JP2007103122A - Manufacturing method of electrode and electrode manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deterioration of an electrolyte membrane and an electrode catalyst material in a fixing process. <P>SOLUTION: The electrode manufacturing device is provided with a transferring part and a fixing part. In the transferring part, an image (an electrode catalyst layer) of an electrode catalyst material developed on a surface of a photoconductor drum is transferred on an electrolyte membrane. In a fixing part, the transferred electrode catalyst layer is fixed to the electrolyte membrane. Specifically, the electrolyte membrane and the electrode catalyst material are heated and pressed by a heated fixing roller and moreover, high temperature steam is sprayed from inside of the fixing roller. The electrode catalyst material is uniformly heated by high temperature steam and softening of the resin composition is apt to occur. Due to the softening of the resin composition of the electrode catalyst material, a high adhesiveness can be obtained even by a weak pressure, and sure fixation can be realized and deterioration of the electrolyte membrane and the electrode catalyst material can be prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrode manufacturing method and an electrode manufacturing apparatus for a fuel cell in which a powdered electrode catalyst material is adhered to the surface of a fuel cell electrolyte membrane and then the electrode catalyst material is fixed to the fuel cell electrolyte membrane.

  A solid polymer electrolyte fuel cell includes a membrane-electrode assembly (MEA: Membrane-) composed of an electrolyte membrane composed of an ion exchange membrane, an anode disposed on one surface of the electrolyte membrane, and a cathode disposed on the other surface of the electrolyte membrane. A cell stack including a plurality of Electrode Assemblies) and a separator that forms a fluid flow path for supplying fuel gas (hydrogen) and oxidizing gas (oxygen, usually air) to the anode and cathode is provided. The anode and cathode have a catalyst layer facing the electrolyte membrane, and a diffusion layer is provided between the catalyst layer and the separator. In a solid polymer electrolyte fuel cell, hydrogen gas is ionized on the anode side, the hydrogen ions move through the electrolyte membrane to the cathode side, and on the cathode side, a reaction that generates water from oxygen, hydrogen ions, and electrons is performed. Is called.

  Generally, in the manufacturing process of the fuel cell, the catalyst layer is formed by applying an electrode catalyst material to both surfaces of the electrolyte membrane or one surface of the diffusion layer. Various methods for applying the electrode catalyst material have been proposed. For example, an electric charge is applied to a powdered electrode catalyst material (electrode catalyst), the charged electrode catalyst material is electrostatically attached to a photosensitive drum charged in a predetermined pattern, and further, the electrode on the electrostatic drum is electrostatically attached. A method of transferring and fixing a catalyst material on the surface of an electrolyte membrane for fuel cells (a membrane for fuel cells) is known (for example, Patent Document 1). In this case, the fixing of the electrode catalyst material is realized by heating and pressurizing the fuel cell electrolyte membrane to which the electrode catalyst material is adhered and the electrode catalyst material. By heating, the electrode catalyst material is softened and is easily fixed to the electrolyte membrane even at a relatively low pressure.

Japanese Patent Laid-Open No. 2004-139846

  However, in the conventional method, the electrode catalyst material is heated by heating a pressure roller that presses the fuel cell electrolyte membrane. In this case, the portion in contact with the pressing roller is efficiently heated, but the portion not in contact with the pressing roller is hardly heated. Therefore, it is difficult for the electrode catalyst material to be softened, and it is necessary to increase the pressure. However, when the applied pressure is increased, there is a problem in that the electrode catalyst material is deteriorated and the fuel cell electrolyte membrane is deteriorated due to the electrode catalyst material biting into the fuel cell electrolyte membrane. In order to solve this problem, it is conceivable that the temperature of the pressure roller is increased to efficiently heat the portion not in contact with the pressure roller to promote efficient softening of the electrode catalyst material. However, in this case, the portion in contact with the pressing roller is excessively heated, and again, the electrode catalyst material and the fuel cell electrolyte membrane are deteriorated.

  Therefore, an object of the present invention is to provide an electrode manufacturing method that can further improve the quality of a fuel cell. In particular, it is an object to prevent quality deterioration of the electrode catalyst material and the fuel cell electrolyte membrane in the fixing stage of the electrode catalyst material.

  The electrode manufacturing method of the present invention is a method for manufacturing a fuel cell electrode in which a powdered electrode catalyst material is adhered to the surface of a fuel cell electrolyte membrane, and then the electrode catalyst material is fixed to the fuel cell electrolyte membrane. An adhesion step of depositing an electrode catalyst material on the adhesion surface of the fuel cell electrolyte membrane; spraying high temperature steam toward the adhesion surface; and pressurizing the fuel cell electrolyte membrane to apply the electrode catalyst material to the fuel cell And a fixing step of fixing to the electrolyte membrane.

  In a preferred embodiment, the high-temperature steam is sprayed from the inside of the pressurizing body that pressurizes the fuel cell electrolyte membrane. In this case, it is desirable that the pressurizing surface of the pressurizing body is made of a hard material in which a plurality of holes through which high-temperature steam passes from the inside of the pressurizing body to the outside are uniformly formed. Further, it is desirable that the pressurizing body incorporates an overheating means capable of adjusting the temperature for heating the fluid supplied from the outside to generate high-temperature steam.

  In another preferred embodiment, the high temperature steam is sprayed immediately before being pressurized by the pressurized body.

  It is desirable that the temperature of the high-temperature steam can be adjusted. The pressurizing body is preferably pressed at a temperature and pressure that do not deteriorate the electrolyte membrane for fuel cells and the electrode catalyst material. Specifically, it is desirable that the pressurized body heats and pressurizes the fuel cell electrolyte membrane at a temperature of about 140 ° C. or less and a pressure of about 20 kgf / cm or less.

  In addition, the high-temperature steam is desirably a temperature that does not deteriorate the electrolyte membrane for a fuel cell and the electrode catalyst material and softens the electrode catalyst material. Specifically, the high temperature steam is desirably at a temperature of about 100 ° C to 200 ° C.

  Another electrode manufacturing apparatus according to the present invention is a fuel cell electrode manufacturing apparatus in which a powdered electrode catalyst material is attached to the surface of a fuel cell electrolyte membrane and then the electrode catalyst material is fixed to the fuel cell electrolyte membrane. An adhesion means for adhering the electrode catalyst material to the adhesion surface of the fuel cell electrolyte membrane, and a fixing means for fixing the adhered electrode catalyst material to the fuel cell electrolyte membrane. Spraying means for spraying high temperature steam toward the electrocatalyst material formed, and pressurizing means for pressurizing the electrolyte membrane for fuel cells.

  According to the present invention, when the electrode catalyst material is fixed, the high temperature steam is sprayed, so that the electrode catalyst material is heated evenly and the surface of the electrode catalyst material is easily softened. As a result, stable fixing can be realized while preventing deterioration of the electrode catalyst material and the fuel cell electrolyte membrane. As a result, a higher quality fuel cell can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. First, the solid polymer electrolyte fuel cell 10 (hereinafter abbreviated as “fuel cell 10”) will be briefly described. FIG. 1 is a cross-sectional view showing a schematic configuration of the fuel cell 10. The fuel cell 10 includes a membrane-electrode assembly including an electrolyte membrane 12 made of an ion exchange membrane, an anode 14 (electrode) stacked on one surface, and a cathode 16 (electrode) stacked on the other surface. ing. Each membrane-electrode assembly is supported by a separator 22 that forms a fuel gas flow path 26 in the anode 14 and the cathode 16 to form a cell. The separator 22 is also formed with a refrigerant flow path 24 through which a refrigerant (usually cooling water) for cooling the cells flows. A plurality of cells are stacked to form a cell stack to form the fuel cell 10. On the anode 14 side, hydrogen gas is ionized, and the hydrogen ions pass through the electrolyte membrane 12 and move to the cathode 16 side. On the cathode 16 side, water is generated in response to the moving hydrogen ions, oxygen and electrons.

  The anode 14 and the cathode 16 are composed of an electrode catalyst layer 20 and a diffusion layer 18. The diffusion layer 18 is a layer having both air permeability and conductivity, and is disposed between the separator 22 and the electrode catalyst layer 20. The electrode catalyst layer 20 is made of carbon powder (electrode catalyst material) carrying a catalyst noble metal (for example, Pt) and has conductivity. The electrode catalyst layer 20 is disposed on both sides of the electrolyte membrane 12 so as to hold the electrolyte membrane 12. The electrode catalyst layer 20 is formed by applying an electrode catalyst material on both surfaces of the electrolyte membrane 12 or by applying an electrode catalyst material on one surface of the diffusion layer 18.

  FIG. 2 is a schematic configuration diagram of an electrode manufacturing apparatus 30 according to the embodiment of the present invention. The electrode manufacturing apparatus 30 is an apparatus for forming the electrode catalyst layer 20 by applying a powdered electrode catalyst material to the electrolyte membrane 12 (or the diffusion layer 18).

  The electrode manufacturing apparatus 30 transfers and fixes the powdered electrode catalyst material 50 onto the surface of the electrolyte membrane 12 while sequentially feeding the electrolyte membrane 12 formed in a sheet shape downstream. The electrolyte membrane 12 is a thin film such as a perfluorosulfonic acid film, and is transported from the upstream side (left side in FIG. 2) to the downstream side (right side in FIG. 2) by various transport means. In FIG. 2, a conveying unit including a driving roller 38 and a driven roller 36 is illustrated as an example of the conveying unit. In this conveying means, the driving roller 38 is provided on the downstream side, and the driven roller 36 is provided on the upstream side. The electrolyte film 12 after the electrode catalyst material 50 is transferred and fixed is wound around the driving roller 38, and the electrolyte film 12 before the transfer and fixing is wound around the driven roller 36. When the driving roller 38 rotates and winds up the electrolyte membrane 12, the driven roller 36 is driven in conjunction with the winding operation to send the electrolyte membrane 12 before transfer / fixing of the electrode catalyst material 50 downstream. .

  A transfer unit 32 and a fixing unit 34 are provided between the driven roller 36 and the driving roller 38. In the transfer part 32, the powdered electrode catalyst material 50 is transferred to the surface of the electrolyte membrane 12 by electrostatic force. In the fixing unit 34, the electrolyte membrane 12 to which the electrode catalyst material 50 has been transferred is heated and pressurized to fix the electrode catalyst material 50.

  The transfer unit 32 is provided with a photosensitive drum 40 for transferring the electrode catalyst material 50. The photosensitive drum 40 is a rotating body in which at least a surface layer is covered with a material such as amorphous silicon or amorphous selenium. The photosensitive drum 40 is arranged so as to be close to the upper surface of the electrolyte membrane 12 to be conveyed sequentially and so that its axis is perpendicular to the conveyance direction of the electrolyte membrane 12. The driving of the photosensitive drum 40 is controlled by a control unit (not shown), and is driven to rotate at a peripheral speed synchronized with the conveying speed of the electrolyte membrane 12. A pressure contact roller is provided at a position facing the photosensitive drum 40, and the electrolyte membrane 12 is held and conveyed in cooperation with the photosensitive drum 40. This pressure contact roller is also driven and controlled by the control means, and is driven to rotate at the conveying speed of the electrolyte membrane 12 and the peripheral speed that is motivated.

  A charging roller 42 is provided in the vicinity of the photosensitive drum 40. The charging roller 42 is controlled by a control unit (not shown), and charges the photosensitive drum 40 by applying a voltage in which alternating current and direct current are superimposed. FIG. 2 illustrates a case where the photosensitive drum 40 is positively charged. A light projecting device 44 is provided on the downstream side of the photosensitive drum 40 from the charging roller 42. The light projecting device 44 has the same configuration and function as a conventionally known electrostatic copying machine, and can neutralize the projected area. The light projecting device 44 projects light on a predetermined area on the surface of the photosensitive drum 40 in accordance with an instruction from the control unit, and discharges only the predetermined area. As a result, an electrostatic latent image charged in a predetermined pattern is formed on the surface of the photosensitive drum 40.

  On the further downstream side of the photosensitive drum 40 than the charging roller 42, a housing 46 that houses the electrode catalyst material 50 is provided. A discharge port 48 for discharging the electrode catalyst material 50 is provided in the container 46 at a position close to the photosensitive drum 40. The electrode catalyst material charged by the electrostatic application electrode 56 flies to the surface of the photosensitive drum 40 through the discharge port 48.

  The developing roller 52 is disposed in the vicinity of the photosensitive drum 40 inside the container 46. The developing roller 52 is driven to rotate at substantially the same speed as the photosensitive drum 40 in accordance with an instruction from a control unit (not shown). The developing roller 52 is conductive, but its surface is covered with an insulating film such as polytetrafluoroethylene or silicon.

  The developing roller 52 is connected to the positive pole of the charge supply power source 58 and the surface thereof is charged. On the other hand, the negative pole of the charge supply power source 58 is connected to the electrostatic application electrode 56. The electrostatic application electrode 56 is a conductor provided inside the container 46, and negatively charges the powdered electrode catalyst material 50 accommodated in the container 46.

  The electrocatalyst material 50 charged negatively adheres uniformly to the surface of the developing roller 52 charged positively. The electrode catalyst material 50 attached to the developing roller 52 moves to the vicinity of the photosensitive drum 40 as the developing roller 52 rotates. Since the photosensitive drum 40 is positively charged, the electrode catalyst material 50 (negatively charged) moved to the vicinity of the photosensitive drum 40 flies to the photosensitive drum 40 (an electrostatic latent image thereof) by Coulomb force. ,Adhere to. As a result, an image (electrode catalyst layer 20) of a predetermined pattern is formed on the surface of the photosensitive drum 40 by the electrode catalyst material 50. The formed electrode catalyst layer 20 (image) contacts the electrolyte membrane 12 being conveyed along with the rotation of the photosensitive drum 40 and is transferred to the surface of the electrolyte membrane 12.

  The fixing unit 34 is provided on the downstream side of the transfer unit 32, and fixes the electrode catalyst layer 20 transferred to the electrolyte membrane 12 to the electrolyte membrane 12. FIG. 3 is a diagram illustrating a configuration of the fixing unit 34. The fixing unit 34 includes a fixing roller 60 that heats and pressurizes the electrolyte membrane 12, and a counter roller 62 that is disposed to face the fixing roller 60. The fixing roller 60 is arranged so as to be close to the upper surface of the electrolyte membrane 12 to which the electrode catalyst material 50 has been transferred, and so that its axis is perpendicular to the transport direction of the electrolyte membrane 12. The facing roller 62 is provided at a position facing the fixing roller 60, and holds the electrolyte membrane 12 in cooperation with the fixing roller 60.

  The outer surface of the facing roller 62 is made of an elastic material such as sponge or rubber. By forming the outer surface of the opposing roller 62 with an elastic material, the contact property between the electrolyte membrane 12 and the fixing roller 60 and the opposing roller 62 can be enhanced. Further, since the excessive pressure can be removed by elastic deformation of the elastic material, it is possible to pressurize the electrolyte membrane 12 with an appropriate pressure.

  The fixing roller 60 is a hollow substantially cylindrical member, and is a rotating body that is rotationally driven in accordance with an instruction from the control means. The outer surface of the fixing roller 60 is made of a porous member 64. The porous member 64 is made of a material having high heat resistance and high heat conductivity, such as a metal material, and a large number of through holes 64a are formed uniformly. By configuring the outer surface of the fixing roller 60 with the porous member 64, high-temperature steam 70 described later can be sprayed from the inside of the fixing roller 60 to the outside. A heater (not shown) is connected to the porous member 64 (that is, the outer surface of the fixing roller 60), and the temperature can be adjusted as appropriate. Further, the rotation shaft 66 of the fixing roller 60 is connected to a vertical movement mechanism (not shown), and the height thereof can be changed as appropriate. By changing the height of the rotating shaft 66, the pressure applied to the electrolyte membrane 12 can be appropriately adjusted.

  High temperature steam 70 is sprayed from the inside of the fixing roller 60. The high-temperature steam 70 may be generated outside the fixing roller 60 and then enclosed in the fixing roller 60, or may be generated inside the fixing roller 60. However, in any case, it is desirable that a mechanism capable of adjusting the amount and temperature of the high-temperature steam 70 is provided. In the present embodiment, high-temperature steam 70 is generated inside the fixing roller 60. The internal configuration of the fixing roller 60 in this case will be briefly described. Inside the fixing roller 60, a fluid supply path 68 for supplying a fluid that is a raw material of the high-temperature steam 70 such as water, and a heater 65 that heats the fluid and converts it into steam are provided.

  The fluid supply path 68 is a pipe or the like inserted from the outside into the fixing roller 60, and fluid (for example, water or water vapor) is supplied into the fixing roller 60 through the fluid supply path 68. This fluid path is preferably made of a material having heat resistance to such an extent that the high-temperature steam 70 does not deform the shape.

  The heater 65 heats the supplied fluid and changes it to high-temperature steam 70. It is desirable that the heater 65 has a heating capability sufficient to generate steam at a sufficiently high temperature (for example, 100 ° C. to 200 ° C.). Further, it is desirable that the temperature of the high-temperature steam 70 generated by appropriately changing the heating temperature can be adjusted. Further, the heater 65 may be single, but a plurality of heaters 65 is more desirable. By using a plurality of heaters 65, the inside of the fixing roller 60 can be heated uniformly, and as a result, the high-temperature steam 70 having a constant temperature can be generated regardless of the location. The generated high-temperature steam 70 fills the internal space of the fixing roller 60 and is then sprayed to the outside through a through hole 64 a formed on the outer surface of the fixing roller 60.

  Here, as described above, the fixing roller 60 contacts and pressurizes the electrolyte membrane 12 to which the electrode catalyst layer 20 has been transferred. Therefore, the electrolyte membrane 12 to which the electrode catalyst layer 20 has been transferred receives the high-temperature steam 70 sprayed from the inside of the fixing roller 60. The spraying of the high-temperature steam 70 can stably fix the electrode catalyst layer 20 while improving the quality of the electrode catalyst layer 20 and the electrolyte membrane 12. This will be described in detail below.

  FIG. 4 is an image diagram showing the state of the electrolyte membrane 12 before the electrode catalyst layer 20 is transferred and fixed. FIG. 3 is a conceptual diagram showing the state of the electrolyte membrane 12 in which the electrode catalyst layer 20 has been satisfactorily fixed, and FIG. 4 is a conceptual diagram showing the state of the electrolyte membrane 12 in which the fixing failure has occurred.

  As described above, the electrode catalyst layer 20 is a powder of the electrode catalyst material 50 in which the catalytic noble metal 50b such as Pt is supported by the carbon 50a. In addition, a resin component is mixed in the powder of the electrode catalyst material 50 in order to improve the adhesion between the electrode catalyst materials 50 and between the electrolyte membrane 12 and the electrode catalyst material 50. Immediately after the transfer, the electrode catalyst material 50 is only evenly adhered to the upper surface of the electrolyte membrane 12, and the adhesion between the electrode catalyst materials 50 and between the electrolyte membrane 12 and the electrode catalyst material 50 is small.

  Conventionally, in order to fix the electrode catalyst material 50 to the electrolyte membrane 12, the electrode catalyst material 50 is heated and pressurized by a heated fixing roller 60. The surface of the electrode catalyst material 50 is softened by heating, and is brought into close contact with the electrolyte membrane 12 by pressurization (20 kgf / cm to 200 kgf / cm). As shown in FIG. 5, the electrocatalyst material 50 that is well fixed by appropriate heating and pressurization spreads evenly on the upper surface of the electrolyte membrane 12 and adheres closely to the electrolyte membrane 12.

  However, in the conventional heating and pressurization by the heated fixing roller 60, proper heating and pressurization are difficult, and fixing failure often occurs. For example, when the surface of the electrode catalyst material 50 is pressurized with an excessive pressure before being softened, the electrode catalyst material 50 may bite into the electrolyte membrane 12 and deteriorate the electrolyte membrane 12 as shown in FIG. . Conversely, if the applied pressure is too small and the electrode catalyst material 50 does not adhere to the electrolyte membrane 12, there arises a problem that the electrode catalyst material 50 falls off from the electrolyte membrane 12. The heating temperature is also closely related to the fixing failure due to the inappropriate pressurizing force. When heated to an appropriate temperature, the surface of the electrode catalyst material 50, more specifically, the resin component on the surface of the electrode catalyst material 50 is softened, and the electrode catalyst materials 50, the electrode catalyst material 50 and the electrolyte are softened. Adhesiveness with the film 12 is improved. However, if the heating is insufficient and the resin component of the electrode catalyst material 50 is not sufficiently softened, sufficient adhesiveness cannot be obtained, and the above-described problems of biting in and dropping off occur. Therefore, proper heating was essential for good fixing.

  However, in the conventional method in which the electrode catalyst material 50 is heated by heating the fixing roller 60, appropriate heating is difficult. This will be described with reference to FIG. FIG. 7 is an image diagram showing the temperature distribution of the electrode catalyst material 50 in the conventional fixing method. In FIG. 7, the higher the temperature, the darker the color. In addition, the electrode catalyst material 50 is illustrated in a spherical shape for ease of viewing.

  Conventionally, the electrode catalyst material 50 is heated by heating the fixing roller 60 to a high temperature (about 80 ° C. to 200 ° C.). Therefore, a portion of the electrode catalyst material 50 that is in contact with the fixing roller 60 becomes high temperature. However, heat is not easily transmitted to a portion that is not in direct contact with the fixing roller 60, and as a result, the temperature does not rise to an appropriate temperature. As a result, sufficient adhesiveness could not be obtained, and biting and dropping as described above occurred. Of course, by raising the temperature of the fixing roller 60, it is possible to set the portion away from the fixing roller 60 to an appropriate temperature. However, in this case, the temperature of the portion that is in direct contact with the fixing roller 60 becomes too high, and there is a problem that the catalyst powder deteriorates due to the heat.

  Therefore, in this embodiment, the high temperature steam 70 is sprayed from the inside of the fixing roller 60 to uniformly heat the electrode catalyst material 50 to an appropriate temperature. This will be described with reference to FIG. FIG. 8 is an image diagram showing the temperature distribution of the electrode catalyst material 50 in the present embodiment. Also in FIG. 8, the higher the temperature, the darker the color.

  In the case of this embodiment, high-temperature steam 70 is sprayed from the inside of the fixing roller 60. The high temperature steam 70 is a fluid and can spread all around the electrocatalyst material 50. Therefore, the electrode catalyst material 50 is surrounded by the high temperature steam 70. The electrocatalyst material 50 surrounded by the high temperature steam 70 is heated evenly. The same applies to the electrode catalyst material 50 that is not in direct contact with the fixing roller 60. As a result, the surface of the electrode catalyst material 50 is easily softened. Further, unlike the heat generated from the fixing roller 60, the high-temperature steam 70 can spread over a wide range.

  That is, as in this embodiment, the electrode catalyst material 50 can be heated uniformly by spraying the high-temperature steam 70. Therefore, the resin component of the electrode catalyst material 50 is easily softened, and the electrode catalyst material 50 can be fixed to the electrolyte membrane 12 even with a relatively small applied pressure. As a result, the electrode catalyst material 50 can be satisfactorily fixed without biting or dropping off.

  In the present embodiment, the electrode catalyst material 50 is heated by the high temperature steam 70. Accordingly, the fixing roller 60 may be at a relatively low temperature (for example, 60 ° C. to 140 ° C.). By lowering the fixing roller 60 at a low temperature, the electrode catalyst material 50 and the electrolyte membrane 12 can be prevented from being deteriorated by heat, and a higher quality electrode can be obtained.

  Next, the flow of electrode manufacturing in the electrode manufacturing apparatus 30 will be briefly described. When manufacturing an electrode, the powdered electrode catalyst material 50 is put into the container 46 of the transfer unit 32 in advance. Further, the electrolyte membrane 12 is set on the driving roller 38 and the driven roller 36 so as to be transportable.

  Subsequently, the electrostatic application power source is turned on, and the electrode catalyst material 50 inside the container 46 is negatively charged and the developing roller 52 is positively charged. In addition, the fluid is supplied to the inside of the fixing roller 60 and the built-in heater 65 is turned on to start generation of the high-temperature steam 70.

  When the electrode catalyst material 50 is charged and the high temperature steam 70 is sprayed from the fixing roller 60, the photosensitive drum 40, the driving roller 38, etc. are driven to start manufacturing the electrode. By driving the driving roller 38, the electrolyte membrane 12 is sequentially conveyed to the downstream side. An electrostatic latent image is formed on the surface of the photosensitive drum 40 by the charging roller 42 and the light projecting device 44. The electrostatic latent image moves to the vicinity of the discharge port 48 of the container 46 as the photosensitive drum 40 rotates. The developing roller 52 inside the container 46 is positively charged, and the negatively charged electrode catalyst material 50 is evenly attached. When the developing roller 52 rotates and approaches the photosensitive drum 40, the electrode catalyst material 50 adhering to the developing roller 52 flies to the photosensitive drum 40 (electrostatic latent image) by Coulomb force. As a result, an image (electrode catalyst layer 20) having a predetermined pattern is formed on the surface of the photosensitive drum 40.

  The electrode catalyst layer 20 formed on the surface of the photosensitive drum 40 is transferred to the electrolyte membrane 12 by the rotation of the photosensitive drum 40. The transferred electrode catalyst layer 20 is sent downstream, and the fixing unit 34 fixes the electrode catalyst layer 20.

  The fixing roller 60 and the counter roller 62 of the fixing unit 34 hold and pressurize the electrolyte membrane 12 to which the electrode catalyst layer 20 has been transferred. At this time, high-temperature steam 70 is sprayed from the inside of the fixing roller 60. The high temperature steam 70 surrounds the periphery of the electrocatalyst material 50 on the electrolyte membrane 12 and heats it uniformly. This uniform heating tends to soften the resin component of the electrode catalyst material 50. As a result, high adhesiveness can be obtained even under relatively low pressure, and stable fixing can be achieved. Thus, a high-quality electrode can be obtained in which the electrode catalyst material 50 does not bite or fall off. When the electrolyte membrane 12 coated with the electrode catalyst layer 20 is cut with an appropriate length in the above flow, the process is completed.

  As is clear from the above description, according to the present embodiment, a higher quality fuel cell 10 electrode can be obtained. More specifically, it is possible to prevent the electrode catalyst material 50 from biting in or coming off during fixing.

  In the present embodiment, the high temperature steam 70 is sprayed from the inside of the fixing roller 60. However, if the electrode catalyst material 50 just before being pressurized can be sprayed, the high temperature steam 70 is sprayed from other places. May be. For example, as shown in FIG. 9, a sprayer 80 that sprays the high-temperature steam 70 may be provided immediately before (upstream side) the fixing roller 60, and the high-temperature steam 70 may be sprayed from the sprayer 80. The sprayer 80 is not particularly limited as long as it can spray the high-temperature steam 70 such as various known spray devices. However, it is desirable to provide a mechanism that can adjust the temperature and amount of the high-temperature steam 70 to be sprayed.

  Of course, the vapor spray from the inside of the fixing roller 60 and the vapor spray just before the fixing roller 60 may be used in combination. By using both together, the electrode catalyst material 50 can be placed in the high-temperature steam 70 for a longer time. In other words, the surface of the electrode catalyst material 50 is heated for a longer time, and softening is more likely to occur. As a result, more stable fixing can be realized.

It is the schematic which shows the structure of a fuel cell. It is a figure which shows the structure of the electrode manufacturing apparatus which is embodiment of this invention. FIG. 3 is a diagram illustrating a configuration of a fixing unit. It is an image figure which shows the mode of the electrode catalyst material adhering to an electrolyte membrane before fixing. It is an image figure which shows the mode of the electrolyte membrane and electrode catalyst material in which favorable fixation was made | formed. It is an image figure which shows the mode of the electrolyte membrane of poor fixing, and an electrode catalyst material. It is a figure which shows the temperature distribution of the electrode catalyst material in the conventional fixing method. It is a figure which shows the temperature distribution of the electrode catalyst material in this embodiment. It is a figure which shows the structure of the electrode manufacturing apparatus which is other embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Fuel cell, 12 Electrolyte membrane, 14 Anode, 16 Cathode, 18 Diffusion layer, 20 Electrode catalyst layer, 22 Separator, 30 Electrode manufacturing apparatus, 32 Transfer part, 34 Fixing part, 34 Photosensitive drum, 50 Electrode catalyst material, 60 Fixing Roller, 64 porous member, 64a through hole, 65 heater, 66 rotating shaft, 70 high temperature steam, 80 sprayer.

Claims (11)

A method for producing a fuel cell electrode, comprising attaching a powdered electrode catalyst material to the surface of a fuel cell electrolyte membrane and then fixing the electrode catalyst material to the fuel cell electrolyte membrane,
An attachment step of attaching an electrode catalyst material to the attachment surface of the fuel cell electrolyte membrane;
A fixing step of spraying high temperature steam toward the adhesion surface and fixing the electrode catalyst material to the fuel cell electrolyte membrane by pressurizing the fuel cell electrolyte membrane;
The electrode manufacturing method characterized by having. The electrode manufacturing method according to claim 1,
The high temperature steam is sprayed from the inside of a pressurizing body that pressurizes the electrolyte membrane for a fuel cell. The electrode manufacturing apparatus according to claim 1 or 2,
The high-temperature steam is sprayed immediately before being pressurized by a pressurizing body. The electrode manufacturing method according to any one of claims 1 to 3,
An electrode manufacturing method characterized in that temperature adjustment of high-temperature steam is possible. The electrode manufacturing method according to claim 2,
The electrode manufacturing method, wherein the pressing surface of the pressing body is made of a hard material in which a plurality of holes for allowing high-temperature steam to pass from the inside to the outside of the pressing body are formed uniformly. 6. The electrode manufacturing method according to claim 2 or 5, wherein the pressurizing body includes an overheating means capable of adjusting a temperature by heating a fluid supplied from the outside to generate high temperature steam. Production method. The electrode manufacturing method according to any one of claims 1 to 6,
A method for producing an electrode, wherein the pressurizing body is pressed at a temperature and pressure that do not deteriorate the electrolyte membrane for a fuel cell and the electrode catalyst material. The electrode manufacturing method according to claim 7,
An electrode manufacturing method comprising heating and pressurizing an electrolyte membrane for a fuel cell at a temperature of about 140 ° C. or less and a pressure of about 20 kgf / cm or less. The electrode manufacturing method according to any one of claims 1 to 8,
The electrode manufacturing method, wherein the high-temperature steam has a temperature that does not deteriorate the electrolyte membrane for a fuel cell and the electrode catalyst material and softens the electrode catalyst material. The electrode manufacturing method according to claim 9,
The method for producing an electrode, wherein the high-temperature steam has a temperature of about 100 ° C to 200 ° C. An electrode manufacturing apparatus for a fuel cell, in which a powdered electrode catalyst material is attached to the surface of a fuel cell electrolyte membrane, and then the electrode catalyst material is fixed to the fuel cell electrolyte membrane,
An attachment means for attaching an electrode catalyst material to an attachment surface of an electrolyte membrane for a fuel cell;
Fixing means for fixing the attached electrode catalyst material to the fuel cell electrolyte membrane;
The fixing means is
Spraying means for spraying high temperature steam toward the deposited electrocatalyst material;
A pressurizing means for pressurizing the fuel cell electrolyte membrane;
An electrode manufacturing apparatus comprising:

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