JP4701604B2 - Manufacturing method of fuel cell - Google Patents

Description

  The present invention relates to a method for manufacturing a fuel cell.

  Currently, PEFCs (solid polymer electrolyte fuel cells) are the mainstream of development for fuel cells for automobiles, portable devices, and stationary. The PEFC has a structure in which an electrolyte layer, an electrode catalyst layer, and a gas diffusion layer are laminated almost symmetrically around the electrolyte layer, and the laminated layer is sandwiched between separators.

  Of the constituents of the fuel cell, the electrode catalyst layer is conventionally formed mainly by a transfer method. Here, FIG. 4 shows a method of forming an electrode catalyst layer by a transfer method.

  As shown in FIG. 4A, a mixed solution 31 obtained by mixing a catalyst, an electrolyte solution, and a solvent is cast on a highly peelable film such as a PTFE (polytetrafluoroethylene) film 32. Here, the electrolyte solution is a liquid electrolyte. Thereby, the electrode catalyst layer 33 having an arbitrary pattern shape is formed.

  Then, after the electrode catalyst layer 33 is dried on the PTFE film 32, as shown in FIG. 4B, the electrolyte layer 34 is placed on the PTFE film 32, and the PTFE film 32 and the electrolyte layer 34 are hot-pressed. .

Thereafter, as shown in FIG. 4C, the PTFE film 32 and the electrolyte layer 34 are turned upside down, and the PTFE film 32 is peeled off. Thereby, the electrode catalyst layer 2 is transcribe | transferred to the electrolyte layer 34 (for example, refer patent document 1).
JP 2003-123792 A

  The electrode catalyst layer is in contact with the electrolyte layer in a symmetrical shape, and serves as a catalyst in a reaction field called a three-phase interface for generating water from hydrogen and oxygen, and electricity generated in the reaction field ( It plays the role of a path that collects (electron). For this reason, in the formation of the electrode catalyst layer, it is required to form the electrode catalyst layer so that the electrode catalyst layer has a desired shape and the film thickness is uniform in the plane.

  However, in the above-described method, it is necessary to cast the electrode catalyst layer 33 so that the film thickness of the electrode catalyst layer 33 is uniform over the entire surface. In hot pressing, the film thickness of the electrode catalyst layer 33 is over the entire surface. It is necessary to control the pressure so that it is uniform. Thus, in the above-described method, it is necessary to control the film thickness of the electrode catalyst layer 33 to be uniform in each of the casting process and the hot pressing process. There were two processes that caused variations.

  Further, at the time of transfer, a part of the electrode catalyst layer 33 may be lost due to transfer failure. In particular, when the shape of the electrode catalyst layer 33 is a fine shape, transfer defects frequently occur, and the shape accuracy of the formed electrode catalyst layer 33 is low.

  Such a problem is a problem that occurs not only when the electrode catalyst layer is formed, but also when the electrode layer and the catalyst layer are formed separately.

  In view of the above points, an object of the present invention is to provide a method of manufacturing a fuel cell that can form an electrode catalyst layer or an electrode layer with higher accuracy than conventional manufacturing methods.

In order to achieve the above object, according to the first aspect of the present invention, the step of preparing the electrolyte layer, the step of preparing the gas diffusion layer, and the gas diffusion layer are prepared, and then the gas diffusion layer is formed by screen printing. As a material to be coated, the step of forming an electrode catalyst layer on the surface of the gas diffusion layer by directly applying a solution containing a catalyst and a solvent to the surface of the material to be coated, and the electrolyte layer and the electrode catalyst layer are bonded together. it is, an electrode catalyst layer disposed on both sides of the electrolyte layer, the outer side of the electrode catalyst layers have a placing a gas diffusion layer,
In the step of forming the electrode catalyst layer, the sealed container (21) that seals the material to be coated and the surface plate part (11) that fixes the material to be coated, and the inside of the sealed container with a negative pressure with respect to the atmosphere outside the sealed container Using a screen printer having a means (12) for setting the atmosphere and a means (23) for introducing an inert gas into the sealed container, the inert gas is introduced into the sealed container with the sealed container as a negative pressure atmosphere. However , an electrode catalyst layer is formed .

  In general, film thickness control of printed matter by the screen printing method is easier than the film thickness control at the time of casting by the above transfer method and the film thickness control at the time of hot pressing. Compared with the above-mentioned cast and hot press, the film thickness of the printed matter is high.

  Further, according to the screen printing method, an electrode catalyst layer having a desired thickness can be formed in one step by arbitrarily adjusting the thickness of the screen to be used. This reduces the number of processes that cause in-plane variations in the thickness of the formed electrocatalyst layer compared to the conventional fuel cell manufacturing method in which the electrocatalyst layer is formed by the transfer method. Therefore, the accuracy of the film thickness of the electrode catalyst layer can be made higher than that of the conventional manufacturing method.

  In addition, although it is difficult to form an electrode catalyst layer having a fine pattern shape by the transfer method, the screen printing method has a fine pattern shape as compared to the case where the electrode catalyst layer is formed by the transfer method. An electrode catalyst layer can be formed.

  From the above, according to the present invention, the electrode catalyst layer can be formed with higher accuracy than the conventional fuel cell manufacturing method in which the electrocatalyst layer is formed by the transfer method.

  In addition, it is preferable to use what contains electrolyte as a solution apply | coated to a to-be-coated material.

  Further, the material to which the solution is applied is a gas diffusion layer as shown in claim 1, an electrolyte layer as shown in claim 3, or an electrolyte layer and a gas diffusion layer as shown in claim 5. Or both.

  As shown in claim 5, in the case where both the electrolyte layer and the gas diffusion layer are applied materials, an electrode catalyst layer having a low electrical resistance is directly formed on the surfaces of both the electrolyte layer and the gas diffusion layer, Thereafter, the electrode catalyst layers are bonded together. For this reason, the contact resistance (electric resistance) between the electrolyte layer and the gas diffusion layer can be reduced as compared with the case where the electrode catalyst layer is formed only on the surface of the electrolyte layer.

  Further, as shown in claims 2, 4, and 6, the material to be coated (a gas diffusion layer in claim 2, an electrolyte layer in claim 4, and both an electrolyte layer and a gas diffusion layer in claim 6) is previously aligned. By forming the mark, a fine electrode catalyst layer can be easily formed.

In the invention according to claim 9 , after preparing the electrolyte layer, and after preparing the electrolyte layer, a solution containing a metal and a solvent is directly applied to the surface of the electrolyte layer by a screen printing method. forming an electrode layer on the surface, disposing a catalyst layer on the outer electrode layer, and a step of disposing the gas diffusion layer on the outer side of the electrode catalyst layers possess,
In the step of forming the electrode layer, the sealed container (21) that seals the material to be coated and the surface plate (11) that fixes the material to be coated, and the inside of the sealed container in a negative pressure atmosphere with respect to the atmosphere outside the sealed container Using a screen printer having means (12) and means (23) for introducing an inert gas into the sealed container, and introducing the inert gas into the sealed container with the sealed container as a negative pressure atmosphere. However , an electrode layer is formed .

In this way, not only the electrode catalyst layer but also the electrode layer can be formed. In addition, as shown in claim 10 , it is preferable to previously form an alignment mark on the electrolyte layer.

Further, as shown in claim 13, when the material to be coated is an electrolyte layer, it is preferable to use an electrolyte layer reinforced with a porous material. This is to prevent the electrolyte layer from swelling and shrinking with the solvent when the solution is applied to the electrolyte layer.

Further, in the formation of the electrode catalyst layer or the electrode layer, as shown in claims 7 and 11 , a portion of the surface plate portion (11) for fixing the material to be coated and a portion to which the material to be coated is fixed and the material to be coated are fixed. A solvent which is provided with pores (11a) in a portion that is not to be used, sucks the material to be coated from the pores using a screen printing machine having suction means (12) for sucking from the pores, and is vaporized from the solution. It is preferable to form the electrode catalyst layer or the electrode layer while sucking the water.

In addition, as shown in claims 8 and 12 , a screen printer provided with a means for adjusting the temperature of the surface plate portion (11) for fixing the material to be coated is used, and the temperature of the surface plate portion is a temperature equal to or higher than the boiling point of the solvent. It is preferable to form an electrode catalyst layer or an electrode layer while holding the substrate.

  In addition, the code | symbol in the bracket | parenthesis of each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

A second embodiment described below is an embodiment of the present invention described in the claims, and the first embodiment is an embodiment serving as a reference example of the present invention. In addition, of the third embodiment and other embodiments, a portion related to the first embodiment is an embodiment serving as a reference example, and a portion related to the second embodiment is an embodiment of the present invention.
(First embodiment)
FIG. 1 shows the configuration of a fuel cell according to the first embodiment of the present invention. This fuel cell is, for example, a PEFC, and as shown in FIG. 1, an electrolyte layer 1, an electrode catalyst layer 2 disposed on both sides of the electrolyte layer 1, and a gas diffusion layer disposed outside the electrode catalyst layer 2 3 is provided. And these have the structure pinched | interposed by the separator 4 with the gas flow path 4a.

  Next, a method for manufacturing this fuel cell will be described. The manufacturing method of the present embodiment is different from the conventional manufacturing method in that a screen printing method is used as a method for forming the electrode catalyst layer 2, and the others are the same as the conventional method. Therefore, below, the formation method of the electrode catalyst layer 2 is mainly demonstrated.

  First, a step of preparing the electrolyte layer 1 is performed. In this step, an electrolyte layer 1 reinforced with a porous material is prepared. The electrolyte layer 1 is formed by putting an electrolyte in a porous material, and the porous material is a framework.

  Then, the process of forming the electrode catalyst layer 2 on the surface of the electrolyte layer 1 is performed by screen printing. Here, FIG. 2 shows a configuration of a screen printing machine used when the electrode catalyst layer 2 is formed. As shown in FIG. 2, the screen printing machine used in this embodiment includes a surface plate unit 11, a pump 12, an exclusion device 13, a frame 14, a screen 15, and a squeegee 16.

  The surface plate portion 11 fixes a material to be coated (in FIG. 2, the electrolyte layer 1) to which ink is applied. As shown in FIG. 2, the surface plate portion 11 is provided with pores 11 a on the surface to which the material to be coated is fixed. The pores 11a are provided not only in a range where the material to be coated is fixed but also in a portion where the material to be coated is not fixed in the surface plate part 11, and are provided in the surface plate part 11 over a wide range. It has been.

  Further, the screen printing machine has means capable of adjusting the temperature of the surface plate portion 11 so that the temperature of the surface plate portion 11 can be maintained at a predetermined temperature. Thereby, the screen printer of this embodiment can hold | maintain the site | part to which a to-be-coated material is fixed to predetermined | prescribed temperature at least.

  The pump 12 is connected to the pores 11 a of the surface plate part 11, and sucks the material to be coated and the gas located on the surface of the surface plate part 11 from the pores 11 a. As will be described later, an oil-free (dry) pump is used as the pump 12 in order to suck a solvent such as an alcohol solvent. This pump 12 corresponds to the suction means of the present invention.

  The exclusion device 13 is connected to the pump 12, and excludes the solvent sucked by the pump 12 from the pores 11 a from the pump 12.

  The frame 14 is attached around the screen 15. The screen 15 has a portion 15a etched into an arbitrary pattern shape. The ink is applied to the material to be coated by pushing the ink from the etched portion 15a to the material to be coated by the squeegee 16.

  In the step of forming the electrode catalyst layer 2, the screen printer configured as described above is used. First, as shown in FIG. 2, the prepared electrolyte layer 1 is placed on the surface plate portion 11. Subsequently, screen printing is performed on the electrolyte layer 1. This printing method is the same as a general screen printing method. Specifically, by applying pressure to the squeegee 16 on the screen 15, the ink is pushed out from the etched portion 15 a of the screen 15. As a result, ink is directly applied on the surface of the electrolyte layer 1, and the electrode catalyst layer 2 having a desired shape is formed on the surface of the electrolyte layer 1.

  Here, as the ink, a mixed solution in which a catalyst, an electrolyte solution, and a solvent are mixed is used. This mixed solution corresponds to the solution of the present invention. As the catalyst and the solvent, for example, platinum-supported carbon and alcohol solvent can be used, respectively, as in the conventional case. The electrolyte solution is a solution in which the electrolyte is liquefied with a solvent such as an alcohol solvent, and serves as a binder for the catalyst. Further, the reason why the electrolyte is included in the mixed solution is to expand the electrolyte region three-dimensionally from the electrolyte layer 1 into the electrode catalyst layer 2 to expand the three-phase interface region.

  Thus, when a mixed solution containing an electrolyte solution is used, the mixed solution contains a component (solvent) that dissolves the electrolyte. For this reason, when this mixed solution is applied directly on the surface of the electrolyte layer 1, there is a possibility that the electrolyte layer 1 may swell and shrink with a solvent depending on the electrolyte layer 1. If the electrolyte layer 1 swells, unevenness may occur on the surface of the electrolyte layer 1, and therefore, the thickness of the electrode catalyst layer 2 may be uneven in the subsequent coating process, or the electrolyte layer 1 may dip on the uneven surface. May occur.

  Therefore, in the present embodiment, in order to prevent this, using the screen printer having the above-described configuration, the screen printer is controlled as follows to directly apply ink onto the surface of the electrolyte layer 1. I am doing so.

  First, the pump 12 is operated so as to suck the electrolyte layer 1 from the pores 11a of the surface plate part 11. As a result, when the mixed solution is applied to the surface of the electrolyte layer 1, the electrolyte layer 1 can be adsorbed to the surface plate part 11 and the vaporized solvent can be removed by suction from the electrode catalyst layer 2 on the surface of the electrolyte layer 1. it can. In other words, since the air is sucked from the pores 11a by the pump 12, vaporization of the solvent in the mixed solution applied on the surface of the electrolyte layer 1 can be promoted. Moreover, since the pore 11a is provided in the wide range of the surface plate part 11, vaporization of the solvent in the mixed solution apply | coated on the surface of the electrolyte layer 1 is accelerated | stimulated.

  Secondly, the platen unit 11 controls the temperature adjusting means so that the temperature of the solvent in the above mixed solution is easily vaporized, for example, a temperature near the boiling point of the solvent. Thereby, vaporization of the solvent in the mixed solution when the mixed solution is applied to the surface of the electrolyte layer 1 is promoted.

  Third, when the mixed solution is applied to the surface of the electrolyte layer 1, the extrusion time and the distance between the electrolyte membrane 1 and the screen 15 are adjusted so that the solvent in the mixed solution is easily vaporized.

  In this way, in the present embodiment, the mixed solution is dried at the moment when the mixed solution is applied to the electrolyte layer 1. Thereby, the influence of the swelling of the electrolyte layer 1 due to the solvent can be suppressed, and the mixed solution can be applied onto the surface of the electrolyte layer 1.

  In the present embodiment, the electrolyte layer 1 reinforced with a porous material is used to suppress swelling and shrinkage of the electrolyte layer 1 due to the solvent in the mixed solution. In place of the porous material, the electrolyte layer 1 reinforced with short fibers or long fibers made of an organic material or an inorganic material can also be used.

  In addition, when apply | coating (printing) a mixed solution to the electrolyte layer 1 by a screen printing method, since it can print by adjusting the pressure to the printing surface of the electrolyte layer 1 arbitrarily, the solvent in a mixed solution The amount added may be small. For this reason, the amount of the solvent added to the mixed solution used in the screen printing method is smaller than that of the mixed solution used in the conventional transfer method.

  In the case where the fine electrode catalyst layer 2 is formed on the surface of the electrolyte layer 1, in the step of preparing the electrolyte layer 1, the electrolyte layer 1 having an alignment mark previously formed on the surface is prepared. In the step of forming the electrode catalyst layer 2, it is desirable to confirm the formation position of the electrode catalyst layer 2 with reference to the alignment mark and form the electrode catalyst layer 2. Thereby, alignment with the electrolyte layer 1 and the electrode catalyst layer 2 is easy, and the fine electrode catalyst layer 2 can be formed easily.

  After the step of forming the electrode catalyst layer 2, a step of preparing the gas diffusion layer 3 is performed. And the process of arrange | positioning the gas diffusion layer 3 on the outer side of the electrode catalyst layer 2 is performed. In this step, the gas diffusion layer 3 is bonded to the electrode catalyst layer 2.

  Then, the process of preparing the separator 4 and the process of arrange | positioning the separator 4 outside the gas diffusion layer 3 are performed. Thereby, the fuel cell shown in FIG. 1 is completed.

  In the present embodiment, as described above, the electrode catalyst layer 2 is formed on the surface of the electrolyte layer 1 by directly applying the mixed solution onto the surface of the electrolyte layer 1 by screen printing.

  In the screen printing method, the thickness of the electrode catalyst layer 2 formed on the surface of the electrolyte layer 1 is determined by the thickness of the screen 15 and the amount of ink. For this reason, it is easier to control the film thickness of the electrode catalyst layer 2 in the screen printing method than in the film thickness control in the casting process or the hot press process in the transfer method described in the background art section. The accuracy of the film thickness of the formed electrode catalyst layer 2 is high.

Further, in the screen printing method, if the thickness of the screen 15 is arbitrarily changed so as to ensure the catalyst component amount (g / cm ² ) necessary for the electrode catalyst layer 2, the so-called basis weight, one application of the mixed solution is performed. Thus, the electrode catalyst layer 2 having a desired thickness can be formed on the surface of the electrolyte layer 1.

  Thereby, according to the screen printing method, compared with the transfer method described above, it is possible to reduce processes that cause in-plane variations in the film thickness of the formed electrocatalyst layer 2, and thus the electrode catalyst layer The film thickness accuracy of 2 can be made higher than that of the conventional manufacturing method.

  Moreover, the electrode catalyst layer having a fine pattern shape could not be formed by the transfer method. However, according to the screen printing method, the electrode having the fine pattern shape was compared with the case where the electrode catalyst layer was formed by the transfer method. A catalyst layer can be formed.

  Therefore, according to the fuel cell manufacturing method of the present embodiment, the electrode catalyst layer 2 can be formed with higher accuracy than the conventional fuel cell manufacturing method in which the electrocatalyst layer 2 is formed by the transfer method. Can do. Thereby, the electrode catalyst layer 2 having a fine shape can be formed with a higher yield than conventional.

  Further, according to the fuel cell manufacturing method of the present embodiment, since the electrode catalyst layer 2 can be formed by applying the mixed solution once, the number of steps and the process time when forming the electrode catalyst layer 2 are reduced. Compared with the conventional manufacturing method of a fuel cell, it can be reduced. Thereby, compared with the conventional manufacturing method of a fuel cell, the manufacturing cost of a fuel cell can be reduced.

  In this embodiment, the case where the material to be coated to which the mixed solution is applied is the electrolyte layer 1 has been described as an example. However, the present invention is not limited thereto, and the material to be coated can be the gas diffusion layer 3.

  In this case, after the step of preparing the electrolyte layer 1 and the step of preparing the gas diffusion layer 3, the surface of the gas diffusion layer 3 is directly applied to the surface of the gas diffusion layer 3 by screen printing. The step of forming the electrode catalyst layer 2 is performed. The formation method of the electrode catalyst layer 2 at this time is the same as the case where the above-mentioned material to be coated is the electrolyte layer 1.

  Then, the process which arrange | positions the electrode catalyst layer 2 on the both sides of the electrolyte layer 1, and arrange | positions the gas diffusion layer 3 on the outer side of the electrode catalyst layer 2 by bonding the electrolyte layer 1 and the electrode catalyst layer 2 is performed. And the process of arrange | positioning the separator 4 outside the gas diffusion layer 3 is performed. In this way, a fuel cell can also be manufactured.

  Also in this case, since the electrode catalyst layer 2 is formed on the surface of the gas diffusion layer 3 by the screen printing method, it has the same effect as the case where the above-mentioned material to be coated is the electrolyte layer 1. . In this case, since the mixed solution is applied onto the surface of the gas diffusion layer 3, the electrolyte layer 1 is not swollen by the solvent.

  Further, the material to be coated can be both the electrolyte layer 1 and the gas diffusion layer 3. In this case, after the step of preparing the electrolyte layer 1 and the step of preparing the gas diffusion layer 3, the mixed solution is directly applied to the surfaces of the electrolyte layer 1 and the gas diffusion layer 3 by a screen printing method. 1 and the process of forming the electrode catalyst layer 2 on the surface of the gas diffusion layer 3 are performed. The formation method of the electrode catalyst layer 2 at this time is also the same as that in the case where the above-described material to be coated is the electrolyte layer 1.

  Thereafter, the electrode catalyst layer 2 formed on the surface of the electrolyte layer 1 and the electrode catalyst layer 2 formed on the surface of the gas diffusion layer 3 are bonded together to dispose the electrode catalyst layer 2 on both sides of the electrolyte layer 1, A step of arranging the gas diffusion layer 3 outside the electrode catalyst layer 2 is performed. And the process of arrange | positioning the separator 4 outside the gas diffusion layer 3 is performed. In this way, a fuel cell can also be manufactured.

  Here, the electrode catalyst layer 2 has a lower electrical resistance than the electrolyte layer 1 and the gas diffusion layer 3. Therefore, in this way, the electrode catalyst layer 2 is formed on the surfaces of both the electrolyte layer 1 and the gas diffusion layer 3, and these are bonded together, so that the electrolyte layer 1, the electrode catalyst layer 2, the gas diffusion layer 3 and The contact resistance between the electrolyte layer 1 and the electrode catalyst layer 2 and the contact resistance between the electrode catalyst layer 2 and the gas diffusion layer 3 can be reduced as compared with the case where the layers are stacked.

  Here, conventionally, a method in which the electrode catalyst layer 2 is formed on both the surface of the electrolyte layer 1 and the surface of the gas diffusion layer 3 by a transfer method and these electrode catalyst layers 2 are attached to each other is conceivable. However, the screen printing method can form the electrode catalyst layer 2 with higher accuracy than the transfer method. From this, even when the material to be coated is both the electrolyte layer 1 and the gas diffusion layer 3, the electrode catalyst layer 2 can be formed with higher accuracy than the transfer method.

  Even when the material to be coated is the gas diffusion layer 3 or both the electrolyte layer 1 and the gas diffusion layer 3, an alignment mark is provided so that the fine electrode catalyst layer 2 can be easily formed on the material to be coated. It is good to form in advance.

(Second Embodiment)
This embodiment differs from the first embodiment in the screen printing method.

  FIG. 3 shows the configuration of the screen printer in the second embodiment. In the present embodiment, as shown in FIG. 3, a screen printing machine having a sealed container 21, an inert gas introduction port 22, and an inert gas introduction means 23 in addition to the screen printing machine shown in FIG. 2. Is used. Hereinafter, the case where the material to be coated is the electrolyte layer 1 will be described as an example, but the same applies to the case where the material to be coated is the gas diffusion layer 3 or both the electrolyte layer 1 and the gas diffusion layer 3. .

  The sealed container 21 of the screen printing machine seals the surface plate portion 11 and the electrolyte layer 1 fixed on the surface plate portion 11. However, since the inert container 22 is provided in the sealed container 21, the sealed container 21 has a pseudo-sealed structure.

  The inert gas introduction means 23 is connected to the inert gas introduction port 22. Nitrogen gas can be used as the inert gas.

  In this embodiment, in the step of forming the electrode catalyst layer 2 described in the first embodiment, an inert gas is introduced into the sealed container 21 from the inert gas inlet 22 by the inert gas introduction means 23. Then, screen printing is performed while the internal atmosphere of the sealed container 21 is convected.

  Thus, in this embodiment, the electrolyte layer 1 and the surface plate part 11 are sealed by the sealed container 21. For this reason, when the mixed solution is applied to the electrolyte layer 1, even if the solvent in the mixed solution is vaporized, it can be kept in the sealed container 21.

  Further, since the gas inside the sealed container 21 is sucked from the pump 12, the inside of the sealed container 21 becomes a negative pressure atmosphere with respect to the atmosphere outside the sealed container 21. Thereby, when a mixed solution is apply | coated to the electrolyte layer 1, the vaporization of the solvent in a mixed solution can be accelerated | stimulated. In this embodiment, the pump 12 corresponds to a means for creating a negative pressure atmosphere of the present invention.

  Moreover, in this embodiment, since the atmosphere in the airtight container 21 is convected by introducing an inert gas into the airtight container 21, when the mixed solution is applied to the electrolyte layer 1, Vaporization of the solvent can be promoted.

  When the inert gas inlet 22 is not provided in the sealed container 21, the pump 12 draws too much gas inside the sealed container 21 so that the electrolyte layer 1 is drawn into the pores 11a and the electrolyte layer 1 is deformed. There is a risk of doing. As a means for preventing this, a method of introducing air into the sealed container 21 can be considered. However, in the air atmosphere, the electrode catalyst layer 2 may be oxidized, or the catalyst in the electrode catalyst layer 2 may spontaneously ignite.

  Therefore, as in the present embodiment, an inert gas introduction port 22 is provided in the sealed container 21 and an inert gas is introduced into the sealed container 21 to keep the inside of the sealed container 21 at a constant negative pressure. The deformation of the electrolyte layer 1 can be suppressed.

  As described above, in FIG. 3, the case where the pump 12 is used as an example of the means for setting the inside of the sealed container 21 to the negative pressure atmosphere has been described as an example. However, instead of the pump 12, another negative pressure atmosphere is used. Means can also be used.

(Third embodiment)
In the first and second embodiments, the case where the fuel cell including the electrode catalyst layer 2 is manufactured has been described as an example. However, the present embodiment is also applicable to the case where the electrode layer and the catalyst layer are separately formed instead of the electrode catalyst layer 2. The invention can be applied.

  A case will be described in which a fuel cell is manufactured that includes an electrolyte layer, electrode layers disposed on both sides of the electrolyte layer, and a catalyst layer and a gas diffusion layer disposed in order on the outside of the electrode layer. In this case, after preparing the electrolyte layer and preparing the electrolyte layer, the electrode layer is applied to the surface of the electrolyte layer by directly applying a solution containing a metal and a solvent to the surface of the electrolyte layer by screen printing. A process of forming is performed.

  In this step, a metal paste in which the metal is liquefied with a solvent is used instead of the mixed solution used in the first embodiment. As the metal, it is preferable to use a metal having acid resistance and high conductivity. For example, silver, gold, platinum or the like can be used. The screen printer and printing method used are the same as those in the first embodiment.

  Also in the present embodiment, it is preferable to previously form alignment marks in the electrolyte layer so that a fine electrode layer can be easily formed on the surface of the electrolyte layer in this step.

  Then, the process of arrange | positioning a catalyst layer on the outer side of an electrode layer is performed, and the process of arrange | positioning a gas diffusion layer on the outer side of an electrode catalyst layer is performed.

  Also in this embodiment, since the electrode layer is formed by the screen printing method, it has the same effect as the first embodiment.

(Other embodiments)
In each of the above-described embodiments, when the electrode catalyst layer 2 or the electrode layer is formed on the surface of the electrolyte layer 1, the following steps are performed before the step of forming the electrode catalyst layer 2 and the like on the surface of the electrolyte layer 1. Can also be done.

  For example, when using the electrolyte membrane 1 that is highly hygroscopic and easily deforms even by absorbing moisture in the air, the electrolyte layer 1 is formed before performing the step of forming the electrode catalyst layer 2 and the like on the surface of the electrolyte layer 1. There are times when the surface of the surface is uneven.

  Therefore, when such an electrolyte layer 1 is used, immediately before applying the mixed solution to the electrolyte layer 1, the electrolyte membrane 1 is fixed to the surface plate part 11, and a scrubber or a doctor blade attached to the screen printer is used. Then, a process of tracing the surface of the electrolyte layer 1 is performed in a state where an appropriate pulling pressure is applied. Thereby, the unevenness generated on the electrolyte membrane 1 is corrected to be flat.

  Thereafter, in the step of forming the electrode catalyst layer 2 and the like, the electrode catalyst layer 2 is formed on the surface of the electrolyte layer 1 by screen printing as in the above-described embodiments.

  As described above, the surface of the electrolyte layer 1 is smoothed immediately before the mixed solution is applied, and then the mixed solution is applied to make the film thickness of the electrode catalyst layer 2 or the like uneven. It is possible to suppress the occurrence of dripping on the uneven surface.

  In each of the above embodiments, the case where PEFC is manufactured has been described as an example. However, in the fuel cell in which an electrolyte layer, an electrode catalyst layer (or an electrode and a catalyst layer), and a gas diffusion layer are sequentially stacked. If so, the present invention can be applied to other fuel cell manufacturing methods. For example, the present invention can be applied to a method for manufacturing AFC (alkaline fuel cell), PAFC (phosphoric acid fuel cell), MCFC (molten carbonate fuel cell), and SOFC (solid electrolyte fuel cell). it can.

It is a figure which shows the structure of the fuel cell of this invention. It is sectional drawing of the screen printer in 1st Embodiment of this invention. It is sectional drawing of the screen printer in 2nd Embodiment of this invention. It is a figure for demonstrating the formation method of the conventional electrode catalyst layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electrolyte layer, 2 ... Electrode catalyst layer, 3 ... Gas diffusion layer, 4 ... Separator,
11 ... Surface plate, 12 ... Pump, 13 ... Exclusion device, 14 ... Frame,
15 ... screen, 16 ... squeegee, 21 ... sealed container,
22 ... Inert gas introduction port, 23 ... Inert gas introduction means.

Claims (13)

In a method for producing a fuel cell comprising an electrolyte layer (1), an electrode catalyst layer (2) disposed on both sides of the electrolyte layer, and a gas diffusion layer (3) disposed outside the electrode catalyst layer,
Preparing the electrolyte layer;
Preparing the gas diffusion layer;
After preparing the gas diffusion layer, by applying a solution containing a catalyst and a solvent directly on the surface of the material to be coated, using the gas diffusion layer as a material to be coated by screen printing, Forming the electrode catalyst layer on the surface;
Wherein by laminating an electrolyte layer and a said electrode catalyst layer, wherein the placing the electrode catalyst layer on both sides of the electrolyte layer, have a placing said gas diffusion layer on the outer side of the electrode catalyst layer,
In the step of forming the electrode catalyst layer, a sealed container (21) that seals the material to be coated and a surface plate part (11) that fixes the material to be coated, and the sealing against the atmosphere outside the sealed container Using a screen printing machine having means (12) for making the inside of the container a negative pressure atmosphere and means (23) for introducing an inert gas into the inside of the sealed container, the inside of the sealed container is made a negative pressure atmosphere, and the sealing A method for producing a fuel cell , comprising forming the electrode catalyst layer while introducing an inert gas into the container . In the step of preparing the gas diffusion layer, the gas diffusion layer having an alignment mark formed in advance on the surface is prepared,
The step of forming the electrode catalyst layer on the surface of the gas diffusion layer forms the electrode catalyst layer on the surface of the gas diffusion layer with reference to the alignment mark. Manufacturing method of fuel cell. In a method for producing a fuel cell comprising an electrolyte layer (1), an electrode catalyst layer (2) disposed on both sides of the electrolyte layer, and a gas diffusion layer (3) disposed outside the electrode catalyst layer,
Preparing the electrolyte layer;
After preparing the electrolyte layer, by applying a solution containing a catalyst and a solvent directly on the surface of the material to be coated, using the electrolyte layer as a material to be coated by screen printing, the surface of the electrolyte layer is applied. Forming the electrode catalyst layer;
Preparing the gas diffusion layer;
By laminating the said gas diffusion layer and said electrocatalyst layer, have a placing said gas diffusion layer on the outer side of the electrode catalyst layer,
In the step of forming the electrode catalyst layer, a sealed container (21) that seals the material to be coated and a surface plate part (11) that fixes the material to be coated, and the sealing against the atmosphere outside the sealed container Using a screen printing machine having means (12) for making the inside of the container a negative pressure atmosphere and means (23) for introducing an inert gas into the inside of the sealed container, the inside of the sealed container is made a negative pressure atmosphere, and the sealing A method for producing a fuel cell , comprising forming the electrode catalyst layer while introducing an inert gas into the container . In the step of preparing the electrolyte layer, the electrolyte layer having an alignment mark formed in advance on the surface is prepared,
4. The fuel cell according to claim 3, wherein in the step of forming the electrode catalyst layer on the surface of the electrolyte layer, the electrode catalyst layer is formed on the surface of the electrolyte layer with reference to the alignment mark. Manufacturing method. In a method for producing a fuel cell comprising an electrolyte layer (1), an electrode catalyst layer (2) disposed on both sides of the electrolyte layer, and a gas diffusion layer (3) disposed outside the electrode catalyst layer,
Preparing the electrolyte layer;
Preparing the gas diffusion layer;
After preparing the electrolyte layer and the gas diffusion layer, a solution containing a catalyst and a solvent is directly applied to the surface of the material to be coated by the screen printing method using the electrolyte layer and the gas diffusion layer as a material to be coated. And forming the electrode catalyst layer on both surfaces of the electrolyte layer and the gas diffusion layer;
The electrode catalyst layer is disposed on both sides of the electrolyte layer by bonding the electrode catalyst layer formed on the electrolyte layer surface and the electrode catalyst layer formed on the gas diffusion layer surface, and the electrode have a placing said gas diffusion layer on the outer side of the catalyst layer,
In the step of forming the electrode catalyst layer, a sealed container (21) that seals the material to be coated and a surface plate part (11) that fixes the material to be coated, and the sealing against the atmosphere outside the sealed container Using a screen printing machine having means (12) for making the inside of the container a negative pressure atmosphere and means (23) for introducing an inert gas into the inside of the sealed container, the inside of the sealed container is made a negative pressure atmosphere, and the sealing A method for producing a fuel cell , comprising forming the electrode catalyst layer while introducing an inert gas into the container . In the step of preparing the electrolyte layer, the electrolyte layer having an alignment mark formed in advance on the surface is prepared,
In the step of preparing the gas diffusion layer, the gas diffusion layer having an alignment mark formed in advance on the surface is prepared,
In the step of forming the electrode catalyst layer on the surfaces of the electrolyte layer and the gas diffusion layer, the electrode catalyst layer is formed on the surfaces of the electrolyte layer and the gas diffusion layer with reference to the alignment mark. A method for producing a fuel cell according to claim 5. Wherein in the step of forming the electrode catalyst layer, and pores (11a) is provided above the site where the site and the object to be coated material to be coated material is secured is not fixed among the platen portion (11), wherein Using the screen printing machine having the suction means (12) for sucking from the pores, the electrode catalyst layer is drawn while sucking the material to be coated from the pores and sucking the solvent evaporated from the solution. the method of manufacturing a fuel cell according to any one of claims 1 to 6, characterized in that to form the. In the step of forming the electrode catalyst layer, using the screen printing machine provided with means for adjusting the temperature of the surface plate (11), while maintaining the temperature of the surface plate portion to a temperature higher than the boiling point of the solvent the method of manufacturing a fuel cell according to any one of claims 1 to 7, characterized in that to form the electrode catalyst layer. In a method of manufacturing a fuel cell, comprising: an electrolyte layer; an electrode layer disposed on both sides of the electrolyte layer; and a catalyst layer and a gas diffusion layer disposed in order on the outside of the electrode layer.
Preparing the electrolyte layer;
After preparing the electrolyte layer, the step of forming the electrode layer on the surface of the electrolyte layer by directly applying a solution containing a metal and a solvent on the surface of the electrolyte layer by screen printing;
Disposing the catalyst layer outside the electrode layer;
Have a placing said gas diffusion layer on the outside of the catalyst layer,
In the step of forming the electrode layer, a sealed container (21) that seals the material to be coated and a surface plate part (11) that fixes the material to be coated, and the sealed container against an atmosphere outside the sealed container Using a screen printing machine having a means (12) for setting the inside to a negative pressure atmosphere and a means (23) for introducing an inert gas into the inside of the sealed container, the inside of the sealed container is set to a negative pressure atmosphere, and the sealed container A method for producing a fuel cell , comprising forming the electrode layer while introducing an inert gas therein . In the step of preparing the electrolyte layer, the electrolyte layer having an alignment mark formed in advance on the surface is prepared,
10. The fuel cell manufacturing method according to claim 9 , wherein in the step of forming the electrode layer on the surface of the electrolyte layer, the electrode layer is formed on the surface of the electrolyte layer with reference to the alignment mark. Method. In the step of forming a pre-Symbol electrode layer, and pores (11a) is provided at a site site and the object to be coated material wherein the coating material is secured within the plate portion (11) is not fixed, the the screen printer used with a suction device which performs suction from the pores (12), both to suck the object to be coated material from the pores, while attracting the solvent vaporized from the solution, prior Symbol electrode layer The method of manufacturing a fuel cell according to claim 9 or 10 , wherein: is formed. In the step of forming a pre-Symbol electrode layer, using the screen printing machine provided with means for adjusting the temperature of the surface plate (11), while maintaining the temperature of the surface plate portion to a temperature higher than the boiling point of the solvent the method of manufacturing a fuel cell according to any one of claims 9 to 11, characterized in that to form a pre-Symbol electrode layer. The step of preparing the electrolyte layer includes preparing the electrolyte layer reinforced with a porous material, according to any one of claims 3, 4 , 5 , 6 , 9 , 10, 11, 12. The manufacturing method of the fuel cell of description.

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