell 10. The warpage was evaluated as a warpage force (N) (a warpage force that is convex toward the A surface direction is a positive warpage force) detected at a part of the outer periphery of each of the manifold hole H1 which is a supply port of hydrogen as a fuel gas of the cell 10 shown in FIG. 2, the manifold hole H2 which is a discharge port of hydrogen, the manifold hole H3 which is a supply port of oxygen as an oxidizing gas, and the manifold hole H4 which is a discharge port of oxygen. In the graph of FIG. 4, the REF in the leftmost column in each region has a ΔT of zero, and ΔT1 to ΔT5 are arranged so that ΔT gradually increases to the right.

[0043] As shown in FIG. 4, it was confirmed that at each location, within a certain range of ΔT, the warping force tended to decrease compared to when ΔT was zero.

[0044] From the above, by generating a temperature difference between the cooling surface 42a of the upper die 42 and the cooling surface 44a of the lower die 44 of the cooling press die 40 and cooling the cell precursor 30, warping due to uneven cooling effect due to the size of the contact area between the cooling surfaces 42a, 44a and the cell precursor 30 can be suppressed or avoided.

[0045] Furthermore, by carrying out such a cold pressing process, for example, it is possible to obtain a cell in which warpage is suppressed or avoided by carrying out only a single cold pressing process for a short time, without carrying out multiple cooling processes as in the conventional method. That is, it is possible to obtain a cell in which warpage is suppressed in a short time.

[0046] The temperature difference generated between the cooling surfaces 42a, 44a can be set appropriately by performing evaluation experiments based on the present disclosure. In the above explanation, the size of the contact area with the cooling parts 42b, 44b has been explained, but such a temperature difference setting may be effective even when the contact area varies over the entire cooling surfaces 42a, 44a. Furthermore, regardless of the size of the contact area between the cooling surfaces 42a, 44a and the cooling parts 42b, 44b, setting a temperature difference in at least a part of the cooling surfaces 42a, 44a may be effective from the viewpoint of their shapes, etc.

[0047] <Second embodiment> Next, another embodiment of the fuel cell manufacturing method etc. disclosed in this specification will be described with reference to Fig. 4. Fig. 5 shows a cross section taken along line III-III in Fig. 2 when a cell precursor 30 corresponding to the cell 10 shown in Fig. 2 is about to be cooled in a cooling press mold 140.

[0048] This manufacturing method has the same configuration as the first embodiment, except that a cooling press step S3 is performed using a cooling press mold 140 instead of the cooling press mold 40 used in the first embodiment. In this embodiment, cooling surfaces 142c and 142d of the cooling press mold 140 are cooled so as to generate a temperature difference. In the following description, only the cooling press step S3 using the cooling press mold 140 will be described, and descriptions of the other steps will be omitted.

[0049] In this cooling press step S3, a cooling press mold 140 is used. The cooling surface of an upper mold 142 of the cooling press mold 140 is configured so as to be able to generate a temperature difference within the surface. For example, as shown in FIG. 5, the upper mold 142 may be configured as a split type in which the cooling surface for cooling the cell precursor 30 while pressurizing it is split into two or more parts, and the temperature of each split part can be controlled individually. In addition to using a split type, such an upper mold 142 can also be obtained by using a refrigerant flow passage configured so that the size, number, and arrangement of the refrigerant flow passages, and the refrigerant supply source can be temperature-controllable.

[0050] As shown in FIG. 5, the cooling press mold 140 has an upper mold 142 divided into an upper mold 142a on the C edge side of the cell precursor 30 and an upper mold 142b on the D edge side. The upper mold 142a has a cooling surface 142c for the cell precursor 30, and the upper mold 142b has a cooling surface 142d for the cell precursor 30. The lower mold 144 has a cooling surface 144a for the cell precursor 30. Note that, on the C end side and the D end side of the cell precursor 30, the contact area of ​​the cooling surface 144a with the cell precursor 30 is larger than that of the cooling surfaces 142c and 142d. The upper mold 142 and the lower mold 144 of the cooling press mold 140 are an example of the first cooling mold and the second cooling mold disclosed in this specification, the cooling surfaces 142c and 142d are an example of the first cooling surface, and the cooling surface 144a is an example of the second cooling surface.

[0051] In the cooling press step S3, the cooling surfaces 142c, 142d, and 144a of the cooling press mold 140 are cooled in advance to a temperature lower than the softening point of the resin frame 14. The cooling surfaces 142c and 144a of the cooling press mold 140 are cooled to the same predetermined temperature, and the cooling surface 142d is cooled to a lower temperature than the cooling surface 142c. As a result, a temperature difference occurs between the cooling surfaces 142c and 142d. A temperature difference also occurs between the cooling surface 142d and the cooling surface 144a. As a result, the surface A of the cell precursor 30 is cooled at a lower temperature on the D edge side than on the C edge side, and the entire cooling surface 144a of the cell precursor 30 is cooled at the same temperature on the B edge side.

[0052] By using the cooling press mold 140 to cool the cooling surfaces 142c, 142d, and 144a at the above-mentioned temperature and by cooling the A and B sides of the cell precursor 30 while applying pressure, it is possible to suppress or avoid the different cooling effects at the top and bottom of the D edge of the cell precursor 30 being transmitted to the cell precursor 30, and as a result, the thermoplastic resin in the cell precursor 30 is cooled more evenly and solidified. This makes it possible to suppress or avoid warping of the cell 10. Also, by performing only a single cooling press step, it is possible to obtain a cell 10 in a short time with suppressed warping.

[0053] The form of the temperature difference generated on the cooling surfaces 142c, 142d of the upper mold 142 is not particularly limited, and an appropriate temperature difference can be set by conducting evaluation experiments based on the present disclosure, as in the first embodiment, if necessary.

[0054] The above-described embodiment is one embodiment of the technology disclosed in this specification, and does not limit the form for carrying out the technology.

[0055] In the first and second embodiments, the separators 16 and 18 of the cell precursor 30 are cooled and pressurized so as to seal the portions of the cell precursor 30 that should be sealed (portions where the thermoplastic resin is interposed, such as the resin frame 14), but the present invention is not limited to this. In order to suppress warping of the cell 10, cooling surfaces that come into contact with the separators 16 and 18 and cool them may be provided in regions where no thermoplastic resin is interposed and sealing is not intended. FIG. 6 shows cooled surfaces 50 and 52 that are not intended to be sealed on the A side of the cell precursor 30. For example, by providing the upper mold 42 and 142 with cooling surfaces 42a, 142c, and 142d that have cooling portions that cool the cooled surfaces 50 and 52 that are regions where no thermoplastic resin is interposed, the cooling effect on the A side and the B side of the cell precursor 30 can be made uniform, thereby suppressing or avoiding warping. The cooling surfaces 42a, 142c, 142d of the upper mold 42, 142 are an example of a first surface including a surface for cooling a region where a thermoplastic resin is interposed and a surface for cooling a region where the thermoplastic resin is not interposed, as disclosed in the present specification. Similarly, a surface to be cooled where no thermoplastic resin is interposed can be set on surface B of the cell precursor 30, and a second cooling surface including a surface for cooling a region where a thermoplastic resin is interposed and a surface for cooling a region where the thermoplastic resin is not interposed can be provided.

[0056] Furthermore, by appropriately arranging areas on the first and second cooling surfaces, such as the cooled surfaces 50 and 52 in Figure 6, which do not have a plastic resin interposed therebetween and are not intended to be sealed, it is possible to obtain an effect similar to that of generating a temperature difference between the upper molds 42, 142 and the lower molds 44, 144, even if a temperature difference is not generated between the upper molds 42, 142 and the lower molds 44, 144.

[0057] In the first and second embodiments, the thermoplastic resin that bonds the MEGA 12 and the separators 16, 18 is at least a part of the resin frame 14, but this is not limited to this. The resin frame 14 may be bonded with a thermoplastic resin agent such as a thermoplastic adhesive that is provided separately, and this thermoplastic resin may be heated and cooled.

[0058] In the first and second embodiments, the upper molds 42, 142a, 142b are cooled to a lower temperature than the lower molds 44, 144, but this is not limited to the above. Depending on the shape of the cooling surfaces 42a, 142c, 142d, 44a, 144a, the contact area with the cell precursor 30, and the like, the lower molds 44, 144 can also be cooled to a lower temperature than the upper molds 42, 142a, 142b.

[0059] In the first and second embodiments, the upper mold 42, 142a, 142b and the lower mold 44, 144 are cooled to a predetermined temperature in advance, and the cold press process is performed, but this is not limited to the above. For example, the temperature may be decreased or increased during the cold press time of the cold press process. Furthermore, such a decrease and increase in temperature may result in a temperature difference being generated in at least a part of the entire cooling surface. Furthermore, a temperature difference can also be generated by varying the temperature decrease rate or temperature increase rate, or by varying the temperature decrease start time or temperature increase start time.

[0060] In the first and second embodiments, the upper mold 42, 142a, 142b and the lower mold 44, 144 are cooled to different predetermined temperatures, but this is not limited to this. For example, the cooling surface 42a of the upper mold 42 etc. may be cooled so that the temperature difference is continuous, that is, the temperature is gradient.

[0061] In the first and second embodiments, in the cooling press process for cooling the thermoplastic resin of the cell precursor 30, the temperature is made different in at least a part of the heating surface which is the contact surface of the cooling press mold with the cell precursor 30, but the present invention is not limited to this. For example, in the hot pressing process of the cell precursor 30, a temperature difference may be generated in at least a part of the first heating surface and the second heating surface. This can also provide the same effect as that obtained by generating a temperature difference in at least a part of the first cooling surface and the second cooling surface in the cooling press process. Note that in both the hot pressing process and the cold pressing process, a temperature difference may be generated in at least a part of the contact surface of the hot pressing mold and the cold pressing mold.

[0062] In the hot press process, various aspects for generating a temperature difference in at least a portion of the heating surface of the upper mold and the heating surface of the lower mold of the hot press mold can be the same as those in the cold press process adopted in the first and second embodiments, as well as the various aspects additionally described above.

[0063] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings achieves multiple objectives simultaneously, and achieving one of the objectives itself has technical utility. [Explanation of symbols]

[0064] 10: cell, 12: MEGA, 14: resin frame, 16, 18: separator, 30: cell precursor, 40, 140: cooling press mold, 42, 142a, 142b: upper mold, 44, 144: lower mold, 42a, 44a, 142c, 142d, 44a, 144a: cooling surface

Claims

1. A method for manufacturing a fuel cell, comprising the steps of: preparing a cell precursor including a membrane-electrode-gas diffusion layer assembly of the fuel cell, a pair of separators arranged to sandwich the assembly, and a thermoplastic resin interposed between the assembly and the pair of separators; a heating step of heating the thermoplastic resin using a first heating mold and a second heating mold that are disposed opposite each other and capable of heating the cell precursor; a cooling step of cooling the thermoplastic resin using a first cooling mold and a second cooling mold that are arranged opposite to each other and capable of cooling the cell precursor; a temperature difference is generated in at least a portion of a contact surface where the first heating die and the second heating die contact the cell precursor, and / or in at least a portion of a contact surface where the first cooling die and the second cooling die contact the cell precursor. Manufacturing method.

2. the first cooling mold has a first cooling surface that is in contact with and can be cooled by a first surface of the cell precursor; the second cooling mold has a second cooling surface that is in contact with and can be cooled by a second surface of the cell precursor; The manufacturing method according to claim 1 , wherein the cooling step generates a temperature difference in at least a part of the first cooling surface and the second cooling surface.

3. the cooling step includes, when a contact area of ​​a first portion of the first cooling surface with the cell precursor is smaller than a contact area of ​​a second portion of the second cooling surface facing the first portion with the cell precursor, cooling at least the first portion to a temperature lower than that of the second portion; The manufacturing method according to claim 2 , further comprising the step of cooling at least the second portion so that the temperature of the second portion is lower than that of the first portion when the contact area of ​​the second portion is smaller than the contact area of ​​the first portion.

4. The manufacturing method described in claim 3, wherein the cooling process is a process using one or both of the first cooling mold having the first cooling surface including a surface for cooling the region where the thermoplastic resin is interposed and a surface for cooling the region where the thermoplastic resin is not interposed, and the second cooling mold having the second cooling surface including a surface for cooling the region where the thermoplastic resin is interposed and a surface for cooling the region where the thermoplastic resin is not interposed.

5. An apparatus for manufacturing a fuel cell, comprising: a first heating mold and a second heating mold disposed opposite each other for heating the thermoplastic resin of a cell precursor, the cell precursor comprising: a membrane-electrode-gas diffusion layer assembly of the fuel cell; a pair of separators disposed to sandwich the assembly; and a thermoplastic resin interposed between the assembly and the separators; a first cooling mold and a second cooling mold disposed opposite each other for cooling the thermoplastic resin of the cell precursor; a temperature control device that generates a temperature difference in at least a portion of the contact surfaces where the first heating die and the second heating die contact the cell precursor, and / or at least a portion of the contact surfaces where the first cooling die and the second cooling die contact the cell precursor; A manufacturing apparatus comprising:

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