JP5262168B2 - Manufacturing method of membrane-electrode assembly for fuel cell - Google Patents

Description

  The present invention relates to a method for producing a membrane-electrode assembly for a fuel cell.

  In a polymer electrolyte fuel cell, various methods are conventionally known as a method for producing a membrane-electrode assembly comprising an electrolyte membrane and electrodes formed on both surfaces of the electrolyte membrane. As a method for improving the bondability between the electrolyte membrane and the electrode when the electrolyte membrane and the electrode are joined by hot pressing, a method of supplying moisture to the electrolyte membrane is known. For example, a structure has been proposed in which moisture is supplied from the outside of the gas diffusion electrode laminated with the electrolyte membrane to the gas diffusion electrode when the gas diffusion electrode having a catalyst layer formed on the gas diffusion layer and the electrolyte membrane are press bonded. (For example, refer to Patent Document 1).

JP 2006-66161 A JP 2005-276599 A JP2007-173009 JP-A-8-180887

  However, if moisture is supplied to the laminate of the electrolyte membrane and the electrode, the electrolyte contained in the electrode is easily softened together with the electrolyte membrane, so that there is a problem that the electrode is easily crushed during press bonding. . Since the electrode is formed as a porous body in order to ensure gas supply to the catalyst, when the electrode is crushed, the pores of the electrode are crushed. If the pores of the electrode are crushed, the gas supply efficiency to the catalyst is reduced, and the space in the electrode is likely to be clogged with liquid water, so that the battery performance may be reduced.

  The present invention has been made in order to solve the above-described conventional problems, and when joining the electrolyte membrane and the electrode, the adhesion between the electrolyte membrane and the electrode is ensured and caused by the collapse of the electrode. The purpose is to suppress the problems that occur.

In order to achieve the above object, the present invention provides a method for producing a membrane-electrode assembly for a fuel cell, comprising:
A first step of disposing a pair of porous electrodes made of a mixture of a catalyst and an electrolyte on both surfaces of the electrolyte membrane to form a laminate including the electrolyte membrane and the electrode;
While supplying water and / or an organic solvent to only one surface of the electrolyte membrane included in the laminate, the surface on which the anode is formed , the laminate is pressurized and A second step of joining the pair of electrodes;
It is a summary to provide.

  According to the method for producing a membrane-electrode assembly for a fuel cell of the present invention configured as described above, the electrolyte membrane is pressurized while supplying water and / or an organic solvent to one surface of the electrolyte membrane. In order to join the electrode and the electrode, the electrolyte membrane is softened to improve the adhesion with each electrode, and the softening of the electrode on the other surface side can be suppressed, and the collapse of the electrode on the other surface side can be suppressed. . By increasing the adhesion, the contact resistance between the electrolyte membrane and the electrode can be suppressed, and by suppressing the collapse of the electrode on the other surface side, the gas utilization rate in this electrode is improved, while being porous It is possible to suppress clogging of the pores of the simple electrode with liquid water.

Further, with such a configuration, in the fuel cell assembled using the membrane-electrode assembly manufactured according to the present invention, as in the case of using air as the oxidizing gas while using high-purity hydrogen gas as the fuel gas. In addition, when the concentration of the electrode active material in the gas on the cathode side is lower, the effect of ensuring the gas supply to the catalyst and improving the battery performance can be obtained more remarkably.

  In the method for producing a membrane-electrode assembly for a fuel cell according to the present invention, the second step further includes a step of pressurizing the laminate against the surface of the laminate corresponding to the other surface of the electrolyte membrane. Thus, a step of supplying a dry gas may be included. With such a configuration, it is possible to positively promote the evaporation of water and / or an organic solvent in the electrode on the other side, thereby suppressing an inconvenience caused by the other electrode softening and causing the electrode to be crushed. Can be further increased.

  In the method for producing a membrane-electrode assembly for a fuel cell according to the present invention, in the first step, a gas diffusion layer that is a porous conductive member is further disposed on each of the electrodes as the laminate. Forming the laminated body, and the second step includes water from the outside of the one gas diffusion layer to one surface of the electrolyte membrane via the gas diffusion layer and the electrode. And / or a step of supplying an organic solvent may be included. With such a configuration, water and / or an organic solvent can be supplied to the electrolyte membrane via one gas diffusion layer and the electrode.

  In the method for producing a membrane-electrode assembly for a fuel cell according to the present invention, the second step includes a step of supplying vaporized water and / or an organic solvent to one surface of the electrolyte membrane. It's also good. By supplying vaporized water and / or organic solvent to one surface of the electrolyte membrane, the amount of water and / or organic solvent supplied to the electrode on one surface side can be suppressed, It is possible to suppress the surface side electrode from being excessively crushed in the pressurizing step.

  In such a method for producing a membrane-electrode assembly for a fuel cell according to the present invention, the second step includes a solvent-containing body impregnated with liquid water and / or an organic solvent, and the one surface of the laminate. It is good also as arrange | positioning on the surface of the side and including the process of heat-pressing. With such a configuration, water and / or an organic solvent impregnated by the solvent-containing body is vaporized at the time of hot pressing, and water and / or organic solvent in a vapor state is supplied from the side on which the solvent-containing body is disposed to the electrolyte. Can be supplied to the membrane.

  The present invention can be realized in various forms other than those described above. For example, a membrane-electrode assembly manufactured by the method for manufacturing a membrane-electrode assembly for a fuel cell according to the present invention, or such a membrane-electrode assembly. It can be realized in the form of a fuel cell having a body.

A. Fuel cell configuration:
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a single cell 10 constituting a fuel cell as a preferred embodiment of the present invention. The unit cell 10 includes an electrolyte membrane 20, an anode 21 and a cathode 22 that are electrodes formed on each surface of the electrolyte membrane 20, and a gas diffusion layer 23 that sandwiches the electrolyte membrane 20 on which the electrode is formed from both sides, 24 and gas separators 25 and 26 disposed further outside the gas diffusion layers 23 and 24.

  The fuel cell of this example is a solid polymer type fuel cell, and the electrolyte membrane 20 is a proton conductive ion exchange membrane formed of a solid polymer material, for example, a fluororesin having perfluorocarbon sulfonic acid. And exhibits good electrical conductivity in the wet state. The anode 21 and the cathode 22 include, for example, platinum or a platinum alloy as a catalyst. More specifically, the anode 21 and the cathode 22 include carbon particles carrying the catalyst and an electrolyte similar to the polymer electrolyte that constitutes the electrolyte membrane 20. The electrolyte membrane 20, the anode 21, and the cathode 22 constitute an MEA (membrane-electrode assembly) 30. The manufacturing process of the MEA 30 will be described in detail later.

  The gas diffusion layers 23 and 24 can be formed of a conductive member having gas permeability, such as carbon paper or carbon cloth, metal mesh, or foam metal. The gas diffusion layers 23 and 24 of the present embodiment are both formed as flat plate members. Such a gas diffusion layer 24 serves as a flow path for a gas used for an electrochemical reaction and collects current.

  The gas separators 25 and 26 are formed of a gas impermeable conductive member, for example, a member made of compressed carbon or stainless steel. Each of the gas separators 25 and 26 has a predetermined uneven shape. Due to this uneven shape, an in-cell fuel gas channel 47 through which a fuel gas containing hydrogen flows is formed between the gas separator 25 and the gas diffusion layer 23. In addition, due to the uneven shape, an in-single cell oxidizing gas channel 48 through which an oxidizing gas containing oxygen flows is formed between the gas separator 26 and the gas diffusion layer 24.

  Further, a sealing member such as a gasket is disposed on the outer peripheral portion of the single cell 10 in order to ensure gas sealing performance in the single-cell fuel gas flow channel 47 and the single-cell oxidizing gas flow channel 48 (FIG. Not shown). In addition, the fuel cell of this embodiment has a stack structure in which a plurality of single cells 10 are stacked. The outer periphery of the stack structure is parallel to the stacking direction of the single cells 10 and is fuel gas or oxidation. A plurality of gas manifolds through which gas flows are provided (not shown). The fuel gas flowing through the fuel gas supply manifold among the plurality of gas manifolds is distributed to each single cell 10 and passes through each single cell fuel gas flow channel 47 while being subjected to an electrochemical reaction. Collect in the gas exhaust manifold. Similarly, the oxidizing gas flowing through the oxidizing gas supply manifold is distributed to each single cell 10 and passes through each single cell oxidizing gas flow path 48 while being subjected to an electrochemical reaction, and then gathers in the oxidizing gas discharge manifold. To do.

B. Manufacturing method of MEA30:
FIG. 2 is a process diagram showing a method for manufacturing the MEA 30. FIG. 3 is an explanatory view schematically showing a state in the process of manufacturing the MEA 30. When manufacturing the MEA 30, first, a membrane made of a solid polymer electrolyte to be the electrolyte membrane 20 is prepared (step S100, FIG. 3A). In this embodiment, as described above, a fluorine-based polymer electrolyte membrane is used.

  Next, the catalyst ink for forming the anode 21 and the cathode 22 which are electrodes is produced (step S110). The catalyst ink contains carbon particles carrying platinum and a fluorine-based polymer electrolyte similar to the electrolyte membrane 20. For example, carbon particles comprising platinum are dispersed in a platinum compound solution (for example, a tetraammine platinum salt solution, a dinitrodiammine platinum solution, a platinum nitrate solution, or a chloroplatinic acid solution). It is produced by an impregnation method, a coprecipitation method or an ion exchange method. The platinum-supported carbon particles thus prepared are dispersed in an appropriate solvent composed of water and an organic solvent, and the catalyst ink is obtained by further mixing the electrolyte solution containing the aforementioned fluorine-based polymer electrolyte. can get.

  Next, the catalyst ink is applied on the electrolyte membrane 20 prepared in step S100, and electrodes (catalyst layers) to be the anodes 21 or the cathodes 22 are formed on both surfaces of the electrolyte membrane 20. A stacked body including a pair of electrodes is formed (step S120, FIG. 3B). The application of the catalyst ink onto the base material can be performed by, for example, a spray method, screen printing, a doctor blade method, or an ink jet method. A porous electrode having fine pores inside can be formed by drying the applied catalyst ink and evaporating the solvent while or after applying the catalyst ink as described above.

  Thereafter, the laminated body is heated and pressed in the laminating direction while supplying a solvent from the electrode side serving as the anode 21 to the laminated body formed in step S120 (step S130), thereby completing the MEA 30. In the present embodiment, a laminate in which the MEA 30 is further sandwiched between the gas diffusion layers 23 and 24 is used as the laminate to be subjected to the pressing process in Step 130. In Step S130, the outer side of the anode-side gas diffusion layer 23 is used. The solvent is supplied from Specifically, the solvent-containing body 50 containing the solvent is superimposed on the gas diffusion layer 23, and the entire laminated structure is pressed while supplying the solvent contained in the solvent-containing body 50 (FIG. 3 ( C)). Thereby, the completion of the MEA 30 and the bonding of the gas diffusion layers 23 and 24 to the laminated body are simultaneously performed.

  Here, the solvent supplied from the anode side in step S130 can be water, an organic solvent, or a mixture thereof. The organic solvent to be used only needs to have a property that makes it difficult to dissolve the polymer electrolyte included in the electrolyte membrane 20 and the electrode. As an organic solvent in which the polymer electrolyte is difficult to dissolve, an alcohol such as ethanol is particularly desirable. In this embodiment, a mixed solution of water and ethanol is used. In the case where water is used as the solvent to be supplied, the electrolyte membrane 20 becomes soft because the portion having a hydrophilic group in the polymer electrolyte absorbs water. When an organic solvent is used as the solvent to be supplied, the electrolyte membrane 20 is softened by absorbing the organic solvent by the portion having a hydrophobic group in the polymer electrolyte. As the electrolyte membrane 20 becomes soft as described above, the elastic modulus in the electrolyte membrane 20 is reduced.

  In step S130, the solvent-containing body 50 is used to supply the above-described water and / or organic solvent. As the solvent-containing body 50 for containing water and / or the organic solvent, the solvent-containing body 50 may be used during hot pressing. Various porous bodies made of a material that hardly causes a chemical reaction can be used. For example, paper such as filter paper, cloth such as nonwoven fabric, or foamable material can be used. When such a solvent-containing body 50 is placed on the gas diffusion layer 23 and heated and pressed, the liquid contained in the solvent-containing body 50 is vaporized to become vapor. Then, water and / or an organic solvent is supplied to the anode 21 and the electrolyte membrane 20 through the gas diffusion layer 23 in a vapor state.

  4 to 6 schematically show the state in the pressing process of step S130 in an enlarged manner for the electrolyte membrane 20 and the electrodes (the anode 21 and the cathode 22) including the catalyst-supporting carbon 35 and the electrolyte 37. It is explanatory drawing. FIG. 4 shows a state in which water and an organic solvent (methanol in the figure) are supplied to the electrolyte membrane 20 through the anode 21. FIG. 5 shows a state in which a laminate to which water and / or an organic solvent is supplied is hot-pressed. FIG. 6 shows a state of the MEA 30 completed by the hot press.

  As shown in FIG. 4, when vaporized water and / or organic solvent is supplied from the solvent-containing body 50, the whole polymer electrolyte constituting the anode 21 and the electrolyte membrane 20 absorbs water and / or organic solvent. And soften. When heat pressing is performed in such a state, as shown in FIG. 5, each electrode is in a state of being sunk from the surface of the softened electrolyte membrane 20 to the inner side. At this time, the anode 21 in which the polymer electrolyte as a constituent component is softened is slightly crushed by the press. At this time, the cathode 22, which is an electrode on which the solvent-containing body 50 is not disposed, has a small supply amount of water and / or organic solvent and a small degree of softening, so that it is crushed by the press compared to the anode 21. Becomes smaller. As a result, as shown in FIG. 6, each electrode sinks into the surface of the electrolyte membrane 20 to improve adhesion, and an MEA 30 in which the collapse of the cathode 22 is suppressed compared to the anode 21 is obtained.

  In step S130, the heating temperature at the time of the heating press for improving the adhesion between the electrolyte membrane 20 and the electrode can be, for example, room temperature to 300 ° C., and the heat resistant temperature of the polymer electrolyte is taken into consideration. And can be set as appropriate. The higher the temperature is, the softer the electrolyte membrane 20 becomes and it becomes easier to improve the adhesion between the electrolyte membrane 20 and the electrode. However, in this embodiment, the electrolyte membrane 20 is softened by supplying water and / or an organic solvent. It is possible to suppress the heating temperature at the time of pressing and suppress damage to the electrolyte membrane 20 due to heat. Moreover, in step S130, as a press pressure in the case of a hot press, it can be 0.01 MPa-10 MPa, for example. The higher the pressing pressure, the easier it is to improve the adhesion between the electrolyte membrane 20 and the electrode. However, in this embodiment, the adhesion is enhanced by softening the electrolyte membrane 20 by supplying water and / or an organic solvent. By suppressing the press pressure, it is possible to suppress damage to the electrolyte membrane 20 due to pressurization.

  According to the fuel cell of the present example configured as described above, when the MEA 30 is manufactured, the laminate composed of the electrolyte membrane 20 and the electrode is pressed while supplying water and / or an organic solvent. Therefore, by softening the electrolyte membrane 20 and improving the adhesion with each electrode, the internal resistance can be reduced to improve the power generation performance, and the durability of the fuel cell can be increased. That is, by supplying water and / or organic solvent from one side (anode side), water and / or organic solvent moves in the electrolyte membrane 20 to the surface of the other side (cathode side), The entire electrolyte membrane 20 is softened. By softening both surfaces of the electrolyte membrane 20 in this way, the adhesion between the electrolyte membrane 20 and both electrodes is improved during hot pressing.

  At this time, since water and / or organic solvent is supplied to the laminate only from one side (anode side), supply of water and / or organic solvent to the other side electrode (cathode 22) is suppressed. Thus, softening of the polymer electrolyte constituting the electrode on the other side is suppressed. Thus, the softening of the polymer electrolyte in the other electrode is suppressed, so that the strength of the other electrode is maintained, and the collapse of the pores of the other electrode during pressing is suppressed. be able to. By suppressing the collapse of the pores, it is possible to ensure the gas supply to the catalyst included in the electrode on the other side electrode and improve the battery performance. In this embodiment, the cathode 22 which is the electrode on the other side generates generated water along with the electrochemical reaction, but the collapse of the pores of the cathode 22 is suppressed, so that the generated water in the cathode 22 It is possible to suppress pore clogging (so-called flooding). Thereby, it becomes possible to improve the battery performance especially at the time of high load where the amount of generated water increases. In addition, the concentration of the electrode active material in the gas supplied to the electrode on the other side is lower as in the case where high purity hydrogen gas is used as the fuel gas supplied to the fuel cell and air is used as the oxidizing gas. In this case, by suppressing the collapse of the pores on the electrode on the other side, the effect of ensuring the gas supply to the catalyst and improving the battery performance can be obtained more remarkably.

  As in this embodiment, when the electrode is formed by applying a catalyst ink on the electrolyte membrane 20 and then heated and pressed again, the effect of further improving the adhesion between the electrolyte membrane 20 and the electrode is obtained. In addition, it is possible to obtain the effect of making the electrodes thin by making the pore sizes uniform. When the catalyst ink is dried to form a porous electrode, there is a large variation in the size of the pores formed in the interior. This may cause a problem that the path when moving becomes longer and the internal resistance becomes larger. By pressing an electrode formed by drying such a catalyst ink, too large pores are crushed and the size of the pores is made uniform, and the entire electrode is thinned. As a result, the path of electrons and protons is shortened, the internal resistance is reduced, and the distance over which the gas diffuses in the electrode is shortened, so that the gas utilization efficiency at the electrode is improved. At this time, in the present embodiment, the above-described effects can be obtained by suppressing excessive crushing of the cathode 22.

  FIG. 7 is an explanatory diagram showing the results of confirming the performance of the fuel cell including the MEA 30 manufactured by the same MEA manufacturing method as in this example. Here, a fuel cell (single cell) is assembled using each of the MEA of the example and the MEA of the comparative example, and the output current value (current density in FIG. 7) is changed while supplying a large excess of hydrogen and air. The result (VI characteristic) which investigated the change of the output voltage value at the time is shown.

  In producing the MEA of the example, in step S100, an ion exchange membrane having a thickness of 30 μm made of a polymer having a sulfonic acid group was prepared as the electrolyte membrane 20. In step S110, platinum-supported carbon particles having a platinum support amount of 60 wt%, an electrolyte solution containing a fluorine-based polymer electrolyte (Nafion solution, manufactured by Aldrich), and water having a mixing ratio of 1: 1; A catalyst ink was prepared by mixing with a solvent composed of ethanol. Thereafter, in step S120, electrodes were formed by spraying on both surfaces of the electrolyte membrane 20 using the catalyst ink. Note that, after the step of applying the catalyst ink on the electrolyte membrane 20, a drying step is further performed to vaporize the solvent in the catalyst ink and make the electrode porous.

Thereafter, in step S130, a gas diffusion layer made of carbon paper was further laminated on each electrode, and a heat press was performed. At that time, a filter paper containing a mixture of water and ethanol in a ratio of 1: 1 at a ratio of 1 mg / cm ² is disposed between the electrode serving as the anode 21 and the press panel of the press. The hot pressing was performed in a state where steam mixed with water and ethanol was supplied only from the anode side. At this time, the heating temperature was 140 ° C., the pressing pressure was 3 MPa, and pressing was performed for 4 minutes.

The MEA of the comparative example was manufactured in the same manner as the MEA of the above example except for the configuration related to the solvent supply at the time of pressing in step S130. That is, in the MEA of the comparative example, in step S130, the filter paper containing a mixture of water and ethanol at a ratio of 1: 1 at a ratio of 1 mg / cm ² is combined with the gas diffusion layer on the anode side and the cathode side. It was also placed on the gas diffusion layer and heated and pressed.

  As shown in FIG. 7, the fuel cell including the MEA of the example provides a higher output voltage over the entire output current value than the fuel cell including the MEA of the comparative example, and in particular, the output current value is large. This effect was remarkably obtained.

C. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

C1. Modification 1 (Method for forming electrodes):
In the embodiment, the electrode is formed by applying the catalyst ink on the electrolyte membrane 20, but a different configuration may be used. For example, the MEA 30 is manufactured by applying the catalyst ink on the gas diffusion layers 23 and 24 to form electrodes, pressing the electrode formation surfaces of the gas diffusion layers 23 and 24 and the electrolyte membrane 20 and pressing them. Also good. In this case, in the manufacturing process similar to that shown in FIG. 2, a process of applying the catalyst ink on the gas diffusion layers 23 and 24 may be performed instead of step S120. Then, as shown in FIG. 3C, the solvent-containing body 50 may be disposed on the gas diffusion layer 23 on the anode side and heated and pressed.

  Alternatively, instead of step S120, a process may be performed in which an electrode is formed on a predetermined substrate separately from the electrolyte film 20 using catalyst ink, and the formed electrode is thermally transferred onto the electrolyte film 20. . In this case, for example, a substrate made of polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyethylene naphthalate (PEN) or polyethylene (PE) is used as the substrate to be removed after the thermal transfer of the electrode. Can do.

C2. Modification 2 (solvent supply method):
In the embodiment, the solvent supply body 50 such as a filter paper impregnated with a liquid composed of water and / or an organic solvent is disposed to supply the solvent to the surface on the anode side of the electrolyte membrane 20. good. For example, in the press used in the pressing step in step S130, a steam supply device for ejecting the above-described water and / or organic solvent from the surface of the pressure plate on the anode side is provided, and while pressing the laminate, It is good also as a structure which sprays a vapor | steam directly with respect to a press surface. In addition, when performing the press for improving the adhesion of the electrode while supplying the vapor in this way, only the MEA 30 is pressed without disposing the gas diffusion layer, and after the press accompanied with the supply of the vapor, separately. The gas diffusion layer may be joined.

  Further, as a method of supplying water and / or an organic solvent only to one side of the electrolyte membrane 20, a method of supplying from the outside of one electrode (the anode 21 in the embodiment) via this one electrode is used. Then, it may be supplied directly to the interface between the electrolyte membrane 20 and the one electrode. Specifically, for example, when the electrolyte membrane 20 and an electrode formed separately from the electrolyte membrane 20 are joined, water and / or the surface of the electrolyte membrane 20 to which the one electrode is joined. It is good also as spraying the vapor | steam of an organic solvent. Alternatively, prior to bonding with the electrode, the solvent may be supplied in a liquid state to the bonding surface of the electrolyte membrane 20 with the one electrode in advance by, for example, spraying.

C3. Modification 3 (Method for suppressing softening of the other electrode):
In the examples, during the heat pressing of the laminate, the solvent is supplied only from one side to suppress the softening and crushing of the electrode arranged on the other side. It is good also as suppressing supply of a solvent and suppressing softening of the other electrode. FIG. 8 is an explanatory view showing an example of a method for manufacturing the MEA 30 as such a modification. FIG. 8 shows a state in which a laminated body in which the gas diffusion layers 23 and 24 are arranged on the electrolyte membrane 20 together with the anode 21 and the cathode 22 is pressed as in FIG. 3C. Here, instead of the arrangement of the solvent-containing body 50 on the anode side, a vapor supply device for ejecting water and / or organic solvent vapor from the pressure plate on the anode side of the press machine is provided, and the anode of the electrolyte membrane 20 is provided. The solvent is supplied to the side. Such a steam supply device includes a steam outlet 51 formed over the entire contact surface with the laminate in the anode-side pressure plate, a steam generator (not shown) such as a bubbler, and the anode-side pressure plate. And a steam flow path 52 that connects the steam generator and the steam outlet.

  Further, in FIG. 8, a dry gas supply device is provided for ejecting dry gas from a pressurizing plate on the cathode side of the press machine. As the dry gas, various gases can be used as long as the gas can be kept dry so that the cathode 22 can be prevented from being softened by being supplied to the cathode side. As such a dry gas, for example, pressurized air can be used. As shown in FIG. 8, the dry gas supply device includes a dry gas jet 53 formed over the entire contact surface with the laminated body in the cathode-side pressurizing plate, and a cathode-side additive that communicates with the dry gas jet. A dry gas channel 54 formed in the platen and a dry gas supply unit (not shown) such as a blower for feeding the dry gas into the dry gas channel can be configured.

  With such a configuration, by actively promoting the evaporation of the solvent in the other electrode, it is possible to further enhance the effect of suppressing inconvenience due to the other electrode softening and causing the electrode to collapse. .

C4. Modification 4:
Different types of polymer electrolytes may be used for the electrolyte membrane and the electrode. For example, the electrolyte membrane is made of a hydrocarbon-based polymer electrolyte, and the same fluorine-based electrolyte as in the embodiment can be used as the polymer electrolyte included in the electrode. Even in such a case, by supplying the solvent only from one side of the electrolyte membrane, it is possible to achieve both the improvement of the adhesion between the electrolyte membrane and the electrode and the suppression of the collapse of the electrode on the other side. Similar effects can be obtained.

2 is a schematic cross-sectional view illustrating a schematic configuration of a single cell 10. FIG. 5 is a process diagram illustrating a method for manufacturing MEA 30. FIG. It is explanatory drawing which represents typically the mode in the middle of the process of manufacturing MEA30. It is explanatory drawing showing the state in the middle in step S130. It is explanatory drawing showing the state in the middle in step S130. It is explanatory drawing showing the state in the middle in step S130. It is a figure which shows the result of having confirmed the performance of the fuel cell provided with MEA30. It is explanatory drawing showing the manufacturing method of MEA30 as a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Single cell 20 ... Electrolyte membrane 21 ... Anode 22 ... Cathode 23, 24 ... Gas diffusion layer 25, 26 ... Gas separator 30 ... MEA
35 ... Catalyst-supporting carbon 37 ... Electrolyte 47 ... Fuel gas flow path in single cell 48 ... Oxidation gas flow path in single cell 50 ... Solvent-containing body 51 ... Steam outlet 52 ... Steam passage 53 ... Dry gas outlet 54 ... Dry Gas flow path

Claims (5)

A method for producing a membrane-electrode assembly for a fuel cell, comprising:
A first step of disposing a pair of porous electrodes made of a mixture of a catalyst and an electrolyte on both surfaces of the electrolyte membrane to form a laminate including the electrolyte membrane and the electrode;
While supplying water and / or an organic solvent to only one surface of the electrolyte membrane included in the laminate, the surface on which the anode is formed, the laminate is pressurized and A second step of joining the pair of electrodes;
A method for producing a membrane-electrode assembly for a fuel cell. A method for producing a membrane-electrode assembly for a fuel cell according to claim 1,
The second step further includes a step of supplying a dry gas to the surface of the laminate corresponding to the other surface of the electrolyte membrane when the laminate is pressurized. Manufacturing method of joined body. A method for producing a membrane-electrode assembly for a fuel cell according to claim 1 or 2,
The first step includes a step of forming a laminate in which a gas diffusion layer, which is a porous conductive member, is further disposed on each of the electrodes as the laminate.
The second step includes a step of supplying water and / or an organic solvent from one outside of the gas diffusion layer to one surface of the electrolyte membrane via the gas diffusion layer and the electrode. A method for producing a membrane-electrode assembly for a fuel cell. A method for producing a membrane-electrode assembly for a fuel cell according to any one of claims 1 to 3,
The second step includes a step of supplying vaporized water and / or an organic solvent to one surface of the electrolyte membrane. A method for producing a membrane-electrode assembly for a fuel cell. A method for producing a membrane-electrode assembly for a fuel cell according to claim 4,
The second step includes a step of placing a solvent-containing body impregnated with liquid water and / or an organic solvent on the surface on the one surface side of the laminate and heat-pressing the fuel cell membrane -Manufacturing method of electrode assembly.

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