JP6148956B2 - Manufacturing method of laminate - Google Patents

Description

  The present invention relates to a method for manufacturing a laminate in which elastic members are arranged on both sides in the thickness direction of a thin plate, which is used as a component of a fuel cell.

  In a fuel cell, a cell in which an electrode member including a membrane electrode assembly (MEA) is sandwiched by a separator is a power generation unit. A fuel cell is configured by stacking a number of cells. A frame-shaped sealing member is disposed around the electrode member and between adjacent separators in order to ensure sealing and insulating properties against gas and refrigerant.

  As a method for producing a fuel cell assembly including a seal member, for example, in Patent Documents 1 to 3, a preformed body made of an uncrosslinked elastomer is disposed on both sides (upper surface and lower surface) of the separator in the thickness direction. A method is disclosed in which the preform is cross-linked and integrated while sandwiching these with a mold.

JP 2012-243580 A JP 2004-178777 A JP 2005-47262 A

  However, in the methods described in Patent Documents 1 to 3, there is a problem that the separator sandwiched between the preforms is bent upward or downward due to the thermal expansion of the preform during crosslinking. there were. The direction and amount of bending of the separator vary depending on conditions such as the type of elastomer, the size of the preform, and the mold structure. For this reason, it is difficult to control the bending direction and the bending amount of the separator.

  As an example, FIG. 12 shows an enlarged cross-sectional view of the vicinity of the peripheral edge of a fuel cell assembly manufactured by a conventional method. As shown in FIG. 12, the cell assembly 9 includes a first separator 90, a second separator 91, a first seal member 92, and a second seal member 93. The first seal member 92 is disposed on the upper surface of the first separator 90. The second seal member 93 is disposed on the lower surface of the first separator 90. The second seal member 93 is disposed between the first separator 90 and the second separator 91. In the first separator 90, a portion 900 sandwiched between the first seal member 92 and the second seal member 93 is curved downward (second seal member 93 side).

  In this case, the distance between the first separator 90 and the second separator 91 is reduced by the amount of the first separator 90 being curved. Thereby, in the vicinity of the bending region of the first separator 90, the first separator 90 and the second separator 91 may come into contact with each other and short-circuit. When a fuel cell is configured by stacking a large number of cell assemblies 9, the first seal member 92 includes a first separator 90 and another cell assembly to be stacked (in FIG. 12, a thin line above the cell assembly 9. Between the second separator and the second separator. When the first separator 90 is curved downward, the interval between the separators adjacent via the first seal member 92 is increased. As a result, the reaction force of the first seal member 92 is reduced and the sealing performance is deteriorated.

  On the other hand, when the 1st separator 90 curves to the upper side (1st seal member 92 side), in a fuel cell, the space | interval of the separators which adjoin via the 1st seal member 92 becomes small. Thereby, the 1st seal member 92 will be in an overcompressed state, and will be easy to be damaged.

  The present invention has been made in view of such a situation, and provides a method for manufacturing a laminate that can form an elastic member made of elastomer on both sides in the thickness direction of a thin plate without deforming the thin plate. This is the issue.

  From the viewpoint of suppressing the deformation of the separator at the time of cross-linking, the present inventor did not form two seal members arranged with the separator sandwiched at the same time, but formed one by cross-linking first. Later, a method of cross-linking the other was studied. That is, first, a first seal member made of elastomer is formed on the upper surface of the separator. Next, an uncrosslinked elastomer is placed on the lower surface of the separator, and the uncrosslinked product is crosslinked to form a second seal member.

  However, this method has the following problems. The metal mold | die arrange | positioned at the upper surface side of a separator has a 1st recessed part for accommodating the 1st sealing member formed beforehand. The shape and size of the first recess are the same as the shape and size of the first seal member. In this case, if a slight misalignment occurs when setting the mold, the opening end of the first recess and the first seal member come into contact with each other, and the first seal member is damaged. On the other hand, if the first concave portion of the mold is designed larger than the first seal member in consideration of positional deviation, the first seal member cannot be sufficiently pressed by the mold even if the mold is clamped. As a result, at the time of crosslinking, the pressing force from the lower surface side due to the expansion of the uncrosslinked product cannot be resisted, and the separator is curved upward (first seal member side). In order to solve these problems, the present inventor has intensively studied and completed the method for producing the laminate of the present invention.

  (1) The manufacturing method of the laminated body of this invention is a manufacturing method of the laminated body which has a thin plate and the 1st elastic member and 2nd elastic member made from an elastomer arrange | positioned at the thickness direction both surfaces of this thin plate. The direction in which the first elastic member, the thin plate, and the second elastic member are laminated is a lamination direction, and a direction orthogonal to the lamination direction is a plane direction, and both sides of the thin plate in the lamination direction A first elastic member disposing step of disposing the first elastic member on the first surface of the thin plate, using one of the first surface, the other as the second surface, and an uncrosslinked product of the elastomer as an elastomer material; A mold clamping step in which the thin plate in which the first elastic member is disposed on the first surface is disposed in the mold, and the elastomer material is disposed on the second surface side of the thin plate to perform the mold clamping. By heating the mold after clamping, the elastomer material is cross-linked and the second A second elastic member forming step for forming a second elastic member on the surface, and the mold has a first recess for receiving the first elastic member, and in the clamping step, The elastic member is characterized in that it is stretched in the surface direction while being compressed in the laminating direction and is accommodated in the first recess.

  The metal mold | die used in a mold clamping process and a 2nd elastic member formation process has a 1st recessed part for accommodating a 1st elastic member. The shape and size of the first recess are not the same as the shape and size of the first elastic member disposed on the first surface of the thin plate. For this reason, in the mold clamping step, the first elastic member extends in the surface direction while being compressed in the stacking direction and is accommodated in the first recess. By compressing the first elastic member in the stacking direction, the thin plate is pressed by the first elastic member. Thereby, the pressing force from the second surface side due to the expansion of the elastomer material at the time of crosslinking can be resisted. Therefore, the curve to the 1st elastic member side of the thin plate in a 2nd elastic member formation process can be suppressed.

  Thus, according to the method for manufacturing a laminate of the present invention, a laminate in which the first elastic member and the second elastic member made of elastomer are formed on both surfaces in the thickness direction of the thin plate without deforming the thin plate is manufactured. can do.

  (2) Preferably, in the configuration of (1), the opening width in the surface direction of the first recess is larger than the width in the surface direction of the first elastic member before the mold clamping step. Good.

  In this configuration, when the cross-section in the stacking direction of the first recess is compared with the corresponding cross-section in the stacking direction of the first elastic member, the opening width of the first recess is larger than the maximum length of the first elastic member. It only needs to be large. According to this configuration, even if a positional shift occurs when the mold is set in the mold clamping process, the opening end of the first recess and the first elastic member are unlikely to contact each other. Therefore, damage to the first elastic member during mold clamping can be avoided.

  (3) Preferably, in the configuration of the above (1) or (2), the laminate may be a component of a fuel cell.

  As described above, the fuel cell assembly includes the separator in which the first seal member and the second seal member made of elastomer are arranged on both surfaces in the thickness direction. Therefore, the manufacturing method of the laminated body of this invention is suitable as a manufacturing method of the structural member of a fuel cell.

  (4) Preferably, in the configuration of (3), the thin plate is a separator, and the first elastic member and the second elastic member are seal members.

  According to this structure, the separator which has a sealing member on thickness direction both sides can be manufactured, without curving a separator. Further, in the mold clamping process, the seal member formed on the first surface of the separator is not easily damaged.

  (5) Preferably, in the configuration of (4), the first elastic member includes a pedestal portion bonded to the thin plate, and a first peak portion protruding from the pedestal portion and having a curved surface, In the mold clamping step, at least the first peak portion may be compressed in the stacking direction.

  According to this configuration, by compressing the top of the first elastic member, the pressing force from the mold can be easily transmitted to the thin plate via the first elastic member.

  When a fuel cell is configured by stacking fuel cell assemblies, a seal member is disposed in a compressed state between separators of adjacent cell assemblies. In a state where the cell assemblies are stacked, if the compression rate of the seal member is small, the reaction force of the seal member is small, and the sealing performance between the separators may be reduced. In this regard, the first elastic member of this configuration has a pedestal portion and a first peak portion. The first mountain portion is easily crushed during compression. Therefore, according to the fuel cell assembly provided with the first elastic member of this configuration, even if the first elastic member is disposed between the separators with a relatively small compression rate, the sealing performance between the separators can be ensured.

  (6) Preferably, in the configuration of (5) above, in the mold clamping step, both the pedestal portion and the first peak portion may be compressed in the stacking direction.

  According to this configuration, the first elastic member can be compressed as a whole during mold clamping. For this reason, even if the compression rate of the 1st elastic member at the time of mold clamping is comparatively large, it is hard to concentrate stress inside the 1st elastic member, and the failure | damage of a 1st elastic member is suppressed.

  (7) Preferably, in the configuration of (4), the first elastic member includes a pedestal portion bonded to the thin plate, a first peak portion protruding from the pedestal portion and having a curved surface, and the first peak portion. And a second ridge that has a curved surface with a smaller radius of curvature than the radius of curvature of the first ridge, and at least the second ridge is compressed in the stacking direction in the mold clamping step. It is good to do.

  According to this configuration, by compressing the top of the first elastic member, the pressing force from the mold can be easily transmitted to the thin plate via the first elastic member.

  As described above, when a fuel cell is configured by stacking fuel cell assemblies, if the compression rate of the seal member disposed between the separators of adjacent cell assemblies is small, the sealing performance between the separators may be reduced. is there. On the other hand, if the compression ratio of the seal member is large, the internal stress of the seal member increases and the seal member may be damaged. In this regard, according to the first elastic member of the present configuration, the uppermost second peak portion is crushed at the time of low compression, and the first peak portion is crushed as the compression rate increases. Thereby, the sealing performance between adjacent separators can be ensured while suppressing an increase in internal stress due to compression.

  (8) Preferably, in the configuration of (7), all of the pedestal portion, the first peak portion, and the second peak portion may be compressed in the stacking direction.

  According to this configuration, the first elastic member can be compressed as a whole during mold clamping. For this reason, even if the compression rate of the 1st elastic member at the time of mold clamping is comparatively large, it is hard to concentrate stress inside the 1st elastic member, and the failure | damage of a 1st elastic member is suppressed.

It is a perspective view of a fuel cell provided with the fuel cell assembly of a first embodiment. It is a disassembled perspective view of the cell assembly. It is III-III sectional drawing of FIG. It is an up-down direction sectional view of the clamping state of the 1st metallic mold used for the 1st elastic member arrangement process of the manufacturing method of the cell assembly. It is an up-down direction sectional view of the second mold used for the temporary assembly assembly preparation process of the manufacturing method of the same cell assembly. It is an up-down direction sectional view of the 2nd metallic mold after inversion. It is an up-down direction sectional view of the mold clamping state of the 3rd metallic mold used for the mold clamping process and the 2nd elastic member formation process of the manufacturing method of the cell assembly. FIG. 8 is an enlarged view in a circle VIII in FIG. 7. It is the figure which piled up the section of the up-and-down direction of the 1st crevice, and the section of the up-and-down direction of the 1st seal member. It is the figure which piled up the cross section of the up-down direction of the upper 1st recessed part used in the manufacturing method of the fuel cell assembly of a second embodiment, and the cross section of the up-down direction of the 1st seal member. It is the figure which piled up the up-down direction cross section of the upper mold | type 1st recessed part used in the manufacturing method of the fuel cell assembly of 3rd embodiment, and the up-down direction cross section of the 1st seal member. It is a cross-sectional enlarged view of the peripheral part vicinity of the fuel cell assembly manufactured by the conventional method.

  Hereinafter, an embodiment of a manufacturing method of a layered product of the present invention is described. In the embodiment, the method for manufacturing a laminate according to the present invention is embodied as a method for manufacturing a fuel cell assembly.

<First embodiment>
[Configuration of fuel cell]
First, a configuration of a fuel cell including the fuel cell assembly of the present embodiment (hereinafter, appropriately abbreviated as “cell assembly”) will be described. In the following embodiments, the vertical direction corresponds to the “stacking direction” of the present invention, and the horizontal direction (front / rear / left / right direction) corresponds to the “plane direction” of the present invention.

  In FIG. 1, the perspective view of a fuel cell provided with the fuel cell assembly of this embodiment is shown. As shown in FIG. 1, the fuel cell 1 is configured by stacking a large number of cell assemblies 2. The fuel cell 1 is a polymer electrolyte fuel cell. A pair of end plates 13 and 14 are disposed at both ends of the large number of cell assemblies 2 in the vertical direction. Each of the pair of end plates 13 and 14 is made of stainless steel and has a rectangular plate shape.

  On the left edge of the fuel cell 1, from the rear to the front, an air supply member 10a that supplies air (oxidant gas), a cooling water supply member 12a that supplies cooling water, and hydrogen that supplies hydrogen (fuel gas) The supply member 11a is connected. Connected to the right edge of the fuel cell 1 are an air discharge member 10b for discharging air, a cooling water discharge member 12b for discharging cooling water, and a hydrogen discharge member 11b for discharging hydrogen from the front to the rear. As will be described later, the plurality of cell assemblies 2 are each formed with a plurality of communication holes. By connecting the communication holes in the stacking direction, air, hydrogen, and cooling water flow paths are formed in the fuel cell 1 in the stacking direction of the cell assembly 2.

[Configuration of fuel cell assembly]
Next, the configuration of the fuel cell assembly of this embodiment will be described. FIG. 2 is an exploded perspective view of the fuel cell assembly according to this embodiment. FIG. 3 is a cross-sectional view taken along line III-III in FIG. As shown in FIGS. 2 and 3, the cell assembly 2 includes an electrode member 3, a first separator 4 </ b> U, a second separator 4 </ b> D, a first seal member 5 </ b> U, and a second seal member 5 </ b> D. .

(Electrode member 3)
As shown in FIGS. 2 and 3, the electrode member 3 includes an MEA 30, an anode porous layer 31, and a cathode porous layer 32. The MEA 30 includes an electrolyte membrane, an anode catalyst layer, and a cathode catalyst layer. The electrolyte membrane is a perfluorinated sulfonic acid membrane and has a rectangular thin plate shape. Each of the anode catalyst layer and the cathode catalyst layer is formed including carbon particles supporting platinum. Each of the anode catalyst layer and the cathode catalyst layer has a rectangular thin plate shape. The anode catalyst layer is laminated on the lower surface of the electrolyte membrane. The cathode catalyst layer is laminated on the upper surface of the electrolyte membrane.

  The anode porous layer 31 is a gas diffusion layer. The anode porous layer 31 is made of sintered foam metal and has a rectangular thin plate shape. The anode porous layer 31 is laminated on the lower surface of the MEA 30. The cathode porous layer 32 is a gas diffusion layer. The cathode porous layer 32 is made of sintered foam metal and has a rectangular thin plate shape. The cathode porous layer 32 is laminated on the upper surface of the MEA 30.

(First separator 4U)
As shown in FIGS. 2 and 3, the first separator 4U is made of stainless steel and has a rectangular thin plate shape. The first separator 4U is stacked on the upper surface of the electrode member 3. Three communication holes 40U are provided in each of the left edge and the right edge of the first separator 4U. The first separator 4U includes an uneven portion 41U. The uneven portion 41U includes six rib portions 41UH and five flat portions 41UL. The rib portion 41UH extends in the left-right direction. The six rib portions 41UH are arranged in the front-rear direction. The flat ground portion 41UL is disposed between a pair of adjacent rib portions 41UH. The first separator 4U is included in the concept of the “thin plate” of the present invention. The upper surface of the first separator 4U corresponds to the “first surface” of the present invention, and the lower surface corresponds to the “second surface” of the present invention.

(Second separator 4D)
As shown in FIGS. 2 and 3, the second separator 4D is made of stainless steel and has a rectangular thin plate shape. The second separator 4D is stacked on the lower surface of the electrode member 3. Three communication holes 40D are provided in each of the left and right edges of the second separator 4D. The second separator 4D includes an uneven portion 41D. The uneven portion 41D includes six rib portions 41DH and five flat portions 41DL. The rib portion 41DH extends in the left-right direction. The six rib portions 41DH are arranged in the front-rear direction. The flat ground portion 41DL is disposed between a pair of adjacent rib portions 41UH.

(First seal member 5U)
The first seal member 5U is made of a solid rubber cross-linked product containing ethylene-propylene-diene rubber (EPDM) as a rubber component. The cross-linked product of the solid rubber is included in the concept of “elastomer” of the present invention. As shown in FIG. 2, the first seal member 5U has a rectangular frame shape. The first seal member 5U is provided with a communication hole 50U that communicates with the communication hole 40U of the first separator 4U.

  As shown in FIGS. 2 and 3, the first seal member 5U includes a pedestal portion 51U and a first peak portion 52U. The pedestal 51U is disposed so as to cover the peripheral edge of the upper surface of the first separator 4U. The pedestal 51U is bonded to the upper surface of the first separator 4U. The first mountain portion 52U protrudes from the upper surface of the pedestal portion 51U. The first peak portion 52U has a substantially semicircular curved surface in the vertical cross section. As shown in FIG. 1 and FIG. 2 by hatching, the first peak portion 52U is arranged so as to surround the peripheral edge portion of the first seal member 5U and the six communication holes 50U. Thereby, an annular seal line is formed. The first seal member 5U is included in the concept of the “first elastic member” of the present invention.

(Second seal member 5D)
The second seal member 5D is made of a solid rubber cross-linked product containing EPDM as a rubber component. As shown in FIG. 2, the second seal member 5D has a rectangular frame shape. The second seal member 5D is disposed so as to cover the peripheral edge portion of the lower surface of the first separator 4U. The second seal member 5D is bonded to the peripheral portion of the lower surface of the first separator 4U and the peripheral portion of the upper surface of the second separator 4D.

  The electrode member 3 is accommodated in the frame of the second seal member 5D. The inner edge of the frame of the second seal member 5 </ b> D is bonded to the peripheral edge of the electrode member 3. For this reason, the second seal member 5D seals the electrode member 3 from the outside. The electrode member 3, the first separator 4U, and the second separator 4D are bonded via a second seal member 5D. The second seal member 5D is provided with a communication hole 50D that communicates with the communication hole 40U of the first separator 4U. The second seal member 5D is included in the concept of the “second elastic member” of the present invention.

[Method of manufacturing fuel cell assembly]
Next, a method for manufacturing the fuel cell assembly according to this embodiment will be described. The manufacturing method of the fuel cell assembly of the present embodiment includes a first elastic member arranging step, a temporary assembly assembly preparing step, a mold clamping step, and a second elastic member forming step.

(First elastic member placement step)
FIG. 4 shows a cross-sectional view in the up-down direction of the first mold used in this process in a clamped state. As shown in FIG. 4, the first mold 60 includes an upper mold 601 and a lower mold 602. A recess 603 is provided in the lower surface of the upper mold 601. A recess 604 is provided on the upper surface of the lower mold 602.

  In this step, the first seal member 5U is disposed on the upper surface of the first separator 4U using the first mold 60. First, the first seal member precursor 5UF is disposed in the recess 604 of the lower mold 602. The first seal member precursor 5UF is formed by injection molding an uncrosslinked product of solid rubber containing EPDM as a rubber component. The first seal member precursor 5UF has the same shape as the first seal member 5U. Next, the first separator 4U is placed on the upper surface of the lower mold 602 so that the upper surface of the first separator 4U is on the lower side. On the upper surface (lower surface in FIG. 4) of the first separator 4U, a primer is applied to a region in contact with the first seal member precursor 5UF. And the upper mold | type 601 is arrange | positioned and the 1st metal mold | die 60 is clamped. At this time, the first separator 4U is accommodated in the recess 603. Then, the first mold 60 is heated to crosslink the first seal member precursor 5UF. By the crosslinking, the first seal member precursor 5UF becomes the first seal member 5U. In this way, the first seal member 5U is formed on the upper surface of the first separator 4U.

(Temporary assembly preparation process)
In this step, a temporary assembly 70 composed of the second seal member precursor 5DF, the electrode member 3, and the second separator 4D is placed in the mold. FIG. 5 shows a vertical sectional view of the second mold used in this process in a clamped state. As shown in FIG. 5, the second mold 61 includes an upper mold 611, a middle mold 612, and a lower mold 613.

  First, the second seal member precursor 5DF is disposed in the recess 614 surrounded by the lower mold 613 and the middle mold 612. The second seal member precursor 5DF is formed by injection molding an uncrosslinked product of solid rubber containing EPDM as a rubber component. The second seal member precursor 5DF has the same shape as the second seal member 5D. Next, the electrode member 3 is disposed in the frame of the second seal member precursor 5DF. Further, a second separator 4D is laminated on the second seal member precursor 5DF and the upper surface of the electrode member 3. On the lower surface of the second separator 4D, a primer is applied to a region in contact with the second seal member precursor 5DF. Then, the upper mold 611 is arranged and the second mold 61 is clamped. Then, the second mold 61 is turned upside down and the lower mold 613 disposed on the upper side is removed.

  FIG. 6 shows a vertical sectional view of the second mold after inversion. As shown in FIG. 6, in the second mold 61 after inversion, the upper mold 611 is disposed on the lower side, and the lower mold 613 is removed. In the recess 615 surrounded by the upper mold 611 and the middle mold 612, a temporary assembly 70 including the second seal member precursor 5DF, the electrode member 3, and the second separator 4D is disposed.

(Clamping process)
In this step, the first separator 4U having the first seal member 5U disposed on the upper surface is disposed in the mold, and the second seal member precursor 5DF is disposed on the lower surface side of the first separator 4U. Clamp the mold. The second seal member precursor 5DF is included in the concept of “elastomer material” of the present invention.

  In this embodiment, this process is performed using the upper mold 611, the middle mold 612, and the temporary assembly 70 after the temporary assembly assembly preparation process. FIG. 7 shows a vertical cross-sectional view of the third mold used in this step and the next second elastic member forming step in a clamped state. As shown in FIG. 7, the third mold 62 includes an upper mold 621, a middle mold 622, and a lower mold 623. Here, the middle mold 622 and the lower mold 623 are the middle mold 612 and the upper mold 611 of the second mold 61, respectively. That is, a temporary assembly 70 including the second seal member precursor 5DF, the electrode member 3, and the second separator 4D is disposed in the recess 624 surrounded by the lower mold 623 and the middle mold 622.

  First, the first separator 4U having the first seal member 5U formed on the upper surface is placed on the upper surfaces of the second seal member precursor 5DF and the electrode member 3. On the lower surface of the first separator 4U, a primer is applied to a region in contact with the second seal member precursor 5DF. Next, the upper mold 621 is disposed and the third mold 62 is clamped.

  The upper mold 621 is provided with a first recess 625 that accommodates the first seal member 5U. The first recess 625 opens downward. FIG. 8 shows an enlarged view in a circle VIII in FIG. FIG. 9 shows a diagram in which the vertical section of the first recess and the vertical section of the first seal member are overlapped. In FIG. 8, the first seal member before being accommodated in the first recess is indicated by a thin line.

  As shown in FIGS. 8 and 9, the vertical section of the first recess 625 has a step shape. The first recess 625 includes an outer portion 625a and an inner portion 625b having different heights in the stacking direction (length in the vertical direction). The height of the inner part 625b is larger than the height of the outer part 625a. The cross-sectional shape in the vertical direction of the first recess 625 is different from the cross-sectional shape in the vertical direction of the first seal member 5U before being accommodated in the first recess 625. That is, the height (La2) of the outer portion 625a is smaller than the height (La1) of the base portion 51U of the first seal member 5U before housing. The height (Lb2) of the inner side part 625b is smaller than the maximum height of the first seal member 5U before housing, that is, the total height (Lb1) of the pedestal part 51U and the first peak part 52U. Moreover, the opening width (front-rear direction length: Lc2) of the first recess 625 is larger than the width (front-rear direction length: Lc1) of the first seal member 5U before housing.

  When the first seal member 5U is accommodated in the first recess 625 during mold clamping, the first peak portion 52U is compressed downward by the inner portion 625b, and the pedestal portion 51U is compressed downward by the outer portion 625a. . Then, the compressed portion expands in the horizontal direction so as to escape into the gap 626 between the first seal member 5U and the first recess 625. The volume of the first recess 625 is substantially the same as the volume of the first seal member 5U. Therefore, the first seal member 5U is filled in substantially the entire first recess 625.

In the present embodiment, the compression rate of the pedestal 51U of the first seal member 5U during mold clamping is 10%. The compression rate of the first peak portion 52U of the first seal member 5U is 21%. Each compression rate was calculated by the following equations (1) and (2).
Compression rate of pedestal 51U of first seal member 5U = (La1-La2) / La1 × 100 (%) (1)
[La1: Height of the base portion 51U of the first seal member 5U before being housed in the first recess 625, La2: Height of the outer portion 625a of the first recess 625]
Compression rate of first peak portion 52U of first seal member 5U = (Lb1-Lb2) / Lb1 × 100 (%) (2)
[Lb1: Total height of the base portion 51U and the first peak portion 52U of the first seal member 5U before being housed in the first recess 625, Lb2: the height of the inner portion 625b of the first recess 625]
(Second elastic member forming step)
In this step, by heating the third mold 62 after clamping, the second seal member precursor 5DF is crosslinked to form the second seal member 5D on the lower surface of the first separator 4U (see above). (See FIG. 7). By the crosslinking, the second seal member precursor 5DF becomes the second seal member 5D. The second seal member 5D is bonded to the peripheral edge of the electrode member 3, the lower surface of the first separator 4U, and the upper surface of the second separator 4D. Further, when the mold is opened and the cell assembly 2 is taken out, the first seal member 5U is restored to the shape before being accommodated in the first recess 625. In this way, the cell assembly 2 of the present embodiment is manufactured.

[Function and effect]
Next, the effect of the manufacturing method of the fuel cell assembly of this embodiment will be described. According to the manufacturing method of the cell assembly 2 of the present embodiment, the upper mold 621 in which the first concave portion 625 is provided is used in the mold clamping process and the second elastic member forming process. The first recess 625 has an outer part 625a and an inner part 625b. When the first seal member 5U is accommodated in the first recess 625 during mold clamping, the first peak portion 52U is compressed downward by the inner portion 625b, and the pedestal portion 51U is compressed downward by the outer portion 625a. . Further, the compressed portion extends in the horizontal direction so as to escape into the gap 626 between the first seal member 5U and the first recess 625. When the mold is clamped, the first seal member 5U is compressed in the stacking direction, whereby the first separator 4U is pressed by the first seal member 5U. Thereby, in the 2nd elastic member formation process, even if the 2nd seal member precursor 5DF expand | swells, it can resist the pressing force from the lower surface side of the 1st separator 4U. Therefore, the curve of the first separator 4U toward the first seal member 5U can be suppressed.

  In the vertical cross section, the opening width (front-rear direction length: Lc2) of the first recess 625 is larger than the width of the first seal member 5U (maximum length in the front-rear direction: Lc1) before housing. Therefore, even if a positional shift occurs when the upper mold 621 is set in the mold clamping process, the opening end of the first recess 625 and the first seal member 5U are unlikely to contact each other. Therefore, damage to the first seal member 5U during mold clamping can be avoided.

  Thus, according to the manufacturing method of the fuel cell assembly of this embodiment, the cell assembly 2 can be manufactured without damaging the first seal member 5U and without bending the first separator 4U. .

  In the present embodiment, the first seal member 5U has a pedestal portion 51U and a first peak portion 52U. In the mold clamping process, when the first seal member 5U is accommodated in the first recess 625, both the pedestal portion 51U and the first peak portion 52U are compressed downward. By compressing the first peak portion 52U at the top of the first seal member 5U, the pressing force from the upper mold 621 can be easily transmitted to the first separator 4U via the first seal member 5U. Further, since not only the first peak portion 52U of the first seal member 5U but also the pedestal portion 51U is compressed, even if the compression rate of the first seal member 5U at the time of mold clamping is relatively large, the first seal member 5U Stress is less likely to concentrate inside, and damage to the first seal member 5U is suppressed.

  When the fuel cell is configured by stacking the cell assemblies 2 manufactured by the manufacturing method of the fuel cell assembly of the present embodiment, the first separator 4U and the second separator 4D of the adjacent cell assemblies 2 are not connected to each other. The seal member 5U is arranged in a compressed state. In the state where the cell assemblies 2 are stacked, if the compression rate of the first seal member 5U is small, the reaction force of the first seal member 5U becomes small, and the sealing performance between the first separator 4U and the second separator 4D may be reduced. There is. In this regard, in the first seal member 5U of the present embodiment, the first peak portion 52U is easily crushed during compression. Therefore, even if the first seal member 5U is disposed between the first separator 4U and the second separator 4D with a relatively small compression rate, the sealing performance can be ensured.

<Second embodiment>
The difference between the method for manufacturing the fuel cell assembly of the present embodiment and the method for manufacturing the fuel cell assembly of the first embodiment is the shapes of the first seal member and the first recess. Here, only differences will be described.

  FIG. 10 shows a view in which the vertical section of the first recess and the vertical section of the first seal member are overlapped. 10, parts corresponding to those in FIG. 9 are denoted by the same reference numerals. As shown in FIG. 10, the first seal member 5U includes a pedestal portion 51U, a first peak portion 52U, and a second peak portion 53U. The pedestal 51U is bonded to the upper surface of the first separator 4U (see FIG. 3 above). The first mountain portion 52U protrudes from the upper surface of the pedestal portion 51U. The first peak portion 52U has a substantially semicircular curved surface in the vertical cross section. The second mountain portion 53U is arranged so as to protrude from the first mountain portion 52U. The second mountain portion 53U has a substantially semicircular curved surface in the vertical cross section. The curvature radius R2 of the second peak portion 53U is smaller than the curvature radius R1 of the first peak portion.

  On the other hand, the vertical cross section of the first recess 625 has a substantially mortar shape. The first recess 625 includes an outer portion 625a and an inner portion 625b having different heights in the stacking direction (length in the vertical direction). The height of the inner part 625b gradually increases from the outer part 625a.

  The cross-sectional shape in the vertical direction of the first recess 625 is different from the cross-sectional shape in the vertical direction of the first seal member 5U before being accommodated in the first recess 625. That is, the height (La2) of the outer portion 625a is smaller than the height (La1) of the base portion 51U of the first seal member 5U before housing. The maximum height (Lb2) of the inner portion 625b is based on the maximum height of the first seal member 5U before housing, that is, the total height (Lb1) of the pedestal portion 51U, the first peak portion 52U, and the second peak portion 53U. Is also small. Moreover, the opening width (front-rear direction length: Lc2) of the first recess 625 is larger than the width of the first seal member 5U (maximum length in the front-rear direction: Lc1) before accommodation.

  When the first seal member 5U is accommodated in the first recess 625 during mold clamping, the first peak portion 52U and the second peak portion 53U are compressed downward by the inner portion 625b, and the pedestal portion 51U is compressed by the outer portion 625a. Compressed downward. Then, the compressed portion expands in the horizontal direction so as to escape into the gap 626 between the first seal member 5U and the first recess 625. The volume of the first recess 625 is substantially the same as the volume of the first seal member 5U. Therefore, the first seal member 5U is filled in substantially the entire first recess 625.

In the present embodiment, the compression rate of the pedestal 51U of the first seal member 5U during mold clamping is 10%. The compression rate of the first peak portion 52U and the second peak portion 53U of the first seal member 5U is 21%. Each compression rate was calculated by the following equations (3) and (4).
Compression rate of pedestal 51U of first seal member 5U = (La1-La2) / La1 × 100 (%) (3)
[La1: Height of the base portion 51U of the first seal member 5U before being housed in the first recess 625, La2: Height of the outer portion 625a of the first recess 625]
Compression rate of first peak portion 52U and second peak portion 53U of first seal member 5U = (Lb1-Lb2) / Lb1 × 100 (%) (4)
[Lb1: Total height of the base portion 51U, the first peak portion 52U, and the second peak portion 53U of the first seal member 5U before being housed in the first recess 625, Lb2: the inner portion 625b of the first recess 625 Maximum height of]
The method for manufacturing the fuel cell assembly according to the present embodiment has the same operational effects as the method for manufacturing the fuel cell assembly according to the first embodiment with respect to parts having the same configuration. In the present embodiment, the first seal member 5U includes a pedestal portion 51U, a first peak portion 52U, and a second peak portion 53U. In the mold clamping step, when the first seal member 5U is accommodated in the first recess 625, all of the pedestal 51U, the first peak 52U, and the second peak 53U are compressed downward. By compressing the second peak portion 53U at the top of the first seal member 5U, the pressing force from the upper mold 621 can be easily transmitted to the first separator 4U via the first seal member 5U. Further, since not only the first peak portion 52U and the second peak portion 53U of the first seal member 5U but also the pedestal portion 51U is compressed, even if the compression rate of the first seal member 5U during mold clamping is relatively large, Stress is less likely to concentrate inside the first seal member 5U, and damage to the first seal member 5U is suppressed.

  Further, in the state where the cell assemblies manufactured by the manufacturing method of the fuel cell assembly of the present embodiment are stacked, if the compression rate of the first seal member 5U is small, the reaction force of the first seal member 5U is reduced, and the first There is a possibility that the sealing performance between the separators arranged with the one sealing member 5U interposed therebetween may deteriorate. On the other hand, if the compression rate of the first seal member 5U is large, the internal stress of the first seal member 5U increases and the first seal member 5U may be damaged. In this regard, according to the first seal member 5U of the present embodiment, at the time of low compression, the uppermost second peak portion 53U is crushed, and the first peak portion 52U is crushed as the compression rate increases. Thereby, the sealing performance between adjacent separators can be ensured while suppressing an increase in internal stress due to compression.

<Third embodiment>
The difference between the method for manufacturing the fuel cell assembly of the present embodiment and the method for manufacturing the fuel cell assembly of the first embodiment is the shapes of the first seal member and the first recess. Here, only differences will be described.

  FIG. 11 shows a view in which the vertical section of the first recess and the vertical section of the first seal member are overlapped. 11, parts corresponding to those in FIG. 9 are denoted by the same reference numerals. As shown in FIG. 11, the first seal member 5U has a main body portion 54U and a third mountain portion 55U. The main body 54U is bonded to the upper surface of the first separator 4U (see FIG. 3 above). The third mountain portion 55U is disposed on the upper surface of the main body portion 54U. The width (length in the front-rear direction) of the third mountain portion 55U and the width (length in the front-rear direction) of the main body portion 54U are the same. The third mountain portion 55U has a substantially semicircular curved surface in the vertical cross section.

  On the other hand, the vertical cross section of the first recess 625 has a trapezoidal shape. The cross-sectional shape in the vertical direction of the first recess 625 is different from the cross-sectional shape in the vertical direction of the first seal member 5U before being accommodated in the first recess 625. That is, the height (vertical length: Lb2) of the first recess 625 in the stacking direction is the maximum height of the first seal member 5U before housing, that is, the total height of the main body portion 54U and the third mountain portion 55U. Smaller than (Lb1). Moreover, the opening width (front-rear direction length: Lc2) of the first recess 625 is larger than the width (Lc1) of the first seal member 5U before housing.

  When the first seal member 5U is accommodated in the first recess 625 at the time of mold clamping, the third peak portion 55U is compressed downward by the bottom 625c of the first recess 625. Then, the compressed portion expands in the horizontal direction so as to escape into the gap 626 between the first seal member 5U and the first recess 625. The volume of the first recess 625 is substantially the same as the volume of the first seal member 5U. Therefore, the first seal member 5U is filled in substantially the entire first recess 625.

In the present embodiment, the compression rate of the third peak portion 55U of the first seal member 5U at the time of mold clamping is 21%. The compression rate of the third mountain portion 55U was calculated by the following equation (5).
Compression rate of the third crest 55U of the first seal member 5U = (Lb1-Lb2) / Lb1 × 100 (%) (5)
[Lb1: Total height of the main body portion 54U and the third peak portion 55U of the first seal member 5U before being accommodated in the first recess portion 625, Lb2: height of the first recess portion 625]
The method for manufacturing the fuel cell assembly according to the present embodiment has the same operational effects as the method for manufacturing the fuel cell assembly according to the first embodiment with respect to parts having the same configuration. In the present embodiment, when the first seal member 5U is accommodated in the first recess 625 in the mold clamping step, the third mountain portion 55U is compressed downward. By compressing the top of the first seal member 5U, the pressing force from the upper mold 621 can be easily transmitted to the first separator 4U via the first seal member 5U.

<Others>
The embodiment of the method for manufacturing a laminate according to the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  In the above embodiment, the vertical direction corresponds to the “lamination direction” of the present invention, and the horizontal direction (front / rear / left / right direction) corresponds to the “plane direction” of the present invention. However, the correspondence between these directions is not particularly limited.

  In the said embodiment, the manufacturing method of the laminated body of this invention was embodied as a manufacturing method of a fuel cell assembly. However, the laminate is not limited to the constituent members of the fuel cell. The manufacturing method of the laminated body of this invention can be embodied as a manufacturing method of the laminated body used for various uses, such as a component member of a lithium ion battery and a capacitor.

  In addition, when the manufacturing method of the laminated body of the present invention is embodied as a manufacturing method of a fuel cell assembly, the material and shape of each member constituting the fuel cell assembly are not limited to the above embodiment. Absent. For example, the structure of the anode porous layer and the cathode porous layer constituting the electrode member is not particularly limited. As in the above-described embodiment, a single-layer structure including only the gas diffusion layer may be used, or a two-layer structure including the gas diffusion layer and the gas flow path layer may be used.

  The material, shape, and the like of the members constituting the laminate are not limited to the above embodiment. For example, the material of the thin plate may be metal or resin. Further, the shape of the thin plate may be a flat plate shape having no uneven portion. In the above embodiment, both the first elastic member and the second elastic member are made of a solid rubber cross-linked product containing EPDM as a rubber component. However, the first elastic member and the second elastic member may be made of an elastomer, and the type of elastomer is not particularly limited. The materials of the first elastic member and the second elastic member may be different. In addition to the rubber component, the elastomer may contain a crosslinking agent, a crosslinking aid, an adhesive component, and the like. Rubber components suitable as a sealing member for fuel cells include EPDM, ethylene-propylene rubber (EPM), acrylonitrile-butadiene rubber (NBR), hydrogenated acrylonitrile-butadiene rubber (H-NBR), styrene-butadiene rubber ( SBR) and butadiene rubber (BR).

  The shapes of the first elastic member and the second elastic member are not particularly limited. The shape and size of the first recess formed in the mold that accommodates the first elastic member is such that the first elastic member can be compressed in the stacking direction when the mold is clamped, and the compressed first elastic member What is necessary is just to determine suitably so that can extend | expand in a surface direction. For example, the height of the first recess in the stacking direction may be designed to be smaller than the height of the first elastic member in the stacking direction so that the top of the first elastic member can be compressed in the stacking direction. In this case, it is desirable that the compression ratio of the top portion of the first elastic member in the mold clamping process is 10% or more and 50% or less. It is more preferable that it is 20% or more and 40% or less.

As in the first and second embodiments, when the first elastic member is composed of the pedestal portion and the first peak portion protruding from the upper surface, the pedestal portion is compressed in the stacking direction in the mold clamping process. You don't have to be. In the case where the pedestal is compressed in the stacking direction, the compression rate is preferably 5% or more and 30% or less. It is more preferable to make it 20% or less. The compression rate of the first elastic member is expressed by the following equation (6) based on the height (L1) of the portion to be compressed in the stacking direction and the corresponding height (L2) of the first recess in the stacking direction. It may be calculated by the following.
Compression rate of first elastic member = (L1−L2) / L1 × 100 (%) (6)
In the said embodiment, the 1st elastic member was formed in the 1st elastic member arrangement | positioning process by carrying out the cross-linking adhesion | attachment of the precursor which preformed the uncrosslinked material of the elastomer previously on the 1st surface of a thin plate. In this case, it is not always necessary to apply a primer to the first surface of the thin plate. On the other hand, in the first elastic member arranging step, a first elastic member made of elastomer may be bonded to the first surface of the thin plate using an adhesive or the like.

  In the above embodiment, in the mold clamping step, a precursor obtained by preforming an uncrosslinked elastomer in advance is disposed on the second surface side of the thin plate. However, the elastomer material disposed on the second surface side of the thin plate may be a fluid composition instead of a preform. It is not always necessary to apply a primer to the second surface of the thin plate. The preforming of the elastomer uncrosslinked product may be performed by other molding methods such as press molding in addition to injection molding.

  The method for producing a laminate of the present invention is useful as a method for producing a laminate for sealing a gas or liquid, such as a constituent member of a fuel cell, a constituent member of a lithium ion battery or a capacitor.

1: fuel cell, 2: cell assembly (laminated body), 3: electrode member, 4U: first separator (thin plate), 4D: second separator, 5U: first seal member (first elastic member), 5D: first Two seal members (second elastic member), 5UF: first seal member precursor, 5DF: second seal member precursor (elastomer material), 10a: air supply member, 10b: air discharge member, 11a: hydrogen supply member, 11b: hydrogen discharge member, 12a: cooling water supply member, 12b: cooling water discharge member, 13, 14: end plate, 31: anode porous layer, 32: cathode porous layer, 40U, 40D: communication hole, 41U, 41D: uneven part, 41UH, 41DH: rib part, 41UL, 41DL: flat part, 50U, 50D: communication hole, 51U: pedestal part, 52U: first mountain part, 53U: second mountain part, 54U: Body part, 55U: Third mountain part, 60: First mold, 61: Second mold, 62: Third mold, 70: Temporary assembly, 601: Upper mold, 602: Lower mold, 603, 604: recessed part, 611: upper mold, 612: middle mold, 613: lower mold, 614, 615: recessed part, 621: upper mold, 622: middle mold, 623: lower mold, 624: recessed part, 625: first recessed part, 625a: Outer part, 625b: inner part, 625c: bottom part, 626: gap.

Claims (6)

And the thin a separator, a manufacturing method of a fuel cell assembly having a first elastic member and the second elastic member is a sealing member made disposed et elastomer in the thickness direction both sides of the thin plate, and
A direction in which the first elastic member, the thin plate, and the second elastic member are stacked is a stacking direction, and a direction orthogonal to the stacking direction is a plane direction,
Of the both sides of the thin plate in the laminating direction, one is a first surface, the other is a second surface,
The elastomer uncrosslinked product as an elastomer material,
A first elastic member disposing step of disposing the first elastic member on the first surface of the thin plate;
A mold clamping step in which the thin plate in which the first elastic member is disposed on the first surface is disposed in the mold, and the elastomer material is disposed on the second surface side of the thin plate to perform the mold clamping.
A second elastic member forming step of forming a second elastic member on the second surface by crosslinking the elastomer material by heating the mold after clamping;
Have
The mold has a first recess for accommodating the first elastic member,
In mold clamping step, wherein the first elastic member, the manufacturing method of the fuel cell assembly, characterized in that while being compressed in the laminated direction and extending in said surface direction is accommodated in said first recess. 2. The method of manufacturing a fuel cell assembly according to claim 1, wherein an opening width of the first recess in the surface direction is larger than a width of the first elastic member in the surface direction before the mold clamping step. The first elastic member has a pedestal portion bonded to the thin plate, and a first peak portion protruding from the pedestal portion and having a curved surface,
The method of manufacturing a fuel cell assembly according to claim 1 or 2 , wherein at least the first peak portion is compressed in the stacking direction in the mold clamping step. The method of manufacturing a fuel cell assembly according to claim 3 , wherein in the mold clamping step, both the pedestal portion and the first peak portion are compressed in the stacking direction. The first elastic member includes a pedestal portion bonded to the thin plate, a first peak portion protruding from the pedestal portion and having a curved surface, and a curvature smaller than the curvature radius of the first peak portion protruding from the first peak portion. A second peak having a curved surface with a radius,
3. The method of manufacturing a fuel cell assembly according to claim 1, wherein at least the second peak portion is compressed in the stacking direction in the mold clamping step. The method of manufacturing a fuel cell assembly according to claim 5 , wherein in the mold clamping step, all of the pedestal portion, the first peak portion, and the second peak portion are compressed in the stacking direction.

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