JP5907057B2 - ELECTROLYTE MEMBRANE FOR FUEL CELL AND MEMBRANE ELECTRODE ASSEMBLY AND METHOD FOR PRODUCING ELECTROLYTE MEMBRANE FOR FUEL CELL - Google Patents

Description

  The present invention relates to an electrolyte membrane for a fuel cell, a membrane electrode assembly, and a method for producing an electrolyte membrane for a fuel cell.

  The fuel cell rarely continues a uniform power generation operation, and the generated power frequently moves up and down and is repeatedly turned on and off. For this reason, the electrolyte membrane repeatedly expands / contracts due to the vertical movement of the power generated by the fuel cell and the on / off of power generation, and this repeated expansion / contraction can cause distortion of the electrolyte membrane. Since such distortion causes damage to the electrolyte membrane, a technique for reinforcing the electrolyte membrane by providing two or more porous reinforcing layers in the electrolyte membrane has been proposed (for example, Patent Document 1).

JP 2005-276747 A

  By the way, the stress associated with the distortion of the electrolyte membrane is not uniform in the state of occurrence and the degree of residual on the membrane surface of the electrolyte membrane, and is different between the power generation region at the center of the membrane and the peripheral region surrounding it. Become prominent. This is because in the power generation region, since the rigidity of the members such as the gas diffusion layer and the separator existing in the region is higher than that of the electrolyte membrane, the stress is distributed. Further, in the peripheral region, for the purpose of supplying gas to the power generation region, only the electrolyte membrane exists so-called alone, so that there is a risk of film damage in the peripheral region with repeated expansion / contraction. Since the above method lacks consideration for the power generation region and the peripheral region, it has been requested to increase the effectiveness of avoiding or suppressing damage to the electrolyte membrane. In addition, in the electrolyte membrane for fuel cells, cost reduction, resource saving, ease of production, improvement in usability, etc. have been desired.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

  (1) According to one aspect of the present invention, an electrolyte membrane for a fuel cell is provided. The electrolyte membrane for a fuel cell includes at least one porous reinforcing layer in a state in which an electrolyte is contained in pores, and the porous reinforcing layer includes a power generation region of the electrolyte membrane and a peripheral edge surrounding the power generation region. The region has a different density, and the peripheral region is denser than the power generation region. The electrolyte membrane for a fuel cell of this form is reinforced with a porous reinforcing layer in the peripheral region, so that the peripheral region is reinforced with higher strength than the power generation region by increasing the density of the porous reinforcing layer in the peripheral region. To do. And the electrolyte membrane for fuel cells of the said form suppresses the water | moisture content to the pore of the porous reinforcement layer in the said area | region by making a peripheral area | region high density. Therefore, since the moisture in the membrane of the electrolyte membrane is reduced, swelling due to moisture in the membrane can be reduced. As a result, according to the electrolyte membrane for a fuel cell of the above aspect, membrane damage can be avoided or suppressed with high effectiveness even in the peripheral region of the electrolyte membrane. And durability is also increased by avoiding or suppressing film damage.

  (2) In the electrolyte membrane for a fuel cell according to the above aspect, the porous reinforcing layer may be provided inside the electrolyte membrane or on both membrane surfaces. By doing so, the effectiveness of avoiding or suppressing membrane damage of the electrolyte membrane is further enhanced.

  (3) According to another aspect of the present invention, a membrane electrode assembly for a fuel cell is provided. This fuel cell membrane electrode assembly comprises electrode catalyst layers joined to both membrane surfaces of the electrolyte membrane of any one of the above forms. According to this form of membrane electrode assembly for fuel cells, membrane damage of the electrolyte membrane can be avoided or suppressed with high effectiveness even in the peripheral region, so that the durability of the membrane electrode assembly itself is enhanced. be able to.

  (4) According to another aspect of the present invention, a method for producing an electrolyte membrane for a fuel cell is provided. In this method of manufacturing an electrolyte membrane for a fuel cell, a porous reinforcing body having a first portion corresponding to a power generation region of the electrolyte membrane and a second portion corresponding to a peripheral region of the electrolyte membrane surrounding the power generation region is prepared. A step (1), a step (2) of forming a laminate by superimposing the porous reinforcing body on one membrane surface and the other membrane surface of the electrolyte membrane, and pressurizing the laminate while heating. By crushing the pores of the second part in the porous reinforcing body to increase the density of the second part, the electrolyte of the electrolyte membrane is placed in the pores of the porous reinforcing body. And melt impregnation step (3). In the method for manufacturing an electrolyte membrane for a fuel cell of the above form, in obtaining the electrolyte membrane reinforced by the porous reinforcing layer, the second portion of the porous reinforcing body corresponding to the peripheral region of the electrolyte membrane surrounding the power generation region is provided. The thickness of the reinforcing body is made larger than that of the first portion corresponding to the power generation region, and the porous reinforcing layer is formed at a high density in the peripheral region of the electrolyte membrane by subsequent formation of the laminated body and pressurization while heating the laminated body. An electrolyte membrane for a fuel cell having high strength and low water content can be easily provided. For this reason, according to the manufacturing method of the electrolyte membrane for fuel cells of the said form, even if it exists in the peripheral area | region of an electrolyte membrane, a membrane damage can be avoided or suppressed and a highly durable electrolyte membrane can be provided easily.

  (5) In the method for manufacturing an electrolyte membrane for a fuel cell according to the above aspect, in the step (1), porous reinforcement having the first portion and an extending portion extending outward from a peripheral edge of the first portion. A body member is prepared, and the porous reinforcement body in which the extension portion of the reinforcement member is bent to form the second portion can be prepared. In this way, a porous reinforcing body in which the thickness of the reinforcing member at the second part is larger than that of the first part can be obtained by a simple method of bending the extended part. For this reason, also by the manufacturing method of the electrolyte membrane for fuel cells of this form, the electrolyte membrane for fuel cells provided with the high-density porous reinforcement layer as mentioned above in the peripheral region of an electrolyte membrane can be provided easily. In addition, since the second part is formed by bending the extension part, the positional deviation between the first part and the second part hardly occurs. Therefore, according to the manufacturing method of the electrolyte membrane for fuel cells of this form, the electrolyte membrane for fuel cells in which the shape of the power generation region is arranged can be easily provided.

  (6) In the method for manufacturing an electrolyte membrane for a fuel cell according to the above aspect, in the step (1), a planar porous first reinforcing member corresponding to the first part and the second part, Preparing a frame-like porous second reinforcing member corresponding to the second part, and stacking the second reinforcing member on the first reinforcing member, the first part and the second part; The porous reinforcing body having the above can be prepared. In this way, a porous reinforcing body in which the thickness of the reinforcing member at the second part is larger than that of the first part can be obtained by a simple method of stacking the first reinforcing member having a planar shape and the second reinforcing member having a frame shape. Can be obtained. For this reason, also by the manufacturing method of the electrolyte membrane for fuel cells of this form, the electrolyte membrane for fuel cells provided with the high-density porous reinforcement layer as mentioned above in the peripheral region of an electrolyte membrane can be provided easily. In addition, since the second part has a frame shape, the power generation region is determined by the frame shape. Therefore, also by the manufacturing method of the electrolyte membrane for fuel cells of this form, the electrolyte membrane for fuel cells with which the shape of the electric power generation area was prepared can be provided easily. In addition, since the planar first reinforcing member and the frame-like second reinforcing member can be prepared in the form of a long film, the first and second reinforcing members in the form of a film to the electrolyte membrane in the form of a film. By laminating the members, an electrolyte membrane for a fuel cell can be continuously produced, and productivity can be improved.

  In the present invention, the membrane / electrode assembly having the fuel cell electrolyte membrane obtained in the above-described form may be sandwiched between the gas diffusion layers on both sides thereof and then sandwiched between the separators. By so doing, the present invention can also be applied as a membrane electrode assembly having a gas diffusion layer and a manufacturing method thereof, or a manufacturing method of a fuel cell.

It is explanatory drawing which shows schematic structure of the fuel cell 10 as one Embodiment of this invention. 2 is an explanatory diagram showing a schematic configuration of a single cell 40 in plan view. FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 2. FIG. 4 is a sectional view taken along line 4-4 in FIG. It is process drawing which shows the manufacture procedure at the time of manufacturing the fuel cell 10 through manufacture of MEA and MEGA. It is process drawing which shows the detail of the manufacturing procedure of MEA in process S100. It is explanatory drawing which shows the outline and the mode of arrangement | positioning of the electrolyte precursor resin sheet 41zs and two pairs of porous reinforcement sheet | seats 41p to prepare. It is explanatory drawing which shows typically the mode of the process in each process from process S120. It is a graph which shows the mode of the moisture content in the peripheral area | region site | part 141f and the center area | region site | part 141c of the electrolyte membrane 41 of this embodiment. It is a graph which shows the relationship between the number of wet and dry cycles and gas permeation amount (Pa / s) about the electrolyte membrane 41 of this embodiment. It is explanatory drawing explaining the mode of preparation of the porous reinforcement body sheet | seat 41p in other embodiment, and the mode of formation of the laminated body 41S. It is explanatory drawing explaining the mode of preparation of the porous reinforcement body sheet | seat in another embodiment, and the mode of formation of the laminated body 41S. It is explanatory drawing which shows the mode of formation of the porous 2nd sheet | seat film 41p2f. It is explanatory drawing which shows roughly the mode of manufacture of the electrolyte membrane 41 in other embodiment by a film form. It is explanatory drawing which shows typically the mode of the process in each process from process S120 in embodiment which changed the mode of lamination | stacking of the porous 1st sheet | seat 41p1 and the porous 2nd sheet | seat 41p2. It is explanatory drawing which shows other embodiment of the porous reinforcement body sheet | seat 41p.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is an explanatory diagram showing a schematic configuration of a fuel cell 10 as an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a schematic configuration of a single cell 40 in plan view, and FIG. 3 is a line 3-3 in FIG. 4 is a sectional view taken along line 4-4 in FIG.

  The fuel cell 10 has a stack structure in which a plurality of single cells 40 that generate power by an electrochemical reaction between hydrogen and oxygen are stacked and sandwiched between a pair of end plates 10a as shown in FIG. The stack structure of the single cells 40 is referred to as a fuel cell stack 40S. When the fuel cell stack 40S is sandwiched between a pair of opposed end plates 10a, an insulating plate 20a, a front end side terminal plate 31, and a rear end side terminal plate 32 are interposed on the end plate 10a side, respectively. The fuel cell 10 includes an air supply port 12IN, an air exhaust port 12OUT, a hydrogen supply port 14IN, a hydrogen exhaust port 14OUT, a cooling water supply port 16IN, and a cooling air in the front end side end plate 10a, the insulating plate 20a, and the front end side terminal plate 31. It has a water outlet 16OUT.

  The end plate 10a is formed of a metal such as steel in order to ensure rigidity. The insulating plate 20a is formed of an insulating member such as rubber or resin. The front end side terminal plate 31 and the rear end side terminal plate 32 are formed of a gas impermeable conductive member such as dense carbon or a copper plate.

  The fuel cell 10 includes a fastening shaft 100 disposed on the side of the fuel cell stack 40S between a pair of opposed end plates 10a. The fastening shaft 100 is fixed in contact with the end plate 10a by a bolt 102, thereby fastening the fuel cell stack 40S described above between a pair of opposed end plates 10a.

  As shown in FIGS. 3 to 4, each single cell 40 constituting the fuel cell stack 40 </ b> S includes an electrolyte membrane 41, an anode 42, and a cathode 43. The electrolyte membrane 41 is formed as described later using a solid polymer electrolyte resin, for example, a fluorine resin, has proton conductivity, and exhibits good electrical conductivity in a wet state. The anode 42 and the cathode 43 are electrode catalyst layers formed by coating conductive particles carrying a catalyst such as platinum or platinum alloy, for example, carbon particles with an ionomer having proton conductivity. Usually, the ionomer is a polymer electrolyte resin (for example, a fluororesin) that is a solid polymer material of the same quality as the electrolyte membrane 41, and has proton conductivity due to its ion exchange group. The electrolyte membrane 41 constitutes a membrane electrode assembly (MEA) together with the anode 42 and the cathode 43 joined to both membrane surfaces. The MEA is sandwiched between an anode-side gas diffusion layer 44 and a cathode-side gas diffusion layer 45 having gas diffusion permeability to form a MEGA (Membrane-Electrode & Gas. Diffusion Layer Assembly). The single cell 40 holds the MEGA with a frame-like frame 50 and sandwiches the MEGA with the separator 46 and the separator 47 together with the frame. As shown in FIG. 2, the single cell 40 has a MEA central region corresponding to an in-frame region of the frame 50 as a power generation region 41 gp and surrounds the region with a peripheral region 41 sp. The separator 46 includes a hydrogen flow path 46 a as a fuel gas to be supplied to the anode 42 and a cooling water flow (not shown), and the separator 47 is illustrated with an air flow path 47 a as an oxidant gas to be supplied to the cathode 43. A cooling water flow path that does not. The number of single cells 40 in the fuel cell stack 40S can be arbitrarily set according to the output required for the fuel cell 10.

  As shown in FIG. 2, the unit cell 40 includes a separator 46, a separator 47, and a frame 50, an in-side air manifold 401, an out-side air manifold 402, an in-side hydrogen manifold 403, an out-side hydrogen manifold 404, and an in-side cooling water. A manifold 405 and an out side cooling water manifold 406 are provided. Each manifold on the in side is connected to an in side supply port such as an air supply port 12IN of the end plate 10a, and each manifold on the out side is connected to an out side exhaust port such as an air exhaust port 12OUT of the end plate 10a. . The single cell 40 guides the air flowing from the in-side air manifold 401 through the air supply port 12IN of the end plate 10a to the flow path 47a of the separator 47 from the peripheral flow path 401r, and over the power generation region 41gp, the MEGA To the cathode 43. The single cell 40 also guides the hydrogen gas flowing from the in-side hydrogen manifold 403 of the end plate 10a to the flow path 46a of the separator 46 via the peripheral flow path 403r, and to the anode 42 of the MEGA over the power generation region 41gp. Supply. The single cell 40 generates electricity by such gas supply.

  Further, the single cell 40 guides excess air from the power generation region 41gp to the out-side air manifold 402 via the peripheral flow path 402r, and discharges the excess air out of the cell from the air exhaust port 12OUT of the end plate 10a. The single cell 40 guides surplus hydrogen gas from the power generation region 41gp to the out-side hydrogen manifold 404 through the peripheral flow path 404r, and discharges the hydrogen gas out of the cell from the hydrogen exhaust port 14OUT of the end plate 10a. As for the cooling water, the single cell 40 guides the cooling water flowing from the cooling water supply port 16IN of the end plate 10a to a cooling water passage (not shown) of the separator 46 and the separator 47, and the cooling water is supplied to the out side cooling water manifold 406. And it guide | induces out of a cell through the cooling water discharge port 16OUT of the end plate 10a. The cooling water guided outside the cell circulates and is guided to the single cell 40 again.

  Next, the electrolyte membrane 41 will be described in detail. As shown in FIGS. 3 to 4, the electrolyte membrane 41 constituting the MEA is an electrolyte membrane with a reinforcing layer, and anodes are provided on both sides of an electrolyte membrane portion 41 c made of an electrolyte resin (fluorine resin) having proton conductivity. A side reinforcing layer 41an and a cathode side reinforcing layer 41ca are provided. The anode 42 is formed to be joined to the anode side reinforcing layer 41an, and the cathode 43 is formed to be joined to the cathode side reinforcing layer 41ca, thereby forming an MEA. Further, an anode-side gas diffusion layer 44 is formed on the anode 42 of the MEA, and a cathode-side gas diffusion layer 45 is formed on the cathode 43 to form a MEGA.

  Both the anode side reinforcing layer 41an and the cathode side reinforcing layer 41ca are porous bodies formed by stretching polytetrafluoroethylene (PTFE) to make it porous, and an electrolyte resin is contained in the pores. Contains via melt impregnation. Then, both the reinforcing layers described above have a density by changing the porosity between the central region portion 141c corresponding to the power generation region 41gp and the peripheral region portion 141f surrounding the central region portion 141c in the plan view shown in FIG. A difference is provided so that the peripheral region portion 141f has a higher density than the central region portion 141c. A method for providing such a density difference will be described later. The central region 141c is narrower than the power generation region 41gp of FIG. 2 by an amount corresponding to the inner edge region 141ff on the periphery of the anode 42 and the cathode 43 shown in FIGS. However, since the inner edge side region 141ff is about 0.1 to 10 mm and is slightly shorter than the length of each side of the power generation region 41gp, the central region portion 141c of both the reinforcing layers is substantially the power generation region 41gp. Is almost the same. Further, even in the peripheral region portion 141f of both the reinforcing layers, it is almost the same as the peripheral region 41sp of FIG.

  When the single cell 40 holds the above MEGA in the frame 50, the peripheral region 141 f of the electrolyte membrane 41 is joined to the frame 50 in the outer peripheral side region 141 fC outside the inner peripheral side region 141 ff. The unit cell 40 hermetically adheres and holds the MEA having the electrolyte membrane 41, and thus the MEGA, with the adhesive force of the adhesive applied to the joining region.

  Next, the manufacturing procedure of the fuel cell 10 will be described. FIG. 5 is a process diagram showing a manufacturing procedure when the fuel cell 10 is manufactured through the manufacture of MEA and MEGA. As shown in the figure, in the manufacture of the fuel cell 10, the MEA is manufactured (step S100), the MEGA components are prepared (step S200), the MEGA is manufactured (step S300), and the unit cell 40 is manufactured (step S400). Through the stacking and assembling (step S500), the fuel cell 10 including the fuel cell stack 40S is manufactured. Hereinafter, each step will be described in detail.

FIG. 6 is a process diagram showing details of the MEA manufacturing procedure in step S100. As shown in the drawing, in manufacturing the MEA, first, an electrolyte precursor resin sheet 41zs and two pairs of porous reinforcing sheet 41p, which will later become the electrolyte membrane 41, are prepared (step S110). FIG. 7 is an explanatory view showing an outline and a state of arrangement of the prepared electrolyte precursor resin sheet 41zs and two pairs of porous reinforcing sheet 41p. The electrolyte precursor resin sheet 41zs is a rectangular sheet using an electrolyte precursor resin (hereinafter referred to as “F-type electrolyte resin”) whose side chain terminal group is a sulfonic acid group precursor (—SO ₂ F). It is a molded product molded to make This F-type electrolyte resin can be made of, for example, Nafion manufactured by DuPont (Nafion is a registered trademark, the same applies hereinafter), and is performed in a wet state by performing ion conduction treatment by a conventionally known hydrolysis treatment or the like by a process described later. Proton proton conductivity.

  The porous reinforcing sheet 41p includes a porous first sheet 41p1 and a porous second sheet 41p2. The porous first sheet 41p1 and the porous second sheet 41p2 are both porous sheets made by using a sliver obtained by stretching PTFE. In the stage of the preparation step shown in FIG. % Porosity. The porous first sheet 41p1 has the same planar view shape as the electrolyte precursor resin sheet 41zs. The porous second sheet 41p2 has a frame shape whose outer shape in plan view is the same as that of the electrolyte precursor resin sheet 41zs. The frame width of the porous second sheet 41p2 is the width of the peripheral region portion 141f shown in FIGS. 3 to 4, that is, the combined width of the inner peripheral region 141ff and the outer peripheral region 141fC. And the porous reinforcement body sheet | seat 41p comprised by overlapping the porous 2nd sheet | seat 41p2 on the porous 1st sheet | seat 41p1 is the area | region which occupies the frame of the porous 2nd sheet | seat 41p2 only for the porous 1st sheet | seat 41p1. The thickness of the frame portion of the porous second sheet 41p2 is set such that the porous first sheet 41p1 and the porous second sheet 41p2 overlap each other, and the thickness of the reinforcing body is made different.

The porous reinforcing sheet 41p thus prepared is arranged on both surfaces of the electrolyte precursor resin sheet 41zs to form a laminate 41S (step S120). When the porous reinforcing sheet 41p is arranged, the porous first sheet 41p1 is overlapped with the electrolyte precursor resin sheet 41zs as indicated by an arrow in FIG. FIG. 8 is an explanatory view schematically showing the state of processing in each step from step S120. Subsequent to step S120, the stacked body 41S is pressurized while being heated (step S130). In this step S130, as shown in FIG. 8, first, the laminate 41S is set between an upper mold Pu and a lower mold Pd (not shown) of a hot press apparatus (step S130a). Then, while heating the laminate 41S at a predetermined temperature (e.g. 170 ° C. to 280 ° C.), pressurized with a predetermined pressure (e.g., ^{4N / cm 2 ~30N / cm 2} ) ( step S130b~S130c). In addition, it is good also as a structure which replaces with heating and pressurization with such a hot press method, and heats and pressurizes with other methods, such as a hot roll press.

  The layered body 41S that is heated and pressurized in step S130 is a molded product of F-type electrolyte resin and is porous on both sides of a solid electrolyte precursor resin sheet 41zs that does not have bubbles. Specifically, it includes a porous first sheet 41p1 and a porous second sheet 41p2. The frame-like porous second sheet 41p2 is in contact with the mold surface so as to overlap the porous first sheet 41p1. Due to the relationship between the properties of the sheet body and the sheet arrangement, the porous second sheet 41p2 is compressed in the heating / pressurizing step, and the peripheral area of the porous first sheet 41p1 is also compressed while being compressed. Compress. Thus, the previously compressed portion is the peripheral region portion 141f described above, and the peripheral surface portion 141f is such that the sheet surface on the mold surface side of the porous second sheet 41p2 becomes the porous first sheet as pressurization proceeds. It is compressed until it becomes flush with 41p1. Thereby, the peripheral region part 141f is compressed to the thickness of the porous first sheet 41p1 in the central region part 141c so that the overlapping thickness of the peripheral region of the porous first sheet 41p1 and the porous second sheet 41p2 is increased (step). S130b). Since both of the first and second sheets are porous, the pores are crushed by compression, so that the peripheral region portion 141f has a higher density than the central region portion 141c of the porous first sheet 41p1 alone. It becomes. Even if the pores are crushed in this way, the porous first sheet 41p1 and the porous second sheet 41p2 in the peripheral region portion 141f remain porous.

  Simultaneously with the start of pressurization in step S130b or after the start of pressurization, the stacked body 41S is pressed while being heated at the above-described temperature while being set on the upper mold Pu and the lower mold Pd. Thereby, F type electrolyte resin of the electrolyte precursor resin sheet 41zs which comprises the laminated body 41S fuse | melts. The molten F-type electrolyte resin is impregnated in the pores of the porous first sheet 41p1 and the porous second sheet 41p2 in the peripheral region portion 141f and the central region portion 141c by receiving capillary pressure and pressurization. The laminated body 41S is further compressed by reducing the height of the laminated body as the F-type electrolyte resin is impregnated into the pores so that the central region portion 141c and the peripheral region portion 141f that face each other approach each other (step S130c). The stack height in this step S130c is the final thickness of the electrolyte membrane 41. Even in this state, the porous first sheet 41p1 and the porous second sheet 41p2 remain porous.

  The molten F-type electrolyte resin finally has an electrolyte precursor resin sheet 41zs and a porous structure because of its polymer structure and the property of enhancing intermolecular bonding by melt kneading while being subjected to pressure shear. In the interface with the first sheet 41p1 and the interface between the porous first sheet 41p1 and the porous second sheet 41p2 in the peripheral region portion 141f, the above two members sandwiching the interface are interfaced with each other via the F-type electrolyte resin. Combine. Such interfacial bonding results in the following bonding.

  By pressing, heating, melting, and impregnating the electrolyte precursor resin sheet 41zs made of F-type electrolyte resin having no air bubbles between the porous reinforcement sheet 41p on both sides thereof, the porous reinforcement sheet 41p The F-type electrolyte resin of the electrolyte precursor resin sheet 41zs is integrated with the F-type electrolyte resin impregnated in the pores of the interface, and is bonded to the electrolyte precursor resin sheet 41zs through cooling of the thermoplastic F-type electrolyte resin. . This bond is in a stable state without leaving stress at the interface, and sufficient interface bond stability can be ensured. In addition, since the F-type electrolyte resin has high heat resistance, thermal degradation does not occur in the heating and pressurizing step.

  The F-type electrolyte resin melted in step S130c is impregnated into the pores of the sheet surface 141s of the porous first sheet 41p1 and the porous second sheet 41p2 on the mold surface side of the upper mold Pu and the lower mold Pd. . The sheet surface 141s before the resin impregnation has a striped sliver when the porous both sheets are formed. However, since the F-type electrolyte resin impregnated in the pores of the sheet surface 141 s covers the exposed sliver, the sheet surface 141 s is almost free from fluff.

  By the way, the compression of the laminated body 41S accompanying the pressurization of the laminated body 41S by the upper mold Pu and the lower mold Pd in step S130c shown in FIG. 8 is performed in the process of melting the F-type electrolyte resin of the electrolyte precursor resin sheet 41zs. The That is, since the laminate 41S is compressed while the electrolyte precursor resin sheet 41zs is in the form of a solid sheet, the porous first sheet 41p1 in the central region portion 141c is also compressed so that the pores are crushed to some extent. In this case, the degree of collapse of the pores in the peripheral region portion 141f is smaller than that in the central region portion 141c because the portion has already been compressed (step S130b). For this reason, as shown in the drawing, the peripheral region portion 141f enters the electrolyte precursor resin sheet 41zs side from the central region portion 141c. The pressure and compression of the laminated body 41S are matched with the melting of the F-type electrolyte resin of the electrolyte precursor resin sheet 41zs, so that the peripheral region portion 141f is made the electrolyte precursor resin to the same extent as the central region portion 141c. You may make it enter into the sheet | seat 41zs side.

  Following the step S130 shown in FIG. 6, specifically, following the step S130c of FIG. 8, the laminated body 41S is removed from the mold, and the laminated body 41S is subjected to a conventionally known hydrolysis treatment and then cured. (Step S140) By this hydrolysis treatment, the F-type electrolyte resin contained in the laminate 41S has proton conductivity. Through the steps from S100 to S140, the electrolyte membrane 41 shown in FIGS. 3 to 4 is obtained as a finished product of the electrolyte membrane for a fuel cell. Then, through the steps S100 to S140, the prepared porous reinforcing sheet 41p is in a state in which the pores are impregnated with the F-type electrolyte resin after the peripheral region portion 141f is densified. The electrolyte precursor resin sheet 41zs prepared by transitioning to the anode-side reinforcing layer 41an and the cathode-side reinforcing layer 41ca that reinforces the 41 is prepared by the F-type electrolyte resin forming the same, the anode-side reinforcing layer 41an and the cathode-side reinforcing layer 41ca. Through the hydrolysis treatment with the F-type electrolyte resin impregnated in the pores, transition is made to the electrolyte membrane portion 41c and the electrolyte membrane 41 having proton conductivity. Said embodiment which manufactures the electrolyte membrane 41 by the process from this process S100 to process S140 will comprise one form of the following manufacturing procedure. That is, when forming the laminated body 41S by stacking the porous reinforcing body sheet 41p, which is a porous reinforcing body, the prepared porous reinforcing body is an electrolyte precursor film formed from an electrolyte precursor that changes to an electrolyte. The laminated body 41S is formed so as to overlap the one film surface and the other film surface of the electrolyte precursor resin sheet 41zs. Next, the electrolyte precursor is changed to an electrolyte during the heating / pressurizing process of the stacked body 41S or after the heating / pressurizing process of the stacked body.

  The electrolyte membrane 41 obtained in step S140 can be shipped to another MEA production line or MEA production plant, another MEGA production line or MEGA production plant, or another fuel cell production line or production plant (step S145). ). In this embodiment, in order to manufacture the MEA, the MEA is manufactured by forming the electrode catalyst layers of the anode 42 and the cathode 43 on both membrane surfaces of the electrolyte membrane 41 obtained in step S140 (step S150), and FIG. The process proceeds to the next step S200. The MEA obtained in step S150 can be shipped to another MEGA production line or MEGA production factory, or another fuel cell production line or production factory (step S145).

  In step S200 of FIG. 5, constituent members of MEGA except MEA, specifically, anode-side gas diffusion layer 44, cathode-side gas diffusion layer 45, and frame 50 are prepared. Next, the MEA obtained in step S100 is sandwiched between the anode side gas diffusion layer 44 and the cathode side gas diffusion layer 45, and the MEA is held on the frame 50 to manufacture MEGA (step S300). When the MEA is sandwiched between the two gas diffusion layers, the MEA and the gas diffusion layer are joined by a technique such as hot pressing. Further, when the MEA is held by the frame 50, an adhesive is applied to the joint surface between the MEA and the frame 50, and the MEA is bonded and held to the frame 50. The MEGA obtained in this manner can be shipped to other fuel cell production lines or production plants (step 310).

  Next, the single cells 40 are produced by sandwiching the MEGA obtained in step S300 between the separator 46 and the separator 47 (step S400), and the predetermined number of single cells 40 are combined with the front end side terminal plate 31 and the rear end side terminal plate. 32 and the insulating plate 20a are stacked between the end plates 10a shown in FIG. 1 and assembled into a stack, and are fastened in the stacking direction with a predetermined fastening force (step S500). Thereby, the fuel cell 10 shown in FIG. 1 is obtained.

  Next, the property and performance of the electrolyte membrane 41 of the present embodiment configured as described above will be described. FIG. 9 is a graph showing the water content in the peripheral region 141f and the central region 141c of the electrolyte membrane 41 of the present embodiment. In FIG. 9, the vertical axis is the water content (%) obtained by dividing the weight at the time of water content by the weight at the time of drying, and this water content is plotted for the peripheral region region 141 f and the central region region 141 c. In measuring the water content, the electrolyte membrane 41 is cut into a peripheral region portion 141f and a central region portion 141c, and each portion is immersed in hot water at 100 ° C. for 1 hour to wipe off surface moisture. The weight was measured at room temperature (25 ° C.), and this was regarded as the weight when containing water. Next, both the above parts were placed in a temperature environment of 80 ° C. and dried for 2 hours, and the weight was measured at room temperature (25 ° C.). Then, the water content of both the above parts was determined, and FIG. 9 was obtained. As shown in the figure, in the electrolyte membrane 41 of the present embodiment, the moisture content in the central region portion 141c is increased by reinforcing the porous membrane sheets 41p on both membrane surfaces of the electrolyte membrane so that the anode-side reinforcing layer 41an and the cathode It can be made smaller than the electrolyte membrane not provided with the side reinforcing layer 41ca. In addition, in the electrolyte membrane 41 of the present embodiment, the peripheral region portion 141f has a higher density than the central region portion 141c when reinforcing the porous membrane sheets 41p on both membrane surfaces of the electrolyte membrane. The water content of the region part 141f is reduced to about 30% of the central region part 141c. Therefore, according to the electrolyte membrane 41 of the present embodiment, in the peripheral region portion 141f and the central region portion 141c, the moisture in the membrane of the electrolyte membrane 41 is reduced by the moisture in the membrane during the power generation operation process of the fuel cell 10. Since swelling can be reduced, film damage can be avoided or suppressed with high effectiveness not only in the central region portion 141c but also in the peripheral region portion 141f. In this case, since the anode-side reinforcing layer 41an and the cathode-side reinforcing layer 41ca are made of PTFE porous bodies having water repellency, the water content in the electrolyte membrane 41 is further reduced. This is beneficial for avoiding and suppressing membrane damage.

  FIG. 10 is a graph showing the relationship between the number of dry and wet cycles and the gas permeation amount (Pa / s) for the electrolyte membrane 41 of the present embodiment. The horizontal axis of the graph indicates the number of wet and dry cycles, and the vertical axis indicates the gas permeation amount. From FIG. 10, the existing electrolyte membrane without a reinforcing layer can suppress gas permeation while the number of wet and dry cycles is small. However, as the number of dry and wet cycles increases, the amount of gas permeation rapidly increases, so that cross leak occurs. To do. On the other hand, in the electrolyte membrane 41 of the present embodiment, even if the number of cycles increases more than the number of dry and wet cycles in which the gas permeation amount suddenly increased in the existing electrolyte, the gas permeation amount does not rapidly increase. From this, according to the electrolyte membrane 41 of this embodiment, durability can be improved without causing membrane damage also from the result of FIG. In order to avoid such membrane damage and improve the durability, in addition to reinforcing the electrolyte membrane 41 with the porous reinforcing sheet 41p on both membrane surfaces, the peripheral region 141f has a high density, so that the central region This can be achieved by reinforcing the peripheral region portion 141f with higher strength than the portion 141c. That is, as shown in FIG. 3, for the convenience of supplying gas to the cathode 43 through the peripheral flow path 401r, only the electrolyte membrane 41 is present alone, so that the expansion / extension / expansion is repeated in the peripheral region portion 141f. Although film damage is feared, film damage of the peripheral region part 141f can be avoided with high effectiveness by increasing the density and strength of the peripheral region part 141f. Since the electrolyte membrane 41 has high durability, the durability of the MEA, MEGA, single cell 40 and fuel cell 10 using the electrolyte membrane 41 can also be enhanced.

  Further, in the electrolyte membrane 41 of the present embodiment, the electrolyte precursor via the F-type electrolyte resin impregnated in the pores of the porous reinforcing sheet 41p at the interface between the porous reinforcing sheet 41p and the electrolyte precursor resin sheet 41zs. The resin sheet 41zs is integrally bonded with the F-type electrolyte resin. This bond is in a stable state without leaving stress at the interface, and sufficient interface bond stability can be ensured. Therefore, between the electrolyte membrane portion 41c where the electrolyte precursor resin sheet 41zs has transitioned and the anode side reinforcing layer 41an by the porous reinforcing sheet 41p, and between the electrolyte membrane portion 41c and the cathode side reinforcing layer 41ca, the fuel Differences in expansion / contraction due to the power generation operation of the battery 10 are less likely to occur. As a result, there is an effect that distortion generated in the surface direction in the electrolyte membrane 41 can be suppressed. Further, by suppressing the distortion in the surface direction, peeling and breakage between the electrolyte membrane portion 41c and the anode side reinforcing layer 41an and between the electrolyte membrane portion 41c and the cathode side reinforcing layer 41ca can be prevented.

  Further, also at the interface between the peripheral region portion 141f and the central region portion 141c, the F-type electrolyte resin impregnated in the pores of the porous reinforcing member sheet 41p in the central region portion 141c and the porous reinforcing member sheet in the peripheral region portion 141f. 41p and the interface bonding described above through the F-type electrolyte resin impregnated in the pores of the porous second sheet 41p2. For this reason, since the film damage between the peripheral region part 141f and the central region part 141c can be avoided with high effectiveness, the effectiveness of avoiding the film damage of the peripheral region part 141f also increases from this point.

  In the present embodiment, a porous method including a central region portion 141c and a thicker peripheral region portion 141f is obtained by a simple method of stacking a planar porous first sheet 41p1 and a frame-shaped porous second sheet 41p2. The quality reinforcement sheet | seat 41p can be obtained easily. In addition, since the central region portion 141c and thus the power generation region 41gp can be defined by the frame shape of the porous second sheet 41p2, the electrolyte membrane 41 having the shape of the power generation region 41gp can be easily provided.

  The electrolyte membrane 41 of the present embodiment has the following advantages due to its structural features. As shown in FIGS. 3 to 4, in the electrolyte membrane 41, the high-density / high-strength peripheral region portion 141 f includes an inner edge side region 141 ff on the central region portion 141 c side and an outer peripheral edge side region 141 fC on the outer side. For this reason, the outer peripheral side region 141fC held by the frame 50 can also have a high density and high strength, so that the strength of holding the electrolyte membrane 41 to the frame 50 can be increased. Further, the inner edge side region 141ff that extends from the outer peripheral side region 141fC that adheres and holds the electrolyte membrane 41 to the frame 50 to the central region portion 141c can be made to have a high density and high strength. The holding posture of the electrolyte membrane 41 can be maintained. As a result, the reliability of holding the electrolyte membrane 41 to the frame 50 can be enhanced. In this case, since the inner edge side area 141ff is about 0.1 to 10 mm, the central area portion 141c can be made substantially the same as the power generation area 41gp of FIG. In addition, since the pores are impregnated with the electrolyte also in the inner edge side region 141ff, the anode 42, the cathode 43, and the anode side gas diffusion layer 44 are formed in the inner edge side region 141ff as shown in FIGS. And the cathode side gas diffusion layer 45 are formed to overlap each other, the inner edge side region 141ff can be included in the power generation region 41gp.

  In addition, the electrolyte membrane 41 of the present embodiment has the peripheral region 141f and the central region 141c surrounded by the same having the same thickness (see FIG. 8). For this reason, since the electrolyte membrane 41 of this embodiment can be made the same as the existing electrolyte membrane in the outer shape, the substitution substitution with the existing electrolyte membrane becomes simple. Moreover, in the electrolyte membrane 41 of the present embodiment, the electrolyte is impregnated into the pores of the sheet surface 141 s so that the sheet surface 141 s is a sheet surface that is substantially free of blemishes. , Will not hinder.

  Next, another embodiment will be described. FIG. 11 is an explanatory diagram for explaining the preparation of the porous reinforcing sheet 41p and the formation of the laminated body 41S in another embodiment. This embodiment is characterized in that a porous reinforcing sheet 41p having a difference in reinforcing body thickness between the peripheral region portion 141f and the central region portion 141c is prepared from one large-sized porous reinforcing sheet 41ps. There is. As shown in the drawing, in this embodiment, a large-sized porous reinforcing sheet 41ps is prepared (step S110a). The large-sized porous reinforcing sheet 41ps is further extended from each side of the porous first sheet 41p1 described above, that is, from each side of the rectangular shape obtained by adding the peripheral region part 141f to the central region part 141c. An extended portion 141fy is provided that extends by 141f. Next, the corner portion 14cc of this large size porous reinforcing sheet 41ps is cut (step S110b). This cutting is performed along a central outline line 141ck that defines the outline of the central area portion 141c and a peripheral outline line 141L that defines the outline of the peripheral area portion 141f.

  Following such cutting, the extension part 141fy is folded toward the central region part 141c with the peripheral outline line 141L as a fold so that the end of each extension part 141fy overlaps the central outline line 141ck (step S110c). By this bending, a porous reinforcing body sheet 41p equivalent to the porous first sheet 41p1 and a frame-shaped porous second sheet 41p2 is formed. Therefore, the porous reinforcing body sheet 41p is used as an electrolyte precursor. Overlaying on both surfaces of the resin sheet 41zs (step S110d), the laminated body 41S is formed as described in FIG. 8 (step S120). Thereafter, the process proceeds to steps S130a to S130c described in FIG. 8, and the electrolyte membrane 41, MEA, MEGA, and fuel cell 10 are manufactured in the same manner as in the above-described embodiment.

  Also according to this embodiment, effects such as avoidance of damage to the electrolyte membrane 41 can be achieved. And in this embodiment, the porous reinforcement sheet 41p provided with the center area | region site | part 141c and the peripheral area | region area | region 141f thicker than this by the simple method of bending the extension part 141fy of the large size porous reinforcement sheet | seat 41ps. Can be easily obtained. For this reason, according to this embodiment, the electrolyte membrane 41 having a high density and high strength in the peripheral region portion 141f can be easily provided. In addition, the positional relationship between the central region portion 141c and the thicker peripheral region portion 141f is defined by the bending of the extended portion 141fy, and the positional displacement between the central region portion 141c and the peripheral region portion 141f hardly occurs. Therefore, according to the present embodiment, it is possible to easily provide the electrolyte membrane 41 in which the shape of the power generation region 41gp corresponding to the central region portion 141c is arranged.

  FIG. 12 is an explanatory diagram for explaining a state of preparing a porous reinforcing body sheet and a state of forming a laminated body 41S in another embodiment. This embodiment is characterized in that the electrolyte membrane and the porous reinforcing sheet are prepared in the form of a long film. In this embodiment, as shown in FIG. 12, the electrolyte precursor resin film 41zf in which the electrolyte precursor resin sheet 41zs described above is continuous, the porous first sheet film 41p1f in which the porous first sheet 41p1 is continuous, A porous second sheet film 41p2f having a continuous porous second sheet 41p2 is prepared. The electrolyte precursor resin film 41zf is formed into a film using an F-type electrolyte resin, and the porous first sheet film 41p1f is formed into a film by stretching PTFE to make it porous. FIG. 13 is an explanatory view showing a state of formation of the porous second sheet film 41p2f. As shown in the drawing, for the porous second sheet film 41p2f, first, a film made by stretching PTFE to be made porous is formed, and in this state, it is fed into the through-hole forming zone Hz. Next, the through-hole 141ch corresponding to the central region portion 141c is continuously formed in the porous second sheet film 41p2f by the through-hole forming upper mold HPu and the through-hole forming lower mold HPd. The formation pitch dh of the through holes 141ch at this time is set twice as large as the peripheral region portion 141f.

  Next, the porous second sheet film 41p2f having the through-hole 141ch and the porous first sheet film 41p1f are stacked on both sides of the electrolyte precursor resin film 41zf as shown in FIG. Thereby, the porous reinforcement sheet film 41pf composed of the porous second sheet film 41p2f and the porous first sheet film 41p1f is overlapped with the electrolyte precursor resin film 41zf to form a laminate film 41Sf. And this laminated body film 41Sf is set between the upper mold | type Pu and lower mold | type Pd of a hot press apparatus (process S130a), after that, it transfers to process S130b-S130c demonstrated in FIG. The electrolyte membrane 41, MEA, MEGA, and fuel cell 10 are manufactured in the same manner as the embodiment. In this case, the upper mold Pu and the lower mold Pd in this embodiment have a long shape so that the laminate film 41Sf can be pressed simultaneously at a number of locations. In addition, the laminate film 41Sf obtained in the form of a film after hydrolysis is cut at the central portion of the formation pitch dh shown in FIG. 13 to produce the electrolyte membrane 41.

  Also according to this embodiment, effects such as avoidance of damage to the electrolyte membrane 41 can be achieved. In this embodiment, the electrolyte membrane 41 can be continuously manufactured by stacking the porous first sheet film 41p1f and the porous second sheet film 41p2f on the electrolyte precursor resin film 41zf, thereby increasing productivity. it can.

  FIG. 14 is an explanatory view schematically showing a state of manufacturing the electrolyte membrane 41 in another embodiment in the form of a film. As shown in the figure, in this embodiment, the electrolyte precursor resin film 41zf, the porous first sheet film 41p1f, and the porous second sheet film 41p2f in which the through holes 141ch are formed are wound up, respectively. Prepare by winding on a roller. Then, the electrolyte precursor resin film roller 41zr to the electrolyte precursor resin film 41zf, the porous first sheet film roller 41p1r to the porous first sheet film 41p1f, and the porous second sheet film to the first pressing roller pair 110. The porous second sheet film 41p2f is sent out from the roller 41p2r, respectively. Since the first pressing roller pair 110 has a roller distance corresponding to the distance between the upper mold Pu and the lower mold Pd in step S130a described in FIG. 8, the laminated film described in FIG. 41Sf is formed (step S130a).

  The laminated film 41Sf formed in this way is conveyed to the hot press device 120. The heating press device 120 includes a second pressing roller pair 121, a third pressing roller pair 122, and a heating device 123. The second pressing roller pair 121 has a roller distance corresponding to the distance between the upper mold Pu and the lower mold Pd in step S130b described with reference to FIG. 8, and presses and presses the laminate film 41Sf. The third pressing roller pair 122 has a roller distance corresponding to the distance between the upper mold Pu and the lower mold Pd in step S130a described with reference to FIG. 8, and presses and presses the laminate film 41Sf. The heating device 123 heats the laminated film 41Sf being conveyed so that the F-type electrolyte resin is melted and the pores are impregnated. For this reason, the laminated body film 41Sf is a porous second sheet film at a location corresponding to the peripheral region portion 141f described above by the second pressing roller pair 121 at the press location P2 while being conveyed through the heating press device 120. After receiving 41p2f compression (step S130b), the F-type electrolyte resin is melted and impregnated into the pores by heating with the heating device 123, and the further compression described above by the three-pressing roller pair 122 at the pressing point P3. (Step S130c) is received. Next, the laminate film 41Sf is transported to the hydrolysis device 130 and undergoes hydrolysis treatment in the device. Thereby, the F-type electrolyte resin contained in the laminate film 41Sf has proton conductivity. Thereafter, the laminate film 41Sf is conveyed to the cutting zone Cz and cut into a rectangular shape by the cutting blade 140, whereby the electrolyte membrane 41 is produced.

  Also according to this embodiment, effects such as avoidance of damage to the electrolyte membrane 41 can be achieved. And in this embodiment, by lamination | stacking of the porous 1st sheet film 41p1f and the porous 2nd sheet film 41p2f to the electrolyte precursor resin film 41zf, and compression and a hydrolysis process by said each press roller pair, it is continuous. In addition, the electrolyte membrane 41 can be manufactured, and the productivity can be further increased.

  FIG. 15 is an explanatory view schematically showing a state of processing in each step from step S120 in the embodiment in which the state of lamination of the porous first sheet 41p1 and the porous second sheet 41p2 is changed. As illustrated, in this embodiment, the porous reinforcing sheet 41p is formed as the porous first sheet 41p1 so that the frame-shaped porous second sheet 41p2 is on the side of the electrolyte precursor resin sheet 41zs. And this porous reinforcement body sheet | seat 41p is laminated | stacked on both sides of the electrolyte precursor resin sheet 41zs, and the laminated body 41S is formed (process S120). Then, the laminated body 41S is set between the upper mold Pu and the lower mold Pd (step S130a), and thereafter, while heating the laminated body 41S at the predetermined temperature as described with reference to FIG. Then, pressurization is performed at the predetermined pressure described above (Steps S130b to S130c), and a hydrolysis process is performed (Step S140), and the electrolyte membrane 41 is produced.

  Also according to this embodiment, effects such as avoidance of damage to the electrolyte membrane 41 can be achieved. In this embodiment, the impregnation into the pores of the F-type electrolyte resin in steps S130b to S130c occurs first from the porous second sheet 41p2 that overlaps the electrolyte precursor resin sheet 41zs, and the porous first sheet 41p1. This occurs after the first sheet overlaps the electrolyte precursor resin sheet 41zs. As described above, the porous second sheet 41p2 has a high density due to the collapse of the pores together with the overlapping portions of the porous first sheet 41p1. In this case, since the porous second sheet 41p2 overlaps the electrolyte precursor resin sheet 41zs from the beginning and can be impregnated as described above, the F-type electrolyte resin into the pores of the porous second sheet 41p2 The impregnation surely occurs before the pores of the porous second sheet 41p2 are crushed or in the process of starting to be crushed. Therefore, according to the present embodiment, even in the peripheral region portion 141f where the pores are crushed and dense, the electrolyte is surely impregnated with the F-type electrolyte resin, so that the anode is included in the peripheral region portion 141f. 3 and FIG. 4 where the cathode 42 and the cathode 43 are formed can also be included in the power generation region.

  FIG. 16 is an explanatory view showing another embodiment of the porous reinforcing sheet 41p. In this embodiment, from one large-sized porous reinforcing body sheet 41ps, the peripheral area portion 141f and the central area portion 141c have different reinforcing body thicknesses, and then the long side peripheral area portion 141f and the short piece The peripheral region portion 141f is characterized in that the porous reinforcing member sheet 41p is prepared with a difference in the reinforcing member thickness. As shown in the drawing, in this embodiment, a large-sized porous reinforcing sheet 41ps is prepared (step S110a). The large-sized porous reinforcing body sheet 41ps is formed on the short piece side from each side of the porous first sheet 41p1 described above, that is, from each side of the rectangular shape obtained by adding the peripheral region portion 141f to the central region portion 141c. In addition, an extended portion 141fy for one of the peripheral region portions 141f is provided, and an extended portion 141fy for two of the peripheral region portions 141f is provided on the long side. Next, the corner portion 14cc of this large size porous reinforcing sheet 41ps is cut (step S110b). This cutting is performed along the central outline line 141ck that defines the outline of the central area portion 141c and the peripheral outline line 141L that defines the outline of the peripheral area portion 141f, and the extended portion 141fy is bent twice on the long side. On the short side, the extended portion 141fy is bent once and used for the lure.

  Following such cutting, the outer peripheral line 141L is folded so that the end of the extended part 141fy overlaps the central outline line 141ck on the short side and the two extended parts 141fy are folded and overlapped on the long side. As a crease, the extended portion 141fy is bent toward the central region portion 141c (step S110c1). Next, on the long side, the overlapping extended portion 141fy is bent again toward the central region portion 141c (step S110c2). The porous reinforcing body sheet 41p obtained by this bending has a peripheral edge region portion 141f on the short piece side with a thickness of two overlapping sheets, and a peripheral edge region portion 141f on the long side side has a thickness of three overlapping sheets. Prepare with. The porous reinforcing sheet 41p is overlapped on both surfaces of the electrolyte precursor resin sheet 41zs as described with reference to FIG. 11 to form a stacked body 41S as described with reference to FIG. 8 (step S120). Thereafter, the process proceeds to steps S130a to S130c described in FIG. 8, and the electrolyte membrane 41, MEA, MEGA, and fuel cell 10 are manufactured in the same manner as in the above-described embodiment.

  Also according to this embodiment, since the thickness of the reinforcing body is different between the peripheral region portion 141f and the central region portion 141c, effects such as avoiding damage to the electrolyte membrane 41 can be obtained as described above. In this embodiment, since the long-side peripheral region portion 141f is thicker than the short-side peripheral region portion 141f, the long-side peripheral region portion 141f of the electrolyte membrane 41 is higher in density and height than the short-piece peripheral region portion 141f. Strength. The long peripheral region 141f of the electrolyte membrane 41 has a wide range of stress due to the distortion of the electrolyte membrane, and is easily affected by the stress. However, according to this embodiment, the peripheral region portion 141f on the long side of the electrolyte membrane 41 is made to have higher density and high strength, so the effectiveness of avoiding or suppressing membrane damage at the peripheral region portion 141f on the long side is improved. Can be increased.

  The present invention is not limited to the above-described embodiment, and can be realized with various configurations without departing from the spirit of the present invention. For example, the technical features of the embodiments corresponding to the technical features in each embodiment described in the summary section of the invention are intended to solve part or all of the above-described problems, or part of the above-described effects. Or, in order to achieve the whole, it is possible to replace or combine as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

  In each of the above embodiments, in manufacturing the electrolyte membrane 41 reinforced with the anode-side reinforcing layer 41an and the cathode-side reinforcing layer 41ca, the electrolyte precursor resin sheet 41zs is formed from the F-type electrolyte resin, and the molten F-type electrolyte resin is used. However, an electrolyte resin sheet formed from the electrolyte resin in the sheet shape of the electrolyte precursor resin sheet 41zs may be used. In this case, the porous reinforcing body sheet 41p is arranged on both sides of the electrolyte resin sheet, the formation of the laminated body 41S described in FIG. 8 (step S120), and heating / pressurization of the laminated body 41S (steps S130a to S130c). And this is omitted for the hydrolysis treatment.

  Moreover, in each embodiment, although the porous reinforcement body sheet | seat 41p and the porous reinforcement body sheet | seat film 41pf were made into the porous body using PTFE, other than polymer PE (polyethylene), PP (polypropylene), a polyimide, etc. It is good also as a porous body of the porous high molecular resin. Further, the porosity of the porous first sheet 41p1 or the like does not have to be limited to 50% or more, and the porosity can be made smaller than this.

  In addition, in each embodiment, two porous reinforcing layers of the anode side reinforcing layer 41an and the cathode side reinforcing layer 41ca are provided, but a porous reinforcing layer may be provided on one of the anode side and the cathode side. . In this case, the thickness of the peripheral region portion 141f of the porous reinforcing layer is made to approach the thickness of the electrolyte membrane 41, and the central region portion 141c is also made thicker than that shown in FIG. It will be useful above.

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 10a ... End plate 12OUT ... Air exhaust port 12IN ... Air supply port 14OUT ... Hydrogen exhaust port 14IN ... Hydrogen supply port 14cc ... Corner part 16OUT ... Cooling water discharge port 16IN ... Cooling water supply port 20a ... Insulating plate 31 ... Front end side terminal plate 32 ... Rear end side terminal plate 40 ... Single cell 40S ... Fuel cell stack 41 ... Electrolyte membrane 41c ... Electrolyte membrane part 41ca ... Cathode side reinforcing layer 41an ... Anode side reinforcing layer 41p ... Porous reinforcing body sheet 41p1 ... Porous 1st sheet 41p2 ... Porous 2nd sheet 41p1f ... Porous 1st sheet film 41p2f ... Porous 2nd sheet film 41p1r ... Porous 1st sheet film roller 41p2r ... Porous 2nd sheet film roller 41S ... Laminate 41Sf ... product Body film 41 pf ... Porous reinforcing body sheet film 41 gp ... Power generation area 41 zf ... Electrolyte precursor resin film 41 ps ... Large size porous reinforcing body sheet 41 sp ... Peripheral area 41 zr ... Electrolyte precursor resin film roller 41 zs ... Electrolyte precursor resin sheet 42 ... Anode 43 ... Cathode 44 ... Anode-side gas diffusion layer 45 ... Cathode-side gas diffusion layer 46 ... Separator 46a ... Channel 47 ... Separator 47a ... Channel 50 ... Frame 100 ... Fastening shaft 102 ... Bolt 110 ... First pressure roller pair DESCRIPTION OF SYMBOLS 120 ... Heat press apparatus 121 ... 2nd press roller pair 122 ... 3rd press roller pair 123 ... Heating device 130 ... Hydrolysis apparatus 140 ... Cutting blade 141L ... Periphery outline 141c ... Central area | region part 141f ... Peripheral area | region part 141s ... Sea Surface 141fC ... Outer peripheral edge side area 141ch ... Through hole 141ff ... Inner edge side area 141ck ... Center outer line 141fy ... Extension part 401 ... In side air manifold 401r ... Rim edge channel 402 ... Out side air manifold 402r ... Rim edge channel 403 ... In Side hydrogen manifold 403r ... Peripheral channel 404 ... Out side hydrogen manifold 404r ... Peripheral channel 405 ... In side cooling water manifold 406 ... Out side cooling water manifold P1 ... Pressing point P2 ... Pressing point P3 ... Pressing point Pu ... Upper mold Pd ... Lower mold dh ... Formation pitch Hz ... Through hole formation zone Cz ... Cutting zone HPd ... Through hole formation lower mold HPu ... Through hole formation upper mold

Claims (6)

An electrolyte membrane for a fuel cell,
The porous reinforcement layer of one layer even without least consist of a sheet having a stretching pore, with while containing an electrolyte in the pores,
The electrolyte layer for a fuel cell, wherein the porous reinforcing layer has different densities in a power generation region of the electrolyte membrane and a peripheral region surrounding the power generation region, and the peripheral region is denser than the power generation region.   The electrolyte membrane for a fuel cell according to claim 1, wherein the porous reinforcing layer is provided inside the electrolyte membrane or on both membrane surfaces. A membrane electrode assembly for a fuel cell,
A membrane electrode assembly for a fuel cell, comprising an electrode catalyst layer bonded to both membrane surfaces of the electrolyte membrane according to claim 1. A method for producing an electrolyte membrane for a fuel cell, comprising:
Preparing a porous reinforcing body having a first portion corresponding to the power generation region of the electrolyte membrane and a second portion corresponding to the peripheral region of the electrolyte membrane surrounding the power generation region;
A step (2) of forming a laminate by superimposing the porous reinforcing body on one membrane surface and the other membrane surface of the electrolyte membrane;
By pressing the laminated body while heating, the pores of the second part in the porous reinforcing body are crushed to increase the density of the second part, and then the porous reinforcing body A step (3) of melting and impregnating the electrolyte of the electrolyte membrane in the pores;
A method for producing an electrolyte membrane for a fuel cell comprising: A method for producing an electrolyte membrane for a fuel cell according to claim 4,
In the step (1),
A porous reinforcing member having a first portion and an extending portion extending outward from a peripheral edge of the first portion is prepared, the extending portion of the reinforcing member is bent, and the second portion is bent. A method for producing an electrolyte membrane for a fuel cell, comprising preparing the porous reinforcing body having a portion formed thereon. A method for producing an electrolyte membrane for a fuel cell according to claim 4,
In the step (1),
Preparing a planar porous first reinforcing member corresponding to the first part and the second part, and a frame-shaped porous second reinforcing member corresponding to the second part; overlapping the second reinforcement member to said first reinforcement member, said preparing a porous reinforcing member, the manufacturing method of the electrolyte membrane for a fuel cell having said second portion and the first portion.

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