JP7565752B2 - Power generating cells and gaskets for polymer electrolyte fuel cells - Google Patents

Description

The present invention relates to a power generating cell for a polymer electrolyte fuel cell and a gasket used therein .

A fuel cell is equipped with a membrane electrode assembly (MEA) that has a pair of electrode layers on both sides of an electrolyte membrane, and separators are laminated on both sides in the thickness direction to form a fuel cell, and a stack structure is formed by stacking multiple fuel cell cells. An oxidizing gas (air) is supplied to the cathode side of the membrane electrode assembly, and a fuel gas (hydrogen) is supplied to the anode side, and electricity is generated by an electrochemical reaction, which is the reverse reaction of the electrolysis of water.

Flow paths are formed within the stacked fuel cell cells for media such as oxidizing gas (air), fuel gas (hydrogen), and cooling water, and a sealing structure is provided to seal each flow path. Gaskets are used in these sealing structures. Gaskets are placed between separators, or between the MEA or electrolyte membrane and a separator, to provide a seal between these two components.

Patent Document 1 discloses a sealing structure in which a gasket made of a rubber material is provided between the separator and the MEA (see paragraphs [0014], [0017], and [Figure 1] of Document 1). In this sealing structure, a gasket groove (5) is formed in the separator (4), and a gasket (6) is fitted into this gasket groove. Ribs (6d) are formed on both sides of the gasket to prevent the gasket from falling out of the gasket groove (see paragraph [0016] of Document 1).

JP 2005-174862 A JP 2006-029364 A

The gasket disclosed in Patent Document 1 is a type of gasket that has a rectangular cross section and is known as a flat gasket (see paragraph [0014] of Patent Document 1), and is less expensive to manufacture than the gasket described in Patent Document 2, which has protruding side projections on both sides of the gasket.

A rubber gasket creates a seal between two components by generating surface pressure due to the reaction force of the rubber when it is crushed. The surface pressure at this time is adjusted so as not to cause deformation of the sealing surface. However, in the case of a flat gasket, the side protrusions (ribs) that prevent the gasket from falling off are also rectangular in shape, so the stress increases at this position, which can cause deformation of the sealing surface. Improvements are required.

The challenge in this case is to prevent the increase in stress at the side protrusion location.

One embodiment of a power generation cell of a polymer electrolyte fuel cell comprises a membrane electrode assembly, a pair of separators sandwiching the membrane electrode assembly, and a gasket fitted into a mounting groove provided in each of the separators and disposed between the membrane electrode assembly and each of the separators, wherein the gasket comprises a gasket body which is an elastic body having a rectangular cross-sectional shape fitted into the mounting groove and brings an end surface into contact with the membrane electrode assembly , and side protrusions which protrude from both side surfaces of the gasket body and contact side walls of the mounting groove in a manner that makes the filling rate in a direction perpendicular to the mounting groove less than 100 percent, and a bottom surface of the mounting groove and a bottom of the gasket are in surface contact with each other through flat surfaces.
One embodiment of the gasket comprises a gasket body which is an elastic body including a rectangular cross-sectional shape that is fitted into a mounting groove provided in one of two components that face each other and has a tip surface that contacts the other of the two components, and side protrusions that protrude from both side surfaces of the gasket body and contact the side walls of the mounting groove in a manner that makes the filling rate in a direction perpendicular to the mounting groove less than 100 percent, and the side protrusions have through holes that penetrate the gasket body in the height direction.

Deformation of the sealing surface at the side protrusion position can be prevented.

FIG. 2 is a schematic diagram showing a cross-sectional side view of a power generating cell. FIG. 2 is a schematic diagram showing a power generating cell in a plan view with the anode-side separator removed. FIG. 13 is a schematic plan view showing a gasket fitted into a mounting groove as a reference example. 4A is a cross-sectional view taken along line AA in FIG. 3, and FIG. 4B is a cross-sectional view taken along line BB in FIG. 5A is a schematic diagram showing a reaction force generated in the region of the gasket shown in FIG. 4A, and FIG. 5B is a schematic diagram showing a reaction force generated in the region of the gasket shown in FIG. 4B. As a first embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 6(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 6(B). As a second embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 7(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 7(B). As a third embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 8(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 8(B). As a fourth embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 9(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 9(B). As a fifth embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 10(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 10(B). As a sixth embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 11(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 11(B). As a seventh embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 12(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 12(B). As an eighth embodiment, (A) is a schematic diagram showing a gasket fitted into an installation groove in a plan view, (B) is a cross-sectional view taken along line A-A in FIG. 13(A), and (C) is a schematic diagram showing the reaction force generated in the area of the gasket shown in FIG. 13(B).

The embodiment will be described with reference to the drawings. This embodiment is a gasket 101 used in a power generation cell 11 that constitutes a fuel cell stack of a polymer electrolyte fuel cell.

(Basic structure)
1 is a schematic diagram of a cross-sectional side view of a power generating cell 11. The power generating cell 11 is a structure that extracts electrical energy from hydrogen and oxygen. To achieve this, the power generating cell 11 has a membrane electrode assembly 31 called an MEA (Membrane Electrode Assembly) sandwiched between a pair of separators 51, and the gap between the membrane electrode assembly 31 and each separator 51 is sealed with a gasket 101.

The membrane electrode assembly 31 has a pair of electrode layers, an anode 33a and a cathode 33b, on both sides of an electrolyte membrane 32 made of a resin film composed of a solid polymer, and these electrode layers are sandwiched between a pair of gas diffusion layers 34.

A pair of separators 51 are provided for each power generation cell 11, and sandwich the membrane electrode assembly 31. Patterned channels (not shown) are provided between one separator 51 and the anode 33a, and between the other separator 51 and the cathode 33b. These channels are constructed by grooves formed in each separator 51.

The power generation cell 11 generates electricity through an electrochemical reaction, which is the reverse reaction of the electrolysis of water, by supplying oxidizing gas (air) to the anode 33a side of the membrane electrode assembly 31 and fuel gas (hydrogen) to the cathode 33b side. The power generation cell 11 uses a channel provided between a pair of separators 51 and the membrane electrode assembly 31 as a flow path (not shown) to guide oxidizing gas (air) to the anode 33a side and fuel gas (hydrogen) to the cathode 33b side. The flow path also includes a path for circulating cooling water.

Figure 2 shows a schematic plan view of the power generation cell 11 with the separator 51 on the anode 33a side removed. Surrounding the membrane electrode assembly 31 is a gasket 101 attached to the separator 51 on the cathode 33b side. The gasket 101 also surrounds the periphery of multiple manifolds 35. The manifolds 35 are structures for directing oxidizing gas (air) to the flow path on the anode 33a side, fuel gas (hydrogen) to the flow path on the cathode 33b side, and cooling water to the flow path for cooling water.

Figure 2 shows a gasket 101 attached to the separator 51 on the cathode 33b side, but another gasket 101 is attached in the same pattern to the separator 51 on the anode 33a side (see Figure 1).

As shown in FIG. 1, the gasket 101 seals between the separator 51 (one of the two components) on the anode 33a side and the anode 33a (the other component). The other gasket 101 seals between the separator 51 (one of the two components) on the cathode 33b side and the cathode 33b (the other component).

A pair of separators 51 each have a mounting groove 52, and a gasket 101 is fitted into each mounting groove 52. The gasket 101 mainly comprises a gasket body 102 that is fitted into the mounting groove 52 and has its tip surface in contact with the anode 33a or cathode 33b, and has multiple side projections 103 on both sides of the gasket body 102. These side projections 103 contact the side walls 52a of the mounting groove 52 with a predetermined surface pressure, preventing the gasket 101 from falling off from the mounting groove 52.

The gasket 101 of this embodiment is a so-called flat gasket, molded from an elastic material such as rubber, with the cross section of the gasket body 102 being rectangular. The height of the gasket 101 in its initial state before compression is set so that it protrudes from the surface of the separator 51. The height of the gasket 101 is set primarily to generate sufficient surface pressure for sealing against the membrane electrode assembly 31, while also taking into consideration the aspect of not increasing the stress too much at the position of the side protrusion 103.

The various embodiments and reference examples of the gasket 101 that will be introduced below are various variations on the side protrusions 103. We will explain the reference examples and their problems, and then explain the first to eighth embodiments.

(Reference example)
A reference example of the gasket 101 will be described with reference to FIGS.

As shown in Figure 3, the gasket 101 of the reference example has side projections 103 arranged symmetrically on the left and right sides of the gasket body 102. As shown in Figures 4(A) and (B), the position where the side projections 103 are not provided (the area of the cross section taken along line A-A in Figure 3) is relatively narrower than the position of the side projections 103 (the area of the cross section taken along line B-B in Figure 3). The position of the side projections 103 is wider than the groove width of the mounting groove 52, and generates surface pressure on the side wall 52a of the mounting groove 52.

Figures 5(A) and (B) show schematic diagrams of the shape of the gasket 101 when it is fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from these drawings, the surface pressure on the separator 51 and membrane electrode assembly 31, which are the objects to be sealed, is greater at the position of the side protrusion 103 shown in Figure 5(B) than at the position where the side protrusion 103 is not provided as shown in Figure 5(A). This is because the gasket 101 has both ends of the side protrusion 103 in contact with the side wall 52a of the fitting groove 52, and therefore has no escape route in the width direction when compressed, resulting in increased stress.

As a result of the increased stress at the position of the side protrusion 103, there is a possibility that the sealing surface of the separator 51 or the membrane electrode assembly 31 may be deformed. The inventor of this embodiment has determined the shape of the side protrusion 103 so that the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent, thereby suppressing the increase in stress at the position of the side protrusion 103. The first to eighth embodiments are introduced below.

(First embodiment)
The first embodiment will be described with reference to Figures 6(A), 6(B), and 6(C). The same parts as those shown in Figures 1 to 5(A) and 5(B) are indicated by the same reference numerals, and the description thereof will be omitted (the same applies to the following embodiments).

The side projections 103 in the first embodiment and the second to fourth embodiments described below are arranged alternately on the left and right at equal intervals along the length of the gasket body 102, thereby making the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 less than 100 percent.

As shown in FIG. 6(A), the side protrusions 103 of this embodiment have a semicircular horizontal cross-sectional shape. Each side protrusion 103 has the same overall height as the gasket body 102, has the same shape, and protrudes in a direction perpendicular to the longitudinal direction of the gasket body 102. Side protrusions 103 of this shape are arranged alternately on the left and right in the longitudinal direction of the gasket body 102 at intervals that prevent the gasket body 102 from falling or meandering.

As shown in FIG. 6(B), at the position of line A-A in FIG. 6(A), the side projection 103 is positioned only on the right half of the gasket body 102. The adjacent side projection 103 is positioned only on the left half of the gasket body 102 (not shown). Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 6(C) shows a schematic diagram of the shape of the region shown in Figure 6(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 6(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

In this embodiment, the side projections 103 are arranged alternately on the left and right, so a rotational moment acts on the gasket body 102. This rotational moment can cause the gasket body 102 to tip or meander due to rotation. Therefore, in this embodiment, we have devised a way to suppress the rotational moment acting on the gasket body 102.

One of the ideas for suppressing the rotational moment is the shape of the side protrusions 103, which protrude in a direction perpendicular to the length of the gasket body 102, that is, perpendicular to the seal line. This suppresses the rotational moment acting on the gasket body 102.

Another way to suppress the rotational moment is to set the spacing between adjacent side protrusions 103. For example, by narrowing the spacing between the side protrusions 103 as much as possible, the rotational moment acting on the gasket body 102 can be suppressed.

Another way to suppress the rotational moment is to set the width of the side protrusion 103. For example, by narrowing the width of the side protrusion 103 to a range that ensures the minimum necessary surface pressure against the side wall 52a of the mounting groove 52, the rotational moment generated in the gasket 101 can be suppressed.

As a result of suppressing the rotational moment acting on the gasket body 102 in this manner, it is possible to prevent the gasket body 102 from falling over or meandering.

The side protrusions 103 in this embodiment have a simple shape, a semicircular horizontal cross section, and have the same overall height as the gasket body 102, each having the same shape, and protruding in a direction perpendicular to the longitudinal direction of the gasket body 102. This makes it easier to manufacture the side protrusions 103.

Second Embodiment
The second embodiment will be described with reference to FIGS.

As shown in FIG. 7(A), the side protrusions 103 of this embodiment have a lip-shaped horizontal cross-sectional shape that protrudes in a direction that is inclined relative to the length direction of the gasket body 102. Each side protrusion 103 has the same overall height as the gasket body 102, and each has the same shape and inclination angle. Side protrusions 103 of this shape are arranged alternately on the left and right in the length direction of the gasket body 102 at intervals that prevent the gasket body 102 from falling or meandering.

As shown in Figure 7(B), at the position of line A-A in Figure 7(A), only the tip of the left side projection 103 is positioned in the left half of the gasket body 102, and only the base of the right side projection 103 is positioned in the right half. Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 7(C) shows a schematic diagram of the shape of the region shown in Figure 7(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 7(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

In this embodiment, the side projections 103 are arranged alternately on the left and right, so a rotational moment acts on the gasket body 102. This rotational moment can cause the gasket body 102 to tip or meander due to rotation. Therefore, in this embodiment, we have devised a way to suppress the rotational moment acting on the gasket body 102.

One way to suppress the rotational moment is to set the spacing between adjacent side protrusions 103. For example, by narrowing the spacing between the side protrusions 103 as much as possible, the rotational moment acting on the gasket body 102 can be suppressed.

Another way to suppress the rotational moment is to set the width of the side protrusion 103. For example, by narrowing the width of the side protrusion 103 to a range that ensures the minimum necessary surface pressure against the side wall 52a of the mounting groove 52, the rotational moment generated in the gasket 101 can be suppressed.

As a result of suppressing the rotational moment acting on the gasket body 102 in this manner, it is possible to prevent the gasket body 102 from falling over or meandering.

The side projections 103 in this embodiment have a simple shape, a lip-shaped horizontal cross section that protrudes in a direction that is inclined relative to the length direction of the gasket body 102, and have the same overall height as the gasket body 102 and the same shape. This makes it possible to easily manufacture the side projections 103.

The side projection 103 in this embodiment has a lip shape that protrudes in a direction that is inclined relative to the longitudinal direction of the gasket body 102. This makes it easier to flex the side projection 103, improving the ease of mounting the gasket 101 in the mounting groove 52.

Third Embodiment
The third embodiment will be described with reference to FIGS.

As shown in FIG. 8(A), the side protrusions 103 of this embodiment have a horizontal cross-sectional shape of an isosceles triangle. Each side protrusion 103 has the same overall height as the gasket body 102, has the same shape, and protrudes in a direction perpendicular to the longitudinal direction of the gasket body 102. Side protrusions 103 of this shape are arranged alternately on the left and right in the longitudinal direction of the gasket body 102 at intervals that prevent the gasket body 102 from falling or meandering.

As shown in FIG. 8(B), at the position of line A-A in FIG. 8(A), the side projection 103 is positioned only on the left half of the gasket body 102. The adjacent side projection 103 is positioned only on the right half of the gasket body 102 (not shown). Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 8(C) shows a schematic diagram of the shape of the region shown in Figure 8(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 8(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

In this embodiment, the side projections 103 are arranged alternately on the left and right, so a rotational moment acts on the gasket body 102. This rotational moment can cause the gasket body 102 to tip or meander due to rotation. Therefore, in this embodiment, we have devised a way to suppress the rotational moment acting on the gasket body 102.

One of the ideas for suppressing the rotational moment is the shape of the side protrusions 103, which protrude in a direction perpendicular to the length of the gasket body 102, that is, perpendicular to the seal line. This suppresses the rotational moment acting on the gasket body 102.

Another way to suppress the rotational moment is to set the spacing between adjacent side protrusions 103. For example, by narrowing the spacing between the side protrusions 103 as much as possible, the rotational moment acting on the gasket body 102 can be suppressed.

Another way to suppress the rotational moment is to set the width of the side protrusion 103. For example, by narrowing the width of the side protrusion 103 to a range that ensures the minimum necessary surface pressure against the side wall 52a of the mounting groove 52, the rotational moment generated in the gasket 101 can be suppressed.

As a result of suppressing the rotational moment acting on the gasket body 102 in this manner, it is possible to prevent the gasket body 102 from falling over or meandering.

The side protrusions 103 in this embodiment have a simple shape, an isosceles triangle in horizontal cross section, and have the same overall height as the gasket body 102, each having the same shape, and protruding in a direction perpendicular to the longitudinal direction of the gasket body 102. This makes it easier to manufacture the side protrusions 103.

(Fourth embodiment)
The fourth embodiment will be described with reference to FIGS.

As shown in FIG. 9(A), the side protrusions 103 of this embodiment have a rectangular horizontal cross-sectional shape on the left side and a semicircular horizontal cross-sectional shape on the right side. Each side protrusion 103 has the same overall height as the gasket body 102 and protrudes in a direction perpendicular to the longitudinal direction of the gasket body 102. Side protrusions 103 of this shape are arranged alternately on the left and right in the longitudinal direction of the gasket body 102 at intervals that do not cause the gasket body 102 to collapse or meander.

As shown in FIG. 9(B), at the position of line A-A in FIG. 9(A), the side projection 103 is positioned only on the right half of the gasket body 102. The adjacent side projection 103 is positioned only on the left half of the gasket body 102 (not shown). Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 9(C) shows a schematic diagram of the shape of the region shown in Figure 9(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 9(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

In this embodiment, the side projections 103 are arranged alternately on the left and right, so a rotational moment acts on the gasket body 102. This rotational moment can cause the gasket body 102 to tip or meander due to rotation. Therefore, in this embodiment, we have devised a way to suppress the rotational moment acting on the gasket body 102.

One of the ideas for suppressing the rotational moment is the shape of the side protrusions 103, which protrude in a direction perpendicular to the length of the gasket body 102, that is, perpendicular to the seal line. This suppresses the rotational moment acting on the gasket body 102.

Another way to suppress the rotational moment is to set the spacing between adjacent side protrusions 103. For example, by narrowing the spacing between the side protrusions 103 as much as possible, the rotational moment acting on the gasket body 102 can be suppressed.

Another way to suppress the rotational moment is to set the width of the side protrusion 103. For example, by narrowing the width of the side protrusion 103 to a range that ensures the minimum necessary surface pressure against the side wall 52a of the mounting groove 52, the rotational moment generated in the gasket 101 can be suppressed.

As a result of suppressing the rotational moment acting on the gasket body 102 in this manner, it is possible to prevent the gasket body 102 from falling over or meandering.

The side protrusions 103 in this embodiment have simple shapes, with a rectangular horizontal cross-sectional shape on the left side in FIG. 9(A) and a semicircular horizontal cross-sectional shape on the right side, and have the same overall height as the gasket body 102, each with the same shape, and protrude in a direction perpendicular to the longitudinal direction of the gasket body 102. This makes it possible to easily manufacture the side protrusions 103.

Fifth embodiment
The fifth embodiment will be described with reference to FIGS.

The side projections 103 in the fifth embodiment and the sixth to eighth embodiments described below are arranged on a line perpendicular to the length of the gasket body 102 and have through holes 104 that penetrate the gasket body 102 in the height direction. The side projections 103 make the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 less than 100 percent.

As shown in FIG. 10(A), the side protrusion 103 of this embodiment has a cylindrical shape with an elliptical ring-shaped horizontal cross section. Therefore, at the position of the side protrusion 103, the continuity of the gasket body 102 is interrupted, and the divided gasket body 102 appears to be connected by the side protrusion 103. The side protrusion 103 has the same overall height as the gasket body 102.

As shown in FIG. 10(B), at the position of line A-A in FIG. 10(A), only both ends of the side projection 103 are positioned across the through hole 104. Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 10(C) shows a schematic diagram of the shape of the region shown in Figure 10(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 10(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

The side projections 103 in this embodiment are arranged symmetrically on a line perpendicular to the longitudinal direction of the gasket body 102. This provides excellent left-right balance and exerts a strong regulating force against the gasket body 102 falling over or meandering. As a result, the width of the side projections 103 can be narrowed to make the seal line thinner. A narrower seal line can further reduce the reaction force against the seal surface, further improving the effect of preventing deformation of the seal surface.

The side protrusions 103 in this embodiment have the same overall height as the gasket body 102, which makes it easier to manufacture the side protrusions 103.

Sixth embodiment
The sixth embodiment will be described with reference to FIGS.

As shown in FIG. 11(A), the side projection 103 of this embodiment has a semicircular horizontal cross-sectional shape that is symmetrical on the left and right, and through holes 104 are provided symmetrically on both sides of the gasket body 102. The through holes 104 also have a semicircular horizontal cross-sectional shape that conforms to the side projection 103. The side projection 103 has the same overall height as the gasket body 102.

As shown in FIG. 11(B), at the position of line A-A in FIG. 11(A), the through holes 104 are positioned on both sides of the gasket body 102. Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 11(C) shows a schematic diagram of the shape of the region shown in Figure 11(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 11(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

The side projections 103 in this embodiment are arranged symmetrically on a line perpendicular to the longitudinal direction of the gasket body 102. This provides excellent left-right balance and exerts a strong regulating force against the gasket body 102 falling over or meandering. As a result, the width of the side projections 103 can be narrowed to make the seal line thinner. A narrower seal line can further reduce the reaction force against the seal surface, further improving the effect of preventing deformation of the seal surface.

The side protrusions 103 in this embodiment have the same overall height as the gasket body 102, which makes it easier to manufacture the side protrusions 103.

Seventh embodiment
The seventh embodiment will be described with reference to FIGS.

As shown in FIG. 12(A), the side protrusion 103 of this embodiment has a horizontal cross-sectional shape of an isosceles triangle that is symmetrical, and through holes 104 are provided symmetrically on both sides of the gasket body 102. The through holes 104 also have a horizontal cross-sectional shape of an isosceles triangle that conforms to the side protrusion 103. The side protrusion 103 has the same overall height as the gasket body 102.

As shown in FIG. 12(B), at the position of line A-A in FIG. 12(A), the through holes 104 are positioned on both sides of the gasket body 102. Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 12(C) shows a schematic diagram of the shape of the region shown in Figure 12(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 12(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

The side projections 103 in this embodiment are arranged symmetrically on a line perpendicular to the longitudinal direction of the gasket body 102. This provides excellent left-right balance and exerts a strong regulating force against the gasket body 102 falling over or meandering. As a result, the width of the side projections 103 can be narrowed to make the seal line thinner. A narrower seal line can further reduce the reaction force against the seal surface, further improving the effect of preventing deformation of the seal surface.

The side protrusions 103 in this embodiment have the same overall height as the gasket body 102, which makes it easier to manufacture the side protrusions 103.

Eighth embodiment
The eighth embodiment will be described with reference to FIGS.

As shown in FIG. 13(A), the side projection 103 of this embodiment has a trapezoidal horizontal cross-sectional shape that is symmetrical on the left and right, and through holes 104 are provided symmetrically on both sides of the gasket body 102. The through holes 104 also have a trapezoidal horizontal cross-sectional shape that conforms to the side projection 103. The side projection 103 has the same overall height as the gasket body 102.

As shown in FIG. 13(B), at the position of line A-A in FIG. 13(A), the through holes 104 are positioned on both sides of the gasket body 102. Therefore, the filling rate of the gasket 101 in the direction perpendicular to the mounting groove 52 is less than 100 percent.

Figure 13(C) shows a schematic diagram of the shape of the region shown in Figure 13(B) of the gasket 101 that has been fitted and crushed to form the power generation cell 11, together with the surface pressure (white arrow). As is clear from Figure 13(C), compared to the gasket 101 shown in Figure 5(B) in which the filling rate in the direction perpendicular to the fitting groove 52 is 100%, the gasket 101 of this embodiment has a smaller surface pressure against the object to be sealed. As a result, the separator 51 and the membrane electrode assembly 31 can be protected from deformation due to increased surface pressure at the position of the side protrusion 103, and deformation of the sealing surface can be prevented.

The side projections 103 in this embodiment are arranged symmetrically on a line perpendicular to the longitudinal direction of the gasket body 102. This provides excellent left-right balance and exerts a strong regulating force against the gasket body 102 falling over or meandering. As a result, the width of the side projections 103 can be narrowed to make the seal line thinner. A narrower seal line can further reduce the reaction force against the seal surface, further improving the effect of preventing deformation of the seal surface.

The side protrusions 103 in this embodiment have the same overall height as the gasket body 102, which makes it easier to manufacture the side protrusions 103.

(Modification)
Various modifications and variations are permitted when implementing the present invention.

For example, the gasket body 102 does not necessarily have to have a rectangular cross-sectional shape, but may have a rectangular cross-sectional shape. A gasket body 102 having a rectangular cross-sectional shape includes, for example, a gasket body having a mountain-shaped lip on the tip surface.

The object to be sealed by the gasket 101 does not necessarily have to be a component such as the membrane electrode assembly 31 or separator 51 of a fuel cell, but can be applied to any other object to be sealed.

In the above embodiment, the side protrusions 103 have the same overall height as the gasket body 102, but this is not limited to this in practice, and the invention can also be applied to side protrusions 103 that are shorter in height than the gasket body 102.

All other variations and modifications are permitted.

Reference Signs List 11 Power generating cell 31 Membrane electrode assembly 32 Electrolyte membrane 33a Anode 33b Cathode 34 Gas diffusion layer 35 Manifold 51 Separator 52 Mounting groove 52a Side wall 101 Gasket 102 Gasket body 103 Side projection 104 Through hole

Claims (9)

A membrane electrode assembly;
A pair of separators sandwiching the membrane electrode assembly;
a gasket that is fitted into a mounting groove provided in each of the separators and disposed between the membrane electrode assembly and each of the separators;
Equipped with
The gasket includes a gasket body that is an elastic body having a rectangular cross-sectional shape and is fitted into the mounting groove and has a tip surface that contacts the membrane electrode assembly ;
side protrusions protruding from both side surfaces of the gasket body and contacting the side walls of the mounting groove in a manner that makes the filling rate in a direction perpendicular to the mounting groove less than 100 percent;
Equipped with
The bottom surface of the mounting groove and the bottom of the gasket are in surface contact with each other through flat surfaces.
A power generation cell of a polymer electrolyte fuel cell . The side projections have the same overall height as the gasket body.
A power generating cell of a polymer electrolyte fuel cell according to claim 1 . The side protrusions are arranged alternately on the left and right at equal intervals in the longitudinal direction of the gasket body.
A power generating cell of a polymer electrolyte fuel cell according to claim 1 or 2. The left and right side protrusions have the same shape.
A power generating cell of a polymer electrolyte fuel cell according to claim 3. The side protrusion protrudes in a direction perpendicular to the longitudinal direction of the gasket body.
A power generating cell of a polymer electrolyte fuel cell according to claim 3. The side protrusions protrude in a direction inclined with respect to the longitudinal direction of the gasket body.
A power generating cell of a polymer electrolyte fuel cell according to claim 3. A gasket body is an elastic body having a rectangular cross-sectional shape, the gasket body being fitted into a mounting groove provided in one of two members facing each other and bringing a tip surface into contact with the other one of the two members;
side protrusions protruding from both side surfaces of the gasket body and contacting the side walls of the mounting groove in a manner that makes the filling rate in a direction perpendicular to the mounting groove less than 100 percent;
Equipped with
The side protrusion has a through hole penetrating the gasket body in the height direction.
gasket . The side projections have the same overall height as the gasket body.
8. The gasket of claim 7. The side protrusions are arranged on a line perpendicular to the longitudinal direction of the gasket body.
9. The gasket according to claim 7 or 8 .

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