JP2008166237A - Fuel cell, seal-integrated member structuring fuel cell, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain cross leak in a fuel cell of a stack structure. <P>SOLUTION: The seal-integrated member structures a fuel cell by lamination. For the manufacturing method of the seal-integrated member having a lamination member and a seal member integrated with an end part of the lamination member to seal between adjacent members at lamination, a lamination member containing at least an electrolyte membrane, a first diffusion layer arranged on one side of the electrolyte membrane and a second diffusion layer arranged on the other side of the electrolyte membrane is prepared, and reinforcing members for reinforcing the seal member from inside are prepared. The reinforcing members are supported with the use of the end part of the lamination member, and the seal member is injection molded so as to cover the supported part with at least the use of the lamination member among the reinforcing members. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cell, a seal integrated member constituting the fuel cell, and a manufacturing method thereof.

  In a fuel cell, for example, a polymer electrolyte fuel cell, a reactive gas (a fuel gas containing hydrogen and an oxidizing gas containing oxygen) is respectively applied to two electrodes (a fuel electrode and an oxygen electrode) facing each other with an electrolyte membrane interposed therebetween. By supplying and causing an electrochemical reaction, the chemical energy of the substance is directly converted into electrical energy. As a main structure of such a fuel cell, a so-called stack structure is known in which laminated members including substantially flat electrolyte membranes and separators are alternately laminated and fastened in the lamination direction.

  By the way, as a fuel cell having the above-mentioned stack structure, there is known a technique in which a sealing member is integrally formed at the end of a laminated member in which a membrane electrode assembly is sandwiched between gas diffusion layers from both sides, and a reinforcing member is provided inside the sealing member. (For example, Patent Document 1).

JP 2001-102072 A International Publication WO01 / 017048 JP 2003-68319 A JP 2002-329512 A JP 2004-142127 A JP 2006-210234 A

  However, in the above prior art, one reaction gas (for example, oxidizing gas) passes between the electrolyte membrane and the seal member and mixes with the other reaction gas (for example, fuel gas), so-called cross. There was a risk of causing a leak.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to suppress cross leak in a fuel cell having a stack structure.

  In order to solve the above-described problem, a first aspect of the present invention is a seal integrated member that is stacked to constitute a fuel cell, and is integrated with a stacked member and an end portion of the stacked member. A method for producing a seal integral member having a seal member for sealing between adjacent members. The manufacturing method according to the first aspect includes a denatured membrane, a first diffusion layer disposed on one side of the electrolyte membrane, and a second diffusion layer disposed on the other side of the electrolyte membrane. The laminated member including at least, the reinforcing member for reinforcing the seal member from the inside is prepared, the reinforcing member is supported using an end portion of the laminated member, and at least the reinforcing member The sealing member is formed so as to cover a portion supported using the laminated member.

  According to the manufacturing method according to the first aspect, since the reinforcing member is supported by using the end portion of the laminated member and the sealing member is molded, it is not necessary to support the reinforcing member from the outside, and among the reinforcing members The supported part is not exposed to the outside. As a result, corrosion of the reinforcing member can be suppressed and cross leakage can be suppressed.

  In the manufacturing method according to the first aspect, a part of the end portion of the laminated member extends outward from the other part, and the reinforcing member is supported by overlapping the extending part. Also good.

  In the manufacturing method according to the first aspect, the reinforcing member may be supported using at least the first diffusion layer among the laminated members, and at least the first diffusion layer and the second layer. The diffusion layer may be used. In this case, the reinforcing member is supported by using the diffusion layer having a relatively strong strength, so that the reinforcing member can be positioned with high accuracy.

  In the manufacturing method according to the first aspect, the reinforcing member may be supported using at least the electrolyte membrane among the laminated members.

  In the manufacturing method according to the first aspect, when the reinforcing member is supported, the reinforcing member may be bonded to the laminated member. In this way, since the reinforcing member can be positioned more reliably, the integrated seal member can be manufactured with high accuracy. Furthermore, it is possible to further suppress the cross leak by suppressing the seal member from being deformed in the surface direction of the laminated member.

  In the manufacturing method according to the first aspect, in the molding of the seal member, the seal member has a first seal line around a power generation region in the laminated member, and the reinforcement is inside the first seal line. You may form so that a member may not be exposed. By doing so, the reinforcing member is not exposed to the reaction gas or the generated water, so that corrosion of the reinforcing member can be suppressed and cross leakage can be suppressed.

  In the manufacturing method according to the first aspect, in the molding of the seal member, the seal member has a second seal line around a manifold hole arranged outside the laminated member, and the second seal The reinforcing member may be formed so as not to be exposed inside the line. In this way, the reinforcing member is not exposed to the reaction gas or the cooling medium, and therefore, corrosion of the reinforcing member can be suppressed and cross leakage can be suppressed.

  A 2nd aspect provides the seal integrated member which is laminated | stacked and comprises a fuel cell. The seal integrated member according to the second aspect includes an electrolyte membrane, a first diffusion layer disposed on one side of the electrolyte membrane, and a second diffusion layer disposed on the other side of the electrolyte membrane. , And a laminated member that includes at least a laminated member that seals between adjacent members when laminated, a seal member that is integrated with an end of the laminated member, and an end of the laminated member And a reinforcing member for reinforcing the sealing member from the inside, and at least a portion of the reinforcing member that is supported by using the laminated member is covered with the sealing member.

  According to the seal integrated member according to the second aspect, since the reinforcing member is supported using the laminated member, deformation of the seal member is suppressed. As a result, the sealing performance is improved and gas leakage and cross leakage can be suppressed.

  The seal integrated member according to the second aspect of the present invention can be realized in various aspects, like the manufacturing method according to the first aspect.

  In addition to this, the present invention also relates to a seal integrated member manufactured by the manufacturing method according to the first aspect, a fuel cell configured by stacking a plurality of seal integrated members, or the second aspect. The present invention can be realized in various modes including a fuel cell configured by stacking a plurality of seal integrated members and a plurality of seal integrated members with a separator interposed therebetween, and a vehicle equipped with such a fuel cell.

  Hereinafter, a fuel cell, an assembly constituting the fuel cell, and a seal integrated member constituting the fuel cell will be described based on examples with reference to the drawings.

A. Example:
-Configuration of Fuel Cell A schematic configuration of a fuel cell according to an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram showing a configuration of a fuel cell in an embodiment. FIG. 2 is an explanatory diagram illustrating a configuration of the seal integrated member in the embodiment.

  The fuel cell 10 has a stack structure in which a plurality of separators 14 and a plurality of seal integrated members 12 are alternately stacked. Reference numeral 11 in FIG. 1 indicates a part of the stack structure, and FIG. 1 shows an enlarged configuration of the part 11.

  The fuel cell 10 has a plurality of manifolds that penetrate the stack structure. Each manifold is a flow path responsible for supply / discharge of hydrogen as a fuel gas, air as an oxidizing gas, and cooling water. Each manifold is formed by a separator 14 and manifold holes 16 a to 16 f provided in the peripheral edge portion of the seal integrated member 12. The manifold hole 16a is a hydrogen supply port, and the manifold hole 16b is a hydrogen discharge port. The manifold hole 16c is a cooling water supply port, and the manifold hole 16d is a cooling water discharge port. The manifold hole 16e is an air supply port, and the manifold hole 16f is an air discharge port.

  The separator 14 is a three-layer laminated separator formed by laminating three metal (for example, stainless steel) thin plates, that is, a cathode plate 14a, an intermediate plate 14b, and an anode plate 14c. The cathode plate 14a is in contact with the cathode side (lower side in FIG. 1) of the seal integrated member 12, and the anode plate 14c is stacked in contact with the anode side (upper side in FIG. 1) of the seal integrated member 12.

  The separator 14 supplies hydrogen supplied via the manifold hole 16a to the anode side of the laminated member 30 described later, and supplies air supplied via the manifold hole 16e to the cathode side of the laminated member 30 described later. Have The separator 14 also realizes a function of collecting electricity generated by the seal integrated member 12 and a function of cooling by supplying cooling water to the intermediate plate 14b via the manifold hole 16c. Further, the separator 14 has a structure for guiding the fuel gas and the cooling water to the respective discharge manifold holes. In addition, as the separator 14, the thing of arbitrary structures other than a three-layer lamination type can be used.

  The seal integrated member 12 includes a laminated member 30, a seal member 40, and a reinforcing member 20. FIG. 2 shows a cross-sectional view (II cut surface in FIG. 1) of the seal integrated member 12.

  As shown in FIG. 2, the laminated member 30 is disposed in contact with the electrolyte membrane 32, the anode-side diffusion layer 34 a disposed in contact with the anode-side surface of the electrolyte membrane 32, and the cathode-side surface of the electrolyte membrane 32. The cathode side diffusion layer 34b, the anode side porous body 36a, and the cathode side porous body 36b are configured. The anode side porous body 36a is disposed on the anode side of the electrolyte membrane 32 with the anode side diffusion layer 34a interposed therebetween, and the cathode side porous body 36b is disposed on the cathode side of the electrolyte membrane 32 with the cathode side diffusion layer 34b interposed therebetween. Yes. The cathode side porous body 36 b is in contact with the separator 14 disposed on the cathode side of the seal integrated member 12. The anode side porous body 36 a contacts the separator 14 disposed on the anode side of the seal integrated member 12.

  The anode side porous body 36a and the cathode side porous body 36b are formed of a porous material having gas diffusibility and conductivity such as a metal porous body. The anode-side porous body 36a and the cathode-side porous body 36b have a higher porosity than the anode-side diffusion layer 34a and the cathode-side diffusion layer 34b described above, and the gas flow resistance therein is the anode-side diffusion layer 34a and the cathode-side diffusion layer. Those below 34b are used and function as a flow path for the reaction gas to flow as will be described later. The anode side porous body 36 a and the cathode side porous body 36 b have a size corresponding to the power generation region of the laminated member 30.

  The anode side diffusion layer 34a and the cathode side diffusion layer 34b are formed of, for example, a carbon cloth woven with a yarn made of carbon fiber, or carbon paper or carbon felt. As shown in FIG. 2, the anode side diffusion layer 34a has the same size as the anode side porous body 36a and the cathode side porous body 36b. The cathode side diffusion layer 34b is slightly larger than the anode side diffusion layer 34a in both the vertical direction and the horizontal direction.

  As shown in FIG. 2, the electrolyte membrane 32 has substantially the same size as the cathode side diffusion layer 34b. As described above, the cathode-side diffusion layer 34b and the electrolyte membrane 32 are larger in both the vertical and horizontal directions than the anode-side porous body 36a, the cathode-side porous body 36b, and the anode-side diffusion layer 34a. Therefore, in the laminated member 30, the cathode-side diffusion layer 34b and the electrolyte membrane 32 have outer peripheral ends extending outside the outer peripheral ends of the porous bodies 840 and 850 and the anode-side diffusion layer 34a (FIG. 2). That is, among the members constituting the laminated member 30, the members (in the present embodiment, the electrolyte membrane 32 and the cathode side diffusion layer 34 b) used to support the reinforcing member 20 as described later include the laminated member 30. The vicinity of the outer peripheral end extends in the plane direction of the laminated member 30 (in the direction orthogonal to the laminated direction) from the other members constituting. In the cathode side diffusion layer 34b and the electrolyte membrane 32, portions extending outside the outer peripheral ends of the porous bodies 840 and 850 are referred to as peripheral portions.

  The electrolyte membrane 32 is an ion exchange membrane formed of, for example, a fluorine resin material or a hydrocarbon resin material and having good ionic conductivity in a wet state. In the electrolyte membrane 32, a catalyst layer is applied to the surfaces on both sides of the inner region from the peripheral edge (the illustration of the catalyst layer is omitted). The catalyst layer includes, for example, platinum or an alloy made of platinum and another metal.

  As shown in FIG. 2, the seal member 40 is integrated with the outer peripheral end of the laminated member 30. When the seal integrated member 12 and the separator 14 are laminated, the seal member 40 is in close contact with the adjacent separator 14 and seals between the separators 14, and reacts with a reactive gas (hydrogen and air in this embodiment) or cooling. Prevent water leakage.

  The seal member 40 includes ribs RB that form a first seal line surrounding the entire circumference of the power generation region of the laminated member 30 and a second seal line surrounding the entire circumference of each manifold hole. Have on both sides.

  The seal member 40 is formed of a material having gas impermeability, elasticity, and heat resistance in the operating temperature range of the fuel cell, for example, an elastic member such as rubber or elastomer. Specifically, silicon rubber, butyl rubber, acrylic rubber, natural rubber, fluorine rubber, ethylene / propylene rubber, styrene elastomer, fluorine elastomer and the like can be used.

  The seal member 40 is integrated by impregnating the end portion of the laminated member 30 as indicated by a symbol CC in FIG. More specifically, the anode-side porous body 36a, the cathode-side porous body 36b, and the anode-side diffusion layer 34a of the laminated member 30 are impregnated with the molding material of the seal member 40 (described above) in a small portion of the outer peripheral end. (FIG. 2). On the other hand, in the laminated member 30, the electrolyte membrane 32 and the cathode-side diffusion layer 34b each have a peripheral edge extending inside the seal member 40 (FIG. 2). Thus, the sealing performance between the sealing member 40 and the laminated member 30 is ensured by integrating the sealing member 40 at the end of the laminated member 30.

  The reinforcing member 20 is a member for reinforcing the seal member 40 from the inside, and is formed using a resin film such as polyethylene, for example. The entire surface of the reinforcing member 20 is covered with a seal member 40 except for an outer end (described later). The configuration of the reinforcing member 20 will be described later when the manufacturing method of the seal integrated member 12 is further described.

-Operation | movement of a fuel cell With reference to FIG. 3, operation | movement of the fuel cell 10 which concerns on an Example is demonstrated. FIG. 3 is an explanatory diagram showing the flow of the oxidizing gas in the fuel cell. In order to make the drawing easier to see, FIG. 3 shows a state in which two separators 14 and two seal integrated members 12 are alternately laminated. FIG. 3 shows a cross-sectional view corresponding to the II cross section in FIG.

  The fuel cell 10 is supplied with oxidizing gas (air in the present embodiment) into the manifold hole 16e for supplying the oxidizing gas, and with fuel gas (hydrogen in this embodiment) into the manifold hole 16a for supplying the fuel gas. Power generation. In addition, the cooling medium is supplied to the cooling medium supply manifold hole 16c to the fuel cell 10 during power generation in order to suppress the temperature rise of the fuel cell 10 due to heat generated by power generation.

The oxidizing gas supplied to the manifold hole 16e is supplied from the manifold hole 16e to the cathode-side porous body 36b through the oxidizing gas supply channel 141 formed in the seal integrated member 12 as shown by an arrow in FIG. The The oxidizing gas supply channel 141 is formed by comb-shaped slits (FIG. 1) formed in the intermediate plate 14b and holes (FIG. 1) formed in the cathode plate 14a. The oxidizing gas supplied to the cathode side porous body 36b flows inside the cathode side porous body 36b functioning as a flow path for the oxidizing gas. The oxidizing gas passes through the oxidizing gas discharge channel 142 formed in the seal integrated member 12 and is discharged to the oxidizing gas discharge manifold hole 16f. The oxidizing gas discharge channel 142 is formed by the oxidizing gas supply channel 141, the comb-shaped slits formed in the above-described intermediate plate 14b, and the holes formed in the cathode plate 14a. A part of the oxidizing gas flowing through the cathode side porous body 36b diffuses over the entire cathode side diffusion layer 34b in contact with the cathode side porous body 36b, and the cathode reaction (for example, 2H ⁺ + 2e ⁻ + (1 / 2) O ₂ → H ₂ O)

Although not shown, fuel gas is supplied / discharged in the same manner as the oxidizing gas. Specifically, the fuel gas supplied to the fuel gas supply manifold hole 16a is supplied from the manifold hole 16a to the anode-side porous body 36a through the fuel gas supply passage formed in the separator 14. The fuel gas supplied to the anode side porous body 36a flows in the anode side porous body 36a functioning as a fuel gas flow path. The fuel gas passes through the fuel gas discharge passage formed in the seal integrated member 12 and is discharged into the fuel gas discharge manifold hole 16b. A part of the oxidizing gas flowing through the anode-side porous body 36a diffuses over the entire anode-side diffusion layer 34a in contact with the anode-side porous body 36a, and the anode reaction (for example, H ₂ → 2H ⁺ + 2e ⁻ ).

  The cooling medium supplied to the cooling medium supply manifold hole 16 c is supplied from the manifold hole 16 c to the cooling medium flow path formed in the separator 14. The cooling medium flow path is formed by the slit (FIG. 1) formed in the intermediate plate 14b described above, and one end communicates with the manifold hole 16c for supplying the cooling medium and the other end communicates with the manifold hole 16d for discharging the cooling medium. ing. The cooling medium supplied to the cooling medium flow path flows from one end of the cooling medium flow path to the other end, and is discharged to the cooling medium discharge manifold hole 16d.

-Manufacturing method of seal integrated member:
With reference to FIGS. 4-8, the manufacturing method of the seal integrated member 12 which has the structure mentioned above is demonstrated. FIG. 4 is a flowchart showing manufacturing steps of the seal integrated member in the embodiment. FIG. 5 is a front view of the MEGA in the embodiment. FIG. 6 is a front view of the reinforcing member in the embodiment. FIG. 7 is a diagram for explaining the manufacture of the seal integrated member in the embodiment. FIG. 8 is a view showing a mold in the example. FIG. 7 corresponds to the FF cross section in FIG.

  First, the MEGA 35 is prepared (step S102). The MEGA 35 is obtained by integrally bonding an anode side diffusion layer 34a and a cathode side diffusion layer 34b to both surfaces of the above-described electrolyte membrane 32 by hot pressing in advance. The cathode side diffusion layer 34b is hot-pressed so as to exactly overlap the cathode side surface of the electrolyte membrane 32. As shown in FIG. 5, the anode-side diffusion layer 34 a is hot-pressed on the anode-side surface of the electrolyte membrane 32 so that the outer peripheral end thereof is located inside the outer peripheral end of the electrolyte membrane 32 by the length W. . In FIG. 5, a portion (peripheral part) of the electrolyte membrane 32 and the cathode side diffusion layer 34 b that extends outward from the outer peripheral end of the anode side diffusion layer 34 a is hatched.

  Next, the reinforcing member 20 is prepared (step S104). As shown in FIG. 6, the reinforcing member 20 has a first hole HL1 and a plurality of second holes HL2. The first hole HL <b> 1 is formed in the substantially central portion of the reinforcing member 20 so as to be substantially equal to the MEGA 35. Strictly speaking, the first hole HL1 is formed to be slightly larger than the anode side diffusion layer 34a of the MEGA 35 and slightly smaller than the electrolyte membrane 32 and the cathode side diffusion layer 34b of the MEGA 35. The plurality of second holes HL2 are formed at positions and sizes corresponding to the manifold holes 16a to 16f (FIG. 1) provided in the seal member 40 to be formed. Strictly speaking, in order to cover the wall surface forming the second hole HL2 of the reinforcing member 20 with the seal member 40, the second hole HL2 is slightly smaller than the manifold holes 16a to 16f provided in the seal member 40. It is formed small.

  Here, in the reinforcing member 20, an outer peripheral end is referred to as an outer end, and an end forming the first hole HL1 is referred to as an inner end.

  When the MEGA 35 and the reinforcing member 20 are prepared, the MEGA 35 and the reinforcing member 20 are bonded (step S106). Specifically, the MEGA 35 and the reinforcing member 20 are overlapped and bonded by hot pressing so that the inner end of the reinforcing member 20 is positioned on the peripheral edge of the MEGA 35 (hatched portion in FIG. 5). In FIG. 6, a region indicated by a broken line indicates a region overlapping with the peripheral edge of the MEGA 35. A case where the MEGA 35 and the reinforcing member 20 are bonded together is called a MEGA assembly. For example, this step may be performed at the same time when the MEGA 35 is manufactured by hot pressing the diffusion layers 34a and 34b on the electrolyte membrane 32 in step S102.

  When the MEGA assembly is prepared, a mold for integral molding is prepared (step S108). The mold has an upper mold 910 and a lower mold 920 as shown in FIG. As shown in FIGS. 7 and 8, the lower mold 920 has a cavity shape that matches the outer shape of the seal member 40 to be formed. Further, as shown in FIGS. 7 and 8, the upper mold 910 and the lower mold 920 are formed with protruding portions PJ corresponding to the manifold holes 16 a to 16 f provided in the seal member 40 to be formed. . The upper mold 910 has a molding material inlet SH formed in the protrusion PJ.

  Next, the cathode-side porous body 36b is disposed on the lower mold 920 (step S110). The MEGA assembly is placed over the placed cathode-side porous body 36b (Step S112). The MEGA assembly is positioned on the cathode side porous body 36b such that the peripheral edge of the MEGA 35 protrudes outside the cathode side porous body 36b.

  The anode side porous body 36a is disposed so as to overlap the disposed MEGA assembly (step S114). The anode side porous body 36a is disposed in a region inside the peripheral edge of the MEGA 35, that is, a region corresponding to the power generation region.

  Thus, when all the laminated members 30 are arranged in the lower mold, the mold is clamped with a predetermined mold pressure (step S116). FIG. 7B shows a state where the lower mold 920 and the upper mold 910 are clamped. In the state where the mold is clamped, the vicinity of the outer end of the reinforcing member 20 is sandwiched between the upper mold 910 and the lower mold 920 (FIG. 7B: T1). On the other hand, the vicinity of the inner end of the reinforcing member 20 is bonded to the peripheral edge of the electrolyte membrane 32 (FIG. 7B: T2). Thus, the reinforcement member 20 is supported in the mold by fixing the vicinity of the outer end and the vicinity of the inner end of the reinforcement member 20. In the state where the mold is clamped, a space SP having the shape of the seal member 40 is formed in the mold (FIG. 7B).

  In this space SP, injection molding of the seal member 40 is performed (step S118). Specifically, after the liquid rubber as the molding material of the seal member 40 is introduced into the space SP from the above-described inlet SH, the vulcanization process is performed.

  In this injection molding, the injection pressure of the molding material is controlled so that the lamination member 30 and the seal member 40 are integrated by impregnating the end portion of the lamination member 30 with the molding material (region CC in FIG. 2).

  When the seal member 40 is injection-molded, the mold is opened, the seal integrated member 12 is taken out, and the outer end portion of the reinforcing member 20 protruding from the seal member 40 is cut (step S120).

  According to the present embodiment described above, the reinforcing member 20 is fixed and supported near the outer end using a mold, and the inner end is fixed and supported using the electrolyte membrane 32 and the anode side diffusion layer 34a. At the time of injection molding of the member 40, the reinforcing member 20 is positioned in the mold. Furthermore, deformation and displacement of the reinforcing member 20 due to the injection pressure during injection molding are suppressed. It is possible to manufacture the seal integrated member 12 in which the reinforcing member 20 is accurately arranged at a target position inside the seal member 40.

  When the position of the reinforcing member 20 in the seal member 40 deviates from the target position, the sealing performance by the rib RB of the seal member 40 varies. For example, if the distance from the rib RB to the reinforcing member 20 differs from the target, the amount of deformation when the same pressing force is applied and the characteristics of the rib RB such as the reaction force when the same deformation occurs are different, and the desired seal Performance may not be obtained. As a result, a gas leak or a cross leak can occur in the fuel cell.

  In this embodiment, since the reinforcing member 20 can be accurately placed at the target position inside the seal member 40, variation in the seal performance of the rib RB of the seal member 40 can be suppressed, stable sealing performance can be secured, gas leakage and Cross leak can be suppressed.

  Further, in the present embodiment, the reinforcing member 20 is covered with the seal member 40 inside the fuel cell 10 inside the first seal line and inside the second seal line, and is exposed. Not. As a result, the reinforcing member 20 is not exposed to the reaction gas or generated water inside the first seal line or exposed to the reaction gas or cooling water inside the second seal line. As a result, in the present embodiment, corrosion of the reinforcing member 20 can be suppressed and cross leakage can be suppressed.

  For ease of understanding, an example of a conventional configuration will be described with reference to FIGS. 9 to 11 as an example of a seal integrated member 120 as a comparative example. FIG. 9 is a diagram for explaining the manufacture of the seal integrated member in the comparative example. FIG. 10 is a view showing a molding die in a comparative example. FIG. 11 is a diagram illustrating a configuration of a seal integrated member in a comparative example.

  In the comparative example, the MEGA 350 has the same electrolyte membrane 320 and cathode-side diffusion layer 340b as the anode-side diffusion layer 34a. The electrolyte membrane 320 and the cathode-side diffusion layer 340b are used to fix and support the reinforcing member 20. Not used.

  As shown in FIGS. 9 and 10, a plurality of positioning pins 911 and 922 are provided on the upper mold 910 and the lower mold 920 of the molding die in the comparative example, respectively. The positioning pins 911 and 922 are provided at positions corresponding to the vicinity of the inner end of the reinforcing member 20 on the inner side of the first seal line. In the clamped state, the vicinity of the inner end of the reinforcing member 20 is fixed by the positioning pins 911 and 922, and the reinforcing member 20 is positioned (FIG. 9B: T2). The other configuration is the same as that of the embodiment, and the description is omitted.

  In the seal integrated member 12 in the comparative example, as shown in FIG. 11, the hole HL remains inside the first seal line in the seal member 400. The hole HL is a hole formed by the positioning pins 911 and 921. Therefore, the reinforcing member 20 is exposed at the hole HL, and is exposed to reaction gas and generated water that is likely to be acidic. As a result, the reinforcing member 20 may be corroded and perforated in the hole HL portion. If there is a hole, a cross leak occurs.

  In the present embodiment, since the reinforcing member 20 is covered with the seal member 40 inside the first seal line, there is no such inconvenience and the occurrence of cross leak can be suppressed.

  Further, in this embodiment, as shown in FIG. 2, the shape of the reinforcing member 20 is adjusted so that a gap NT is formed between the inner end of the reinforcing member 20 and the end face of the anode side diffusion layer 34a. As a result, since the sealing member 40 is in close contact with the electrolyte membrane 32 in the gap NT, it is possible to suppress the leakage of the reaction gas along the electrolyte membrane 32 and to further suppress the cross leak.

  Furthermore, since the inner end portion of the reinforcing member 20 is bonded to the electrolyte membrane 32, the seal integrated member 12 in the present embodiment can suppress deformation in the surface direction of the seal member 40. As a result, the rib RB can be prevented from slipping in the surface direction, so that the sealing performance can be prevented from deteriorating, and gas leakage and cross leakage can be suppressed. Further, since the reinforcing member 20, the electrolyte membrane 32, and the cathode-side porous body 36 b support each other inside the seal member 40, deformation of the seal member 40 is suppressed, and the seal-integrated member 12 of the fuel cell 10 is manufactured when the fuel cell 10 is manufactured. Assembly and handling are improved.

B. Variation:
In the said Example, although the reinforcement member 20 is supported using the electrolyte membrane 32 and the cathode side diffused layer 34b among the members which comprise the laminated member 30, it does not restrict to this but uses other members. Also good. Generally speaking, it is only necessary to support the reinforcing member 20 using at least the end portion of the laminated member 30. The end portion of the laminated member 30 means at least a part of the peripheral portion (outer peripheral portion) in the surface direction of the plate-like member having a predetermined thickness constituting the laminated member 30, and preferably means the entire peripheral portion in the surface direction. To do. The plate-shaped member having a predetermined thickness constituting the laminated member 30 includes, for example, an electrolyte membrane, an anode side diffusion layer, a cathode side diffusion layer, an anode side porous body, and a cathode side porous body. Modification examples in which the reinforcing member 20 is supported using a member different from the embodiment will be described as first to sixth modification examples with reference to FIGS. 12-17 is a figure which respectively shows the structure of the seal integrated member in a 1st-6th modification.

First Modification A first modification will be described with reference to FIG. The seal integrated member 121 in the first modification is different from the electrolyte membrane 32 in the embodiment in the configuration of the electrolyte membrane 320. The electrolyte membrane 320 of the seal integrated member 121 in the first modification is the same size as the anode-side diffusion layer 34a. For this reason, only the cathode side diffusion layer 34b is formed larger than the anode side diffusion layer 34a. The inner end portion of the reinforcing member 20 is bonded to the cathode side diffusion layer 34b, and fixed and supported by the cathode side diffusion layer 34b (FIG. 12: T2).

Second Modification A second modification will be described with reference to FIG. The seal integrated member 122 in the second modification is different from the cathode diffusion layer 34b in the embodiment in the configuration of the cathode diffusion layer 340b. The cathode-side diffusion layer 340b of the seal integrated member 122 in the second modification is the same size as the anode-side diffusion layer 34a. For this reason, only the electrolyte membrane 32 is formed larger than the anode side diffusion layer 34a. The inner end portion of the reinforcing member 20 is bonded to the electrolyte membrane 32. The electrolyte membrane 32 is thin and has low rigidity. However, when the outer end portion of the reinforcing member 20 is fixed with a molding die in the same manner as in the embodiment, the outer end portion and the inner end portion are fixed. Therefore, the reinforcing member 20 can be fixed and supported using the electrolyte membrane 32. (FIG. 13: T2). In this modification, since it can be set as a symmetrical structure to an up-down direction, the moldability at the time of carrying out the injection molding of the sealing member 40 improves.

Third Modification A third modification will be described with reference to FIG. The seal-integrated member 123 in the third modification is different from the anode-side diffusion layer 34a and the cathode-side diffusion layer 34b in the embodiment in the configuration of the anode-side diffusion layer 340a and the cathode-side diffusion layer 340b. The anode side diffusion layer 340a of the seal integrated member 123 in the third modification is the same size as the cathode side diffusion layer 34b in the embodiment. The cathode-side diffusion layer 340b of the seal integrated member 123 in the third modification is the same size as the anode-side diffusion layer 34a in the embodiment. For this reason, the electrolyte membrane 32 and the anode side diffusion layer 340a are formed larger than the cathode side diffusion layer 340b. The inner end portion of the reinforcing member 20 is bonded to the electrolyte membrane 32. The inner end portion of the reinforcing member 20 is bonded to the electrolyte membrane 32, and is fixed and supported by the electrolyte membrane 32 and the anode side diffusion layer 340a (FIG. 14: T2).

-4th modification A 4th modification is demonstrated with reference to FIG. The seal integrated member 124 in the fourth modified example is different from the anode side diffusion layer 34a, the cathode side diffusion layer 34b, and the electrolyte membrane 32 in the embodiment in the configuration of the anode side diffusion layer 340a, the cathode side diffusion layer 340b, and the electrolyte membrane 320. . The anode side diffusion layer 340a of the seal integrated member 124 in the fourth modification is the same size as the cathode side diffusion layer 34b in the embodiment. The cathode-side diffusion layer 340b and the electrolyte membrane 320 of the seal integrated member 123 in the fourth modification are the same size as the anode-side diffusion layer 34a in the embodiment. Therefore, the anode side diffusion layer 340 a is formed larger than the cathode side diffusion layer 340 b and the electrolyte membrane 320. The inner end portion of the reinforcing member 20 is bonded to the anode side diffusion layer 340a and fixed and supported by the anode side diffusion layer 340a (FIG. 15: T2). This modification has a configuration in which the impregnation region of the sealing member 40 in the anode-side diffusion layer 340a is enlarged, and the sealing property on the anode side is more emphasized. In this modification, the possibility that hydrogen leaks from the anode side can be further reduced.

  As in the embodiment, the cathode side diffusion layer 34b is enlarged to increase the impregnation region of the seal member 40 in the cathode side diffusion layer 34b, or the anode side diffusion layer 34a is enlarged to form the cathode as in the fourth modification. Whether to increase the impregnation region of the sealing member 40 in the side diffusion layer 34b is determined in consideration of the design concept, the operating conditions such as the gas pressure of each reaction gas, the adhesion strength of each diffusion layer to the electrolyte membrane, and the like. If the impregnation region on the cathode side is increased, the adhesion strength between the cathode side diffusion layer and the electrolyte membrane and the sealing property on the cathode side can be improved. If the impregnation region on the anode side is increased, the anode side diffusion layer and The adhesion strength with the electrolyte membrane and the sealing performance on the anode side can be improved.

-5th modification A 5th modification is demonstrated with reference to FIG. The seal-integrated member 125 in the fifth modification is different from the anode-side diffusion layer 34a and the electrolyte membrane 32 in the embodiment in the configuration of the anode-side diffusion layer 340a and the electrolyte membrane 320. In the seal integrated member 125 in the fifth modified example, the anode side diffusion layer 340a has the same size as the cathode side diffusion layer 34b in the example, and the electrolyte membrane 320 has the same size as the anode side diffusion layer 34a in the example. Has been. For this reason, the anode side diffusion layer 340 a and the cathode side diffusion layer 34 b are formed larger than the electrolyte membrane 320. The inner end portion of the reinforcing member 20 is sandwiched between the anode side diffusion layer 340a and the cathode side diffusion layer 34b, and fixed and supported by both diffusion layers 340a and 34b (FIG. 16: T2). In this modification, both the anode side diffusion layer 340a and the cathode side diffusion layer 34b can increase the impregnation region of the seal member 40 and improve the sealing performance.

Sixth Modification A sixth modification will be described with reference to FIG. In the seal integrated member 126 in the sixth modification, the configurations of the electrolyte membrane 32, the anode-side diffusion layer 34a, and the cathode-side diffusion layer 340b are the same as those in the second modification. In the seal integrated member 126 according to the sixth modification, the reinforcing member is configured in a two-layer structure including the first layer 20a and the second layer 20b. In the inner end portion of the reinforcing member, the first layer 20a and the second layer 20b sandwich the electrolyte membrane 32. As a result, the present modification has the same operations and effects as the second modification.

-7th modification In the said Example, the laminated member 30 integrated with the sealing member 40 is the electrolyte membrane 32, the anode side diffusion layer 34a, the cathode side diffusion layer 34b, the anode side porous body 36a, and the cathode. Although it is the side porous body 36b, it is not always necessary to integrate all of them. Such an example will be described as a seventh modification with reference to FIG. FIG. 18 is a diagram illustrating a configuration of a seal integrated member according to a seventh modification.

  In the seal integrated member 127 according to the seventh modification, the laminated member 300 integrated with the seal member 40 is the electrolyte membrane 32, the anode side diffusion layer 34a, and the cathode side diffusion layer 34b. The anode-side porous body 36a and the cathode-side porous body 36b are prepared separately, and when the fuel cell 10 is configured by stacking the seal-integrated member 127 and the separator 14, the seal-integrated member 127 and the separator 14 It is arranged between. In this modification, the anode-side porous body 36a and the cathode-side porous body 36b are not formed integrally with the sealing member 40, so that it is not necessary to control the amount of the molding material impregnated in the anode-side porous body 36a and the cathode-side porous body 36b. Therefore, the seal integrated member can be manufactured more easily.

・ Other variations:
In the said Example and modification, although the material of each member of the lamination | stacking member 30 and each member of the separator 14 is specified, it is not limited to these materials, A proper various material can be used. . For example, the anode-side porous body 36a and the cathode-side porous body 36b are formed using a metal porous body, but may be formed using other materials such as a carbon porous body. Moreover, although the separator 14 is formed using a metal, it is also possible to use other materials, such as carbon.

  In the above-described embodiment, the separator 14 has a structure in which three layers of metal plates are laminated, and the portion corresponding to the power generation region has a flat shape. However, the separator 14 may have any other structure. The shape of the separator 14 can be any other shape. Specifically, a separator (for example, made of carbon) in which a groove-like reaction gas flow path is formed on the surface corresponding to the power generation region may be adopted, or the reaction gas may be provided in a portion corresponding to the power generation region. You may employ | adopt the separator (For example, produced by press-molding a metal plate) which has a corrugated plate shape which functions as a flow path.

  Moreover, in the said Example, although the lamination | stacking member 30 is comprised from the electrolyte membrane, the anode side and cathode side diffusion layer, the anode side, and the cathode side porous body, it is not restricted to this. For example, in the case of using a separator in which a reaction gas channel is formed or a separator having a corrugated plate functioning as a reaction gas channel, the anode side and cathode side porous bodies may be omitted.

  As mentioned above, although the Example and modification of this invention were demonstrated, this invention is not limited to these Example and modification at all, and implementation in a various aspect is possible within the range which does not deviate from the summary. It is.

Explanatory drawing which shows the structure of the fuel cell in an Example. Explanatory drawing which shows the structure of the seal integrated member in an Example. Explanatory drawing which shows the flow of the oxidizing gas of a fuel cell. The flowchart which shows the manufacturing step of the seal integrated member in an Example. The front view of MEGA in an Example. The front view of the reinforcement member in an Example. The figure for demonstrating manufacture of the seal integrated member in an Example. The figure which shows the shaping | molding die in an Example. The figure for demonstrating manufacture of the seal integrated member in a comparative example. The figure which shows the shaping | molding die in a comparative example. The figure which shows the structure of the seal integrated member in a comparative example. The figure which shows the structure of the seal integrated member in a 1st modification. The figure which shows the structure of the seal integrated member in a 2nd modification. The figure which shows the structure of the seal integrated member in a 3rd modification. The figure which shows the structure of the seal integrated member in a 4th modification. The figure which shows the structure of the seal integrated member in a 5th modification. The figure which shows the structure of the seal integrated member in a 6th modification. The figure which shows the structure of the seal integrated member in a 7th modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 12 ... Seal integrated member 14 ... Separator 14a ... Cathode plate 14b ... Intermediate plate 14c ... Anode plate 16a-16f ... Manifold hole 20 ... Reinforcement member 30, 300 ... Laminated member 32, 320 ... Electrolyte membrane 34a, 340a ... Anode side diffusion layer 34b, 340b ... Cathode side diffusion layer 35, 350 ... MEGA
36a ... Anode-side porous body 36b ... Cathode-side porous body 40, 400 ... Seal member 120-127 ... Seal integrated member 400 ... Seal member 840 ... Porous body 910 ... Top Type 911 ... Positioning pin 920 ... Lower type

Claims (19)

A seal integrated member constituting a fuel cell by being laminated, the laminate member, and a seal member that is integrated with an end portion of the laminate member and seals between adjacent members when laminated A method for producing a seal integral member,
Preparing the laminated member including at least an electrolyte membrane, a first diffusion layer disposed on one side of the electrolyte membrane, and a second diffusion layer disposed on the other side of the electrolyte membrane;
Preparing a reinforcing member for reinforcing the sealing member from the inside;
Using the end of the laminated member to support the reinforcing member,
The manufacturing method which shape | molds the said sealing member so that the part supported using the said lamination | stacking member among the said reinforcement members may be covered. The manufacturing method according to claim 1,
A part of the end of the laminated member extends outside the other part,
The manufacturing method in which the reinforcing member is supported by being overlapped with the extending portion. In the manufacturing method of Claim 1 or Claim 2,
The reinforcing member is supported by using at least the first diffusion layer of the laminated member. In the manufacturing method in any one of Claims 1 thru | or 3,
The reinforcing member is supported by using at least the first diffusion layer and the second diffusion layer of the laminated member. In the manufacturing method of Claim 3 or Claim 4,
The manufacturing method, wherein the first diffusion layer is an anode side diffusion layer. In the manufacturing method in any one of Claims 1 thru | or 5,
The reinforcing member is supported by at least the electrolyte membrane among the laminated members. In the manufacturing method in any one of Claims 1 thru | or 6,
The manufacturing method in which the reinforcing member is bonded to the laminated member when the reinforcing member is supported. In the manufacturing method in any one of Claim 1 thru | or 7,
In the molding of the seal member, the seal member has a first seal line around a power generation region in the laminated member, and is formed so that the reinforcing member is not exposed inside the first seal line. ,Production method. In the manufacturing method in any one of Claims 1 thru | or 8,
In the molding of the seal member, the seal member has a second seal line around a manifold hole arranged outside the laminated member, and the reinforcing member is not exposed inside the second seal line. The manufacturing method formed as follows. A seal integrated member that is laminated to form a fuel cell,
A laminated member including at least an electrolyte membrane, a first diffusion layer disposed on one side of the electrolyte membrane, and a second diffusion layer disposed on the other side of the electrolyte membrane;
A seal member that seals between adjacent members when laminated, and is integrated with an end of the laminated member;
While being supported using the end of the laminated member, a reinforcing member for reinforcing the seal member from the inside,
With
A portion of the reinforcing member that is supported by at least the laminated member is a seal-integrated member that is covered with the seal member. The seal integrated member according to claim 10,
A part of the end of the laminated member extends outside the other part,
The reinforcing member is a seal-integrated member that is supported by being overlapped with the extending portion. The seal integral member according to claim 10 or 11,
The reinforcing member is a seal-integrated member that is supported using at least the first diffusion layer among the laminated members. The seal integral member according to any one of claims 10 to 12,
The reinforcing member is a seal-integrated member that is supported by using at least the first diffusion layer and the second diffusion layer among the laminated members. The seal integral member according to claim 12 or claim 13,
The seal diffusion member, wherein the first diffusion layer is an anode side diffusion layer. The seal integral member according to any one of claims 10 to 14,
The reinforcing member is a seal-integrated member that is supported by using at least the electrolyte membrane among the laminated members. The seal integral member according to any one of claims 10 to 15,
The reinforcing member is a seal integrated member bonded to the laminated member. The seal integral member according to any one of claims 10 to 16,
The seal member has a first seal line around a power generation region in the laminated member,
A portion of the reinforcing member corresponding to the inside of the first seal line is a seal integrated member covered with the seal member. The seal integral member according to any one of claims 10 to 17,
The seal member and the reinforcing member have a manifold hole arranged outside the laminated member,
The seal member further has a second seal line around the manifold hole, and a portion of the reinforcing member corresponding to the inside of the second seal line is covered with the seal member. , A seal integral member.   A fuel cell comprising a plurality of the seal integrated members according to any one of claims 10 to 18 stacked with a separator interposed therebetween.

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