JP2007188693A - Fuel cell and manufacturing method of fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell performing a positioning of the relative position of a sealing gasket. <P>SOLUTION: A projection part 32 protruding in the thickness direction is provided at the sealing gasket 30 integrated with a power generation unit 20, and a protruded portion 33 and a recessed portion 34 are respectively formed at both both ends of the projection part 32. A through hole with which the projection part 32 is engaged is provided in a separator 40. The power generation unit 20 and the separator 40 in such structure are laminated alternately, and a prescribed tightening force is given, thereby, the projection parts 32 themselves of adjoining sealing gaskets 30 are engaged, and the sealing gasket 30 is positioned. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell in which a plurality of separators and a power generation unit are stacked and a manufacturing method, and more particularly, to a seal gasket that is sandwiched between separators in a stacking process and suppresses fluid leakage in the fuel cell.

  Conventionally, it is a power generation part of a fuel cell, and mainly includes a power generation unit including an electrolyte membrane, an electrode catalyst layer, etc., a separator functioning as a current collector, and interposed between the separators to prevent leakage of fluid inside the fuel cell. 2. Description of the Related Art There is known a fuel cell having a structure in which a plurality of seal gaskets are provided and laminated.

  For example, Patent Document 1 below discloses a structure in which a resin film is bonded to a gasket (seal gasket) forming portion of an electrolyte membrane and a gasket is formed on the resin film. According to such a structure, it is said that the electrolyte membrane and the gasket can be made into an integral structure, and the number of assembling steps can be reduced.

JP 2003-68319 A

  By the way, in such a fuel cell, since the lip portion of the seal line provided in the seal gasket interposed between the separators comes into contact with the separator and exhibits a sealing function, it is necessary to give a predetermined fastening force after stacking. There is.

  However, since the separator and the lip contact each other, it is difficult to position the seal gasket during lamination. For example, when the lip portions are laminated with the relative positions shifted and a fastening force is applied, the lips may fall and the sealing function may deteriorate. In addition, depending on the fastening pressure, the separator could be damaged unexpectedly.

  An object of the present invention is to provide a fuel cell in which the relative position of the seal gasket is positioned in view of the problem that the relative position of the seal gasket may be shifted during lamination.

In order to solve the above problems, the fuel cell of the present invention is configured as follows. That is,
A fuel cell in which a plurality of power generation units and separators are alternately stacked,
Each of the power generation units has a seal gasket that forms a seal line that substantially contacts the separator sandwiching the power generation unit and suppresses leakage of a predetermined fluid flowing in the fuel cell. In preparation for
The seal gasket includes a first engagement portion having a predetermined shape and a second engagement portion that directly engages with the first engagement portion in the seal gasket that is disposed adjacent to the seal gasket. Formed,
The gist of the invention is that the power generation part and the separator are stacked with the seal line positioned by the engagement of the first and second engaging parts of the seal gaskets arranged adjacent to each other.

Moreover, the method for producing the fuel cell of the present invention comprises:
Preparing a power generation unit that generates power using fuel, and separators alternately stacked with the power generation unit;
Provided at the outer peripheral position of the power generation unit is a seal gasket that substantially contacts the separator sandwiching the power generation unit and forms a seal line that suppresses leakage of a predetermined fluid flowing in the fuel cell;
The seal gasket includes a first engagement portion having a predetermined shape, and a second engagement portion that directly engages with the first engagement portion in a seal gasket that is disposed adjacently via the separator. Forming,
The gist of the invention is to stack the power generation unit and the separator while positioning the seal line by the engagement of the first and second engaging portions of the seal gaskets disposed adjacent to each other.

  According to the fuel cell and the method of manufacturing the same of the present invention, the engagement between the first engagement portion formed on the seal gasket and the second engagement portion formed on the seal gasket disposed adjacent to each other via the separator. The power generation unit and the separator are stacked while positioning the seal line. Therefore, it is possible to suppress a positional shift between the seal gaskets, that is, between the seal lines. As a result, a decrease in the sealing performance of the seal line can be suppressed.

  The separator of the fuel cell having the above configuration includes a through hole penetrating in the thickness direction of the separator at the position of the separator corresponding to the first and second engaging portions of the seal gasket, and the through hole The first engagement portion of the seal gasket may be engaged with the second engagement portion of the seal gasket disposed adjacent to the seal gasket.

  According to such a fuel cell, the through hole is formed in the separator stack surface, and the seal line is positioned through the through hole. Therefore, the first and second engaging portions are accommodated inside the fuel cell, and there is no need to greatly change the outer shape of the separator or the like.

  The through hole provided in the separator of the fuel cell having the above-described configuration may be formed in a size that allows the first engagement portion and / or the second engagement portion to be fitted.

  According to such a fuel cell, the relative displacement between the plurality of stacked seal gaskets is suppressed, and the first engagement portion and / or the second engagement portion and the through hole are fitted. By doing so, the position of the separator is also regulated. Therefore, the seal gasket and the separator are appropriately stacked, and the assembly accuracy of the entire fuel cell can be improved.

  A plurality of holes for a manifold through which the predetermined fluid flows are provided for each type of fluid in an outer peripheral portion of the separator of the fuel cell having the above-described configuration. Two engaging portions may be provided as many as the number of the hole portions for the manifold.

  According to such a fuel cell, the seal gasket includes the number of first and second engaging portions corresponding to the number of manifold holes, and each of the plurality of first and second engaging portions is provided. , Engage with the first and second engaging portions of the adjacent seal gaskets. Due to the action of the plurality of first and second engaging portions, it is possible to appropriately suppress the displacement of the positions of the seal gasket and the seal line.

  The through hole of the fuel cell having the above configuration is a manifold hole provided in an outer peripheral portion of the separator through which the predetermined fluid flows, and the seal gasket includes the first engagement portion and / or The first and second engaging portions may be provided at a position where the second engaging portion is accommodated in the manifold hole.

  According to such a fuel cell, since the manifold hole through which a predetermined fluid flows is used as a through hole, it is not necessary to provide special holes for the first and second engaging portions in the separator. Therefore, an existing separator can be used.

  The seal gasket of the fuel cell having the above-described configuration has a communication hole that is alternately stacked with the separator having the manifold hole and forms a part of the manifold, and the seal hole is formed in the communication hole. It is good also as providing the beam part which connects the outer side and inner side of a gasket, and providing the said 1st engaging part and the said 2nd engaging part in the said beam part.

  According to such a fuel cell, the rigidity of the seal gasket and the communication hole is increased by the beam portion formed in the communication hole of the seal gasket. Therefore, deformation of the seal gasket and the communication hole due to the pressure of the predetermined fluid flowing in the manifold can be suppressed.

  The seal gasket of the fuel cell having the above configuration may be formed integrally with the power generation unit.

  According to such a fuel cell, since the seal gasket is integral with the power generation unit, the assembly of the fuel cell can be facilitated. Furthermore, the position shift between the seal gasket and the seal line can be suppressed by the action of the first and second engaging portions, and the entire position shift including the power generation portion can be suppressed.

  The separator of the fuel cell having the above-described configuration may be a three-layer stacked separator having a flat surface by stacking three metal plates.

  According to such a fuel cell, the seal gasket is sandwiched between separators having a flat surface to seal a predetermined fluid from leaking. Since it is clamped by a separator having a flat surface, the position of the seal gasket is easily displaced. By providing such a fuel cell with a mechanism that suppresses a positional shift between the seal gasket and the seal line, the effect of suppressing a decrease in seal performance is great.

  The fuel cell according to another aspect of the present invention is a fuel cell in which a plurality of power generation units and separators are alternately stacked, and each power generation unit substantially contacts the separator sandwiching the power generation unit. A seal gasket that forms a seal line that suppresses leakage of a predetermined fluid flowing in the fuel cell is provided at the outer peripheral position of each power generation unit, and the separator is disposed at an outer peripheral part that is not in contact with the power generation unit. The seal gasket has a through-hole penetrating in the thickness direction, and is a member protruding in the stacking direction, a convex portion protruding in the stacking direction at one end thereof, and a concave portion concave in the stacking direction at the other end, Protruding portions having lengths connected to adjacent seal gaskets are formed through the through-holes of the separator, and the power generation unit and the separator are arranged adjacent to each other. The convex portion of the sealing gasket, is summarized in that stacked by positioning the seal line by the engagement of the concave portion.

  According to the fuel cell of the present invention, the protrusions and the recesses of the stacked protrusions are engaged with each other, so that a plurality of protrusions can be aligned, and the seal gasket and the seal line can be aligned with each other. Position shift can be suppressed. As a result, the seal gasket can be appropriately laminated, and the deterioration of the sealing performance can be suppressed.

Hereinafter, in order to further clarify the operations and effects of the present invention described above, embodiments of the present invention will be described based on examples in the following order.
A. Basic configuration of fuel cell:
B. First embodiment:
C. Second embodiment:
D. Variation:

A. Basic configuration of fuel cell:
FIG. 1 is an explanatory diagram showing a basic configuration of a fuel cell as one embodiment of the present invention. The fuel cell 10 is a solid polymer fuel cell that is supplied with hydrogen gas and air and generates electric power through an electrochemical reaction between hydrogen and oxygen, and is mounted on a vehicle.

  As shown in the figure, the fuel cell 10 includes a power generator 20 having an electrolyte membrane, an electrode catalyst layer, and the like, a separator 40 as a current collector, end plates 85 a and 85 b disposed at both ends of the fuel cell 10, and the like. .

  The fuel cell 10 is formed by alternately laminating a plurality of power generators 20 and separators 40, and interposing terminals 83 and insulators 84 at both ends, respectively, and sandwiching them between two end plates 85a and 85b. That is, a single cell is configured from the power generator 20 and a part of the separator 40 adjacent thereto, and the fuel cell 10 is formed by stacking a plurality of single cells in a stack.

  The end plates 85a and 85b are formed with bolt fastening portions for attaching tension plates (not shown). By using this bolt fastening portion to connect the end plates 85a and 85b with a tension plate, the fuel cell 10 is formed by applying a predetermined fastening force (compression force) in the stacking direction.

  The power generator 20, the separator 40, and the end plate 85a are formed in a substantially rectangular outer shape, and a plurality of holes are provided in the thickness direction along the four sides. By stacking these components, a manifold for hydrogen, air, and cooling water is formed inside the fuel cell 10. Hydrogen gas and air supplied from the outside flow through each manifold inside the fuel cell 10 and are supplied to each power generator 20 without any delay. The hydrogen gas is supplied to the fuel cell 10 by a hydrogen tank (not shown) and the air is supplied by a compressor (not shown).

  Next, the detailed structures of the power generator 20 and the separator 40 will be described. FIG. 2 is a schematic cross-sectional view of the power generation body 20 and the separator 40, and shows the AA cross section of FIG.

  As shown in FIG. 2, the power generation body 20 is integrally formed by surrounding an outer periphery of a member 25 in which gas diffusion layers 23 a and 23 b are arranged outside a MEA 24 (Mebrene Electrode Assembly) including an electrolyte membrane 21 with a seal gasket 30. The porous body channels 26 and 27 are arranged on both sides. In this embodiment, the member 25 composed of the MEA 24 and the gas diffusion layers 23a and 23b corresponds to the power generation unit in the claims. Hereinafter, this is called MEGA25.

  The MEA 24 includes an electrolyte membrane 21 in the approximate center in the thickness direction, and electrode catalyst layers 22a and 22b (cathode and anode) are formed on the surface thereof, respectively. The electrolyte membrane 21 is a thin film of a solid polymer material having proton conductivity, and is formed in a rectangular outer shape smaller than the outer shape of the separator 40. The electrolyte membrane 21 exhibits good electrical conductivity in a wet state. The electrode catalyst layers 22a and 22b formed on the surface of the electrolyte membrane 21 include a catalyst that promotes an electrochemical reaction, such as platinum.

  The gas diffusion layers 23a and 23b disposed outside the MEA 24, specifically, the gas diffusion layer 23a disposed on the cathode side of the MEA 24 and the gas diffusion layer 23b disposed on the anode side are made of carbon porous. For example, it is formed of carbon cloth or carbon paper. The MEA 24 and the gas diffusion layers 23a and 23b made of such materials are integrated by bonding to form the MEGA 25.

  The seal gasket 30 surrounding the outer periphery of the MEGA 25 is made of an insulating resin material made of rubber having elasticity such as silicon rubber, butyl rubber, and fluorine rubber, and is formed by injection molding on the outer periphery of the MEGA 25.

  The outer shape of the seal gasket 30 is formed in the same substantially rectangular shape as the separator 40, and the manifold holes (a plurality of holes provided in the power generation body 20) are formed along the four sides. Yes. That is, the hole of the seal gasket 30 sandwiched between the separators 40 as a part of the power generator 20 constitutes a part of a manifold of fluid (hydrogen, air, cooling water) inside the fuel cell 10. In order to distinguish a manifold hole provided in the seal gasket 30 from a manifold hole provided in the separator 40, the hole of the seal gasket 30 is referred to as a communication hole.

  The seal gasket 30 is formed with a convex portion surrounding each communication hole in the thickness direction. This convex portion is sandwiched between the separators 40, receives a fastening force in the stacking direction, and is crushed and deformed in the stacking direction. As a result, the convex portion forms a seal line SL that suppresses leakage of fluid (hydrogen, air, cooling water) from the manifold. This convex portion becomes the lip portion of the seal line SL.

  In the fuel cell 10 of this embodiment, the fluid leakage from the fuel cell 10 is handled with a configuration in which the seal gasket 30 is sandwiched, and a configuration in which a resin frame or the like is sandwiched between separators is not employed. By doing so, the number of parts such as a resin frame is reduced, and the volume and weight of the fuel cell 10 are reduced.

  The porous body flow paths 26 and 27 that are elements constituting the power generation body 20 are made of a porous body of metal having a large number of pores therein, such as foam metal such as stainless steel, titanium, and a titanium alloy, or a metal mesh. Therefore, it is formed in a substantially rectangular outline smaller than MEGA25. The porous body channels 26 and 27 are formed with a larger porosity than the gas diffusion layers 23a and 23b constituting the MEGA 25, and mainly function as channels for supplying air and hydrogen gas to the MEGA 25.

  For example, the porous channel 26 is disposed between the cathode side of the MEGA 25 (cathode side of the MEA 24) and the separator 40, and supplies air supplied via the manifold and separator 40 to the cathode side of the MEGA 25.

  On the other hand, the porous body flow path 27 is disposed between the anode side of the MEGA 25 (the anode side of the MEA 24) and the separator 40, and supplies hydrogen gas supplied via the manifold and the separator 40 to the anode side of the MEGA 25. . The air or hydrogen gas thus supplied to the MEGA 25 is diffused to the electrode catalyst layers 22a and 22b by the action of the gas diffusion layers 23a and 23b, and reacts via the electrolyte membrane 21. This electrochemical reaction is an exothermic reaction, and cooling water is supplied into the fuel cell 10 in order to operate the fuel cell 10 in a predetermined temperature range.

  Next, the separator 40 which comprises the fuel cell 10 of a present Example is demonstrated. As shown in FIG. 2, the separator 40 is a three-layer stacked separator formed by stacking three metal thin plates. Specifically, the cathode side plate 41 that contacts the porous body channel 26 that is the air channel, the anode side plate 43 that contacts the porous body channel 27 that is the hydrogen gas channel, and both plates And an intermediate plate 42 mainly serving as a cooling water flow path.

  The three plates have a flat surface with no irregularities for the flow path in the thickness direction (that is, the contact surface with the power generation body 20 is flat), and are conductive such as stainless steel, titanium, and titanium alloy. It is made of a metallic material.

  The three plates are formed with holes constituting the above-described various manifolds, and air, hydrogen gas, and cooling water supplied from the outside of the fuel cell 10 flow therethrough. The cathode side plate 41 is formed with a plurality of holes 45 and 46 serving as air inlets and outlets to the porous body flow channel 26 in addition to the manifold holes (see FIG. 1). Similarly, the anode side plate 43 is formed with a plurality of holes (not shown) that serve as inlets and outlets of hydrogen gas to the porous body flow path 27 in addition to the holes for the manifold.

  Of the plurality of manifold holes provided in the intermediate plate 42, the manifold hole through which air flows is formed so as to communicate with the holes 45 and 46 of the cathode side plate 41. The manifold hole through which hydrogen gas flows is formed so as to communicate with the hole of the anode side plate 43. In other words, the hydrogen gas or air manifold and the porous body flow passages 26 and 27 communicate with each other through the intermediate plate 42 and each hole, and a part of the hydrogen gas and air flowing in each manifold is The porous body flow paths 26 and 27 are supplied from the respective holes through the inside of the separator 40 (intermediate plate 42).

  A plurality of notches are formed in the intermediate plate 42 along the long side direction of a substantially rectangular outer shape, and both ends of the notches communicate with the manifold holes through which the cooling water flows. That is, a part of the cooling water flowing in the cooling water manifold of the fuel cell 10 flows inside the separator 40 (intermediate plate 42) to cool the fuel cell 10.

  In the fuel cell 10 according to the present embodiment, which is basically based on the above-described three-layer stacked separator 40 and the power generator 20 integrally provided with the seal gasket 30, which are alternately stacked and given a predetermined fastening force. It has a function of suppressing displacement of the positions of the power generators 20 during assembly. Specifically, the seal gasket 30 is formed with a mechanism that suppresses a positional shift between the seal gaskets 30. Hereinafter, this structure will be described focusing on the seal gasket 30.

B. First embodiment:
FIG. 3 is a plan view showing a part of the fuel cell as the first embodiment. This figure shows a plan view of a part of the fuel cell 10 as viewed from the cathode side plate 41 of the separator 40. A plurality of power generators 20 and separators 40 are alternately stacked from the front side to the back side of the drawing. Yes. 3 indicates a seal line SL including a contact portion with the power generator 20 on the back side of the separator 40 illustrated in the drawing, that is, a lip portion provided on the seal gasket 30.

  As shown in the figure, the separator 40 includes eight manifold holes 47a, 47b, 48a, 48b, 49a, 49b along each side of a substantially rectangular outer shape. Two hole portions 47a provided along one long side constitute an air supply manifold, and two hole portions 47b provided along the other long side constitute an air discharge manifold. To do. Also, the hole 48a provided along one short side constitutes a hydrogen gas supply manifold, and the hole 48b provided along the other short side constitutes a hydrogen gas discharge manifold. To do. Further, the hole 49a provided in parallel with the hole 48b constitutes a manifold for supplying cooling water, and the hole 49b provided in parallel with the hole 48a constitutes a manifold for discharging cooling water. Yes.

  In addition to the eight holes 47a, 47b, 48a, 48b, 49a, 49b constituting such a manifold, the separator 40 is provided with a total of eight elliptical through holes 50. Each through hole 50 is disposed between each hole 47a, 47b, 48a, 48b, 49a, 49b constituting the manifold and at a position not overlapping with the seal line SL. A part of a seal gasket 30 described later is engaged with the through hole 50.

  FIG. 4 shows a schematic cross-sectional view in the vicinity of one through hole 50. This figure shows a BB cross section in FIG. 3 and shows a state in which separators 40 having through holes 50 and power generation bodies 20 are alternately stacked.

  As shown in the figure, the seal gasket 30 is provided with a protruding portion 32 protruding in the thickness direction at a position corresponding to the through hole 50 of the separator 40. The protrusion 32 is made of a rubber insulating resin material that is the same material as the seal gasket 30.

  The protrusion 32 includes a columnar portion 35 that is substantially equivalent to the ellipse of the through hole 50 of the separator 40 and has a cross section that fits into the through hole 50 of the separator 40. One end of the columnar portion 35 is provided with a convex portion 33 formed in a convex shape in the stacking direction, and the other end portion is provided with a concave portion 34 formed in a concave shape in the stacking direction. . That is, the projecting portion 32 includes a columnar portion 35, a convex portion 33, and a concave portion 34.

  The convex portion 33 and the concave portion 34 are formed on a substantially cone having a height in the central axis direction of the columnar portion 35, and the concave portion 34 and the convex portion 33 in the protruding portions 32 of the two adjacent seal gaskets 30 are engaged with each other. It is formed in the size to be.

  The protruding portion 32 is formed such that the length L from the tip of the protruding portion 33 to the bottom of the recessed portion 34 is substantially equal to the sum of the thicknesses of the power generating body 20 and the separator 40 when stacked with a predetermined fastening force. ing. That is, when the lip portion of the seal gasket 30 receives a predetermined fastening force and deforms to form the seal line SL, the fastening force acting between the convex portion 33 and the concave portion 34 of the protruding portion 32 is small, The seal line SL has a structure that does not cause a problem.

  In the present embodiment, the protrusion 32 has a convex portion 33 on one surface of the seal gasket 30 and is provided with a concave portion 34 at the end of the columnar portion 35 protruding from the opposite surface. Yes. More specifically, the relative protrusion of the protrusion 32 in the thickness direction of the seal gasket 30 is set so that the protrusion amount of the separator 40 in the direction of the cathode side plate 41 during stacking is larger than the protrusion amount in the direction of the anode side plate 43. Position is set.

  When the separator 40 having the through hole 50 is stacked on the power generation body 20 having the projecting portion 32, the columnar portion 35 and the recessed portion 34 of the projecting portion 32 extend from the cathode side plate 41 of the separator 40 toward the anode side plate 43. Through the through hole 50, the concave portion 34 protrudes from the surface of the anode side plate 43.

  The next power generator 20 is stacked on the separator 40 in such a state. In other words, the (N + 1) th power generation body 20 is stacked on the separator 40 stacked on the Nth power generation body 20.

  When the (N + 1) th power generation body 20 is stacked on the separator 40 in a state where the concave portion 34 of the protrusion 32 provided in the Nth power generation body 20 protrudes, the convex portion 33 of the (N + 1) th protrusion 32 is formed. , The N-th protruding portion 32 is engaged with the concave portion 34. In this way, a plurality of separators 40 and the power generator 20 are sequentially stacked, and a predetermined fastening force is applied.

  Since the convex portion 33 and the concave portion 34 that are engaged with each other are formed in a substantially conical shape, the central axes of the stacked projecting portions 32 substantially coincide with each other by receiving a predetermined fastening force.

  According to the structure of the fuel cell in the first embodiment described above, it is possible to align the central axes of the stacked projecting portions 32 so that the projecting portions 32 are aligned. As a result, the relative positioning of the lip portion (the convex portion in the thickness direction of the seal gasket) that forms the seal line SL can be performed, and the displacement in the direction orthogonal to the stacking direction between the seal gaskets 30 can be achieved. A suppression mechanism can be constructed. By carrying out like this, it can suppress that a lip part falls by the fastening force, and seal performance falls.

  Further, since the displacement of the position of the lip portion is suppressed, the possibility that a bending stress or the like is generated on the separator 40 due to the displacement of the lip portion can be reduced.

  In the fuel cell in the first embodiment, the protrusion 32 of the seal gasket 30 is fitted into the through hole 50 of the separator 40. That is, the relative displacement between the stacked seal gaskets 30 can be suppressed, and the position of the separator 40 can be restricted, so that the assembly accuracy of the fuel cell 10 as a whole can be improved.

  Furthermore, since the convex portion 33 and the concave portion 34 of the protruding portion 32 are substantially conical, if the concave portion 34 and the convex portion 33 are engaged, the protruding portion gradually protrudes in the process of applying the fastening force. The cores 32 can be aligned with each other. That is, the assembly of the fuel cell 10 can be facilitated.

  Further, in the first embodiment, since the seal gasket 30 and the MEGA 25 have an integral structure, assembly can be facilitated. Furthermore, since the seal gasket 30 and the MEGA 25 have an integral structure, it is possible to suppress the positional shift between the MEGA 25, that is, the entire power generating body 20, as well as the positional shift between the seal gasket 30.

  In this embodiment, the fuel cell 10 is configured by adopting a three-layer stacked separator 40 that is excellent in productivity and has a flat surface. When such a separator 40 is used, the seal line SL is formed only by contact of the lip portion with the surface of the separator 40. By using such a fuel cell 10 with a mechanism that suppresses the positional shift between the seal gaskets 30 of the first embodiment, the effect of suppressing the deterioration of the sealing performance is great.

  In the first embodiment, the seal gasket 30 is provided with a number (eight) of protrusions 32 corresponding to the manifold holes to suppress the relative position shift. If it has the above protrusion part 32, compared with the case where the protrusion part is not provided, there exists an effect in suppression of the shift | offset | difference of the position of the seal gasket 30 between each other. Further, when the number of the projecting portions 32 is two or more, the relative position of the seal line can be defined.

  In the first embodiment, the relative position of the protrusion 32 with respect to the thickness direction of the seal gasket 30 is set so that the protrusion amount in the cathode side plate 41 direction is larger than the protrusion amount in the anode side plate 43 direction. However, it is not limited to this. For example, as shown in FIG. 5A, the protruding portion 32 is formed at a position where the protruding amount D1 toward the cathode side plate 41 and the protruding amount D2 toward the anode side plate 43 are substantially equal. It is also good. Further, as shown in FIG. 5B, the protruding portion 32 may be formed at a position where the protruding amount D1 toward the cathode side plate 41 is smaller than the protruding amount D2 toward the anode side plate 43. .

  As shown in FIG. 5A, in the case of the protruding portion 32 provided with substantially the same protruding amount on both sides around the seal gasket 30, the protruding amount from one surface of the seal gasket 30 is minimized. The moldability of the seal gasket 30 can be improved. In this case, the protrusions 32 of the adjacent seal gaskets 30 engage with each other inside the through hole 50 of the separator 40 to perform centering.

  Further, as shown in FIG. 5B, in the case of the protrusion 32 having a large protrusion amount toward the anode side plate 43, the protrusion 32 extends from the anode side plate 43 of the separator 40 to the cathode side plate 41. The structure penetrates the through hole 50 in the direction. In this case, since the convex part 33 is formed in the edge part of the protrusion part 32 which passes the through-hole 50, the separator 40 and the electric power generation body 20 (seal gasket 30) can be laminated | stacked comparatively easily. In the present embodiment, the through hole 50 has an elliptical shape, but the shape of the through hole is not limited to an ellipse, and may be a circular or irregular shape. In addition, the shape of the seal line can take various shapes such as a circle and an irregular shape in addition to an ellipse, in accordance with the shape of the through hole or regardless of the shape of the through hole.

C. Second embodiment:
FIG. 6 is an explanatory diagram showing a schematic configuration of a fuel cell as a second embodiment. As shown in the figure, the fuel cell 100 of the second embodiment is formed by alternately laminating a three-layer separator 400 and a power generator 200 integrated with a seal gasket, and the seal gasket 300 includes protrusions 320. In this respect, the structure of the fuel cell 10 (first embodiment) shown in FIG. 1 is the same, but the structures of the separator 400 and the power generator 200 are different. Therefore, the structure of the separator 400 and the power generation body 200 will be mainly described, and the other structure is the same as that of the first embodiment, and the description thereof is omitted.

  FIG. 7 is a plan view showing a part of the fuel cell 100 of the second embodiment. This figure shows a plan view of a part of the fuel cell 100 as viewed from the cathode side plate of the separator 400, and a plurality of power generators 200 and separators 400 are alternately laminated from the front side to the back side of the drawing. . 7 indicates a seal line SL including a contact portion with the power generator 200 on the back side of the illustrated separator 400, that is, a lip portion provided on the seal gasket 300.

  As shown in the figure, the separator 400 formed in a substantially rectangular outer shape includes eight manifold holes 47a, 47b, 48a, 48b, 49a, 49b along each side. Each hole is formed at a position and size substantially the same as those of the first embodiment shown in FIG. In order to simplify the description, the same reference numerals as those in the first embodiment are attached to the holes.

  In the separator 400 of the second embodiment, no hole corresponding to the through hole 50 of the first embodiment is provided. Accordingly, the position of the protrusion 320 that suppresses the positional deviation between the seal gaskets 300 is changed, and the protrusion 320 is arranged in each manifold.

  The protrusion 320 disposed in the manifold is formed on a beam 360 provided in the communication hole 47b so as to connect the outside and the inside of the seal gasket 300. That is, in each communication hole of the seal gasket 300 constituting the fuel cell 100 of the second embodiment, there is a beam 360 that connects the outer peripheral side of the seal gasket 300 and the MEGA 25 side. The hole is divided into two. The beam 360 is also made of the same material as that of the seal gasket 300, like the protruding portion 320.

  FIG. 8 is a schematic cross-sectional view of the vicinity of one manifold hole 47a. This figure shows a CC cross section in FIG. 7 and shows a state in which separators 400 and power generation bodies 200 are alternately stacked.

  As shown in the figure, the seal gasket 300 is provided with a protrusion 320 protruding in the thickness direction at a position corresponding to the approximate center of the manifold hole 47a of the separator 400, as in the first embodiment. . The protrusion 320 is composed of a columnar portion 350, a convex portion 330, and a concave portion 340, which is the same as in the first embodiment. However, unlike the first embodiment, the columnar portion 350 has a substantially circular cross-sectional shape and is formed with an outer diameter that fits loosely in the manifold. The convex portion 330 and the concave portion 340 are formed in a substantially conical shape, and the length L from the tip of the convex portion 330 to the bottom of the concave portion 340 is the same as that of the first embodiment, and the power generator during lamination with a predetermined fastening force 20 and the separator 40 are formed to be approximately equal to the sum of the thicknesses.

  The protrusions 320 in the second embodiment are formed with substantially the same amount of protrusion on both sides around the seal gasket 300, and the protrusions of adjacent seal gaskets 300 are formed inside the manifold holes 47 a of the separator 40. The parts 320 engage with each other to perform centering.

  Specifically, when the separator 400 is stacked on the power generation body 200 provided with the protrusion 320, the recessed portion 340 of the protrusion 320 is loosely fitted in the manifold hole 47a. Are stacked, the projecting portion 330 of the projecting portion 320 of the power generator 200 is engaged with the recessed portion 340 of the projecting portion 320 previously stacked. In this way, a plurality of separators 400 and the power generator 200 are sequentially stacked, and a predetermined fastening force is applied.

  Since the convex portion 330 and the concave portion 340 that are engaged with each other are formed in a substantially conical shape, the central axes of the stacked protruding portions 320 substantially coincide with each other by receiving a predetermined fastening force.

  As described above, according to the fuel cell 100 of the second embodiment, as in the first embodiment, the positional shift between the seal gaskets 300 can be suppressed and the sealing performance can be improved. In addition, since a manifold hole is used instead of the through hole 50 of the first embodiment, it is not necessary to provide a special hole for the protrusion 320 in the separator 400. The protrusion 320 is loosely fitted in the manifold hole of the separator 400, and the seal gasket 300 can be positioned without using the separator 400. As a result, the assembly of the fuel cell 100 is relatively easy.

  Furthermore, a beam 360 is formed in the vicinity of the center of each manifold communication hole formed in the seal gasket 300. That is, the MEGA 25 side and the outer peripheral side of the seal line SL surrounding the manifold are connected by the beam 360. Therefore, the rigidity of the seal line SL is increased, and deformation of the seal line SL due to the pressure of the fluid flowing in the manifold can be suppressed.

D. Variation:
In the present embodiment, the protruding portion is made of the same material as the seal gasket and is formed by injection molding. However, at this time, another member for reinforcing the protruding portion may be inserted. For example, the protruding portion may be formed by inserting carbon fiber or the like and impregnating the fiber with resin. By carrying out like this, the rigidity of a projection part can be improved.

  In this embodiment, the seal gasket and the MEGA are integrally formed. However, the seal gasket and the MEGA may be separate members. Even in this case, it is possible to suppress a positional shift between the seal gaskets by providing the seal gasket with the protruding portion.

  In this embodiment, the seal gasket is provided with a projecting portion having a convex portion and a concave portion, and the seal gasket having the same shape is used. The shape of the part does not need to be the same for each seal gasket.

  For example, a seal gasket A (power generation body A) consisting of convex portions at both ends of the projecting portion and a seal gasket B (power generation body B) consisting of concave portions at both ends of the projection portion are prepared, and What is necessary is just to comprise a fuel cell by laminating | stacking the electric power generation body B alternately. Also in this case, the positional shift between the seal gaskets can be suppressed.

  Although various embodiments of the present invention have been described above, the present invention is not limited to such embodiments, and it goes without saying that various configurations can be adopted without departing from the spirit of the present invention. Although the cross section of the protrusion 32 of the first embodiment is an ellipse and the cross section of the protrusion 320 of the second embodiment is a circle, the present invention is not limited to this. For example, it may have a cross-sectional shape such as a square or a triangle.

It is explanatory drawing which shows the basic composition of the fuel cell as one Example of this invention. It is a schematic sectional drawing of a power generation body and a separator. It is a top view which shows a part of fuel cell as 1st Example. It is explanatory drawing which shows typically the schematic cross section of the vicinity of one through-hole. It is explanatory drawing which shows the modification of the protrusion part of 1st Example. It is explanatory drawing which shows schematic structure of the fuel cell as 2nd Example. It is a top view which shows a part of fuel cell of 2nd Example. It is explanatory drawing which shows typically the schematic cross section of the hole part vicinity of one manifold.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 20 ... Electric power generation body 21 ... Electrolyte membrane 22a, 22b ... Electrode catalyst layer 23a, 23b ... Gas diffusion layer 24 ... MEA
25 ... MEGA
26, 27 ... porous body flow path 30 ... seal gasket 32 ... protrusion 33 ... convex part 34 ... concave part 35 ... columnar part 40 ... separator 41 ... cathode side plate 42 ... intermediate plate 43 ... anode side plate 45, 46 ... Hole 47a, 47b, 48a, 48b, 49a, 49b ... Hole 50 ... Through hole 83 ... Terminal 84 ... Insulator 85a, 85b ... End plate 100 ... Fuel cell 200 ... Power generator 300 ... Seal gasket 320 ... Projection 330 ... Convex part 340 ... concave part 350 ... columnar part 400 ... separator

Claims (10)

A fuel cell in which a plurality of power generation units and separators are alternately stacked,
Each of the power generation units has a seal gasket that forms a seal line that substantially contacts the separator sandwiching the power generation unit and suppresses leakage of a predetermined fluid flowing in the fuel cell. In preparation for
The seal gasket includes a first engagement portion having a predetermined shape and a second engagement portion that directly engages with the first engagement portion in the seal gasket that is disposed adjacent to the seal gasket. Formed,
The fuel cell in which the power generation unit and the separator are stacked with the seal line positioned by the engagement of the first and second engagement portions of the adjacently disposed seal gasket. The fuel cell according to claim 1,
The separator includes a through-hole penetrating in the thickness direction of the separator at the position of the separator corresponding to the first and second engaging portions of the seal gasket,
The fuel cell, wherein the first engagement portion of the seal gasket engages with the second engagement portion of the seal gasket disposed adjacent to the seal gasket through the through hole. The fuel cell according to claim 2, wherein
The said through-hole with which the said separator is provided is a fuel cell formed in the magnitude | size which the said 1st engaging part and / or the said 2nd engaging part fit. The fuel cell according to claim 2 or 3, wherein
A plurality of holes for manifold through which the predetermined fluid flows are provided for each type of the fluid in the outer peripheral portion of the separator,
The fuel cell provided with the said through-hole and the said 1st, 2nd engaging part as many as the hole part for said manifolds. The fuel cell according to claim 2, wherein
The through hole is a hole for a manifold through which the predetermined fluid is provided in an outer peripheral portion of the separator,
The seal gasket is provided with the first and second engaging portions at a position where the first engaging portion and / or the second engaging portion is accommodated in the hole for the manifold. . The fuel cell according to claim 5, wherein
The sealing gasket is
The separator having the manifold hole is alternately stacked to form a part of the manifold, and a beam part connecting the outer side and the inner side of the seal gasket is provided in the communication hole. Prepared,
The fuel cell in which the first engaging portion and the second engaging portion are provided in the beam portion. The fuel cell according to any one of claims 1 to 6,
The seal gasket is a fuel cell formed integrally with the power generation unit. The fuel cell according to any one of claims 1 to 7,
The separator is a fuel cell which is a three-layer stacked separator having a flat surface by stacking three metal plates. A fuel cell in which a plurality of power generation units and separators are alternately stacked,
Each of the power generation units has a seal gasket that forms a seal line that substantially contacts the separator sandwiching the power generation unit and suppresses leakage of a predetermined fluid flowing in the fuel cell. In preparation for
The separator has a through-hole that penetrates the separator in the thickness direction at an outer peripheral portion that is not in contact with the power generation unit,
The seal gasket is a member that protrudes in the stacking direction, and has a convex portion that is convex in the stacking direction at one end and a concave portion that is concave in the stacking direction at the other end. And a protrusion having a length to be connected to a seal gasket disposed adjacently is formed,
The fuel cell in which the power generation unit and the separator are stacked by positioning the seal line by engagement of the convex portion and the concave portion of the adjacently disposed seal gasket. A method of manufacturing a fuel cell, comprising:
Preparing a power generation unit that generates power using fuel, and separators alternately stacked with the power generation unit;
Provided at the outer peripheral position of the power generation unit is a seal gasket that substantially contacts the separator sandwiching the power generation unit and forms a seal line that suppresses leakage of a predetermined fluid flowing in the fuel cell;
The seal gasket includes a first engagement portion having a predetermined shape, and a second engagement portion that directly engages with the first engagement portion in a seal gasket that is disposed adjacently via the separator. Forming,
A method of manufacturing a fuel cell, wherein the power generation unit and the separator are stacked while positioning the seal line by the engagement of the first and second engagement portions of the adjacently disposed seal gaskets.

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