阅读说明：本技术 燃料电池用隔板构件以及燃料电池堆 (Separator member for fuel cell and fuel cell stack ) 是由 后藤修平 苫名佑 仪贺章仁 于 2019-07-05 设计创作，主要内容包括：本公开涉及燃料电池用隔板构件以及燃料电池堆。构成燃料电池堆(11)的燃料电池用隔板构件(10)的冷却介质入口桥部(98),从隔板厚度方向俯视观察时,形成与冷却介质入口连通孔(36a)连通的第一连通路(150a)的第一凸部(150)以与第二连通孔凸起部(72e)交叉的方式延伸,形成将第一连通路(150a)与冷却介质流路(76)相互连通的第二连通路(152a)的第二凸部(152)以与第一连通孔凸起部(58e)交叉的方式延伸。(The present disclosure relates to a separator member for a fuel cell and a fuel cell stack. A cooling medium inlet bridge part (98) of a fuel cell separator member (10) constituting a fuel cell stack (11) is configured such that, when viewed in plan from the separator thickness direction, a first convex part (150) forming a first communication passage (150a) communicating with a cooling medium supply passage (36a) extends so as to intersect with a second communication hole protrusion (72e), and a second convex part (152) forming a second communication passage (152a) communicating the first communication passage (150a) with a cooling medium flow field (76) extends so as to intersect with a first communication hole protrusion (58 e).)

1. A fuel cell separator member is provided with a first metal separator (30) and a second metal separator (32) that are stacked on each other, and the fuel cell separator member (10) is formed with:

a coolant flow field (76) provided between the first separator and the second separator;

coolant passages (36a, 36b) penetrating in the thickness direction of the separator; and

a bridge section (98, 100) that connects the coolant flow field and the coolant communication hole to each other,

first protruding seals (58e, 58f) for preventing fluid leakage are formed on the first separator, protruding from the surface (30a) of the first separator in the direction opposite to the second separator so as to surround the coolant communication hole,

second protrusion seals (72e, 72f) for preventing fluid leakage, which protrude from a surface (32a) of the second separator in a direction opposite to the first separator so as to surround the coolant communication hole, are formed on the second separator,

the fuel cell separator member (10) is laminated to an electrolyte membrane electrode assembly (28) and applies a compressive load in the direction of lamination,

the bridge portion has:

a first protrusion (150) that is formed separately from the first boss seal, protrudes from the surface of the first separator in the direction opposite to the second separator, and forms a first communication passage (150a) that communicates with the coolant communication hole; and

a second convex portion (152) that is formed separately from the second bump seal, protrudes from the surface of the second separator in the direction opposite to the first separator, and forms a second communication passage (152a) that communicates the first communication passage and the coolant flow field with each other,

the first projection extends so as to intersect the second convex seal and the second projection extends so as to intersect the first convex seal when viewed from above in the thickness direction of the separator.

2. The separator member for a fuel cell according to claim 1,

the first convex portion and the second convex portion are each set to have a protrusion height such that the first convex portion and the second convex portion receive the compressive load in a load application state in which the compressive load is applied.

3. The separator member for a fuel cell according to claim 2,

the first convex part is provided in plurality in a state of being separated from each other,

the second convex portion is provided in plurality in a state of being separated from each other.

4. The separator member for a fuel cell according to claim 2,

a first inner seal portion (78a) of the first lobe seal, which constitutes an end portion on the cooling medium flow side, is located closer to the cooling medium flow side than a second inner seal portion (80a) of the second lobe seal, which constitutes an end portion on the cooling medium flow side,

the first convex portion intersects the second inner seal portion and the second convex portion intersects the first inner seal portion when viewed in a plan view in a thickness direction of the separator,

a connecting portion (162) between the first communication passage and the second communication passage is located between the first inner seal portion and the second inner seal portion.

5. The separator member for a fuel cell according to claim 1,

a first flat part (82) extending in a planar manner is provided between the coolant communication hole in the first separator and the first boss seal,

a second flat surface portion (84) extending in a planar manner is provided between the coolant communication hole in the second separator and the second boss seal,

the first flat part and the second flat part are in contact with each other.

6. The separator member for a fuel cell according to claim 4,

the disclosed device is provided with: a first pressure receiving portion (164, 176) protruding from a surface of the first partition plate in a direction opposite to the second partition plate; and

a second pressure bearing portion (166, 178) projecting from a surface of the second partition plate in a direction opposite to the first partition plate,

the first pressure-receiving portion is located at a position overlapping the second inner seal portion and the second pressure-receiving portion is located at a position overlapping the first inner seal portion when viewed from the separator thickness direction in plan view,

the first pressure receiving portion and the second pressure receiving portion are each formed so as to receive the compressive load in the load applied state.

7. The separator member for a fuel cell according to claim 1,

the separator is provided with a joint section (47) that joins the outer peripheral section of the first separator plate and the outer peripheral section of the second separator plate to each other.

8. The separator member for a fuel cell according to claim 6,

a first inner protrusion (54) for preventing fluid leakage, which protrudes from the surface of the first separator in a direction opposite to the second separator so as to surround the coolant flow field, is formed on the first separator,

a second inner protrusion (68) for preventing leakage of fluid, which protrudes from the surface of the second separator in a direction opposite to the first separator so as to surround the coolant flow field, is formed on the second separator,

a first inner portion (55) of the first inner protrusion, which is located on the inner side of the first boss seal, is located closer to the cooling medium flow side than a second inner portion (69) of the second inner protrusion, which is located on the inner side of the second boss seal.

9. The separator member for a fuel cell according to claim 8,

the joint is located at a position between the first medial side portion and the second medial side portion.

10. The separator member for a fuel cell according to claim 8,

the first pressure receiving portion is located at a position overlapping the second inner portion, and the second pressure receiving portion is located at a position overlapping the first inner portion, when viewed from the separator thickness direction in plan view.

11. The separator member for a fuel cell according to claim 6,

the first bearing portion includes a plurality of first protrusions (168 a-168 d),

the second pressure receiving portion includes a plurality of second protrusions (172a to 172 d).

12. A fuel cell stack configured by alternately stacking the fuel cell separator member according to any one of claims 1 to 11 and an electrolyte membrane-electrode assembly.

Technical Field

The present disclosure relates to a fuel cell separator member and a fuel cell stack in which a coolant flow field is formed between a first separator and a second separator that are stacked on each other.

Background

For example, a polymer electrolyte fuel cell includes an electrolyte membrane-electrode assembly (MEA) in which an anode electrode is disposed on one surface of an electrolyte membrane formed of a polymer ion exchange membrane and a cathode electrode is disposed on the other surface. The electrolyte membrane-electrode assembly is sandwiched by separators (bipolar plates), thereby constituting a power generation unit cell (unit fuel cell). A fuel cell stack including a stack body in which a predetermined number of power generation cells are stacked is incorporated in, for example, a fuel cell vehicle (a fuel cell electric vehicle or the like).

In some cases, a metal separator is used as the separator in the fuel cell stack. At this time, a seal member is provided to the separator in order to prevent leakage of the reactant gas (oxidant gas, fuel gas) and the cooling medium.

The sealing member has a problem of high cost because it uses an elastic rubber sealing member such as fluorine-based or silicon. Therefore, for example, as disclosed in U.S. Pat. No. 7718293, a structure is adopted in which a convex seal is formed in a partition plate instead of the elastic rubber seal.

Disclosure of Invention

Problems to be solved by the invention

Two separators adjacent to each other in the fuel cell stack are joined to each other so as to form a refrigerant flow path between the separators to constitute a separator member. The separator member has coolant passages formed therethrough in the thickness direction of the separator. The coolant communication hole is surrounded by a convex-shaped convex seal.

The separator is provided with a bridge portion for interconnecting the coolant passages and the coolant flow field. The bridge portion has an inner channel connected to the inner peripheral wall portion of the boss seal and communicating with the coolant communication hole, and an outer channel connected to the outer peripheral wall portion of the boss seal and communicating with the coolant flow field.

In this case, the coupling portion with the inner passage in the inner peripheral wall portion of the boss seal is notched, and the coupling portion with the outer passage in the outer peripheral wall portion of the boss seal is notched. Therefore, the load-resisting property of the joining portion of the convex seal is lowered as compared with the load-resisting property of the other portion (portion other than the joining portion) of the convex seal. It is desirable to suppress occurrence of variation in surface pressure applied to the boss seal (contact pressure at the leading end of the boss seal).

Means for solving the problems

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel cell separator member and a fuel cell stack that can achieve a uniform surface pressure applied to a boss seal surrounding a refrigerant communication hole with a simple and economical structure.

One aspect of the present invention relates to a fuel cell separator member including a first metal separator and a second metal separator stacked on each other, the fuel cell separator member including: a coolant flow field provided between the first separator and the second separator; a coolant communication hole penetrating in the thickness direction of the separator; and a bridge portion that connects the coolant flow field and the coolant communication hole to each other, wherein a first bump seal for preventing fluid leakage that protrudes from a surface of the first separator in a direction opposite to the second separator so as to surround the coolant communication hole is formed in the first separator, and a second bump seal for preventing fluid leakage that protrudes from a surface of the second separator in a direction opposite to the first separator so as to surround the coolant communication hole is formed in the second separator, and wherein the fuel cell separator member is laminated on an electrolyte membrane electrode assembly and applies a compressive load in a laminating direction, wherein the bridge portion includes: a first protrusion formed separately from the first boss seal, protruding from a surface of the first separator in a direction opposite to the second separator, and forming a first communication passage communicating with the coolant communication hole; and a second convex portion that is formed separately from the second bump seal, protrudes from a surface of the second separator in a direction opposite to the first separator, and forms a second communication passage that communicates the first communication passage and the coolant flow field with each other, wherein the first convex portion extends so as to intersect the second bump seal, and the second convex portion extends so as to intersect the first bump seal, when viewed in a plan view in the separator thickness direction.

Another aspect of the present invention relates to a fuel cell stack including a fuel cell separator member including a first metal separator and a second metal separator stacked on each other, and an electrolyte membrane-electrode assembly alternately stacked on each other, wherein the fuel cell separator member includes: a coolant flow field provided between the first separator and the second separator; a coolant communication hole penetrating in the thickness direction of the separator; and a bridge portion that connects the coolant flow field and the coolant communication hole to each other, wherein a first bump seal for preventing fluid leakage that protrudes from a surface of the first separator in a direction opposite to the second separator so as to surround the coolant communication hole is formed in the first separator, and a second bump seal for preventing fluid leakage that protrudes from a surface of the second separator in a direction opposite to the first separator so as to surround the coolant communication hole is formed in the second separator, the fuel cell separator member being stacked on an electrolyte membrane-electrode assembly and applying a compressive load in a stacking direction, the bridge portion including: a first protrusion formed separately from the first boss seal, protruding from a surface of the first separator in a direction opposite to the second separator, and forming a first communication passage communicating with the coolant communication hole; and a second convex portion that is formed separately from the second bump seal, protrudes from a surface of the second separator in a direction opposite to the first separator, and forms a second communication passage that communicates the first communication passage and the coolant flow field with each other, wherein the first convex portion extends so as to intersect the second bump seal, and the second convex portion extends so as to intersect the first bump seal, when viewed in a plan view in the separator thickness direction.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, since the first convex portion and the first boss seal are not coupled, the notch portion is not formed in the first boss seal. Further, since the second projection and the second boss seal are not coupled, the second boss seal does not have a notch portion. Therefore, the load-resisting characteristics of the first and second bump seals are not degraded. Thereby, it is possible to achieve uniformization of the surface pressure applied to the boss seals (the first boss seal and the second boss seal) surrounding the refrigerant communication hole with a simple and economical structure.

The above objects, features and advantages can be easily understood by describing the following embodiments with reference to the accompanying drawings.

Drawings

Fig. 1 is a perspective view illustrating a fuel cell stack according to an embodiment of the present invention.

Fig. 2 is a longitudinal sectional view of a part of the fuel cell stack, with a part omitted.

Fig. 3 is an exploded perspective view of a power generation unit cell constituting a part of the fuel cell stack.

Fig. 4 is a front explanatory view of the fuel cell separator member as viewed from the first separator side.

Fig. 5 is a front explanatory view of the fuel cell separator member as viewed from the second separator side.

Fig. 6 is an explanatory view of a main portion of the first projection seal of the first separator surrounding the coolant supply passage as viewed from the first separator side.

Fig. 7 is a main part explanatory view of a second boss seal of the second separator surrounding the coolant supply passage as viewed from the first separator side.

Fig. 8A is a partially omitted perspective view of the first separator, and fig. 8B is a partially omitted perspective view of the second separator.

Fig. 9 is a sectional view taken along line IX-IX of fig. 6.

Fig. 10 is a cross-sectional view taken along line X-X of fig. 6.

Detailed Description

Hereinafter, a fuel cell separator member and a fuel cell stack according to the present invention will be described by way of preferred embodiments with reference to the accompanying drawings.

As shown in fig. 1 and 2, a fuel cell stack 11 according to an embodiment of the present invention includes a stack 14 in which a plurality of power generation cells 12 are stacked in a horizontal direction (the direction of arrow a). The fuel cell stack 11 is mounted on a fuel cell vehicle such as a fuel cell electric vehicle, not shown.

Terminal plate 16a, insulator 18a, and end plate 20a are disposed in this order outward at one end of laminate 14 in the lamination direction (direction of arrow a). At the other end of the stacked body 14 in the stacking direction, a terminal plate 16b, an insulator 18b, and an end plate 20b are disposed in this order toward the outside.

As shown in fig. 2, the terminal plates 16a and 16b are made of a conductive material, for example, a metal such as copper, aluminum, or stainless steel. Terminal plate 16a has terminal portion 22a extending outward in the stacking direction at substantially the center thereof, and terminal plate 16b has terminal portion 22b extending outward in the stacking direction at substantially the center thereof (see fig. 1).

The insulators 18a and 18b are made of an insulating material, such as Polycarbonate (PC) or phenol resin. A recess 23a that opens toward the stack 14 and accommodates the terminal plate 16a is formed in the center of the insulator 18 a. A recess 23b that opens toward the stack 14 and accommodates the terminal plate 16b is formed in the center of the insulator 18 b.

As shown in fig. 1, the end plates 20a, 20b have a horizontally long (or vertically long) rectangular shape, and a connecting rod 24 is disposed between each side. Both ends of each connecting rod 24 are fixed to the inner surfaces of the end plates 20a, 20b by bolts 26, and a fastening load (compressive load) in the stacking direction (the direction of arrow a) is applied to the plurality of stacked power generation cells 12. The fuel cell stack 11 may be provided with a casing having end plates 20a and 20b as end plates, and the stack 14 may be housed in the casing.

As shown in fig. 2, a membrane electrode assembly 28 (hereinafter, abbreviated as MEA 28) of a power generating unit cell is sandwiched by a first separator 30 and a second separator 32. As shown in fig. 3, at one end of the power generation cell 12 in the direction indicated by the arrow B (horizontal direction in fig. 2), an oxygen-containing gas supply passage 34a, a coolant supply passage (coolant passage) 36a, and a fuel gas discharge passage 38B are provided so as to communicate with each other along the direction indicated by the arrow a.

The oxygen-containing gas supply passage 34a, the coolant supply passage 36a, and the fuel gas discharge passage 38b are arranged in the direction indicated by the arrow C. The oxygen-containing gas supply passage 34a supplies an oxygen-containing gas, for example, an oxygen-containing gas. The coolant supply passage 36a supplies a coolant. The fuel gas discharge passage 38b discharges a fuel gas such as a hydrogen-containing gas.

At the other end of the power generation cell 12 in the direction indicated by the arrow B, a fuel gas supply passage 38a, a coolant discharge passage (coolant passage) 36B, and an oxygen-containing gas discharge passage 34B are provided in the direction indicated by the arrow C, which communicate with each other in the direction indicated by the arrow a.

The fuel gas supply passage 38a supplies the fuel gas. The coolant discharge passage 36b discharges the coolant. The oxygen-containing gas discharge passage 34b discharges the oxygen-containing gas. The arrangement of the oxygen-containing gas supply passage 34a and the oxygen-containing gas discharge passage 34b and the fuel gas supply passage 38a and the fuel gas discharge passage 38b is not limited to this embodiment. Can be set as appropriate according to the required specifications.

As shown in fig. 2, the MEA 28 includes an MEA main body 28a and a resin film 46 provided on the outer peripheral portion of the MEA main body 28 a. The MEA main body 28a has an electrolyte membrane 40, and an anode electrode 42 and a cathode electrode 44 sandwiching the electrolyte membrane 40.

The electrolyte membrane 40 is, for example, a solid polymer electrolyte membrane (cation exchange membrane). The solid polymer electrolyte membrane is, for example, a thin film of perfluorosulfonic acid containing water. The electrolyte membrane 40 is sandwiched by an anode electrode 42 and a cathode electrode 44. The electrolyte membrane 40 can use a HC (hydrocarbon) electrolyte in addition to a fluorine electrolyte. The electrolyte membrane 40 has a smaller planar size (outer dimension) than the anode electrode 42 and the cathode electrode 44.

A frame-shaped resin film 46 is sandwiched between the outer peripheral edge of the anode electrode 42 and the outer peripheral edge of the cathode electrode 44. The inner peripheral end face of the resin film 46 is close to, overlaps with, or abuts against the outer peripheral end face of the electrolyte membrane 40. As shown in fig. 3, the oxygen-containing gas supply passage 34a, the coolant supply passage 36a, and the fuel gas discharge passage 38B are provided at one end of the resin film 46 in the direction indicated by the arrow B. The fuel gas supply passage 38a, the coolant discharge passage 36B, and the oxygen-containing gas discharge passage 34B are provided at the other end of the resin film 46 in the direction indicated by the arrow B.

The resin film 46 is made of, for example, PPS (polyphenylene sulfide), PPA (polyphthalamide), PEN (polyethylene naphthalate), PES (polyethersulfone), LCP (liquid crystal polymer), PVDF (polyvinylidene fluoride), silicone resin, fluorine resin, or m-PPE (modified polyphenylene ether resin), PET (polyethylene terephthalate), PBT (polybutylene terephthalate), or modified polyolefin. Instead of using the resin film 46, the electrolyte membrane 40 may be protruded outward. Further, frame-shaped films may be provided on both sides of the electrolyte membrane 40 protruding outward.

As shown in fig. 2 to 5, the first separator 30 and the second separator 32 are joined to each other to constitute a separator member (a fuel cell separator member) 10. In other words, the separator member 10 is a joined separator including a joining portion 47 joining the outer peripheral portion of the first separator 30 and the outer peripheral portion of the second separator 32 to each other. Examples of a method for joining the first separator 30 and the second separator 32 include laser welding, seam welding, brazing, and caulking.

Each of the first separator 30 and the second separator 32 is made of metal, and is formed by press-forming a cross section of a thin metal plate, which is formed by, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a metal plate having a surface treatment for corrosion prevention applied to a metal surface thereof, into a corrugated shape.

As shown in fig. 2 to 4, for example, an oxidizing gas channel 48 extending in the direction of arrow B is provided on a surface 30a (hereinafter referred to as "surface 30 a") of the first separator 30 facing the MEA 28. As shown in fig. 4, the oxygen-containing gas flow field 48 is fluidly connected to the oxygen-containing gas supply passage 34a and the oxygen-containing gas discharge passage 34 b. The oxidizing gas channel 48 has a linear channel groove 48B between a plurality of projections 48a extending in the direction indicated by the arrow B. Instead of the plurality of linear flow path grooves 48b, a plurality of corrugated flow path grooves may be provided.

An inlet buffer 50A having a plurality of embossed rows formed by a plurality of embossed portions 50A arranged in the direction of the arrow C is provided on the surface 30A of the first separator 30 between the oxygen-containing gas supply passage 34a and the oxygen-containing gas flow field 48. Further, an outlet buffer 50B having a plurality of embossed rows formed by the plurality of embossed portions 50B is provided on the front surface 30a of the first separator 30 between the oxygen-containing gas discharge passage 34B and the oxygen-containing gas flow field 48.

On the surface 30B of the first separator 30 on the side opposite to the oxygen-containing gas flow field 48, an embossed row formed of a plurality of embossed portions 51a arranged in the direction indicated by the arrow C and protruding toward the opposite side is provided between the embossed rows of the inlet buffer 50A, and an embossed row formed of a plurality of embossed portions 51B arranged in the direction indicated by the arrow C and protruding toward the opposite side is provided between the embossed rows of the outlet buffer 50B. The embossed portion 51b constitutes a buffer portion on the refrigerant surface side.

On the surface 30a of the first separator 30, a first seal line (metal convex seal) 52 is formed by press molding so as to project toward the MEA 28 (in the direction opposite to the adjacent second separator 32). The first seal line 52 prevents leakage of fluids (oxidant gas, fuel gas, and cooling medium) from between the first separator 30 and the MEA 28 to the outside. Each side of the first seal line 52 is formed in a straight line shape when viewed from above in the thickness direction of the separator (the direction of arrow a) (hereinafter, simply referred to as "planar view"). In addition, each side of the first seal line 52 may be formed in a wave shape in a plan view.

As shown in fig. 2, the first resin material 60 is fixed to the projection end surface of the first seal line 52 by printing, coating, or the like. For example, polyester fibers are used for the first resin member 60. The first resin member 60 may be provided on the resin film 46 side. The first resin member 60 is not indispensable and may be absent. In a load application state in which a compressive load is applied to the laminated body 14, the first resin member 60 is in gas-tight and liquid-tight contact with the resin film 46.

In fig. 4, the first seal line 52 has a first inner protrusion 54, a first outer protrusion 56, and a plurality of first communication hole protrusions 58a to 58 f.

The first inner protrusion 54 surrounds the oxygen-containing gas channel 48, the inlet buffer 50A, and the outlet buffer 50B. First outer protrusion 56 surrounds the outer peripheral edge of surface 30a of first separator 30 along the inside of joint 47.

The first communication hole boss 58a surrounds the oxidant gas supply communication hole 34 a. The first communication hole projection 58b surrounds the oxidant gas discharge communication hole 34 b. The first communication hole projection 58c surrounds the fuel gas supply communication hole 38 a. The first communication hole projection 58d surrounds the fuel gas discharge communication hole 38 b. The first communication hole protrusion (first boss seal) 58e surrounds the coolant supply communication hole 36 a. The first communication hole protrusion (first boss seal) 58f surrounds the coolant discharge communication hole 36 b.

As shown in fig. 5, a fuel gas flow field 62 extending in the direction of arrow B, for example, is formed on a surface 32a of the second separator 32 facing the MEA 28 (hereinafter referred to as "surface 32 a"). The fuel gas flow field 62 is fluidly connectable to the fuel gas supply passage 38a and the fuel gas discharge passage 38 b. The fuel gas flow field 62 has a straight flow field groove 62B between a plurality of convex portions 62a extending in the direction of arrow B. Instead of the plurality of linear flow grooves 62b, a plurality of corrugated flow grooves may be provided.

An inlet buffer 64A having a plurality of embossed rows formed by a plurality of embossed portions 64A arranged in the direction of the arrow C is provided between the fuel gas supply passage 38a and the fuel gas flow field 62 on the surface 32a of the second separator 32. Further, an outlet buffer 64B having a plurality of embossed rows formed by the plurality of embossed portions 64B is provided between the fuel gas discharge passage 38B and the fuel gas flow field 62 on the surface 32a of the second separator 32.

On the surface 32B of the second separator 32 on the side opposite to the fuel gas flow path 62, an embossed row formed of a plurality of embossed portions 65a arranged in the direction of the arrow C and protruding toward the opposite side is provided between the embossed rows of the inlet buffer 64A, and an embossed row formed of a plurality of embossed portions 65B arranged in the direction of the arrow C and protruding toward the opposite side is provided between the embossed rows of the outlet buffer 64B. The embossed portion 65b constitutes a buffer portion on the refrigerant surface side.

The second seal line 66 is formed by press molding on the surface 32a of the second separator 32 so as to bulge toward the MEA 28 (in the direction opposite to the direction of the adjacent first separator 30). Each side of the second seal line 66 is formed in a straight line shape in a plan view. In addition, each side of the second seal line 66 may be formed in a wavy shape in a plan view.

As shown in fig. 2, the second resin material 74 is fixed to the projection end surface of the second seal line 66 by printing, coating, or the like. The second resin member 74 is made of, for example, polyester fiber. The second resin member 74 may be provided on the resin film 46 side. The second resin member 74 is not indispensable and may be absent.

In fig. 5, the second seal line 66 has a second inner projection 68, a second outer projection 70, and a plurality of second communication hole projections 72a to 72 f.

The second inner protrusion 68 surrounds the fuel gas flow field 62, the inlet buffer 64A, and the outlet buffer 64B. The second outer protrusion 70 surrounds the outer peripheral edge of the surface 32a of the second separator 32 along the inside of the joint 47.

The second communication hole protrusion 72a surrounds the oxidant gas supply communication hole 34 a. The second communication hole protrusion 72b surrounds the oxidant gas discharge communication hole 34 b. The second communication hole protrusion 72c surrounds the fuel gas supply communication hole 38 a. The second communication hole projection 72d surrounds the fuel gas discharge communication hole 38 b. The second communication hole protrusion (second protrusion seal) 72e surrounds the coolant supply communication hole 36 a. The second communication hole protrusion (second boss seal) 72f surrounds the coolant discharge communication hole 36 b.

The second communication hole protrusion 72a is configured similarly to the first communication hole protrusion 58a, and the second communication hole protrusion 72b is configured similarly to the first communication hole protrusion 58 b. The second communication hole protrusion 72c is configured similarly to the first communication hole protrusion 58c, and the second communication hole protrusion 72d is configured similarly to the first communication hole protrusion 58 d.

As shown in fig. 2 and 3, in the separator member 10, the coolant flow field 76 is formed between the first and second metal separators 30, 32 stacked on each other. The coolant flow field 76 is in fluid communication with the coolant supply passage 36a and the coolant discharge passage 36b, which are coolant passages penetrating in the separator thickness direction (the direction of arrow a). The coolant flow field 76 is formed by overlapping the shape of the back surface of the first separator 30 having the oxidant gas flow field 48 with the shape of the back surface of the second separator 32 having the fuel gas flow field 62.

As shown in fig. 6, the first communication hole projection 58e surrounding the coolant supply passage 36a is formed in a square shape in plan view, and includes a first inner seal 78a, a first outer seal 78b, and two first coupling seals 78c and 78 d.

The first inner seal portion 78a constitutes an end portion of the first communication hole boss portion 58e on the cooling medium flow path 76 side and extends in the arrow mark C direction. The first outer seal portion 78b constitutes an end portion of the first communication hole boss portion 58e on the opposite side from the coolant flow field 76 and extends in the arrow mark C direction. The first inner seal portion 78a and the first outer seal portion 78b extend in parallel with each other.

The first connecting seal portion 78c extends in the direction of the arrow B and connects one end of the first inner seal portion 78a and one end of the first outer seal portion 78B to each other. Preferably, in a plan view, a connecting portion (intersection) between the first connecting seal portion 78c and the first inner seal portion 78a and a connecting portion (intersection) between the first connecting seal portion 78c and the first outer seal portion 78b are each formed in a rounded shape (japanese character: R shape). The first connecting seal portion 78d extends in the arrow B direction and connects the other end of the first inner seal portion 78a and the other end of the first outer seal portion 78B to each other. Preferably, in a plan view, a connecting portion (intersection) between the first connecting seal portion 78d and the first inner seal portion 78a and a connecting portion (intersection) between the first connecting seal portion 78d and the first outer seal portion 78b are each formed in a rounded shape.

As shown in fig. 4, the first communication hole projection 58f surrounding the coolant discharge passage 36b is configured in the same manner as the first communication hole projection 58 e. Therefore, a detailed description of the structure of the first communication hole boss portion 58f is omitted. A protruding portion 54a protruding toward the coolant flow field 76 in accordance with the shape of the first communication hole protrusions 58e, 58f is provided at a portion of the first inner protrusion 54 that faces the first communication hole protrusions 58e, 58 f. The protruding portion 54a includes a first inner portion 55 located at a position inside the first communication- hole boss portions 58e, 58 f.

In fig. 7, the second communication hole protrusion 72e of the second separator 32 surrounding the coolant supply communication hole 36a is formed in a rectangular shape in plan view, and includes a second inner seal 80a, a second outer seal 80b, and two second coupling seals 80c and 80 d.

The second coupling seal portion 80c extends in the arrow B direction and couples one end of the second inner seal portion 80a and one end of the second outer seal portion 80B to each other. Preferably, in a plan view, the connecting portion between the second connecting seal portion 80c and the second inner seal portion 80a and the connecting portion between the second connecting seal portion 80c and the second outer seal portion 80b are formed in a rounded shape. The second coupling seal portion 80d extends in the arrow B direction and couples the other end of the second inner seal portion 80a and the other end of the second outer seal portion 80B to each other. Preferably, in a plan view, the connecting portion between the second connecting seal portion 80d and the second inner seal portion 80a and the connecting portion between the second connecting seal portion 80d and the second outer seal portion 80b are formed in a rounded shape.

As shown in fig. 6 and 7, the second communication hole projection 72e is formed to be smaller in size in the arrow mark B direction than the first communication hole projection 58 e. Specifically, the second inner seal 80a is located closer to the coolant supply passage 36a than the first inner seal 78 a. The second inner seal portion 80a does not overlap the first inner seal portion 78a when viewed from above in the thickness direction of the separator. The second outer seal portion 80b and the second coupling seal portions 80c and 80d have overlapping portions that overlap the first outer seal portion 78b and the first coupling seal portions 78c and 78 d. In other words, the entire second outer seal portion 80b overlaps the first outer seal portion 78b, a portion of the second connecting seal portion 80c overlaps the first connecting seal portion 78c, and a portion of the second connecting seal portion 80d overlaps the first connecting seal portion 78 d.

In fig. 5, the second communication hole protrusion 72f surrounding the coolant discharge communication hole 36b is configured similarly to the second communication hole protrusion 72 e. Therefore, detailed description of the structure of the second communication hole protrusion 72f is omitted. As shown in fig. 6 and 7, the first inner portion 55 is located on the coolant flow field 76 side of the second inner portion 69 of the second inner boss 68, and the second inner portion 69 is located on the inner side of the second communication hole bosses 72e and 72 f.

As shown in fig. 4 and 8A, a first flat portion 82 extending in a planar manner is provided between the coolant supply passage 36a and the first passage boss 58e in the first separator 30. In fig. 8A, the first resin material 60 is not shown. As shown in fig. 5 and 8B, a second flat portion 84 extending in a planar manner is provided between the coolant supply passage 36a and the second passage projection 72e in the second separator 32. In fig. 8B, the second resin material 74 is not shown. The first flat portion 82 and the second flat portion 84 are in contact with each other.

In fig. 4, a first flat portion 86 extending in a planar manner is provided between the coolant discharge passage 36b and the first passage hole protrusion 58f in the first separator 30. In fig. 5, a second flat portion 88 extending in a planar manner is provided between the coolant discharge passage 36b and the second passage projection 72f in the second separator 32. The first flat portion 86 and the second flat portion 88 are in contact with each other.

As shown in fig. 4 and 5, the separator member 10 is provided with an oxidizing gas inlet bridge portion 90, an oxidizing gas outlet bridge portion 92, a fuel gas inlet bridge portion 94, a fuel gas outlet bridge portion 96, a cooling medium inlet bridge portion 98, and a cooling medium outlet bridge portion 100.

As shown in fig. 4, the oxygen-containing gas inlet bridge portion 90 connects the oxygen-containing gas supply passage 34a and the oxygen-containing gas flow field 48 to each other. The oxidizing gas inlet bridge portion 90 includes a plurality of first inner passages 102 (see fig. 4) and first outer passages 104 (see fig. 4) formed in the first separator 30, and a plurality of second inner passages 106 (see fig. 5) and second outer passages 108 (see fig. 5) formed in the second separator 32.

In fig. 4, the first inner side passage 102 and the first outer side passage 104 respectively project from the surface 30a of the first separator 30 in the opposite direction to the adjoining second separator 32. The first inner passage 102 extends from the inner peripheral wall portion of the first communication hole protrusion 58a toward the oxidant gas supply communication hole 34 a. The first outer passage 104 extends from the outer peripheral wall portion of the first communication hole boss 58a toward the oxidant gas flow field 48. An opening is provided at an extending end (japanese) of the first outer passage 104, and the oxygen-containing gas supply passage 34a and the oxygen-containing gas flow field 48 are fluidly connected.

In fig. 5, the second inside passage 106 and the second outside passage 108 respectively project from the surface 32a of the second separator 32 in the opposite direction to the adjoining first separator 30. The second inner passage 106 extends from the inner peripheral wall portion of the second communication hole protrusion 72a toward the oxygen-containing gas supply communication hole 34 a. The second outer channel 108 extends from the outer peripheral wall of the second communication hole protrusion 72a toward the oxygen-containing gas flow field 48.

As shown in fig. 4 and 5, the first inner duct 102 and the second inner duct 106 overlap each other in a plan view so as to form one inner passage 110 in communication with each other. The first outer duct 104 and the second outer duct 108 overlap each other in a plan view so as to form one outer passage 112 in communication with each other. The inner passage 110 and the outer passage 112 communicate with each other via an inner hole formed between the first communication hole boss 58a and the second communication hole boss 72 a.

The oxidizing gas outlet bridge 92, the fuel gas inlet bridge 94, and the fuel gas outlet bridge 96 are each configured in the same manner as the oxidizing gas inlet bridge 90. Therefore, the oxidizing gas outlet bridge 92, the fuel gas inlet bridge 94, and the fuel gas outlet bridge 96 will be briefly described, and detailed description thereof will be omitted.

As shown in fig. 4, the oxygen-containing gas outlet bridge portion 92 connects the oxygen-containing gas flow field 48 and the oxygen-containing gas discharge passage 34b to each other. The oxidizing gas outlet bridge portion 92 includes a plurality of first inner passages 114 (see fig. 4) and first outer passages 116 (see fig. 4) formed in the first separator 30, and a plurality of second inner passages 118 (see fig. 5) and second outer passages 120 (see fig. 5) formed in the second separator 32.

In fig. 4 and 5, the first inboard channel 114 and the second inboard channel 118 communicate with each other to form an inboard passage 122. The first outboard channel 116 and the second outboard channel 120 communicate with each other to form an outboard passage 124. The inner passage 122 and the outer passage 124 communicate with each other via an inner hole formed between the first communication hole boss 58b and the second communication hole boss 72 b.

As shown in fig. 5, the fuel gas supply bridge 94 connects the fuel gas supply passage 38a and the fuel gas flow field 62 to each other. The fuel gas inlet bridge portion 94 includes a plurality of first inner passages 126 (see fig. 4) and first outer passages 128 (see fig. 4) formed in the first separator 30, and a plurality of second inner passages 130 (see fig. 5) and second outer passages 132 (see fig. 5) formed in the second separator 32.

In fig. 4 and 5, the first and second inboard channels 126, 130 communicate with each other to form an inboard passageway 134. The first outboard channel 128 and the second outboard channel 132 communicate with each other to form an outboard passage 136. The inner passage 134 and the outer passage 136 communicate with each other via an inner hole formed between the first communication hole boss 58c and the second communication hole boss 72 c.

As shown in fig. 5, the fuel gas outlet bridge portion 96 connects the fuel gas flow field 62 and the fuel gas discharge passage 38b to each other. The fuel gas outlet bridge portion 96 includes a plurality of first inner passages 138 (see fig. 4) and first outer passages 140 (see fig. 4) formed in the first separator 30, and a plurality of second inner passages 142 (see fig. 5) and second outer passages 144 (see fig. 5) formed in the second separator 32.

In fig. 4 and 5, the first and second inboard channels 138, 142 communicate with each other to form an inboard passage 146. The first outboard channel 140 and the second outboard channel 144 communicate with each other to form an outboard passage 148. The inner passage 146 and the outer passage 148 communicate with each other via the inner bores of the first communication hole boss 58d and the second communication hole boss 72 d.

As shown in fig. 6 to 9, the coolant supply bridge 98 connects the coolant supply passage 36a and the coolant flow field 76 to each other. The cooling medium inlet bridge portion 98 includes a plurality of first protrusions 150 formed on the first separator 30 and a plurality of second protrusions 152 formed on the second separator 32.

The number of the first protrusions 150 and the number of the second protrusions 152 are the same as each other. In the present embodiment, although an example is shown in which three first convex portions 150 and three second convex portions 152 are provided, the number of each of the first convex portions 150 and the second convex portions 152 may be one, two, or four or more.

As shown in fig. 6, 8A, and 9, the plurality of first protrusions 150 are formed on the first plane part 82 so as to be separated from the first communication hole protrusions 58 e. The plurality of first protrusions 150 are arranged in parallel with each other in a state of being separated from each other in the arrow C direction (see fig. 6 and 8A). Each first protrusion 150 protrudes from the surface 30a of the first separator 30 (the surface of the first flat surface portion 82) in the direction opposite to the adjacent second separator 32, and forms a first communication passage 150a communicating with the coolant supply passage 36 a.

In fig. 10, the cross-sectional shape of each first convex portion 150 is a trapezoidal shape tapered toward the tip end side. The side walls 154 on both sides of each first projection 150 are inclined with respect to the separator thickness direction (arrow a direction). In a load applied state in which the MEAs 28 and the separator members 10 are alternately stacked and a compressive load is applied in the stacking direction, the projecting end face 156 of the first projecting portion 150 is in surface contact with the MEA 28 (resin film 46) adjacent to the first separator 30. That is, the projection height of each first projection 150 is set so as to receive a compressive load in a load application state in which the compressive load is applied to the stacked body 14.

In the present embodiment, the projecting end surface 156 of the first projection 150 is a flat surface. However, the projecting end surface 156 of the first projecting portion 150 may have a shape other than a flat surface, such as a convex curved surface, if it can be in surface contact with the MEA 28 in a load applied state.

As shown in fig. 6, 8A, and 9, each first projection 150 extends from the opening edge of the coolant supply passage 36a in the direction of arrow B toward the coolant flow field 76. In fig. 6, each first convex portion 150 extends so as to intersect the second inner seal portion 80a and the second inner protrusion portion 68 in a plan view. Thus, each of the first protrusions 150 can receive a reaction force of the surface pressure of the second communication hole protrusion 72e (second inner seal portion 80a) and the second inner protrusion 68 of the second separator 32 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) interposed therebetween (see fig. 9).

That is, the extending end portion of each first projection 150 is located between the first inner seal portion 78a and the second inner seal portion 80a when viewed from the separator thickness direction in plan view. In other words, the extending end (end on the coolant flow field 76 side) of the first projection 150 is positioned closer to the coolant flow field 76 than the second inner protrusion 68 when viewed from the separator thickness direction in plan view. That is, the extended end of the first projection 150 is positioned slightly closer to the coolant supply passage 36a than the first inner seal 78 a.

As shown in fig. 7, 8B, and 9, the plurality of second protrusions 152 are formed between the second hole land 72e and the coolant flow field 76 so as to be separated from the second hole land 72 e. The second protrusions 152 are arranged in parallel with each other in a state of being separated from each other in the arrow C direction (see fig. 7 and 8B). Each second protrusion 152 protrudes from the front surface 32a of the second separator 32 in the direction opposite to the adjacent first separator 30, and forms a second communication passage 152a that communicates the first communication passage 150a and the coolant flow field 76 with each other.

In fig. 10, the cross-sectional shape of each second convex portion 152 is a trapezoidal shape tapered toward the tip side. The side walls 158 on both sides of each second convex portion 152 are inclined with respect to the separator thickness direction (arrow a direction). In a load application state in which a compressive load in the stacking direction is applied to the stacked body 14, the projecting end face 160 of each second projection 152 is in surface contact with the MEA 28 (resin film 46) adjacent to the second separator 32. That is, the projection height of each second convex portion 152 is set so as to receive a compressive load in a load application state in which the compressive load is applied to the stacked body 14.

In the present embodiment, the projecting end surface 160 of the second projecting portion 152 is a flat surface. However, the projecting end surface 160 of the second projecting portion 152 may have a shape other than a flat surface, such as a convex curved surface, if it can be in surface contact with the MEA 28 in a load applied state.

In fig. 7, each second convex portion 152 extends in the arrow B direction so as to intersect the first inner seal portion 78a and the protruding portion 54a of the first inner protrusion 54 in a plan view. Thus, each of the second protrusions 152 can receive a reaction force of the surface pressure of the first communication hole convex portion 58e (first inner seal portion 78a) and the first inner convex portion 54 of the first separator 30 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) interposed therebetween (see fig. 9).

One end (end on the coolant supply passage 36a side) of the second projection 152 overlaps with the extended end of the first projection 150 in a plan view. That is, in a plan view, the coupling portion 162 between the first communication passage 150a and the second communication passage 152a is located between the first inner seal 78a and the second inner seal 80 a. The joint 162 is located at a position between the first inner side portion 55 and the second inner side portion 69. In other words, the coupling portion 162 is located at a position between the second inner side portion 69 and the first inner side seal portion 78 a. The other end portion (end portion on the coolant flow field 76 side) of the second convex portion 152 is positioned closer to the coolant flow field 76 than the protruding portion 54a of the first inner protrusion 54 when viewed in a plan view in the separator thickness direction.

As shown in fig. 6 to 8B, a first pressure receiving portion 164 provided in the first separator 30 and a second pressure receiving portion 166 provided in the second separator 32 are provided in the vicinity of the coolant supply passage 36a in the separator member 10. In fig. 6 and 8A, first pressure receiving portion 164 has a plurality of first protrusions 168A to 168d protruding from surface 30a of first separator 30 (surface of first flat surface portion 82) in a direction opposite to that of adjacent second separator 32. In the load applied state, the projecting end surfaces 170 of the first projections 168a to 168d are in surface contact with the MEA 28 (resin film 46) adjacent to the second separator 32.

In the present embodiment, the projecting end surface 170 of each of the first projections 168a to 168d is an elliptical flat surface. However, the projecting end surfaces 170 of the first projections 168a to 168d may have shapes other than flat surfaces, such as convex curved surfaces, if they can be brought into surface contact with the MEA 28 in a load applied state. The planar shape of the projecting end surface 170 of each of the first projections 168a to 168d is not limited to an elliptical shape, and may be a perfect circle shape or a polygonal shape.

In fig. 6, the first protrusion 168a and the first protrusion 168b are provided so as to overlap the second inner seal portion 80a and sandwich the plurality of first convex portions 150 from the arrow C direction when viewed from the separator thickness direction in plan view. Thus, the first protrusions 168a, 168b can receive the reaction force of the surface pressure of the second communication hole land portion 72e (second inner seal portion 80a) of the second separator 32 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) therebetween. The first protrusion 168a is located at a position between the first coupling seal portion 78c and the first convex portion 150. The first protrusion 168b is located at a position between the first coupling seal portion 78d and the first convex portion 150.

The first protrusions 168C and 168d are provided so as to overlap with the second inner projecting portion 68 (second inner portion 69) and sandwich the plurality of first projecting portions 150 from the arrow C direction when viewed from above in the separator thickness direction. Thus, the first protrusions 168c, 168d can receive the reaction force of the surface pressure of the second inner protrusion 68 of the second separator 32 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) interposed therebetween. The first protrusion 168c is located at a position between the first coupling seal portion 78c and the first convex portion 150. The first protrusion 168d is located at a position between the first coupling sealing part 78d and the first convex part 150.

As shown in fig. 7 and 8B, the second pressure receiving portion 166 has a plurality of second protrusions 172a to 172d protruding from the surface 32a of the second separator 32 in the direction opposite to the adjacent first separator 30. In the load applied state, the projecting end faces 174 of the second projections 172a to 172d are in surface contact with the MEA 28 (resin film 46) adjacent to the first separator 30.

In fig. 7, in the present embodiment, the projecting end surface 174 of each of the second projections 172a to 172d is a substantially L-shaped flat surface. However, the projecting end surfaces 174 of the second projections 172a to 172d may have a shape other than a flat surface, such as a convex curved surface, if they can be brought into surface contact with the anode electrode 42 of the MEA 28 in a loaded state. The planar shape of the projecting end surface 174 of each of the second projections 172a to 172d is not limited to a substantially L shape, and may be a perfect circle shape, an elliptical shape, a square shape, or the like.

In fig. 7, the second protrusions 172a and 172b are provided so as to overlap the first inner seal portion 78a and the first coupling seal portions 78C and 78d and sandwich the plurality of second convex portions 152 from the arrow C direction when viewed from the separator thickness direction in plan view. Thus, the second protrusions 172a, 172b can receive the reaction force of the surface pressure of the first communication hole convex portion 58e of the first separator 30 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) interposed therebetween (see fig. 6). The second projection 172a is located at a position of a connection portion (intersection) of the first inner seal portion 78a and the first connecting seal portion 78 c. The second projection 172b is located at a position of a connection portion (intersection) of the first inner seal portion 78a and the first connecting seal portion 78 d.

The second protrusions 172C and 172d are provided so as to overlap with the corner portions of the protruding portions 54a of the first inner projecting portion 54 and sandwich the plurality of second projecting portions 152 from the arrow C direction when viewed from above in the separator thickness direction. In other words, the second protrusion 172c and the second protrusion 172d are located at positions overlapping the first inner portion 55 when viewed from the separator thickness direction in plan view. Thus, the second protrusions 172c, 172d can receive the reaction force of the surface pressure of the first inner protrusion 54 of the first separator 30 of the separator member 10 disposed adjacently with the MEA 28 (resin film 46) interposed therebetween (see fig. 6).

As shown in fig. 4 and 5, a first pressure receiving portion 176 provided in the first separator 30 and a second pressure receiving portion 178 provided in the second separator 32 are provided in the vicinity of the coolant discharge passage 36b in the separator member 10. The first pressure receiving portion 176 is configured similarly to the first pressure receiving portion 164, and the second pressure receiving portion 178 is configured similarly to the second pressure receiving portion 166. Therefore, a detailed description of the configurations of the first pressure receiving portion 176 and the second pressure receiving portion 178 is omitted.

Next, the operation of the fuel cell stack 11 configured as described above will be described.

First, as shown in fig. 1, an oxygen-containing gas, for example, air, is supplied to the oxygen-containing gas supply passage 34a of the end plate 20 a. A fuel gas such as a hydrogen-containing gas is supplied to the fuel gas supply passage 38a of the end plate 20 a. A coolant such as pure water, ethylene glycol, oil, or the like is supplied to the coolant supply passage 36a of the end plate 20 a.

As shown in fig. 4, the oxygen-containing gas is introduced from the oxygen-containing gas supply passage 34a into the oxygen-containing gas flow field 48 of the first separator 30 via the oxygen-containing gas inlet bridge portion 90. The oxidizing gas then moves along the oxidizing gas channel 48 in the direction indicated by the arrow B and is supplied to the cathode electrode 44 of the MEA main unit 28 a.

On the other hand, as shown in fig. 5, the fuel gas is introduced from the fuel gas supply passage 38a into the fuel gas flow field 62 of the second separator 32 via the fuel gas inlet bridge 94. The fuel gas then moves in the direction indicated by the arrow B along the fuel gas flow field 62, and is supplied to the anode electrode 42 of the MEA main body 28 a.

Therefore, in each MEA main body 28a, the oxidant gas supplied to the cathode electrode 44 and the fuel gas supplied to the anode electrode 42 are consumed by the electrochemical reaction, and power generation is performed.

Then, as shown in fig. 4, the oxygen-containing gas supplied to and consumed by the cathode electrode 44 flows from the oxygen-containing gas flow field 48 to the oxygen-containing gas discharge passage 34b through the oxygen-containing gas outlet bridge portion 92, and is discharged in the direction indicated by the arrow a along the oxygen-containing gas discharge passage 34 b. Similarly, as shown in fig. 5, the fuel gas supplied to and consumed by the anode electrode 42 flows from the fuel gas flow field 62 to the fuel gas discharge passage 38b through the fuel gas outlet bridge portion 96, and is discharged in the direction indicated by the arrow a along the fuel gas discharge passage 38 b.

As shown in fig. 3, the coolant supplied to the coolant supply passage 36a is introduced from the coolant supply passage 36a into the coolant flow field 76 formed between the first separator 30 and the second separator 32 via the coolant inlet bridge 98. At this time, as shown in fig. 9, the coolant flows through the first communication passage 150a of the first protrusion 150 formed in the first separator 30, then flows through the second communication passage 152a of the second protrusion 152 formed in the second separator 32 via the coupling portion 162, and is guided to the coolant flow field 76. The coolant flows through the coolant flow field 76 in the direction indicated by arrow B, thereby cooling the membrane electrode assembly 28.

Subsequently, the coolant flowing through the coolant flow field 76 flows from the coolant flow field 76 to the coolant discharge passage 36b via the coolant outlet bridge 100, and is discharged in the direction of arrow a along the coolant discharge passage 36 b.

In this case, the separator member 10 and the fuel cell stack 11 according to the present embodiment achieve the following effects.

According to the present embodiment, the first convex portion 150 and the first boss seal (the first communication hole convex portions 58e, 58f) are not coupled, and therefore the first boss seal (the first communication hole convex portions 58e, 58f) does not have the notch portion. Further, the second projection 152 is not coupled to the second boss seal (the second communication hole protrusions 72e and 72f), and therefore, no notch portion is formed in the second boss seal (the second communication hole protrusions 72e and 72 f). Therefore, the load-resisting characteristics of the first boss seals (the first communication hole protrusions 58e, 58f) and the second boss seals (the second communication hole protrusions 72e, 72f) are not degraded. This makes it possible to make the surface pressures of the first boss seals (the first communication hole protrusions 58e and 58f) and the second boss seals (the second communication hole protrusions 72e and 72f) surrounding the coolant communication holes (the coolant supply communication hole 36a and the coolant discharge communication hole 36b) uniform with a simple and economical structure.

The first convex portion 150 and the second convex portion 152 are each set to have a protrusion height such that they receive a compressive load in a load application state in which the compressive load is applied.

According to such a configuration, the reaction force of the surface pressure of the first boss seal (the first communication hole boss portions 58e, 58f) can be received by the second protrusion 152, and the reaction force of the surface pressure of the second boss seal (the second communication hole boss portions 72e, 72f) can be received by the first protrusion 150.

The first convex portion 150 is provided in plurality in a state of being separated from each other, and the second convex portion 152 is provided in plurality in a state of being separated from each other.

According to such a configuration, the reaction force of the surface pressure of the first boss seal (the first communication hole boss portions 58e, 58f) can be effectively received by the plurality of second protrusions 152, and the reaction force of the surface pressure of the second boss seal (the second communication hole boss portions 72e, 72f) can be effectively received by the plurality of first protrusions 150.

The first inner seal portion 78a of the first boss seal (the first communication hole boss portions 58e, 58f) constituting the end portion on the coolant flow field 76 side is positioned closer to the coolant flow field 76 side than the second inner seal portion 80a of the second boss seal (the second communication hole boss portions 72e, 72f) constituting the end portion on the coolant flow field 76 side. The first convex portion 150 intersects the second inner seal portion 80a and the second convex portion 152 intersects the first inner seal portion 78a, as viewed from the separator thickness direction plan view. The connection portion 162 between the first communication passage 150a and the second communication passage 152a is located between the first inner seal 78a and the second inner seal 80 a.

With this configuration, the structure of the partition member 10 can be simplified.

First flat portions 82, 86 extending in a planar manner are provided between the coolant passages (coolant supply passages 36a, coolant discharge passages 36b) and the first boss seals (first communication hole bosses 58e, 58f) in the first separator 30. Second flat portions 84, 88 extending in a planar manner are provided between the coolant passages (coolant supply passage 36a, coolant discharge passage 36b) and the second boss seals ( second passage bosses 72e, 72f) in the second separator 32. The first flat portions 82, 86 and the second flat portions 84, 88 are in contact with each other.

With this configuration, the coolant in the coolant passages (coolant supply passage 36a and coolant discharge passage 36b) can be efficiently guided to the first passages 150 a.

The partition member 10 includes first pressure receiving portions 164, 176 protruding from the surface 30a of the first partition plate 30 in the direction opposite to the second partition plate 32; and second pressure receiving portions 166 and 178 projecting from the surface 32a of the second separator 32 in the direction opposite to the first separator 30. When viewed from the separator thickness direction in plan view, the first pressure receiving portions 164 and 176 are located at positions overlapping the second inner seal portion 80a, and the second pressure receiving portions 166 and 178 are located at positions overlapping the first inner seal portion 78 a. The first pressure receiving portions 164 and 176 and the second pressure receiving portions 166 and 178 are formed to receive a compressive load in a load applied state.

With this configuration, the reaction force of the surface pressure of the first boss seal (the first communication hole protrusions 58e and 58f) can be received by the second pressure receiving portion 166, and the reaction force of the surface pressure of the second boss seal (the second communication hole protrusions 72e and 72f) can be received by the first pressure receiving portion 164.

The separator member 10 includes a joint portion 47 that joins the outer peripheral portion of the first separator plate 30 and the outer peripheral portion of the second separator plate 32 to each other.

With this configuration, the first separator 30 and the second separator 32 can be easily integrated.

The fuel cell stack 11 is configured by alternately stacking the separator members 10 and the membrane electrode assemblies 28.

The fuel cell separator member and the fuel cell stack according to the present invention are not limited to the above-described embodiments, and various configurations can be adopted without departing from the scope of the present invention.