Manufacturing device for membrane electrode assembly for fuel cell

Abstract

To provide a manufacturing device for a membrane electrode assembly for a fuel cell, which is capable of efficiently thermocompressing a membrane electrode assembly while suppressing thermal deformation of a frame member.SOLUTION: A manufacturing device A for a membrane electrode assembly for a fuel cell obtains a membrane electrode assembly 1 by joining a membrane electrode assembly 1 in which electrodes 3 having gas diffusion layers 31 are arranged on both sides of an electrolyte membrane 2, and a frame member 4 that is integrally joined to the outer periphery of the electrolyte membrane 2. The manufacturing device A for the membrane electrode assembly of the fuel cell includes a mold 5 having a fixed mold 52 and a movable mold 51 that is movable between a pressure-contact position and a spaced position relative to the fixed mold 52, and a moving mechanism 6 that moves the movable mold 51. The mold 5 includes heating means 7 that heats the mold 5, and humidified gas supplying means 8 that supplies humidified gas to the surface of the mold 5.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus for manufacturing a membrane electrode assembly for a fuel cell. [Background technology]

[0002] A membrane electrode assembly for a fuel cell generally has a structure in which a subgasket is disposed around the power generation section. In the process of manufacturing the membrane electrode assembly, the electrodes of the power generation section and the electrolyte membrane are generally joined by heating and pressing using a heat sink or the like (see, for example, Patent Document 1).

[0003] FIG. 7 is a schematic cross-sectional view of a main part showing a conventional manufacturing apparatus for a membrane electrode assembly for a fuel cell. 7, a conventional manufacturing apparatus A100 for a fuel cell membrane electrode assembly bonds a membrane electrode assembly 100 having electrodes 300 on both sides of an electrolyte membrane 200 to a frame member 400 bonded to the outer periphery of the electrolyte membrane 200 to obtain a membrane electrode assembly 1000. When bonding the membrane electrode assembly 100 and the frame member 400, a mold 500 consisting of an upper mold 510 and a lower mold 520 presses the membrane electrode assembly 100 and the frame member 400 together (F100), while the upper mold 510 is heated by a heating means. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-239316 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional fuel cell membrane electrode structure manufacturing apparatus A100 shown in Figure 7 had a problem in that when heating with a heating means, the frame member 400 outside the heating range was also heated by the heat H100 of the heating means, causing thermal deformation of the frame member 400.

[0006] Furthermore, the fuel cell membrane electrode structure manufacturing apparatus A100 had a problem in that, while in a standby state for the power generation unit crimping operation, the electrolyte membrane 200 would shrink due to drying caused by the radiant heat of the heated mold 500, causing deformation of the frame member 400 that had been previously bonded and connected.

[0007] Therefore, an object of the present invention is to provide a manufacturing apparatus for a membrane electrode assembly for a fuel cell that can efficiently heat and press-bond a membrane electrode assembly while suppressing thermal deformation of a frame member. [Means for solving the problem]

[0008] As a means for solving the above-mentioned problems, the present invention provides an apparatus for manufacturing a membrane electrode assembly for a fuel cell, which obtains a membrane electrode assembly by joining a membrane electrode assembly in which electrodes having gas diffusion layers are arranged on both sides of an electrolyte membrane and a frame member that is integrally joined to the outer periphery of the electrolyte membrane, the apparatus comprising: a mold having a fixed mold and a movable mold that is movable between a pressure-contact position and a separated position relative to the fixed mold; a movable mechanism that moves the movable mold; heating means that heats the mold; and humidified gas supply means that supplies humidified gas between the movable mold and the fixed mold through the mold. [Effects of the Invention]

[0009] The present invention can provide a manufacturing apparatus for a membrane electrode assembly for a fuel cell that can efficiently heat-pressure bond a membrane electrode assembly while suppressing thermal deformation of a frame member. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view showing a manufacturing apparatus for a fuel cell membrane electrode assembly according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view showing a first modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. [Figure 3] FIG. 10 is a schematic cross-sectional view showing a second modified example of the manufacturing apparatus for a fuel cell membrane electrode assembly according to an embodiment of the present invention. [Figure 4]FIG. 10 is a schematic cross-sectional view showing a third modified example of the manufacturing apparatus for a fuel cell membrane electrode assembly according to an embodiment of the present invention. [Figure 5] FIG. 10 is a schematic cross-sectional view showing a fourth modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. [Figure 6] FIG. 10 is a schematic cross-sectional view showing a fifth modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. [Figure 7] FIG. 1 is a schematic cross-sectional view showing a main part of a conventional manufacturing apparatus for a membrane electrode assembly for a fuel cell. DETAILED DESCRIPTION OF THE INVENTION

[0011] An example of a manufacturing apparatus A for a membrane electrode assembly for a fuel cell (hereinafter referred to as "manufacturing apparatus" as appropriate) according to an embodiment of the present invention will be described below with reference to FIG. In the following description, the vertically upper side of the mold 5 shown in FIG. 1 will be referred to as "top", the vertically lower side as "bottom", and the width direction as "left" and "right". Before describing the manufacturing apparatus A, the membrane electrode assembly 10 to be pressure-bonded by the manufacturing apparatus A will be described.

[0012] ≪Membrane electrode structure≫ The membrane electrode structure 10 is used in a polymer electrolyte fuel cell. The membrane electrode structure 10 is formed by joining a membrane electrode assembly 1 and a frame member 4.

[0013] <Membrane electrode assembly> The membrane electrode assembly 1 comprises an electrolyte membrane 2 and a pair of electrodes 3 joined to the upper and lower surfaces of the electrolyte membrane 2. In the membrane electrode assembly 1, the electrodes 3 are disposed on both surfaces of the electrolyte membrane 2. The membrane electrode assembly 1 has a step portion 1a formed at the joint between the constituent members of the electrode 3. In a fuel cell using the membrane electrode assembly 1, one of the pair of electrodes 3 serves as an anode and the other as a cathode.

[0014] <Electrolyte membrane> The electrolyte membrane 2 is made of a perfluorosulfonic acid polymer such as Nafion (registered trademark).

[0015] <Electrode> The electrode 3 is configured to include a porous gas diffusion layer 31 . The gas diffusion layer 31 diffuses the reaction gases (hydrogen and air) toward the electrode 3. A porous material such as carbon paper that is both electrically conductive and acid-resistant can be used as the gas diffusion layer 31. By including the gas diffusion layer 31, the electrode 3 can be pressure-bonded to the electrolyte membrane 2 in an environment where heated and humidified gas is discharged from the mold 5 and uniformly circulated, taking advantage of the gas permeability of the gas diffusion layer 31.

[0016] <Frame components> The frame member 4 is a subgasket that is integrally joined to the outer periphery of the electrolyte membrane 2. The frame member 4 is a substantially rectangular annular member that is formed along the outer periphery of the electrolyte membrane 2 so as to surround the electrolyte membrane 2. The frame member 4 is made of a sheet-like resin film.

[0017] ≪Manufacturing equipment≫ 1 is an apparatus for bonding a membrane electrode assembly 1 to a frame member 4 that is integrally bonded to the outer periphery of an electrolyte membrane 2 to obtain a membrane electrode structure 10. The manufacturing apparatus A includes a mold 5, a moving mechanism 6 that moves a movable mold 51 of the mold 5, a heating means 7, a humidified gas supplying means 8, a humidified gas discharging means 9, and a cooling means 50.

[0018] <Mold> The mold 5 is a member for applying pressure to bond the membrane electrode assembly 1 and the frame member 4. The mold 5 has a fixed mold 52 and a movable mold 51 that is movable relative to the fixed mold 52 between a pressure contact position and a separated position.

[0019] <Cushioning material> The buffer material 53 is a member for ensuring that the load F1 from the mold 5 by the movable mechanism 6 is applied uniformly to the bonding surfaces of the electrolyte 2 and the electrodes 3. The buffer material 53 is provided on the upper part of the fixed mold 52. The buffer material 53 is made of a plate-shaped cushion pad that is gas permeable and elastic. Therefore, when a pressing force is applied to the buffer material 53, it elastically deforms, thereby preventing bonding defects due to the step portion 1a of the membrane electrode assembly 1.

[0020] <Thermal insulation layer> The heat insulating layer 54 is formed between the left and right outer surfaces of the mold 5 and the cooling jig 55. The heat insulating layer 54 is formed of a heat insulating material or an air layer. By providing the heat insulating layer 54 between the left and right outer surfaces of the mold 5 and the cooling jig 55, it is possible to stabilize cooling at the interface with the heated area.

[0021] In the case of the heat insulating layer 54 made of a heat insulating material, it is formed from a plate-like member having heat insulating properties interposed between the left and right outer surfaces of the mold 5 and the cooling jig 55. The heat insulating material has gas discharge grooves formed on the upper and lower surfaces of the mold 5 to form flow paths 56 for discharging gas. In the case of the heat insulating layer 54 made of air, it is formed from a space for allowing air to flow between the left and right outer surfaces of the mold 5 and the cooling jig 55. The heat insulating material forming the space forms flow paths 56 for discharging air to the upper and lower surfaces of the mold 5.

[0022] <Cooling jig> The cooling jig 55 is a jig for forming a heat insulating layer 54 on the left and right outer surfaces of the movable mold 51 and the fixed mold 52, and for providing the cooling jig 55 with cooling means 50. The cooling jig 55 is formed of a square ring-shaped member. The cooling jig 55 presses and fixes the frame member 4 from above and below with a pressure force F2. This allows the cooling jig 55 to firmly fix and hold the frame member 4. Furthermore, the cooling jig 55 can minimize the thermal energy applied to the frame member 4, and can further suppress deformation of the frame member 4 by applying pressure and restraining it.

[0023] <Flow path> The flow path 56 is a path for supplying and discharging the heated gas from the heating means 7. The flow path 56 may also serve as a path for supplying and discharging the humidified gas from the humidified gas supply means 8. Alternatively, the flow path 56 may be provided as a separate flow path for the heated gas and a flow path for the humidified gas. Below, an example of the flow path 56 will be described, taking as an example a case where the flow path 56 serves both as a flow path for the heated gas and a flow path for the humidified gas.

[0024] As shown in Figure 1, the flow path 56 is formed from the center of the upper surface of the movable mold 51 toward the electrolyte membrane 2, and is configured so that the gas flows along the upper surface of the electrolyte membrane 2 to the cooling jig 55, and then flows between the movable mold 51 and the cooling jig 55 to the upper outside.

[0025] <Cooling means> The cooling means 50 is a cooling device for cooling (water-cooling or air-cooling) the surface of the mold 5 via a cooling jig 55. The cooling means 50 is configured to include, for example, a refrigerant generating device (not shown) for generating a refrigerant and sending it to the cooling jig 55, and a water-jacket-like refrigerant flow path (not shown) formed in the cooling jig 55. The cooling means 50 is provided at a position facing the frame member 4. Therefore, the cooling means 50 makes it possible to apply pressure while cooling the frame member 4 until it is physically restrained by applying the cooling jig 55, which has a cooling function, to the frame member 4 outside the heating and pressurizing range.

[0026] <Movable mechanism> The movable mechanism 6 is an elevating device for raising and lowering the movable mold 51 of the mold 5. The movable mechanism 6 is composed of an elevating device that raises and lowers the movable mold 51 by raising and lowering it using fluid pressure from a fluid pressure supply device such as hydraulics. The movable mechanism 6 may be any device that can raise and lower the movable mold 51, and the mechanism is not particularly limited. For example, the movable mechanism 6 may be an elevating device that raises and lowers the movable mold 51 using an electric motor device.

[0027] <Heating means> The heating means 7 is a heating device that controls the temperature of the mold 5 using heated gas. The heating means 7 is configured with a heated gas generator (not shown) that generates heated gas and sends it to a flow path 56, and a flow path 56 formed inside the mold 5 or on the outer periphery of the mold 5. The heating means 7 is preferably disposed in the movable mold 51 because a buffer material 53 is provided on the fixed mold 52, making it difficult to install the heating means 7. For this reason, a flow path 56 is formed in the movable mold 51 and between the movable mold 51 and the cooling jig 55 for the heated gas supplied from the heating means 7. The heating means 7 is provided with a flow path 56 on only one side of the mold 5 (the movable mold 51) to supply and discharge heated gas, thereby enabling the temperature of the mold 5 to be controlled with the minimum necessary configuration. The heating means 7 may be any means capable of heating the mold 5, and may be a heater.

[0028] <Humidified gas supply means> The humidified gas supplying means 8 is a humidifying device for supplying humidified gas to the surface of the mold 5. The humidified gas supplying means 8 is configured to include a humidified gas generating device (not shown) for generating humidified gas (e.g., water vapor) and sending it to the flow path 56, and the flow path 56 formed inside the mold 5 or on the outer periphery of the mold 5. The humidified gas supplying means 8 is provided at a position facing at least the electrolyte membrane 2 of the membrane electrode assembly 1, and is arranged to humidify the electrolyte membrane 2.

[0029] <Humidified gas exhaust means> The humidified gas discharge means 9 is a discharge device for discharging the humidified gas supplied to the flow path 56 in the mold 5 by the humidified gas supply means 8 from inside the mold 5. The humidified gas discharge means 9 is configured to include a humidified gas suction device (not shown) for discharging the humidified gas from the flow path 56, and the flow path 56 formed inside the mold 5 or on the outer periphery of the mold 5. The humidified gas discharge means 9 is provided at a position facing the joining position B of the membrane electrode assembly 1 and the frame member 4. The humidified gas suction device (not shown) does not have to have the humidified gas supply means 8. In other words, the humidified gas discharge means 9 can circulate the humidified gas within the flow path 56 by supplying the humidified gas into the flow path 56 using the humidified gas supply means 8. For this reason, it is sufficient to have at least the flow path 56 and either the humidified gas supply means 8 or the humidified gas discharge means 9.

[0030] As described above, the present invention shown in FIG. 1 is a manufacturing apparatus A for a membrane electrode assembly for a fuel cell, which obtains a membrane electrode assembly 10 by joining a membrane electrode assembly 1 having electrodes 3 each having a gas diffusion layer 31 arranged on both sides of an electrolyte membrane 2 with a frame member 4 integrally joined to the outer periphery of the electrolyte membrane 2, and which comprises a mold 5 having a fixed mold 52 and a movable mold 51 movable between a pressure-contact position and a spaced position relative to the fixed mold 52, and a movable mechanism 6 for moving the movable mold 51, and the mold 5 comprises a heating means 7 for heating the mold 5 and a humidified gas supply means 8 for supplying humidified gas between the movable mold 51 and the fixed mold 52 through the mold 5.

[0031] According to this configuration, the manufacturing apparatus A of the present invention includes a heating means 7 for heating the mold 5 and a humidified gas supplying means 8 for supplying humidified gas to the surface of the mold 5. Therefore, the manufacturing apparatus A can efficiently heat-pressure bond the membrane electrode structure 10 while suppressing thermal deformation of the frame member.

[0032] Furthermore, the mold 5 equipped with the humidified gas supply means 8 is provided with a humidified gas discharge means 9 for discharging the humidified gas supplied to the surface of the mold 5 to the outside of the mold 5 . According to this configuration, the humidified gas supply means 8 is provided with the humidified gas discharge means 9, thereby improving the flow of the humidified gas and enabling the electrolyte membrane 2 to be humidified efficiently.

[0033] As shown in FIG. 1, the humidified gas supply means 8 is provided at a position facing the electrolyte membrane 2 of the membrane electrode assembly 1, and the humidified gas discharge means 9 is provided at a position facing the joining position of the membrane electrode assembly 1 and the frame member 4. According to this configuration, the manufacturing apparatus A has the humidified gas supply means 8 disposed opposite the electrolyte membrane 2, and the humidified gas discharge means 9 disposed opposite the joining position of the membrane electrode assembly 1 and the frame member 4. This allows the electrolyte membrane 2 to be pressure-bonded in an appropriate humidity environment where it does not shrink.

[0034] As shown in FIG. 1, the heating means 7 and the humidified gas supplying means 8 adjust the temperature of the mold 5 and humidify the electrolyte membrane 2 of the membrane electrode assembly 1 with heated and humidified gas. According to this configuration, the heating means 7 and the humidified gas supplying means 8 can accelerate the temperature rise at the interface by the heated and humidified gas, thereby shortening the compression bonding time and facilitating adjustment of the temperature setting of the mold 5. Furthermore, since the heating means 7 and the humidified gas supplying means 8 can be integrated, space can be saved compared to when heated gas and humidified gas are supplied separately.

[0035] As shown in FIG. 1, a cooling means 50 for cooling the surface of the mold 5 is provided at a position of the mold 5 facing the frame member 4. According to this configuration, the manufacturing apparatus A has the cooling means 50, which minimizes the thermal influence of the heating means 7 and allows for temperature control at an appropriate temperature, thereby enabling efficient thermocompression bonding of the membrane electrode assembly 10 in a short time. Therefore, the cooling means 50 makes it possible to use high-performance materials that would otherwise be rejected due to poor heat resistance as candidates for the membrane electrode assembly 1 and the frame member. Furthermore, the cooling means 50 is disposed at a position facing the frame member 4, thereby enabling the membrane electrode assembly 10 to be thermocompression bonded while suppressing thermal deformation of the frame member 4. Furthermore, the cooling means 50 cools the mold 5, thereby suppressing shrinkage of the electrolyte membrane 2 due to drying caused by radiant heat from the heated mold 5.

[0036] As shown in FIG. 1, the fixed mold 52 is provided with a buffer material 53 . According to this configuration, by providing the buffer material 53 in the fixed mold 52, even if a step portion 1a is formed in the membrane electrode assembly 1, poor bonding of the constituent members of the electrode 3 due to the step portion 1a can be suppressed.

[0037] As shown in FIG. 1, the heating means 7 is disposed on the movable mold 51. According to this configuration, the heating means 7 is arranged in the movable mold 51, but not in the fixed mold 52. Therefore, the heating means 7 does not heat the buffer material 53 in the fixed mold 52, and therefore the mold 5 can be efficiently heated and the mold 5 can be efficiently installed.

[0038] [First Modification] The present invention is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the technical concept thereof. It goes without saying that the present invention also covers such modified and changed inventions. 2 is a schematic cross-sectional view showing a first modified example of the manufacturing apparatus for a fuel cell membrane electrode assembly according to an embodiment of the present invention. Hereinafter, common members in the drawings will be assigned the same reference numerals and their description will be omitted.

[0039] In the above embodiment, the flow path 56 is formed only on the movable die 51 side of the mold 5, but the present invention is not limited to this. As shown in FIG. 2, the flow channel 56 may have a flow channel 56A formed on the fixed mold 52 side in addition to the movable mold 51 side.

[0040] The flow path 56A is formed from the center of the lower surface of the fixed mold 52 toward the electrolyte membrane 2, flows along the lower surface of the electrolyte membrane 2 to the cooling jig 55, and then flows between the fixed mold 52 and the cooling jig 55 to the lower outside. By forming the flow paths 56, 56A in the mold 5 in this manner, the entire manufacturing apparatus A can be heated efficiently.

[0041] Furthermore, the buffer material 53 shown in FIG. 2 may be made of a gas-permeable cushion pad. According to this configuration, the buffer material 53 is made of a gas-permeable cushion pad, which allows the heated gas and humidified gas supplied to the mold 5 to pass through, thereby enabling efficient heating of the mold 5. Furthermore, by applying gas-permeable specifications to the buffer material 53, it is possible to supply gas to the fixed mold 52 as well, making it possible to supply gas from both the movable mold 51 and the fixed mold 52.

[0042] [Second Modification] FIG. 3 is a schematic cross-sectional view showing a second modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. 3, one gas supply flow path 56B is provided in the center, and a total of four gas discharge flow paths 56B are provided at positions corresponding to the four corners of the mold 5. This forms the flow as described above.

[0043] [Third Modification] FIG. 4 is a schematic cross-sectional view showing a third modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. Also, as shown in FIG. 4, by providing a plurality of discharge flow paths 56C not only at the four corners of the mold 5 but also at the middle portion thereof, a gas flow as shown in FIG. 4 is formed.

[0044] [Fourth Modification] FIG. 5 is a schematic cross-sectional view showing a fourth modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. 5, four gas supply flow paths 56B are arranged in a straight line at equal intervals in the center, and four gas discharge flow paths 56B are provided at each of the left and right ends of the mold 5. This forms the flow described above.

[0045] [Fifth Modification] FIG. 6 is a schematic cross-sectional view showing a fifth modified example of the manufacturing apparatus for a membrane electrode assembly for a fuel cell according to an embodiment of the present invention. 6, four gas supply flow paths 56E are arranged in a straight line at equal intervals at one end of the mold 5, and four gas discharge flow paths 56B are arranged in a straight line at equal intervals at the other end of the mold 5. This forms the flow described above. [Explanation of symbols]

[0046] 1 Membrane electrode assembly 2 Electrolyte membrane 3 electrodes 4 Frame members 5. Mold 6 Movable mechanism 7 Heating means 8 Humidified gas supply means 9 Humidified gas exhaust means 10 Membrane electrode structure 31 Gas diffusion layer 50 Cooling means 51 Movable type 52 Fixed type 53 Cushioning material A. Manufacturing equipment for membrane electrode assemblies for fuel cells (manufacturing equipment)

Claims

1. 1. A manufacturing apparatus for a membrane electrode assembly for a fuel cell, which obtains a membrane electrode assembly by joining a membrane electrode assembly in which electrodes having gas diffusion layers are disposed on both sides of an electrolyte membrane to a frame member that is integrally joined to an outer periphery of the electrolyte membrane, a mold having a fixed mold and a movable mold that is movable between a pressure-contact position and a separation position relative to the fixed mold; a moving mechanism for moving the movable mold; a heating means for heating the mold; a humidified gas supply means for supplying humidified gas between the movable mold and the fixed mold through the mold; Equipped with Manufacturing equipment for membrane electrode assemblies for fuel cells.

2. At least one of the fixed mold and the movable mold is provided with the humidified gas supply means, At least one of the fixed mold and the movable mold is provided with a humidified gas exhaust means for exhausting the humidified gas supplied between the movable mold and the fixed mold to the outside of the mold.

2. An apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 1.

3. the humidified gas supply means is provided at a position facing the electrolyte membrane of the membrane electrode assembly, the humidified gas discharge means is provided at a position facing a joining position between the membrane electrode assembly and the frame member.

3. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 2.

4. The heating means and the humidified gas supplying means adjust the temperature of the mold and humidify it with heated and humidified gas.

2. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 1.

5. a cooling means for cooling the surface of the mold is provided at a position of the mold facing the frame member; 5. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 1.

6. The fixed mold is provided with a buffer material.

5. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 1.

7. The buffer material is a gas-permeable cushion pad.

7. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 6.

8. The heating means is disposed on the movable mold.

5. The apparatus for manufacturing a membrane electrode assembly for a fuel cell according to claim 1.

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