JP2015018662A - Unit cell structure, manufacturing method for unit cell and unit cell manufactured by that manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem of a conventional manufacturing method that a film is deformed when a membrane electrode assembly, having a frame made of a film, is bonded to other member.SOLUTION: A unit cell structure includes a membrane electrode assembly 2 having a frame 1, formed by sticking a plurality of plastic films 1A, on the periphery, a magnetic material 5 arranged on the frame 1, and separators 3, 4 on the anode side and cathode side for holding the frame 1 and membrane electrode assembly 2. Deformation of the frame 1 is prevented by enhancing the rigidity of the frame 1 by means of the magnetic material 5. Furthermore, deformation of the frame is prevented by giving a magnetic field for the magnetic material 5 during manufacture, thereby keeping the magnetic material 5 in the center of the unit cell C in the thickness direction.

Description

  The present invention relates to a single cell structure constituting a fuel cell, a method for manufacturing a single cell, and a single cell manufactured by the method, and further, a method for manufacturing a fuel cell stack formed by stacking the single cells, and a method for manufacturing the same. It relates to a fuel cell stack manufactured by

  As this type of single cell structure, for example, there is one described in Patent Document 1 under the name of a method for manufacturing a fuel cell. The fuel cell described in Patent Document 1 joins an electrolyte membrane and a reinforcing film having an opening for exposing the electrolyte membrane, and applies a catalyst to a portion exposed from the opening for exposing the electrolyte membrane to form a catalyst membrane. The reinforcing film is made of a material such as PEN, PET, or Teflon (registered trademark) PTPE.

  Thereafter, in the above fuel cell, the gas diffusion layer is joined to the reinforcing film of the catalyst membrane by hot press to form a membrane electrode assembly including the gas diffusion layer. In the above fuel cell, the membrane electrode assembly is sandwiched between a pair of gas flow path members to form a cell, and the cell and the separator are alternately stacked to form a fuel cell stack.

JP 2010-118237 A

  However, in the single cell structure manufactured by the conventional method of manufacturing a fuel cell as described above, the membrane electrode assembly has a reinforcing film integrally therearound. Therefore, there is a problem that the film may be deformed when bonded to another member, and as a result, the gas sealability may be impaired. It is a problem to solve such a problem. It was.

  The present invention has been made paying attention to the above-described conventional problems, and can prevent deformation of the frame in a single cell structure including a membrane electrode assembly having a frame made of a plastic film around it. It aims at providing the single cell manufactured by the single cell structure, the manufacturing method of the single cell, and its manufacturing method.

  A single cell structure according to the present invention includes a membrane electrode assembly having a frame formed by bonding a plurality of plastic films around, a magnetic body disposed on the frame, an anode side sandwiching the frame and the membrane electrode assembly, and The cathode side separator is provided, and the above configuration is used as means for solving the conventional problems.

  A method for producing a single cell according to the present invention comprises a membrane electrode assembly having a frame formed by laminating a plurality of plastic films, and an anode side and cathode side separator sandwiching the frame and the membrane electrode assembly. When manufacturing the provided single cell, a magnetic body is disposed between the plastic films, and the frame made of the plastic film and the membrane electrode assembly are integrated.

  Then, the manufacturing method of a single cell is as follows. (A) A membrane electrode assembly having a frame is laminated on the separator after applying an adhesive to the peripheral edge of the separator on either the anode side or the cathode side. ) After applying an adhesive to the peripheral edge of the frame, the other separator is laminated on the frame and membrane electrode assembly, and the thickness of the frame relative to the magnetic material after at least one of the steps (A) and (B) The magnetic field is applied in the direction, and the above structure is a means for solving the conventional problems.

  A single cell according to the present invention is a single cell manufactured by the above-described method for manufacturing a single cell, and includes a membrane electrode assembly having a frame formed by bonding a plurality of plastic films, a frame and a membrane. A separator is provided on the anode side and the cathode side for sandwiching the electrode assembly, and a magnetic material is disposed between plastic films forming the frame.

  Here, the magnetic substance is physically divided into three parts, ie, a diamagnetic substance, a paramagnetic substance, and a ferromagnetic substance, but usually indicates a ferromagnetic substance. In short, the magnetic body in the present invention may be any member that can be attracted by a magnet, and a ferromagnetic body or a paramagnetic body can be used. Specifically, a metal plate such as a steel plate or a metal fiber is used. Can be used.

  The single cell structure according to the present invention can prevent the deformation of the frame by increasing the rigidity of the frame by the magnetic material. In addition, the single cell structure can prevent the frame from being deformed by applying a magnetic field to the magnetic material during manufacturing and maintaining the magnetic material at the center in the thickness direction of the single cell.

  The method of manufacturing a single cell according to the present invention is to manufacture a single cell having a membrane electrode assembly having a frame made of a plastic film around it, while holding the magnetic body at the center in the thickness direction of the single cell. And the separator are bonded to each other, so that the deformation of the frame can be prevented.

  In addition, the unit cell manufactured by the above-described unit cell manufacturing method has a good frame without deformation, the thickness of the adhesive layer on both sides of the frame is uniform, and the sealing performance by the adhesive layer is also improved. To do.

It is the perspective view (A) explaining a fuel cell, and an exploded perspective view (B). It is a top view which shows a single cell in the decomposition | disassembly state. It is a top view (A) of a single cell explaining a 1st embodiment of the present invention, a sectional view (B) based on an AA line in Drawing A, and a section explanatory view (C) showing a formation process of a frame. . Sectional views (A) to (C) showing other examples of the steps of forming the frame and membrane electrode assembly, and sectional views (D) and (E) showing still other steps of forming the frame. It is sectional drawing (A)-(C) which shows the manufacturing process of the single cell in 1st Embodiment in order. It is a flowchart which shows the manufacturing process of the single cell in 1st Embodiment. It is a flowchart which shows the manufacturing process of the single cell in 2nd Embodiment. It is sectional drawing (A) which shows the fuel cell stack in 3rd Embodiment, and sectional drawing (B) which shows a pair of joined separator. It is a flowchart which shows the manufacturing process of the fuel cell stack in 3rd Embodiment. It is a flowchart which shows the manufacturing process of the fuel cell stack in 4th Embodiment. It is sectional drawing (A)-(D) which shows other embodiment of a magnetic body, respectively. It is a top view (A) which shows a single cell in a 5th embodiment, a sectional view (B) based on an AA line in Drawing A, and a sectional view (C) based on a BB line in Drawing A. It is sectional drawing which shows the fuel cell stack in 6th Embodiment.

  Hereinafter, based on the drawings, a single cell structure according to the present invention, a method for manufacturing a single cell, a single cell manufactured by the manufacturing method, a method for manufacturing a fuel cell stack, and a fuel cell stack manufactured by the manufacturing method The embodiment will be described.

  In the present invention, a single cell has, as a basic configuration, a membrane electrode assembly having a frame formed by laminating a plurality of plastic films, and an anode side and cathode side separator sandwiching the frame and the membrane electrode assembly. It is the structure provided with. The fuel cell stack is formed by stacking single cells having the above structure. Therefore, in the fuel cell stack of the present invention, for example, in a fuel cell provided with a large number of single cells in a stacked state, either a stacked body that is a part of all single cells or a stacked body that is all It becomes a target.

<First Embodiment>
The fuel cell FC shown in FIG. 1 has at least two or more cell modules M in which a plurality of single cells C are stacked and integrated with each other, as shown in FIG. And a seal plate P to be interposed. The single cell C and the seal plate P in the illustrated example have rectangular plate shapes having substantially the same vertical and horizontal dimensions. In FIG. 1B, two cell modules M and one seal plate P are shown, but in reality, a larger number of cell modules M and seal plates P are stacked.

  Further, in the fuel cell FC, end plates 56A and 56B are respectively disposed at both ends of the cell module M in the stacking direction, and fastening plates are disposed on the stacking end surfaces (upper and lower surfaces in FIG. 1) on the long side of the single cell C. 57A and 57B are provided, and reinforcing plates 58A and 58B are provided on the laminated end surface on the short side. Each of the fastening plates 57A, 57B and the reinforcing plates 58A, 58B has a size over the entire length in the stacking direction of the stacked body A composed of the cell module M and the seal plate P, and is connected to both end plates 56A, 56B by bolts (not shown). .

  In this way, the fuel cell FC has a case-integrated structure as shown in FIG. 1 (A). Each cell module M and the seal plate P are restrained and pressurized in the stacking direction so that each single cell C has a predetermined structure. Contact surface pressure is applied to maintain good gas sealing and electrical conductivity.

  As shown in FIG. 2, the single cell C includes a membrane electrode assembly 2 having a frame 1 around it, and anode-side and cathode-side separators 3 and 4 sandwiching the frame 1 and the membrane electrode assembly 2. . Since the fuel cell FC used for the on-vehicle power source of the electric vehicle requires a large number of single cells C, it is very important to make the single cells C thinner. In the single cell C of the present invention, a plastic film 1A is used for the frame 1 as one configuration for reducing the thickness.

  As shown in FIG. 3, the frame 1 is formed by bonding a plurality of (in the illustrated example, two) plastic films 1 </ b> A and 1 </ b> A, and is bonded while sandwiching the peripheral edge of the membrane electrode assembly 2. Thus, it is integrated with the membrane electrode assembly 2. Examples of the material of the plastic film 1A include polyethylene naphthalate (PEN), polypropylene (PP), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and polyvinylidene fluoride (PVDF).

  In this embodiment, the frame 1 has a rectangular shape with the membrane electrode assembly 2 in the center. The frame 1 has three manifold holes H1 to H6 arranged at both ends on the short side, and the region from each manifold hole group to the membrane electrode assembly 2 performs gas rectification and the like. This is the diffuser region D for this purpose. That is, the single cell C has a diffuser region D for flowing a reaction gas to the membrane electrode assembly 2 between the frame 1 and the separators 3 and 4.

  The membrane electrode assembly 2 is generally called MEA (Membrane Electrode Assembly), and has a structure in which an electrolyte layer made of, for example, a solid polymer is sandwiched between a fuel electrode layer (anode) and an air electrode layer (cathode). Have. This membrane electrode assembly 2 is supplied with anode gas (hydrogen) to the fuel electrode layer and supplied with cathode gas (hydrogen) to the air electrode layer, and generates power by an electrochemical reaction.

  Each of the separators 3 and 4 is a metal plate member having an inverted shape, and is made of stainless steel, for example, and can be formed into an appropriate shape by pressing. Each of the separators 3 and 4 has a central portion corresponding to the membrane electrode assembly 2 formed in a wave shape in a cross section in the short side direction. This wave shape is continuous in the long side direction as shown in the figure. Thereby, each separator 3 and 4 has each convex part in contact with the membrane electrode assembly 2 in the central part corresponding to the membrane electrode assembly 2 in the wave shape, and each concave part in the wave shape is the gas flow path. Become. Each separator 3A, 3B has manifold holes H1 to H6 equivalent to the manifold holes H1 to H6 of the frame 1 at both ends.

  In the frame 1 and the separators 3 and 4, the manifold holes H1 to H3 shown on the left side of FIG. 2 are for anode gas supply (H1), cooling fluid discharge (H2), and cathode gas discharge (H3), Each flow path is formed in communication with each other in the stacking direction. Also, the manifold holes H4 to H6 shown on the right side of FIG. 2 are for cathode gas supply (H4), cooling fluid supply (H5), and anode gas discharge (H6), and communicate with each other in the stacking direction. The flow path is formed. The supply and discharge may be partially or entirely reversed in positional relationship.

  Further, a sealing material S is disposed around the peripheral edge of the frame 1 and the separators 3 and 4 and around the manifold holes H1 to H6. These sealing materials also function as adhesives, and airtightly join the frame 1 and membrane electrode assembly 2 to the separators 3 and 4. Further, the sealing material S arranged around the manifold holes H1 to H6 has an opening at a corresponding portion in order to supply fluid according to each layer while maintaining the airtightness of each manifold.

  The unit cell C is formed by stacking a predetermined number of cell modules M. At this time, a flow path of the cooling liquid (for example, water) is formed between the adjacent single cells C, and a flow path of the cooling liquid is also formed between the adjacent cell modules M. Therefore, the seal plate P is disposed between the cell modules M, that is, in the flow path of the coolant.

  The seal plate P is formed by molding a single conductive metal plate, is formed in the same rectangular plate shape and in the same size as the above-described single cell C in plan view, and on both short sides, Manifold holes H1 to H6 similar to the single cell C are formed. This seal plate P is provided with a seal member (not shown) around each of the manifold holes H1 to H6, and an outer peripheral seal member 51 and an inner peripheral seal member 52 are provided in parallel on the entire periphery thereof, The outer peripheral seal member 51 prevents rainwater and the like from entering from the outside, and the inner peripheral seal member 52 prevents leakage of the coolant flowing through the flow path between the cell modules M.

  Here, the unit cell C constituting the fuel cell FC includes a membrane electrode assembly 2 having a frame 1 formed by bonding a plurality of plastic films 1A around, a magnetic body 5 disposed on the frame 1, Anode-side and cathode-side separators 3 and 4 sandwiching the frame 1 and the membrane electrode assembly 2 are provided. In short, the magnetic body 5 may be any member that can be attracted by a magnet, and a ferromagnetic body or a paramagnetic body can be used. Specifically, a metal plate such as a steel plate or a metal fiber is used. Can do.

  Further, in the single cell C, as a more preferable embodiment, the magnetic body 5 is disposed between the plastic films 1A constituting the frame 1. Further, as a more preferred embodiment, the single cell C has a diffuser region D for flowing a reaction gas to the membrane electrode assembly 2 between the frame 1 and the separators 3 and 4, and a magnetic material. 5 is arranged in the diffuser region D.

  Furthermore, the single cell C has a sealing member S between the frame 1 and the separators 3 and 4 as a more preferable embodiment, and the magnetic body 5 is disposed at a position corresponding to the sealing member S. Further, the magnetic body 5 is embedded in an adhesive 31 applied to the plastic film 1A.

  The single cell C having the above structure is manufactured by the manufacturing method described below. That is, in the manufacturing method of the single cell C, as a first step, the magnetic body 5 is disposed between the plastic films 1A and 1A, and the frame 1 and the membrane electrode assembly 2 made of the plastic films 1A and 1A are combined. Integrate.

  Thereafter, the manufacturing method of the single cell C is such that the adhesive is applied to the peripheral portion of the separator 3 (4) on either the anode side or the cathode side, and then the membrane electrode bonding having the frame 1 on the separator 3 (4). The body 2 is laminated (step A), and an adhesive is applied to the peripheral portion of the frame 1, and then the other separator 4 (3) is laminated on the frame 1 and the membrane electrode assembly 2 (step B). Then, after at least one of the process A and the process B, a magnetic field is applied to the magnetic body 5 in the thickness direction of the frame 1.

  As described above, the unit cell C manufactured by the above-described unit cell manufacturing method includes a membrane electrode assembly 2 having a frame 1 formed by bonding a plurality of plastic films 1A and 1A, a frame 1 and a membrane. Anode-side and cathode-side separators 3 and 4 sandwiching the electrode assembly 2 are provided. And the single cell C has the structure which has arrange | positioned the magnetic body 5 between the plastic films 1A and 1A which form the flame | frame 1, as shown to FIG. 3 (A) and (B). Further, anode-side and cathode-side gas diffusion layers 6 and 7 made of a porous material are provided on both surfaces of the illustrated membrane electrode assembly 2.

  The method for manufacturing the single cell C will be described more specifically. The plastic film 1A forming the frame 1 is formed in a roll shape as shown on the left side of FIG. 3C, and is arranged vertically in the production line. In addition, an opening (not shown) for exposing the membrane electrode assembly 2 is formed in the plastic film 1A in advance.

  The magnetic body 5 in the illustrated example is a member having a frame shape surrounding the membrane electrode assembly 2 as indicated by a dotted line in FIG. The magnetic body 5 is not particularly limited as long as it is a member that can be attracted by a magnet, and is, for example, a SUS400 steel plate. As shown in FIG. 3B, the thickness of the magnetic body 5 can be determined from the step size h between the frame 1 and the gas diffusion layer 6 (7).

  And the manufacturing method of the single cell C arrange | positions the membrane electrode assembly 2 and the magnetic body 5 between the upper and lower plastic films 1A and 1A, and then, as shown on the right side of FIG. The plastic film 1 </ b> A, 1 </ b> A is bonded with adhesives 31, 31 to form the frame 1. Thereby, the frame 1 is integrated with the membrane electrode assembly 2 in a state where the peripheral portion of the membrane electrode assembly 2 and the magnetic body 5 are sandwiched.

  In order to integrate the frame 1 and the membrane electrode assembly 2 as described above, several methods shown in FIG. 4 can be selected. In the method shown in FIG. 4A, the membrane electrode assembly 2 and the magnetic body 5 are arranged on one plastic film 1A to which the adhesive 31 has been applied in advance, and the adhesive 31 is applied on the upper side of the membrane electrode assembly 2A. A plastic film 1A is laminated, and the frame 1 and the membrane electrode assembly 2 are integrated as shown in FIG. Thereafter, as shown in FIG. 4C, gas diffusion layers 6 and 7 are laminated on a part of the frame 1 and the whole membrane electrode assembly 2.

  In the method shown in FIG. 4D, the membrane electrode assembly 2 and the magnetic body 5 are sandwiched between one plastic film 1A preliminarily coated with the adhesive 31 and the other plastic film 1A similarly coated with the adhesive 31. Then, the frame 1 and the membrane electrode assembly 2 are integrated as shown in FIG.

  In the method shown in FIG. 4E, the membrane electrode assembly 2 and the magnetic body 5 are arranged on one plastic film 1A to which the adhesive 31 is applied in advance, and the other plastic film 1A is laminated on the upper side, The peripheral edge of the membrane electrode assembly 2 and the magnetic body 5 are embedded in the adhesive 31, and the frame 1 and the membrane electrode assembly 2 are integrated as shown in FIG.

  The frame 1 and the membrane electrode assembly 2 integrated as described above are laminated with the separators 3 and 4 to form a single cell C through the steps shown in FIGS. In the following steps, the anode-side separator 3 is laminated in the lower stage and the cathode-side separator 4 is laminated in the upper stage, but of course, the anode side and the cathode side may be turned upside down.

  That is, as shown in FIGS. 5A and 6, the adhesive 31 is applied to the lower separator 3 in step S <b> 1, and the lower separator 3 is placed on the lower jig 41 in step S <b> 2. At this time, a spacer 43 corresponding to the thickness of the single cell C is disposed on the lower jig 41 at an appropriate location.

  Next, as shown in FIGS. 5B and 6, an adhesive 31 is applied to the frame 1 in step S3, and the frame 1 and the membrane electrode assembly (MEA) 2 are placed on the lower separator 3 in step S4. Are laminated. Next, as shown in FIGS. 5C and 6, the upper separator 4 on the frame 1 and the membrane electrode assembly 2 is stacked in step S5, and the upper jig 42 is installed in step S6.

  Thereafter, by generating a magnetic field in step S7 of FIG. 6, a magnetic field is applied to the magnetic body 5 in the thickness direction of the frame 1 as indicated by an arrow B in FIG. , 42 are fixed to each other. Thereby, the magnetic body 5 is held at the center in the thickness direction of the single cell C. In this state, the adhesive 31 is cured in step S9. After the adhesive 31 is cured, the upper and lower jigs 41 and 42 are released in step S10, and the single cell C is taken out in step S11.

  According to the manufacturing method of the single cell C described above, a magnetic field is applied to the magnetic body 5 when manufacturing the single cell C including the membrane electrode assembly 2 having the frame 1 made of the plastic films 1A and 1A around it. Thus, the frame 1 and the separators 3 and 4 are bonded while the magnetic body 5 is held in the center in the thickness direction of the single cell C, so that the deformation of the frame 1 can be prevented.

  By the way, in the manufacturing method not using the magnetic body 5, the upper and lower jigs are used to dispose the frame and the membrane electrode assembly between the anode-side and cathode-side separators and bond each with an adhesive. Therefore, the position of the frame is not stable in the thickness direction, and in particular, the frame is often lowered by gravity. For this reason, the frame is deformed and the thicknesses of the adhesive layers on both sides of the frame are also different.

  On the other hand, the single cell C manufactured by the single cell structure and the single cell manufacturing method of the present invention has the frame 1 enhanced in rigidity by the magnetic body 5 and has a good frame 1 without deformation. The thickness of the adhesive layer (31) on both sides of the frame 1 is also uniform, and the sealing performance by the adhesive layer (31) is also improved.

Second Embodiment
FIG. 7 is a flowchart for explaining a second embodiment of the method for producing a single cell according to the present invention. In this embodiment, steps S21 to S24 and steps S28 to S31 are the same as steps S1 to S4 and steps 8 to 11 of the first embodiment.

  That is, in the first embodiment (see FIG. 6), the lower separator 3, the frame 1 and the membrane electrode assembly 2, and the upper separator 4 are stacked to generate a magnetic field. In the embodiment, in steps S21 to S24, after laminating the frame 1 and the membrane electrode assembly 2 on the lower separator 3, a magnetic field is generated in step S25, and as shown by an arrow B in FIG. Is applied with a magnetic field in the thickness direction of the frame 1. Thereafter, the upper separator 4 is laminated on the frame 1 and the membrane electrode assembly 2 in step S26.

  Also by the manufacturing method of the single cell C, the frame 1 and the separators 3 and 4 are bonded while the magnetic body 5 is held in the center in the thickness direction of the single cell C, so that deformation of the frame 1 is prevented. be able to. And the single cell C manufactured by this manufacturing method has the rigidity of the frame 1 enhanced by the magnetic body 5 and is provided with the good frame 1 without deformation. The adhesive layers (31) on both sides of the frame 1 are provided. The thickness becomes uniform, and the sealing performance by the adhesive layer (31) is improved.

<Third Embodiment>
FIG. 8A and FIG. 9 are diagrams for explaining an embodiment of a fuel cell stack according to the present invention and a fuel cell stack manufactured by the method. Note that the same components as those in the previous embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  The manufacturing method of the fuel cell stack in this embodiment exemplifies the case of manufacturing the cell module M that constitutes the fuel cell FC shown in FIG. 1, and includes the frame 1 described in the first embodiment and the manufacturing method. The membrane electrode assembly 2 is used, that is, the membrane electrode assembly 2 having the frame 1 in which the magnetic body 5 is disposed between the plastic films 1A and 1A.

  As shown in FIG. 5 of the first embodiment, the fuel cell stack is manufactured by applying an adhesive 31 to the peripheral edge of the separator 3 on either the anode side or the cathode side and then applying the frame 1 to the separator 3. The membrane electrode assembly 2 having the above structure is laminated (step A), the adhesive 31 is applied to the peripheral edge of the frame 1, and then the other separator 4 is laminated on the frame 1 and the membrane electrode assembly 2 (step B). Then, the process A and the process B are repeated a predetermined number of times, and a magnetic field is applied to the magnetic body 5 in the thickness direction of the frame 1 after at least one of the processes A and B.

  As shown in FIG. 8A, the fuel cell stack (cell module M) manufactured by the above manufacturing method has a membrane electrode assembly having a frame 1 formed by bonding a plurality of plastic films 1A and 1A around it. 2 and a single cell C provided with anode-side and cathode-side separators 3, 4 that sandwich the frame 1 and the membrane electrode assembly 2. And the magnetic body 5 is arrange | positioned between the plastic films 1A and 1A which form the flame | frame 1 in each single cell C. FIG.

  Based on FIG. 8 and FIG. 9, the manufacturing method of the cell module M as a fuel cell stack is demonstrated more concretely. That is, the adhesive 31 is applied to the lower separator 3 in step S41 of FIG. 9, and the lower separator 3 is placed on the lower jig 41 in step S42. A spacer 44 corresponding to the thickness of the cell module M is disposed on the lower jig 41 at an appropriate location.

  Next, the adhesive 31 is applied to the frame 1 in step S43, and the frame 1 and the membrane electrode assembly (MEA) 2 are laminated on the lower separator 3 in step S44. Thereafter, a magnetic field is generated in step S45, and a magnetic field in the thickness direction of the frame 1 is applied to the magnetic body 5 as indicated by an arrow B in FIG. Holding in the center of the direction prevents deformation of the frame 1.

  Furthermore, the adhesive 31 is applied to the upper separator 4 in step S46, and the upper separator 4 is laminated on the frame 1 and the membrane electrode assembly 2 in step S47. Thereafter, in step S48, it is determined whether or not a predetermined number of single cells are stacked. If it is determined that the predetermined number is not reached (NO), steps S41 to S47 are repeated. At this time, from the second round, as indicated in parentheses in step S42, the lower separator 3 of the single cell C adjacent to the upper side is stacked on the upper separator 4.

  If it is determined in step S48 that the predetermined number has been reached (YES), the upper jig 42 is installed in step S49, and the upper and lower jigs 41, 42 are fixed in step S50. Thereafter, the adhesive 31 is cured in step S51, and after the adhesive 31 is cured, the upper and lower jigs 41 and 42 are fixed in step S52, and the cell module (fuel cell stack) M is taken out in step S53.

  According to the manufacturing method of the fuel cell stack described above, when manufacturing the cell module M formed by stacking the single cells C, a magnetic field is applied to the magnetic body 5 so that the thickness of each single cell C is reduced. Since the frame 1 and the separators 3 and 4 are bonded while being held in the center in the direction, deformation of the frame 1 in each single cell can be prevented.

  The cell module (fuel cell stack) M manufactured by the fuel cell stack manufacturing method described above has a frame 1 in which the rigidity of the frame 1 is increased by the magnetic body 5 in each single cell C, and a good frame 1 without deformation is formed. The thickness of the adhesive layer (31) on both sides of the frame 1 of each unit cell C is uniform, and the sealing performance by the adhesive layer (31) is improved. That is, it is possible to obtain a high-quality cell module M in which the accuracy variation of each single cell C is extremely small.

<Fourth embodiment>
FIG. 8B and FIG. 10 are views for explaining a fuel cell stack manufacturing method of the present invention and a fuel cell stack manufactured by the manufacturing method according to a fourth embodiment. Note that the same components as those in the third embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The manufacturing method of the fuel cell stack in this embodiment is a method of manufacturing the cell module M as in the third embodiment. In the manufacturing method of this embodiment, the adhesive 31 is applied to the peripheral edge of the separator 3 on either the anode side or the cathode side, and then the membrane electrode assembly 2 having the frame 1 is laminated on the separator 3 (process) A) After applying the adhesive 31 to the peripheral edge of the frame 1, the other separator 4 is laminated on the frame 1 and the membrane electrode assembly 2 (step B).

  In the manufacturing method of this embodiment, Step A and Step B are repeated a predetermined number of times, and a magnetic field is applied to the magnetic body 5 in the thickness direction of the frame 1 after at least one of Step A and Step B. . Further, in the manufacturing method of this embodiment, the separator 3 on one side of the single cell C to be stacked next is integrated with the separator 4 on the other side in the step B in advance.

  That is, in the manufacturing method of this embodiment, the frame 1 and the membrane electrode assembly 2 described in the first embodiment and the bonding separator 34 shown in FIG. 8B are used. The joining separator 34 is obtained by previously integrating the upper separator 4 of the single cell C and the lower separator 3 of the single cell C adjacent to the upper side thereof, and is joined and fixed differently by means such as welding.

  In the fuel cell stack manufacturing method, the adhesive 31 is applied to the lower separator 3 in step S61 of FIG. 10, and the lower separator 3 is placed on the lower jig 41 in step S62. Next, the adhesive 31 is applied to the frame 1 in step S63, and the frame 1 and the membrane electrode assembly (MEA) 2 are laminated on the lower separator 3 in step S64. Thereafter, a magnetic field is generated in step S65, and a magnetic field in the thickness direction of the frame 1 is applied to the magnetic body 5 as indicated by an arrow B in FIG. Thereby, the magnetic body 5 is held at the center in the thickness direction of the single cell C, and deformation of the frame 1 is prevented.

  Furthermore, in this embodiment, the adhesive 31 is applied to the weld separator 34 in step S66, and the weld separator 34 is laminated on the frame 1 and the membrane electrode assembly 2 in step S67. Next, in step S68, it is determined whether or not the predetermined number-1 single cells C are stacked. If it is determined that the predetermined number-1 is not satisfied (NO), steps S63 to S67 are repeated. At this time, from the second round, as indicated in parentheses in step S64, the frame 1 and the membrane electrode assembly 2 are stacked on the bonding separator 34.

  That is, in this embodiment, since the joining separator 34 in which the two separators 3 and 4 are joined and fixed to each other is used, the upper unit single cell C is laminated with a single upper separator 4 instead of the joining separator 34. To do. Therefore, in step S68, it is determined whether or not the number of single cells C is a predetermined number minus one.

  Therefore, if it is determined in step S68 that the predetermined number has reached -1 (YES), the adhesive 31 is applied to the last frame (the uppermost frame at that time) 1 in step S69, and in step S70. The frame 1 and the membrane electrode assembly 2 are laminated on the weld separator 34. Thereafter, a magnetic field is generated again in step S71 to apply the magnetic field to the magnetic body 5 in the uppermost frame 1. Thereby, in the uppermost unit cell C, the magnetic body 5 is held at the center in the thickness direction, and deformation of the frame 1 is prevented.

  Further, the adhesive 31 is applied to the upper separator (uppermost separator) 4 in step S72, and the upper separator 4 is laminated on the frame 1 and the membrane electrode assembly 2 in step S73. Next, the upper jig 42 is installed in step S74, and the upper and lower jigs 41 and 42 are fixed in step S75. Thereafter, the adhesive 31 is cured in step S76, and after the adhesive 31 is cured, the upper and lower jigs 41 and 42 are fixed in step S77, and the cell module (fuel cell stack) M is taken out in step S78.

  According to the fuel cell stack manufacturing method described above, when the cell module M formed by stacking the single cells C is manufactured, the frame 1 and the separator are held while the magnetic body 5 is held at the center in the thickness direction of each single cell C. Since adhesion with 3 and 4 is performed, deformation of each single cell frame 1 can be prevented. In addition, since the separators 3 and 4 of the intermediate layer are integrated in advance to form the joining separator 34, the stacking operation can be speeded up.

  The cell module (fuel cell stack) M manufactured by the fuel cell stack manufacturing method described above includes a good frame 1 in which the rigidity of the frame 1 is increased by the magnetic body 5 in each single cell C, and there is no deformation. Thus, the thickness of the adhesive layer (31) on both sides of the frame 1 of each unit cell C is also uniform, and the sealing performance by the adhesive layer (31) is improved. That is, it is possible to obtain a high-quality cell module M in which the accuracy variation of each single cell C is extremely small. Further, since the joining separator 34 is integrated by welding and fixing the two separators 3 and 4 to each other by welding or the like, a strong joining state is obtained, and the electrical contact resistance between the separators 3 and 4 is reduced. Can do.

<Fifth Embodiment>
FIG. 11 is a diagram for explaining another embodiment of a magnetic body used in the method for producing a single cell and the method for producing a fuel cell stack according to the present invention. Note that the same components as those described in the previous embodiment are denoted by the same reference numerals and description thereof is omitted.

  That is, the magnetic body 5 shown in FIG. 11A is a member obtained by molding a metal material into a plate having a certain thickness, as exemplified in the previous embodiments. A magnetic body 15 shown in FIG. 11B is a member obtained by forming a metal porous body into a plate having a certain thickness. A magnetic body 25 shown in FIG. 11C is a member obtained by forming metal fibers into a woven fabric shape, a nonwoven fabric shape, or a mixture thereof into a plate shape having a constant thickness. The magnetic body 35 shown in FIG. 11D is a plate-like member that has protrusions 35A on the front and back surfaces and is partially thickened by the protrusions 35A.

  Thus, although the magnetic bodies are all made of metal, for example, as shown in FIG. 11 according to the characteristics and dimensional relationship with each constituent member of the single cell C, the strength of the magnetic field applied at the time of manufacture, and the like. In addition, the form of the material and the form of the member can be appropriately selected.

<Sixth Embodiment>
A single cell C shown in FIG. 12 has a diffuser region D for flowing a reaction gas to the membrane electrode assembly 2 between the frame 1 and the separators 3 and 4. This diffuser region D is the same as that described in the first embodiment (see FIG. 3), the region extending from one manifold hole H1 to H3 to the membrane electrode assembly 2, and the other manifold hole H4 to H5. To the membrane electrode assembly 2.

  Further, the single cell C has a seal member S between the frame 1 and the separators 3 and 4. The seal member S seals between the gas flow paths on the anode side and the cathode side and the outside, similar to the one shown in FIG. 2 of the first embodiment.

  In the single cell C, as shown in the dotted line in FIG. 12A and FIG. 12B, the magnetic body 45 is disposed at a position corresponding to the diffuser region D in the frame 1. The magnetic body 45 is a rectangular plate-like member made of any of the material forms illustrated in FIG. 11, for example. Further, in the single cell C, as shown in the dotted line in FIG. 12A and FIG. 12C, the magnetic body 5 is disposed at a position corresponding to the seal portion S in the frame 1. The magnetic body 5 is a frame-like member that surrounds the membrane electrode assembly 2 in the same manner as that shown in FIG. 3 of the first embodiment.

  Even in the single cell C described above, the magnetic bodies 4 and 45 are manufactured by applying a magnetic field by the manufacturing method described in the first and second embodiments (FIGS. 5 to 7). In this single cell C, since the magnetic body 45 is disposed at a position corresponding to the diffuser region D in the frame 1, the deformation of the frame 1 is prevented and the magnetic body 45 also functions as a reinforcing member.

  In this type of single cell C, a seal member S is interposed between the peripheral edges of the frame 1 and the separators 3 and 4, and the membrane electrode assembly 2 and the separators 3 and 4 are separated from each other by the separators 3 and 4. Because of the contact at the corrugated convex portions, the positional relationship between these members is stable. However, the diffuser region D requires a certain area, and since there are no inclusions between the frame 1 and the separators 3 and 4, the frame 1 is easily bent. For this reason, during the operation of the fuel cell, the single cell C bends in the frame 1 due to the pressure difference between the gas on the anode side and the cathode side, and when this bending is repeatedly received, the frame 1 and the membrane electrode assembly 2 There is a possibility that stress concentrates on the joint portion of different kinds of materials, such as, and breaks.

  On the other hand, in the single cell C of this embodiment, since the magnetic body 45 is disposed in a portion corresponding to the diffuser region D in the frame 1, the rigidity of the frame 1 is increased, and the magnetic body 45 is attached to the frame 1. As a reinforcing member, it is possible to suppress the bending of the frame 1 during operation, thereby preventing the frame 1 and the membrane electrode assembly 2 from being damaged.

  Furthermore, since the magnetic body 5 is arrange | positioned in the position corresponding to the sealing member S in the flame | frame 1 in said single cell C, the favorable sealing performance by the sealing member S can be maintained over a long period of time. That is, the single cell C is manufactured while applying a magnetic field to the magnetic body 5 to maintain the frame 1 at the center in the thickness direction of the single cell C and to include the frame 1 without deformation. As a result, on both sides of the frame 1, the distance between the seal layers by the seal member S and the pressure contact force against both the seal members S are equalized, and good sealing performance by the seal member S is ensured.

<Seventh embodiment>
In a cell module (fuel cell stack) M shown in FIG. 13, a predetermined number of single cells C described in the sixth embodiment are stacked, and the seal plate P described in the first embodiment is disposed at the end in the stacking direction. It is a thing. The cell module M is manufactured by the manufacturing method described in the fourth and fifth embodiments (FIGS. 8 to 10). At this time, in the cell module M, the magnetic bodies 5 and 45 are arranged at positions corresponding to at least one of the outer peripheral seal member 51 and the inner peripheral seal member 52 of the seal plate P.

  Even in the cell module M described above, the deformation of the frame 1 in each single cell C is prevented, and the magnetic body 45 disposed in each frame 1 also functions as a reinforcing member. As a result, the cell module M has a high quality with very little variation in accuracy of each single cell C, and the frame 1 and the membrane electrode joint are suppressed by suppressing the bending of the frame 1 of each single cell C during operation. This prevents the body 2 from being damaged.

  Further, the cell module M can maintain a good sealing performance by the seal member S in each single cell C over a long period of time, and by laminating such single cells C, the outer peripheral seal member 51 of the seal plate P and Similarly, good sealing performance can be maintained for the inner peripheral seal member 52 over a long period of time.

  The configuration of the single cell manufacturing method according to the present invention, the single cell manufactured by the manufacturing method, and the fuel cell stack manufacturing method and the fuel cell stack manufactured by the manufacturing method are limited to the above embodiments only. However, it is possible to combine the configurations of the embodiments and to change the material, shape, size, number, and the like of each member without departing from the gist of the present invention. In the above embodiment, the cell module is exemplified as the fuel cell stack. However, the fuel cell stack may be formed by stacking a plurality of single cells, and may be other than the cell module.

C Single cell D Diffuser area FC Fuel cell M Cell module (fuel cell stack)
S Seal member 1 Frame 1A Plastic film 2 Membrane electrode assembly 3 Anode side separator 4 Cathode side separator 5, 15, 25, 35, 45 Magnetic body 31 Adhesive

Claims (16)

A membrane electrode assembly having a frame formed by bonding a plurality of plastic films around,
A magnetic body arranged in a frame;
An anode-side and cathode-side separator that sandwiches the frame and membrane electrode assembly;
A single cell structure characterized by comprising:   2. The single cell structure according to claim 1, wherein the magnetic body is disposed between the plastic films constituting the frame. Between the frame and the separator, has a diffuser region for flowing the reaction gas to the membrane electrode assembly,
3. The single cell structure according to claim 1, wherein the magnetic body is disposed in the diffuser region. Having a seal member between the frame and the separator;
The single cell structure according to any one of claims 1 to 3, wherein the magnetic body is arranged at a position corresponding to the seal member.   The single cell structure according to any one of claims 1 to 4, wherein the magnetic material is embedded in an adhesive applied to a plastic film. When manufacturing a single cell comprising a membrane electrode assembly having a frame formed by laminating a plurality of plastic films, and an anode side and cathode side separator sandwiching the frame and the membrane electrode assembly,
A magnetic body is arranged between plastic films, and the frame made of the plastic film and the membrane electrode assembly are integrated.
(A) After applying an adhesive to the peripheral edge of the separator on either the anode side or the cathode side, laminating a membrane electrode assembly having a frame on the separator,
(B) After applying an adhesive to the peripheral edge of the frame, the other separator is laminated on the frame and membrane electrode assembly,
A method of manufacturing a single cell, comprising applying a magnetic field in the thickness direction of a frame to a magnetic material after at least one of the steps (A) and (B). The single cell has a diffuser region for flowing a reaction gas to the membrane electrode assembly between the frame and the separator,
6. The method of manufacturing a single cell according to claim 5, wherein a magnetic material is disposed at a position corresponding to the diffuser region in the frame. The single cell has a seal member between the frame and the separator,
The method of manufacturing a single cell according to claim 6 or 7, wherein a magnetic body is disposed at a position corresponding to the seal member in the frame.   The method of manufacturing a single cell according to any one of claims 6 to 8, wherein the magnetic body is a member obtained by forming a metal material into a plate shape. A fuel cell formed by laminating a single cell including a membrane electrode assembly having a frame formed by laminating a plurality of plastic films, and an anode side and cathode side separator sandwiching the frame and the membrane electrode assembly. When manufacturing the stack,
Using a membrane electrode assembly having a frame around which a magnetic material is placed between plastic films,
(A) After applying an adhesive to the peripheral edge of the separator on either the anode side or the cathode side, laminating a membrane electrode assembly having a frame on the separator,
(B) After applying an adhesive to the peripheral edge of the frame, the other separator is laminated on the frame and membrane electrode assembly,
A fuel characterized by repeating steps (A) and (B) a predetermined number of times and applying a magnetic field in the thickness direction of the frame to the magnetic material after at least one of steps (A) and (B). Battery stack manufacturing method.   11. The method for manufacturing a fuel cell stack according to claim 10, wherein a separator on one side of a single cell to be stacked next is integrated in advance with the separator on the other side in the step (B). The single cell has a diffuser region for flowing a reaction gas to the membrane electrode assembly between the frame and the separator,
The method for manufacturing a fuel cell stack according to claim 10 or 11, wherein a magnetic body is disposed at a position corresponding to the diffuser region in the frame. The single cell has a seal member between the frame and the separator,
The method of manufacturing a fuel cell stack according to any one of claims 10 to 12, wherein a magnetic body is disposed at a position corresponding to the seal member in the frame.   The method of manufacturing a fuel cell stack according to any one of claims 10 to 13, wherein the magnetic body is a member obtained by forming a metal material into a plate shape. A single cell manufactured by the method for manufacturing a single cell according to any one of claims 6 to 9,
A membrane electrode assembly having a frame formed by laminating a plurality of plastic films, and an anode-side and cathode-side separator sandwiching the frame and the membrane-electrode assembly; A single cell characterized in that a magnetic material is disposed between them. A fuel cell stack manufactured by the method for manufacturing a fuel cell stack according to any one of claims 10 to 14,
A single cell comprising a membrane electrode assembly having a frame formed by laminating a plurality of plastic films and a separator on the anode side and cathode side sandwiching the frame and the membrane electrode assembly is laminated. A fuel cell stack, wherein a magnetic material is disposed between plastic films forming a frame in a single cell.

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