JP2022090256A - Laminate structure, and solid polymer water electrolysis cell - Google Patents

Abstract

To provide a technique that improves the sealability of a manifold formed inside a laminate structure.SOLUTION: The laminate structure comprises a pair of laminated members laminated in such a manner that the main faces thereof face each other, with the main face being formed with a manifold for a fluid to flow therethrough, a seal member disposed between the pair of members, groove parts formed on the main face of each of the pair of members in a manner of surrounding the manifold, and a plurality of protrusions formed on the manifold of the pair of members to protrude in the laminating direction of the pair of members. The protrusions formed on one of the pair of members are arranged on the positions overlapping the groove parts formed on the other of the pair of members in the extending direction of the groove parts in the laminating direction, and configured to enable a fluid to flow through between the neighboring protrusions in a state in which the seal member is placed between the groove parts formed on the other of the pair of members and themselves.SELECTED DRAWING: Figure 10

Description

The present invention relates to a laminated structure and a polymer electrolyte water electrolysis cell.

Conventionally, a laminated structure formed by laminating a plurality of members is known. When this laminated structure is a cell constituting a polymer electrolyte fuel cell or a solid electrolyte battery, a manifold portion through which a fluid flows is formed inside the cell, and a seal member is arranged between the members. , It is necessary to maintain the sealing property of the manifold portion (for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2016-131085 Japanese Unexamined Patent Application Publication No. 2003-166092

However, even in the above-mentioned prior art, there is still room for improvement in order to improve the sealing property of the manifold portion in the laminated structure.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a technique for improving the sealing property of a manifold portion formed inside a laminated structure.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms.

(1) According to one embodiment of the present invention, a laminated structure is provided. This laminated structure is a pair of members to be laminated, and the main surfaces of the members are laminated so as to face each other, and a manifold portion through which a fluid flows is formed on the main surface. A seal member arranged between the pair of members, a groove formed so as to surround the manifold portion on the main surface of the pair of members, and the manifold portion formed of the pair of members. A plurality of protrusions projecting in the stacking direction of the members, and the plurality of protrusions formed on one of the pair of members are formed on the other of the pair of members in the stacking direction. The protrusions adjacent to each other in a state where the seal member is arranged at a position overlapping the groove portion along the extending direction of the groove portion and the seal member is arranged between the groove portion formed on the other side of the pair of members. The fluid is configured to be able to flow between the parts.

According to this configuration, each of the pair of members has a groove formed so as to surround the manifold portion. When the pair of members and the seal member are laminated, the surface of the seal member is deformed and protrudes toward the inside of the groove portion, so that the sealability of the manifold portion by the seal member is maintained. A plurality of manifold portions formed on one of the pair of members are arranged along the extending direction of the other groove portion of the pair of members at a position overlapping the groove portion formed on the other side of the pair of members in the stacking direction. A protrusion is provided. As a result, in one of the pair of members, the total thickness of the manifold portion and the protrusion portion becomes a value close to the thickness of the portion where the manifold portion is not formed at the position where the other groove portions of the pair of members overlap. That is, since the laminated structure has a small gap at the position where it overlaps with the groove portion in the laminated direction, the structural strength in the laminated direction can be increased. Thereby, at the position overlapping with the groove portion in the stacking direction, the seal member or the member laminated on the pair of members can be supported so that the surface is easily deformed toward the inside of the groove portion. Further, the plurality of protrusions are configured such that a gap through which a fluid can flow is formed between adjacent protrusions in the manifold portion. As a result, the flow of the fluid in the manifold portion is less likely to be obstructed by the plurality of protrusions. Therefore, it is possible to improve the sealing property of the manifold portion by the sealing member while circulating the fluid in the manifold portion.

(2) In the laminated structure of the above-described structure, the tops of the plurality of protrusions formed on one of the pair of members are formed in the extending direction of the groove formed on the other of the pair of members. Grooves extending along the direction may be formed. According to this configuration, a groove extending in a direction along the extending direction of the groove formed on the other side of the pair of members is formed on the top of the protrusion. As a result, the surface of the seal member facing the top of the protrusion is deformed toward the inside of the groove formed in the top, and the sealing property between the seal member and the protrusion can be maintained. Therefore, in the manifold portion, the fluid can be prevented from flowing between the seal member and the protrusion, so that the fluid can flow between the protrusions adjacent to each other.

(3) In the laminated structure of the above embodiment, the pair of members are formed on the outside of the manifold portion of the main surface and include an outer peripheral portion having the groove portion, and the manifold portion is the main surface. The surface may be recessed with respect to the outer peripheral portion, and the protrusion may be formed so that the height of the apex is aligned with the height of the outer peripheral portion. According to this configuration, the protrusion is formed so that the height of the top is aligned with the height of the outer peripheral portion having the groove. As a result, in one of the pair of members, the total thickness of the manifold portion and the protrusion portion is almost the same as the thickness of the portion where the manifold portion is not formed, so that the seal member is more easily deformed. Therefore, the sealing property of the manifold portion by the sealing member can be further improved.

(4) In the laminated structure of the above embodiment, the manifold portion includes a recess recessed with respect to the outer peripheral portion and a hole portion adjacent to the recess, and the pair of members is the recess. It is formed in a long shape along the boundary between the recess and the hole, and the flow direction of the fluid from the recess to the hole is switched from the direction along the recess to the direction intersecting the direction along the recess. It may be provided with a long portion. According to this configuration, the pair of members are formed in a long shape along the boundary between the recess and the hole in the manifold portion, and the flow direction of the fluid from the recess to the hole is changed from the direction along the recess. It is provided with a long portion that switches in a direction that intersects with a direction along the recess. As a result, a through hole is formed in the seal member to communicate the manifold portions of the pair of members. When the recess is arranged in the seal member in each of the pair of members, the pair of members has the seal member in the recess. The fluid can be easily exchanged between the manifold portions of the pair of members through the through holes of the seal member while being held by the long portion.

(5) In the laminated structure of the above-described embodiment, both ends of the long portion are connected to the outer peripheral portion in the hole portion, and a plurality of protrusions protruding from the outer peripheral portion in the stacking direction are formed. It may be formed. According to this configuration, a plurality of protrusions protruding from the outer peripheral portion in the stacking direction are formed in the elongated portion. As a result, the plurality of protrusions can come into contact with the members adjacent to the pair of members, so that it is possible to suppress the depression of the members into the holes. Therefore, it is possible to suppress a decrease in the cross-sectional area of the hole.

(6) According to another embodiment of the present invention, a polymer electrolyte water electrolysis cell is provided. This solid polymer electrolyzed cell includes the above-mentioned laminated structure, and one of the pair of members is an anode side spacer and the other is a cathode side spacer. According to this configuration, in the laminated structure included in the solid polymer electrolyzed cell, one of the pair of members is used as an anode side spacer and the other is used as a cathode side spacer. In the solid polymer type water electrolysis cell, oxygen gas and hydrogen ions are generated by supplying water to the anode side spacer, and at the cathode side spacer, a membrane electrode assembly between the anode side spacer and the cathode side spacer is formed. Hydrogen is generated from the hydrogen ion supplied through the hydrogen ion. By providing the above-mentioned laminated structure in this solid polymer type water electrolysis cell, it is possible to prevent water flowing through the manifold portion of the anode side spacer and hydrogen gas flowing through the manifold portion of the cathode side spacer from leaking to the outside. can.

The present invention can be realized in various aspects, for example, in various forms such as various devices including a laminated structure, a method for manufacturing a laminated structure, a control method for a device including the laminated structure, and the like. can do.

It is a schematic diagram of the water electrolysis cell of 1st Embodiment. It is a schematic diagram of the water electrolysis apparatus provided with a plurality of water electrolysis cells. It is a perspective view of the anode side spacer. It is the figure which looked at the anode side spacer from the bipolar plate side. It is the figure which looked at the anode side spacer from the membrane electrode joint side. FIG. 3 is an enlarged view of part A in FIG. It is the figure which looked at the cathode side spacer from the membrane electrode joint side. It is the figure which looked at the cathode side spacer from the bipolar plate side. It is 1st schematic diagram explaining the operation of the water electrolysis cell of 1st Embodiment. It is a transmission enlarged view of the water electrolysis cell of 1st Embodiment. It is a transmission enlarged view of the water electrolysis cell of the comparative example. It is a 2nd schematic diagram explaining the operation of the water electrolysis cell of 1st Embodiment. It is a 1st partial cross-sectional view of the water electrolysis cell of 1st Embodiment. 2 is a second partial cross-sectional view of the water electrolysis cell of the first embodiment. It is a schematic diagram of the water electrolysis cell of the 2nd Embodiment. It is a schematic diagram of the 1st modification of a water electrolysis cell. It is a schematic diagram of the 2nd modification of the water electrolysis cell. It is a schematic diagram of the 3rd modification of the water electrolysis cell.

<First Embodiment>
FIG. 1 is a schematic diagram of the water electrolysis cell 1 of the first embodiment. FIG. 2 is a schematic view of a water electrolysis device 6 including a plurality of water electrolysis cells 1. The water electrolysis cell 1 of the present embodiment shown in FIG. 1 is a solid polymer type water electrolysis cell, and a plurality of them are laminated to form a solid polymer type water electrolysis tank (hereinafter, simply referred to as “water electrolysis tank”). 3 (see FIG. 2) is configured. The water electrolysis tank 3 is a so-called water electrolysis stack, and includes a power supply unit 4 that supplies DC power to the water electrolysis tank 3, a water tank 5 that supplies stored water to the water electrolysis cell 1, and the like. The water electrolyzer 6 shown in FIG. 2 is configured. In the present embodiment, the water electrolyzer 6 is a solid polymer type water electrolyzer, and generates oxygen gas and hydrogen gas by electrolyzing the water in the water tank 5 with the electric power of the power supply unit 4. In the present embodiment, each of the plurality of water electrolysis tanks 3 included in the water electrolysis device 6 is formed by stacking four water electrolysis cells 1. However, the number of water electrolysis cells 1 stacked in one water electrolysis tank 3 is not limited to this. In FIGS. 1 and 2, the direction in which the water electrolysis cells 1 are laminated is defined as the z-axis direction, and the two directions orthogonal to each other on the plane perpendicular to the z-axis are defined as the x-axis direction and the y-axis direction. Further, the thickness and size of the members constituting the water electrolysis cell 1 shown in FIG. 1 and the water electrolysis tank 3 shown in FIG. 2 are different from the actual thickness and size for convenience of explanation. The water electrolysis cell 1 corresponds to the "laminated structure" in the claims.

The water electrolysis cell 1 includes a bipolar plate 10, an anode side spacer 20, a membrane electrode joint portion 40, a cathode side spacer 50, and gaskets 31, 36, 61, 66. In the water electrolysis cell 1, the bipolar plate 10, the gasket 31, the anode side spacer 20, the gasket 36, the film electrode joint 40, the gasket 61, the cathode side spacer 50, and the gasket 66 are laminated in this order from the minus side in the z-axis direction. There is. In the present embodiment, the water electrolysis cell 1 has a rectangular shape, and in the water electrolysis tank 3 in which the four water electrolysis cells 1 and one bipolar plate 10 are laminated, the water electrolysis tank 3 is z. Through holes 1a, 1b, 1c, and 1d penetrating in the axial direction are formed at the four corners (see FIG. 2B when the water electrolyzer tank 3 is viewed from the z-axis direction). The through holes 1a, 1b, 1c, and 1d serve as flow paths through which fluids involved in the electrolysis of water in each of the plurality of water electrolysis cells 1 of the water electrolysis tank 3 flow.

The bipolar plate 10 is a substantially rectangular flat plate-shaped member, and is a separator arranged between adjacent water electrolysis cells 1. The bipolar plate 10 is formed with a flow path 11 through which water supplied to the anode-side spacer 20 flows. The flow path 11 is formed in the corner of the bipolar plate 10 on the minus side in the x-axis direction and on the minus side in the y-axis direction, and becomes a part of the through hole 1a (see FIG. 2B). .. An annular grooves 11a and 11b arranged so as to surround the opening of the flow path 11 are formed around the opening of the flow path 11 on the surface of the bipolar plate 10 on the negative side in the z-axis direction. Further, around the opening of the flow path 11 on the positive side surface of the bipolar plate 10 in the z-axis direction, annular grooves 11c and 11d arranged so as to surround the opening of the flow path 11 are formed. In the bipolar plate 10, in addition to the flow path 11, a flow path including the flow path 12 shown in FIG. 1 is formed at each of the four rectangular corners (see FIG. 2B). These flow paths become part of the through holes 1b, 1c, and 1d of the water electrolysis cell 1. Also in these flow paths, an annular groove (for example, an annular groove) arranged so as to surround the opening of these flow paths is provided on each of the positive side surface and the negative side surface of the bipolar plate 10 in the z-axis direction. Grooves 12a, 12b, 12c, 12d) in the flow path 12 shown in FIG. 1 are doubly formed.

The anode-side spacer 20 is a resin plate-shaped member having an opening formed in the central portion, and is arranged on the positive side of the bipolar plate 10 in the z-axis direction. The anode-side spacer 20 is formed with flow paths 20a, 20b, 20c, and 20d, which are part of the through holes 1a, 1b, 1c, and 1d, at the four corners (see FIG. 2B). The anode-side spacer 20 flows along the xy plane of the water electrolysis cell 1 so that the water flowing through the flow path 20a flows over almost the entire surface of the anode-side spacer 20. The details of the structure of the anode side spacer 20 will be described later. The anode-side spacer 20 corresponds to "one of a pair of members" in the claims.

The gasket 31 is a sheet made of Teflon (registered trademark) arranged between the positive side of the bipolar plate 10 in the z-axis direction and the negative side of the anode-side spacer 20 in the z-axis direction. The gasket 31 seals between the bipolar plate 10 and the anode-side spacer 20. The gasket 31 may be EPDM.

The membrane electrode assembly 40 is a substantially rectangular plate-shaped member, and has a resin frame portion 41 and a membrane electrode assembly (Membrane Electrode Assembly, hereinafter referred to as “MEA”) 42. The outer shape of the frame portion 41 is rectangular, and an opening in which the MEA 42 is arranged is formed inside. In the MEA42, electrodes containing a catalyst (not shown) are bonded to both sides of an electrolyte membrane (not shown). The electrolyte membrane is formed from, for example, Nafion® and is permeable to hydrogen ions and water. The anode-side electrode bonded to the negative side of the electrolyte film in the z-axis direction includes an anode-side catalyst layer containing iridium oxide (Ir ₂ O), an anode-side diffusion layer which is a mesh formed of titanium (Ti), and an anode-side diffusion layer. Has. At the anode-side electrode, water is electrolyzed using the electric power supplied by the electrically connected electric power supply unit 4, and oxygen gas and hydrogen ions are generated. Some of the hydrogen ions and water generated at the anode-side electrode move through the electrolyte membrane to the cathode-side electrode bonded to the positive side of the electrolyte membrane in the z-axis direction. The cathode side electrode has a cathode side catalyst layer containing platinum (Pt) and a cathode side diffusion layer which is carbon paper. At the cathode side electrode, hydrogen ions that have passed through the electrolyte membrane are converted into hydrogen gas by using the electric power supplied by the electric power supply unit 4 that is electrically connected.

The gasket 36 is a sheet made of Teflon (registered trademark) arranged between the positive side of the anode side spacer 20 in the z-axis direction and the negative side of the membrane electrode joint 40 in the z-axis direction. The gasket 36 seals between the anode-side spacer 20 and the membrane electrode joint 40. The gasket 36 may be EPDM.

The cathode side spacer 50 is a resin plate-shaped member having an opening formed inside, and is arranged on the plus side in the z-axis direction of the membrane electrode joint portion 40. In the present embodiment, the cathode side spacer 50 uses a member having the same configuration as the anode side spacer 20. Specifically, the cathode side spacer 50 is in a state where the member arranged in the state of the anode side spacer 20 in the water electrolysis cell 1 is turned upside down so that the plus side and the minus side in the z-axis direction are interchanged. Have been placed. In the cathode side spacer 50, flow paths 50a, 50b, 50c, and 50d that are part of the through holes 1a, 1b, 1c, and 1d are formed at the four corners (see FIG. 2B). Details of the structure of the cathode side spacer 50 will be described later. The cathode side spacer 50 corresponds to "the other of the pair of members" in the claims.

The gasket 61 is a sheet made of Teflon (registered trademark) arranged between the positive side of the membrane electrode joint 40 in the z-axis direction and the negative side of the cathode side spacer 50 in the z-axis direction. The gasket 61 seals between the membrane electrode joint 40 and the cathode side spacer 50. The gasket 61 may be EPDM.

In the present embodiment, in the water electrolysis cell 1, the laminate composed of the gasket 36, the membrane electrode joint portion 40, and the gasket 61 is sandwiched between the anode side spacer 20 and the cathode side spacer 50. The laminate composed of the gasket 36, the membrane electrode joint portion 40, and the gasket 61 falls under the "sealing member" in the claims.

The gasket 66 is a sheet made of Teflon (registered trademark) arranged on the positive side of the cathode side spacer 50 in the z-axis direction. The gasket 66 seals between the bipolar plate (two-dot chain line 10A shown in FIG. 1) provided in another water electrolysis cell 1 adjacent to the water electrolysis cell 1 and the cathode side spacer 50. The gasket 66 may be EPDM.

FIG. 3 is a perspective view of the anode side spacer 20. FIG. 4 is a view of the anode side spacer 20 provided in the water electrolysis cell 1 as viewed from the bipolar plate 10 side. FIG. 5 is a view of the anode side spacer 20 provided in the water electrolysis cell 1 as viewed from the membrane electrode joint portion 40 side. FIG. 6 is an enlarged view of part A of FIG. Next, the detailed structure of the anode side spacer 20 will be described. The anode-side spacer 20 includes an outer peripheral portion 21, a manifold portion 22, two ribs 23 and 24, and two gasket retainers 25 and 26. In the present embodiment, the outer peripheral portion 21, the manifold portion 22, the two ribs 23 and 24, and the two gasket retainers 25 and 26 are integrally formed. Each of the ribs 23 and 24 corresponds to the "protrusion" in the claims.

The outer peripheral portion 21 is a flat plate having a rectangular outer shape. A manifold portion 22 is arranged inside the outer peripheral portion 21. On the outer peripheral portion 21, a plurality of groove portions 21a, 21b, 21c, 21d are formed on the outer side of the manifold portion 22 so as to surround the manifold portion 22. The groove portion 21a and the groove portion 21b are formed so as to surround the opening of the manifold portion 22 on the main surface of the peripheral portion 21 on the bipolar plate 10 side (minus side in the z-axis direction). In the present embodiment, the groove portion 21a and the groove portion 21b are formed so as to be parallel to each other as shown in FIG. The groove portion 21c and the groove portion 21d are formed so as to surround the opening of the manifold portion 22 on the main surface of the outer peripheral portion 21 on the film electrode joint portion 40 side (plus side in the z-axis direction). In the present embodiment, the groove portion 21c and the groove portion 21d are formed so as to be parallel to each other as shown in FIG.

The outer peripheral portion 21 is formed with flow paths 20b and 20c, which are a part of the through holes 1b and 1c, respectively. Regarding the flow path 20b, annular groove portions 21e and 21f arranged so as to surround the flow path 20b are formed around the flow path 20b on the surface of the anode side spacer 20 on the minus side in the z-axis direction (FIG. 4). reference). Further, around the flow path 20b on the positive side surface of the anode side spacer 20 in the z-axis direction, annular groove portions 21g and 21h arranged so as to surround the flow path 20b are formed (see FIG. 5). Regarding the flow path 20c, annular grooves 20i and 20j arranged so as to surround the flow path 20c are formed around the flow path 20c on the surface of the anode side spacer 20 on the minus side in the z-axis direction (FIG. 4). reference). Further, around the flow path 20c on the positive side surface of the anode side spacer 20 in the z-axis direction, annular grooves 20k and 20l arranged so as to surround the flow path 20c are formed (see FIG. 5).

As shown in FIGS. 4 and 5, the manifold portion 22 is a substantially parallelogram-shaped portion arranged at a substantially central portion of the anode-side spacer 20. The manifold portion 22 includes two recesses 22a and 22b and a hole portion 22c.

The recess 22a is arranged on the minus side in the x-axis direction in the manifold portion 22. The recess 22a has a substantially triangular cross-sectional shape perpendicular to the z-axis, and is recessed on the plus side in the z-axis direction with respect to the outer peripheral portion 21. In the recess 22a, a flow path 20a, which is a part of the through hole 1a, is formed at the end of the recess 22a on the plus side in the x-axis direction and on the minus side in the y-axis direction (see FIG. 4). A groove 22d is formed around the flow path 20a on the positive side of the recess 22a in the z-axis direction (see FIG. 5).

The recess 22b is arranged on the positive side in the y-axis direction in the manifold portion 22. The recess 22b has a substantially triangular cross-sectional shape perpendicular to the z-axis, and is recessed on the plus side in the z-axis direction with respect to the outer peripheral portion 21. In the recess 22b, a flow path 20d, which is a part of the through hole 1d, is formed at the end of the recess 22b on the plus side in the x-axis direction and on the plus side in the y-axis direction (see FIG. 4). A groove 22e is formed around the flow path 20d on the positive side of the recess 22b in the z-axis direction (see FIG. 5).

The hole 22c is arranged between the positive end of the x-axis of the recess 22a and the negative end of the x-axis of the recess 22b. The hole portion 22c has a rectangular cross-sectional shape perpendicular to the z-axis, and accommodates the flow path structure 27. The flow path structure 27 is a porous body made of titanium (Ti) coated with platinum (Pt) and has electrical conductivity. The flow path structure 27 is formed with a plurality of flow paths of the fluid flowing between the recesses 22a and the recesses 22b.

The rib 23 is arranged on the negative side of the concave portion 22a in the negative direction in the z-axis direction, and is a convex portion protruding from the concave portion 22a in the negative direction of the z-axis. The rib 23 has a plurality of first ribs 23a and a plurality of second ribs 23b.

The first rib 23a is arranged around the flow path 20a. Each of the plurality of first ribs 23a is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 21 (see FIG. 1). As shown in FIG. 4, the plurality of first ribs 23a are arranged so as to extend radially from the flow path 20a, and a gap through which a fluid flows is formed between the adjacent first ribs 23a. At the top of each of the plurality of first ribs 23a, arcuate grooves 23c and 23d arranged so as to surround the flow path 20a are formed.

The second rib 23b is arranged at a position farther from the flow path 20a than the first rib 23a. Each of the plurality of second ribs 23b is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 21 (see FIG. 1). As shown in FIG. 4, the plurality of second ribs 23b are arranged so as to extend radially from the flow path 20a, and a gap through which a fluid flows is formed between the adjacent second ribs 23b. Grooves 23e and 23f arranged in a straight line are formed on the tops of the plurality of second ribs 23b.

The rib 24 is arranged on the negative side of the concave portion 22b in the negative direction in the z-axis direction, and is a convex portion protruding from the concave portion 22b in the negative direction of the z-axis. The rib 24 has a plurality of first ribs 24a and a plurality of second ribs 24b.

The first rib 24a is arranged around the flow path 20d. The plurality of first ribs 24a are formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 21 (see FIG. 1). As shown in FIG. 4, each of the plurality of first ribs 24a is arranged so as to extend radially from the flow path 20d, and a gap through which a fluid flows is formed between the adjacent first ribs 24a. There is. At the top of each of the plurality of first ribs 24a, arcuate grooves 24c and 24d arranged so as to surround the flow path 20d are formed.

The second rib 24b is arranged at a position farther from the flow path 20d than the first rib 24a. Each of the plurality of second ribs 24b is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 21 (see FIG. 1). As shown in FIG. 4, the plurality of second ribs 24b are arranged so as to extend radially from the flow path 20d, and a gap through which a fluid flows is formed between the adjacent second ribs 24b. Grooves 24e and 24f arranged linearly are formed on the tops of the plurality of second ribs 24b.

The gasket retainer 25 is formed in a long shape along the boundary between the recess 22a and the hole 22c, and both ends are connected to the outer peripheral portion 21. The gasket retainer 25 is provided on the negative side of the z-axis in the anode side spacer 20. As a result, the gasket retainer 25 comes into contact with the gasket 31 when the gasket 31 is laminated between the bipolar plate 10 and the anode side spacer 20, and prevents the gasket 31 from falling onto the manifold portion 22. The gasket retainer 25 is provided with a plurality of protrusions 25a on the positive side of the z-axis. The plurality of protrusions 25a are formed so as to protrude from the outer peripheral portion 21 in the stacking direction, and come into contact with the gasket 36 when the gasket 36 is laminated between the anode side spacer 20 and the membrane electrode joint portion 40. , Prevents the gasket 36 from falling onto the manifold portion 22. The gasket retainer 25 corresponds to the "long portion" in the claims.

The gasket retainer 26 is formed in a long shape along the boundary between the recess 22b and the hole 22c, and both ends are connected to the outer peripheral portion 21. The gasket retainer 26 is provided on the negative side of the z-axis in the anode side spacer 20. As a result, the gasket retainer 26 comes into contact with the gasket 31 when the gasket 31 is laminated between the bipolar plate 10 and the anode side spacer 20, and prevents the gasket 31 from falling onto the manifold portion 22. The gasket retainer 26 is provided with a plurality of protrusions 26a on the positive side of the z-axis. The plurality of protrusions 25a are formed so as to protrude from the outer peripheral portion 21 in the stacking direction, and come into contact with the gasket 36 when the gasket 36 is laminated between the anode side spacer 20 and the membrane electrode joint portion 40. , Prevents the gasket 36 from falling onto the manifold portion 22. The gasket retainer 26 corresponds to the "long portion" in the claims.

FIG. 7 is a view of the cathode side spacer 50 provided in the water electrolysis cell 1 as viewed from the membrane electrode joint portion 40 side. FIG. 8 is a view of the cathode side spacer 50 provided in the water electrolysis cell 1 as viewed from the bipolar plate 10A (see FIG. 1) side provided in another water electrolysis cell 1 adjacent to the water electrolysis cell 1. Next, the detailed structure of the cathode side spacer 50 will be described. As described above, the cathode side spacer 50 has the same configuration as the anode side spacer 20, and includes an outer peripheral portion 51, a manifold portion 52, two ribs 53 and 54, and two gasket retainers 55 and 56. , Equipped with. In the present embodiment, the outer peripheral portion 51, the manifold portion 52, the two ribs 53 and 54, and the two gasket retainers 55 and 56 are integrally formed. Each of the ribs 53 and 54 corresponds to the "protrusion" in the claims.

The outer peripheral portion 51 is a flat plate having a rectangular outer shape. On the outer peripheral portion 51, a plurality of groove portions 51a, 51b, 51c, 51d are formed so as to surround the manifold portion 52 on the outside of the manifold portion 52 arranged inside the outer peripheral portion 51. The groove portion 51a and the groove portion 51b are formed on the main surface of the outer peripheral portion 51 on the film electrode joint portion 40 side so as to surround the opening of the manifold portion 52 as shown in FIG. In the present embodiment, the groove portion 51a and the groove portion 51b are formed so as to be parallel to each other. As shown in FIG. 8, the groove portion 51c and the groove portion 51d are formed so as to surround the opening of the manifold portion 52 on the main surface of the outer peripheral portion 51 on the bipolar plate 10A side. In the present embodiment, the groove portion 51c and the groove portion 51d are formed so as to be parallel to each other.

The outer peripheral portion 51 is formed with flow paths 50a and 50d, which are a part of the through holes 1a and 1d, respectively. With respect to the flow path 50a, annular groove portions 51e and 51f arranged so as to surround the flow path 50a are formed around the flow path 50a on the surface of the cathode side spacer 50 on the minus side in the z-axis direction (FIG. 7). reference). Further, around the flow path 50a on the positive side surface of the cathode side spacer 50 in the z-axis direction, annular groove portions 51g and 51h arranged so as to surround the flow path 50a are formed (see FIG. 8). With respect to the flow path 50d, annular grooves 50i and 50j arranged so as to surround the flow path 50d are formed around the flow path 50d on the surface of the cathode side spacer 50 on the minus side in the z-axis direction (FIG. 7). reference). Further, around the flow path 50d on the positive side surface of the cathode side spacer 50 in the z-axis direction, annular grooves 50k and 50l arranged so as to surround the flow path 50d are formed (see FIG. 8).

The manifold portion 52 is a substantially parallelogram-shaped portion arranged at a substantially central portion of the cathode side spacer 50 as shown in FIGS. 7 and 8. The manifold portion 52 includes two recesses 52a and 52b and a hole portion 52c.

The recess 52a is arranged on the minus side in the x-axis direction in the manifold portion 52. The recess 52a has a substantially triangular cross-sectional shape perpendicular to the z-axis, and the negative side in the z-axis direction is recessed with respect to the outer peripheral portion 51. In the recess 52a, a flow path 50b, which is a part of the through hole 1b, is formed at the end of the recess 52a on the minus side in the x-axis direction and on the plus side in the y-axis direction (see FIG. 8). A groove 52d is formed around the flow path 50a on the minus side of the recess 52a in the z-axis direction (see FIG. 7).

The recess 52b is arranged on the positive side in the x-axis direction in the manifold portion 52. The recess 52b has a substantially triangular cross-sectional shape perpendicular to the z-axis, and the plus side in the z-axis direction is recessed with respect to the outer peripheral portion 51. In the recess 52b, a flow path 50c, which is a part of the through hole 1c, is formed at the end of the recess 52b on the plus side in the x-axis direction and on the minus side in the y-axis direction (see FIG. 8). A groove 52e is formed around the flow path 50c on the negative side of the recess 52b in the z-axis direction (see FIG. 7).

The hole 52c is arranged between the positive end of the x-axis of the recess 52a and the negative end of the x-axis of the recess 52b. The hole portion 52c has a rectangular cross-sectional shape perpendicular to the z-axis, and accommodates the flow path structure 57. The flow path structure 57 is a porous body made of titanium (Ti) coated with platinum (Pt) and has electrical conductivity. The flow path structure 57 is formed with a plurality of flow paths of the fluid flowing between the recesses 52a and the recesses 52b.

The rib 53 is arranged on the positive side of the concave portion 52a in the z-axis direction, and is a convex portion protruding from the concave portion 52a in the positive direction of the z-axis. The rib 53 has a plurality of first ribs 53a and a plurality of second ribs 53b.

The first rib 53a is arranged around the flow path 50a. Each of the plurality of first ribs 53a is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 51 (see FIG. 1). As shown in FIG. 8, the plurality of first ribs 53a are arranged so as to extend radially from the flow path 50b, and a gap through which a fluid flows is formed between the adjacent first ribs 53a. At the top of each of the plurality of first ribs 53a, arcuate grooves 53c and 53d arranged so as to surround the flow path 50b are formed.

The second rib 53b is arranged at a position farther from the flow path 50a than the first rib 53a. Each of the plurality of second ribs 53b is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 51 (see FIG. 1). As shown in FIG. 8, the plurality of second ribs 53b are arranged so as to extend radially from the flow path 50a, and a gap through which a fluid flows is formed between the adjacent second ribs 53b. Grooves 53e and 53f arranged in a straight line are formed on the tops of the plurality of second ribs 53b.

The rib 54 is a convex portion that is arranged on the positive side of the concave portion 52b in the z-axis direction and protrudes from the concave portion 52b in the positive direction of the z-axis. The rib 54 has a plurality of first ribs 54a and a plurality of second ribs 54b.

The first rib 54a is arranged around the flow path 50c. The plurality of first ribs 54a are formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 51 (see FIG. 1). As shown in FIG. 8, each of the plurality of first ribs 54a is arranged so as to extend radially from the flow path 50c, and a gap through which a fluid flows is formed between the adjacent first ribs 54a. There is. At the top of each of the plurality of first ribs 54a, arcuate grooves 54c and 54d arranged so as to surround the flow path 50c are formed.

The second rib 54b is arranged at a position farther from the flow path 50c than the first rib 54a. Each of the plurality of second ribs 54b is formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 51 (see FIG. 1). As shown in FIG. 8, the plurality of second ribs 54b are arranged so as to extend radially from the flow path 50c, and a gap through which a fluid flows is formed between the adjacent second ribs 54b. Grooves 54e and 54f arranged in a straight line are formed on the tops of the plurality of second ribs 54b.

The gasket retainer 55 is formed in a long shape along the boundary between the recess 52a and the hole 52c, and both ends are connected to the outer peripheral portion 51. The gasket retainer 55 is provided on the positive side of the z-axis in the cathode side spacer 50. As a result, the gasket retainer 55 comes into contact with the gasket 66 when the gasket 66 is laminated between the bipolar plate 10A and the cathode side spacer 50, and prevents the gasket 66 from falling onto the manifold portion 52. The gasket retainer 55 is provided with a plurality of protrusions 55a on the minus side of the z-axis. The plurality of protrusions 55a are formed so as to protrude from the outer peripheral portion 51 in the stacking direction, and come into contact with the gasket 61 when the gasket 61 is laminated between the cathode side spacer 50 and the membrane electrode joint portion 40. , The gasket 61 is prevented from falling onto the manifold portion 52. The gasket retainer 55 corresponds to the "long portion" in the claims.

The gasket retainer 56 is formed in a long shape along the boundary between the recess 52b and the hole 52c, and both ends are connected to the outer peripheral portion 51. The gasket retainer 56 is provided on the positive side of the z-axis in the cathode side spacer 50. As a result, the gasket retainer 56 comes into contact with the gasket 66 when the gasket 66 is laminated between the bipolar plate 10A and the cathode side spacer 50, and prevents the gasket 66 from falling onto the manifold portion 52. The gasket retainer 56 is provided with a plurality of protrusions 56a on the minus side of the z-axis. The plurality of protrusions 56a are formed so as to protrude from the outer peripheral portion 51 in the stacking direction, and come into contact with the gasket 61 when the gasket 61 is laminated between the cathode side spacer 50 and the membrane electrode joint portion 40. , The gasket 61 is prevented from falling onto the manifold portion 52. The gasket retainer 56 corresponds to the "long portion" in the claims.

Next, the first feature of the water electrolysis cell 1 of the present embodiment will be described. In the water electrolysis cell 1, a plurality of bipolar plates 10, the anode-side spacer 20, and the cathode-side spacer 50 are provided so as to surround the flow paths and openings formed in the anode-side spacer 20 and the cathode-side spacer 50, respectively. A groove is formed.

FIG. 9 is a schematic diagram illustrating the operation of the first feature of the water electrolysis cell 1. FIG. 9 schematically shows the deformation of the gasket 36 and the gasket 61 when the gasket 36 and the gasket 61 are sandwiched between the anode side spacer 20 and the cathode side spacer 50 via the membrane electrode joint portion 40. FIG. 9A shows a state before the anode side spacer 20 and the cathode side spacer 50 are fastened, and FIG. 9B shows the anode side spacer 20 and the cathode side spacer 50 being fastened together. It shows the state after the cathode.

As shown in FIG. 9, when the anode side spacer 20 and the cathode side spacer 50 in which the gasket 36 and the gasket 61 are arranged are fastened, a part of the surface 36a of the gasket 36 is deformed, and the groove portions 21c and 21d are formed. (Protruding portion 37 shown in FIG. 9B). As a result, a labyrinth seal is formed between the anode-side spacer 20 and the gasket 36, so that gas leakage from between the anode-side spacer 20 and the gasket 36 is suppressed. Further, when the anode side spacer 20 and the cathode side spacer 50 are fastened, a part of the surface 61b of the gasket 61 is deformed and protrudes inward of the groove portions 51a and 51b (the protruding portion 63 shown in FIG. 9B). As a result, a labyrinth seal is formed between the cathode side spacer 50 and the gasket 61, so that gas leakage from between the cathode side spacer 50 and the gasket 61 is suppressed. In this state, the manifold portion 22 of the anode-side spacer 20 and the manifold portion 52 of the cathode-side spacer 50 are maintained from each other by the labyrinth seal described above.

In the water electrolysis cell 1 of the present embodiment, grooves 11c, 11d, 12c, and 12d are formed on the gasket 31 side of the bipolar plate 10 so as to project a part of the surface of the gasket 31 (see FIG. 1). 21a, 21b, 21e, 21f, 21i, 21j are formed on the gasket 31 side of the anode side spacer 20 so as to project a part of the surface of the gasket 31 (see FIG. 4). 21c, 21d, 21g, 21h, 21k, 21l are formed on the membrane electrode joint portion 40 side of the anode side spacer 20 so as to project a part of the surface of the gasket 36 (see FIG. 5). Grooves 51a, 51b, 51e, 51f, 51i, 51j are formed on the membrane electrode joint 40 side of the cathode side spacer 50 so as to project a part of the surface of the gasket 61 (see FIG. 7). Grooves 51c, 51d, 51g, 51h, 51k, 51l are formed on the bipolar plate 10A side of the cathode side spacer 50 so as to project a part of the surface of the gasket 66 (see FIG. 8). A part of the surface of the gasket provided in the water electrolysis cell 1 protrudes into the groove of the adjacent bipolar plate or spacer, so that the leakage of fluid from the inside can be suppressed.

Next, the second feature of the water electrolysis cell 1 of the present embodiment will be described. In the water electrolysis cell 1 of the present embodiment, each of the ribs 23 and 24 of the anode side spacer 20 is located at a position overlapping the groove portion formed in the cathode side spacer 50 in the stacking direction along the extending direction of the groove portion. They are installed side by side. Further, each of the ribs 53 and 54 of the cathode side spacer 50 is provided side by side along the extending direction of the groove portion at a position overlapping the groove portion formed in the anode side spacer 20 in the stacking direction.

FIG. 10 is a permeation enlarged view of the water electrolysis cell 1 of the first embodiment. FIG. 11 is a transmission enlarged view of the water electrolysis cell of the comparative example. The water electrolysis cell 9 of the comparative example is provided with ribs 23 and 24 provided in the manifold portion 22 of the anode side spacer 20 and ribs 53 and 54 provided in the manifold portion 52 of the cathode side spacer 50 in the water electrolysis cell 1. Not done. Further, as shown in FIG. 11, the water electrolysis cell 9 of the comparative example does not include the gasket retainers 25, 26, 55, 56 provided in the water electrolysis cell 1.

In the water electrolysis cell 9 of the comparative example, as shown in FIG. 11, a part of the groove portion of the cathode side spacer 50 overlaps the manifold portion 22 of the anode side spacer 20 in the stacking direction (z-axis direction). Specifically, in FIG. 11, a part of the groove portions 51e, 51f, 51h and 51g and a part of the groove portions 51a, 51b, 51c and 51d shown by hatching with dots are the manifold portion 22 of the anode side spacer 20. Overlaps on. A part of the groove portions 21c and 22d of the anode side spacer 20 also overlaps with the manifold portion 22 of the anode side spacer 20.

Further, in the water electrolysis cell 9 of the comparative example, as shown in FIG. 11, a part of the groove portion of the anode side spacer 20 overlaps the manifold portion 52 of the cathode side spacer 50 in the stacking direction. Specifically, in FIG. 11, a part of the groove portions 21e, 21f, 21g, 21h and a part of the groove portions 21a, 21b, 21c, 21d shown by dot hatching are the manifold portions 52 of the cathode side spacer 50. Overlap on. A part of the groove portions 51c and 51d of the cathode side spacer 50 also overlaps with the manifold portion 52 of the cathode side spacer 50.

In the water electrolysis cell 1 of the comparative example, as described above, a part of one groove portion of the anode side spacer 20 or the cathode side spacer 50 is a manifold portion of the other anode side spacer 20 or the cathode side spacer 50 in the stacking direction. It overlaps with. Therefore, since the surface of the gasket facing the manifold portion is not supported by the spacer, the gasket is less likely to be deformed toward the inside of the groove portion, and it is difficult to maintain the sealing property of the gasket.

On the other hand, in the water electrolysis cell 1 of the present embodiment, in the stacking direction, one manifold portion of the anode side spacer 20 or the cathode side spacer 50 is positioned so that the other groove portion of the anode side spacer 20 or the cathode side spacer 50 overlaps. Ribs are provided (see FIG. 10). Specifically, the manifold portion 22 of the anode side spacer 20 is provided with first ribs 23a arranged along the extending direction of a part of the groove portions 51e, 51f, 51h, and 51g, and the groove portion 51a is provided. , 51b, 51c, 51d are provided with second ribs 23b arranged along a partial extending direction. Further, the manifold portion 52 of the cathode side spacer 50 is provided with first ribs 53a arranged along the extending direction of a part of the groove portions 21e, 21f, 21g, 21h, and the groove portions 21a, 21b, Second ribs 53b arranged along a part of the extending direction of 21c and 21d are provided. As a result, in one of the anode side spacer 20 and the cathode side spacer 50, the manifold portion is formed by the total thickness of the manifold portion and the rib at the position where the other groove portion of the anode side spacer 20 or the cathode side spacer 50 overlaps. The value is close to the thickness of the non-existent portion, for example, the outer peripheral portion. Therefore, since the gasket can be supported even in the manifold portion, the gasket is easily deformed by stress concentration on the edges of the grooves formed in the anode side spacer 20 and the cathode side spacer 50. When the gasket is easily deformed, the labyrinth seal is easily formed by the protrusion inward of the groove portion, so that the sealing property of the manifold portion by the gasket can be improved.

In the water electrolysis cell 1 of the present embodiment, the same applies to the end portion opposite to the end portion shown in FIG. 10, that is, the recess 22b of the anode side spacer 20 and the recess 52b of the cathode side spacer 50. It has a configuration. Specifically, the recess 22b of the anode side spacer 20 is provided with first ribs 24a arranged along the extending direction of a part of the groove portions 51i, 51j, 51k, 51l, and the groove portions 51a, Second ribs 24b arranged along the extending direction of a part of 51b, 51c, 51d are provided. Further, in the recess 52b of the cathode side spacer 50, first ribs 54a arranged along the extending direction of a part of the groove portions 21i, 21j, 21k, 21l are provided, and the groove portions 21a, 21b, 21c are provided. , 21d is provided with a second rib 54b arranged along a part of the extending direction. As a result, the rib 24 of the anode side spacer 20 and the rib 54 of the cathode side spacer 50 have the same effects as the ribs 23 and 53 described above.

FIG. 12 is a diagram illustrating the operation of the water electrolysis cell 1. Next, the operation of the water electrolysis cell 1 will be described. The water supplied by the water tank 5 (two-dot chain line arrow F11 in FIG. 12) flows through the flow path 20a of the anode-side spacer 20 via the flow path 11 of the bipolar plate 10. A part of the water flowing through the flow path 20a flows into the flow path structure 27 through the recess 22a of the manifold portion 22 (two-dot chain line arrow F12 in FIG. 12). Further, of the water flowing through the flow path 20a, the remaining water that has not flowed into the recess 22a is supplied to another water electrolysis cell 1 adjacent to the water electrolysis cell 1 through the flow path 20a (FIG. 12). Two-dot chain arrow F13).

FIG. 13 is a first partial cross-sectional view of the water electrolysis cell 1 and is a cross-sectional perspective view of the anode-side spacer 20 for explaining the flow of water from the flow path 20a through the recess 22a to the hole 22c. FIG. 14 is a second partial cross-sectional view of the water electrolysis cell 1 and is an enlarged cross-sectional view of the water electrolysis cell 1 showing the flow of water shown in FIG. As shown in FIG. 13, the water flowing from the flow path 20a into the recess 22a flows on the bipolar plate 10 side (minus side of the z-axis) of the anode side spacer 20. The water flowing into the recess 22a flows between the adjacent ribs in the first rib 23a and between the adjacent ribs in the second rib 23b. The water flowing through the recess 22a moves from the bipolar plate 10 side to the membrane electrode joint 40 side by the gasket retainer 25 arranged on the bipolar plate 10 side before flowing into the hole 22c (see FIG. 14). .. The water that has moved to the membrane electrode joint 40 side passes between the plurality of protrusions 25a of the gasket retainer 25 and flows into the flow path structure 27 housed in the hole 22c (see FIG. 14).

Returning to FIG. 12, the water flowing into the flow path structure 27 spreads over the entire surface of the hole portion 22c (two-dot chain line arrow F14 in FIG. 12). Most of the water that has spread over the entire surface of the flow path structure 27 passes through the anode-side diffusion layer of the membrane electrode junction 40 and reaches the anode-side catalyst layer. The anode-side catalyst layer is electrolyzed from water reaching the anode-side catalyst layer to generate oxygen gas and hydrogen ions by using the electric power supplied by the power supply unit 4. The generated oxygen gas, together with the unelectrolyzed water, flows through the through hole 1d through the recess 22b of the anode side spacer 20 and is discharged to the outside of the water electrolytic cell 1 (two-dot chain arrow in FIG. 12). F15).

The hydrogen ions generated in the anode-side catalyst layer pass through the electrolyte membrane together with a part of water (accompanying water) (two-dot chain line arrow F16 in FIG. 12) and reach the cathode-side electrode. The cathode side electrode uses the electric power supplied by the electric power supply unit 4 to generate hydrogen gas from hydrogen ions. The generated hydrogen gas and accompanying water pass through the flow path structure 57 (two-dot chain line arrow F17 in FIG. 12) and pass between the plurality of protrusions 55a of the gasket retainer 55. As shown in FIG. 12, the hydrogen gas passing between the plurality of protrusions 55a moves from the membrane electrode joint 40 side to the bipolar plate 10A side, and is between the adjacent ribs in the second rib 53b and the first rib. It flows between adjacent ribs in 53a, passes through the flow path 50b, and is discharged to the outside of the water electrolysis cell 1 (two-dot chain line arrow F18 in FIG. 12).

According to the water electrolysis cell 1 of the present embodiment described above, in the water electrolysis cell 1, groove portions 21a, 21b, 21c, 21d and the like are formed on the anode side spacer 20 so as to surround the manifold portion 22. There is. Further, the cathode side spacer 50 is formed with groove portions 51a, 51b, 51c, 51d and the like so as to surround the manifold portion 52. When the anode-side spacer 20 and the cathode-side spacer 50 are laminated, the surfaces of the gaskets 36 and 61 are deformed and protrude toward the inside of these grooves to form the gaskets 36 and 61 and the membrane electrode joint portion 40. The sealing property between the anode-side spacer 20 and the cathode-side spacer 50 can be maintained. Further, the manifold portion 22 of the anode side spacer 20 is provided with ribs 23 and 24 arranged along the extending direction of the groove portion of the cathode side spacer 50 in the stacking direction. Further, the manifold portion 52 of the cathode side spacer 50 is provided with ribs 53 and 54 arranged along the extending direction of the groove portion of the anode side spacer 20 in the stacking direction. As a result, in one of the anode side spacer 20 and the cathode side spacer 50, the total thickness of the manifold portion and the protrusion portion is the thickness of the outer peripheral portion at the position where the other groove portion of the anode side spacer 20 or the cathode side spacer 50 overlaps. The value is close to. That is, since the water electrolysis cell 1 has a small gap at the position where it overlaps with the groove portion in the stacking direction, the structural strength in the stacking direction can be increased. As a result, the gaskets 31, 36, 61, and 66 can be supported so that the surface is easily deformed toward the inside of the groove portion at the position where the groove portion overlaps in the stacking direction. Further, the ribs 23 and 24 form a gap between adjacent ribs in the manifold portion 22 through which a fluid can flow. The ribs 53 and 54 form a gap between adjacent ribs in the manifold portion 52 through which a fluid can flow. As described above, the ribs 23, 24, 53, 54 form a gap in the manifold portions 22, 52 through which the fluid can flow between the adjacent ribs, which hinders the flow of the fluid in the manifold portions 22, 52. It's getting harder. Therefore, it is possible to improve the sealing property of the manifold portions 22 and 52 by the gaskets 31, 36, 61 and 66 while circulating the fluid in the manifold portions 22 and 52.

Further, in the water electrolysis cell 1 of the present embodiment, the total thickness of the manifold portion and the rib in each of the anode side spacer 20 or the cathode side spacer 50 is a value close to the thickness of the outer peripheral portion. This makes it easier to grasp the physical contact state between the members stacked between the two bipolar plates 10 and 10A, so it is relatively easy to manage the electrical resistance between the two bipolar plates 10 and 10A. can do.

Further, in the water electrolysis cell 1 of the present embodiment, in the anode side spacer 20, the manifold portion 22 and the ribs 23 and 24 are integrally formed, and in the cathode side spacer 50, the manifold portion 52 and the ribs 53 and 54 are formed. Is formed integrally. As a result, it is possible to increase the cross-sectional area between adjacent ribs while maintaining the structural strength, as compared with the case where the rib is a separate part from the manifold portion.

Further, in the water electrolysis cell 1 of the present embodiment, in the anode side spacer 20, the top of the first rib 23a has grooves 23c and 23d extending in the extending direction such as the groove portion 51e of the cathode side spacer 50. It is formed. Further, on the top of the second rib 23b, grooves 23e and 23f extending in the extending direction such as the groove portion 51a of the cathode side spacer 50 are formed. Grooves 24c and 24d extending in the extending direction such as the groove 51i of the cathode side spacer 50 are formed on the top of the first rib 24a. Grooves 24e and 24f extending in the extending direction such as the groove 51a of the cathode side spacer 50 are formed on the top of the second rib 24b. In the cathode side spacer 50, grooves 53c and 53d extending in the extending direction such as the groove portion 21e of the anode side spacer 20 are formed on the top of the first rib 53a. Further, on the top of the second rib 53b, grooves 53e and 53f extending in the extending direction such as the groove portion 21a of the anode side spacer 20 are formed. Grooves 54c and 54d extending in the extending direction such as the groove portion 21i of the anode side spacer 20 are formed on the top of the first rib 54a. At the top of the second rib 54b, grooves 54e and 54f extending in the extending direction such as the groove portion 21a of the anode side spacer 20 are formed. As a result, for example, the surface of the gasket 31 facing the top of the rib 23 is deformed toward the inside of the grooves 23c, 23d, 23e, 23f formed in the top, and the seal between the gasket 31 and the rib 23 is formed. Can maintain sex. Therefore, in the manifold portions 22 and 52, it is possible to prevent the fluid from flowing between the gasket and the ribs, so that the fluid can flow between the ribs adjacent to each other.

Further, in the water electrolysis cell 1 of the present embodiment, the ribs 23 and 24 of the anode side spacer 20 are formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 21. The ribs 53 and 54 of the cathode side spacer 50 are formed so that the height of the top thereof is aligned with the height of the outer peripheral portion 51. As a result, in each of the anode side spacer 20 and the cathode side spacer 50, the total thickness of the manifold portion and the rib in the stacking direction is almost the same as the thickness of the outer peripheral portion, so that the gasket is more easily deformed. Therefore, the sealing property of the manifold portion by the gasket can be further improved.

Further, in the water electrolysis cell 1 of the present embodiment, the anode-side spacer 20 has a direction in which the water flow direction from the recess 22a to the hole 22c intersects the direction along the recess 22a from the direction along the recess 22a. A gasket presser 25 for switching to is provided. Further, the anode-side spacer 20 includes a gasket retainer 26 formed in a long shape along the boundary between the recess 22b and the hole 22c in the manifold portion 22. As a result, in the anode side spacer 20, the gasket 36 can be pressed by the recesses 22a and 22b, and the gasket 31 can be pressed by the gasket retainers 25 and 26. Further, by switching the flow direction of water from the recess 22a to the hole 22c, hydrogen ions and accompanying water can be easily supplied to the manifold portion 52 of the cathode side spacer 50 via the MEA 42.

Further, in the water electrolysis cell 1 of the present embodiment, an electrolyte membrane formed of Nafion is arranged at the membrane electrode joint portion 40, and the gasket 36 is formed of Teflon (registered trademark). In this case, since the recesses 22a and 22b hold down the gasket 36, it is possible to prevent water from entering between the gasket 36 and the electrolyte membrane. As a result, the swelling of the water electrolyte membrane can be suppressed by contact with water, so that the reduction in the cross-sectional area of the manifold portion 22 due to the extrusion of the gasket due to the swelling of the Nafion membrane can be suppressed.

Further, in the water electrolysis cell 1 of the present embodiment, each of the gasket pressers 25 and 26 is formed with a plurality of protrusions 25a and 26a protruding from the outer peripheral portion 21 in the stacking direction. As a result, the plurality of protrusions 25a and 26a come into contact with the gasket 36 and can suppress the drop of the gasket 36 into the hole portion 22c, so that the decrease in the flow path cross-sectional area of the hole portion 22c can be suppressed. .. Further, each of the gasket retainers 55 and 56 is formed with a plurality of protrusions 55a and 56a protruding from the outer peripheral portion 51 in the stacking direction. As a result, the plurality of protrusions 55a and 56a come into contact with the gasket 61 and can suppress the drop of the gasket 61 into the hole portion 52c, so that the decrease in the flow path cross-sectional area of the hole portion 52c can be suppressed. ..

Further, in the water electrolysis cell 1 of the present embodiment, oxygen gas and hydrogen ions are generated by supplying water to the anode side spacer 20, and the cathode side spacer 50 has the anode side spacer 20 and the cathode side spacer 50. Hydrogen gas is generated from hydrogen ions supplied through the membrane electrode junction 40 between them. When the solid polymer type water electrolysis cell 1 has the above-described configuration, water flowing through the manifold portion 22 of the anode side spacer 20 and hydrogen gas flowing through the manifold portion 52 of the cathode side spacer 50 leak to the outside. It can be suppressed.

<Second Embodiment>
FIG. 15 is a first diagram illustrating the operation of the water electrolysis cell 2 of the second embodiment. The water electrolysis cell 2 of the second embodiment is different from the water electrolysis cell 1 of the first embodiment (FIG. 1) in the orientation of the spacer arrangement with respect to the stacking direction and the shape of the spacer.

The water electrolysis cell 2 of the present embodiment includes a bipolar plate 10, an anode side spacer 70, a membrane electrode joint portion 40, a cathode side spacer 80, and gaskets 31, 36, 61, 66. The anode-side spacer 70 is a resin plate-shaped member having an opening formed in the central portion, and is arranged on the positive side of the bipolar plate 10 in the z-axis direction. The cathode side spacer 80 is a resin plate-shaped member having an opening formed inside, and is arranged on the positive side of the membrane electrode joint portion 40 in the z-axis direction.

The anode-side spacer 70 includes an outer peripheral portion 21, a manifold portion 22, and two ribs 23 and 24. The anode-side spacer 70 does not have two gasket retainers as compared with the anode-side spacer 20 of the first embodiment, and as shown in FIG. 15, the two ribs 23 and 24 are on the membrane electrode joint 40 side. It is different from being placed in.

The cathode side spacer 80 includes an outer peripheral portion 51, a manifold portion 52, and two ribs 53 and 54. Compared to the cathode side spacer 80 of the first embodiment, the cathode side spacer 80 does not have two gasket retainers, and as shown in FIG. 15, the two ribs 53 and 54 are on the membrane electrode joint portion 40 side. It is different from being placed in.

According to the water electrolysis cell 2 of the present embodiment described above, the ribs 23 are arranged in the manifold portion 22 of the anode side spacer 70 along the extending direction of the groove portion of the cathode side spacer 80 in the stacking direction. , 24 are provided. Further, the manifold portion 52 of the cathode side spacer 80 is provided with ribs 53 and 54 arranged along the extending direction of the groove portion of the anode side spacer 70 in the stacking direction. As a result, in one of the anode side spacer 70 or the cathode side spacer 80, even at the position where the other groove portion of the anode side spacer 20 or the cathode side spacer 50 overlaps, the gaskets 36 and 61 are suppressed from falling into the manifold portions 22 and 52. The gaskets 31, 36, 61 and 66 can be supported. Further, since the ribs 23, 24, 53, and 54 form a gap in the manifold portions 22 and 52 through which the fluid can flow between the adjacent ribs, the ribs 23, 24, 53, and 54 are less likely to obstruct the flow of the fluid in the manifold portions 22 and 52. ing. Therefore, it is possible to improve the sealing property of the manifold portions 22 and 52 by the gaskets 31, 36, 61 and 66 while circulating the fluid in the manifold portions 22 and 52.

<Modified example of this embodiment>
The present invention is not limited to the above embodiment, and can be carried out in various embodiments without departing from the gist thereof, and for example, the following modifications are also possible.

[Modification 1]
In the above embodiment, the water electrolysis cell as a laminated structure is applied to a solid polymer type water electrolysis cell. However, the field to which the laminated structure is applied is not limited to this. It may be applied to a cell provided in a polymer electrolyte fuel cell that generates electricity by a chemical reaction between hydrogen and oxygen.

[Modification 2]
In the above embodiment, the ribs are formed so that the height of the top is aligned with the height of the outer periphery. However, the relationship between the height of the top of the rib and the height of the outer periphery is not limited to this. By aligning the height of the top of the rib with the height of the outer periphery, the gasket is more easily deformed, so that the sealing property of the manifold portion by the gasket can be further improved.

[Modification 3]
In the above-described embodiment, the top of one rib of the anode-side spacer 20 or the cathode-side spacer 50 extends in a direction along the extending direction of the groove formed on the other of the anode-side spacer 20 or the cathode-side spacer 50. It was assumed that a groove would be formed. However, the top of the rib may not have a groove.

[Modification 4]
In the first embodiment, the anode-side spacer 20 and the cathode-side spacer 50 each have gasket retainers 25, 26, 55, and 56. However, the gasket retainer may not be present.

FIG. 16 is a schematic view of a first modification of the water electrolysis cell. As in the water electrolytic cell 1 shown in FIG. 16, even if there is no gasket presser, the rib can support the gasket even in the manifold portion, so that the gasket is easily deformed and the sealing property of the manifold portion by the gasket is improved. Can be improved. Further, one of the anode-side spacer 20 and the cathode-side spacer 50 may have a gasket retainer.

[Modification 5]
In the second embodiment, each of the anode-side spacer 70 and the cathode-side spacer 80 does not have a gasket retainer. However, it may have a gasket retainer.

FIG. 17 is a schematic view of a second modification of the water electrolysis cell. In the water electrolysis cell 2 shown in FIG. 17, the anode-side spacer 70 is provided with gasket retainers 25 and 26, and the cathode-side spacer 80 is provided with gasket retainers 55 and 56. As a result, the gasket 31 can be pressed by the gasket pressers 25 and 26, and the gasket 66 can be pressed by the gasket pressers 55 and 56. Therefore, it is possible to suppress the drop of the gasket 31 into the hole 22c and the drop of the hole 52c of the gasket 66.

[Modification 6]
In the above-described embodiment, the flow path structures 27 and 57 accommodated in the manifold portions 22 and 52, respectively, are considered to be a porous body having a plurality of flow paths. However, the configuration of the flow path structure is not limited to this.

FIG. 18 is a schematic view of a third modification of the water electrolysis cell. In the water electrolysis cell 1 shown in FIG. 18, the flow path structures 28 and 58 housed in the manifold portions 22 and 52 have flow paths 28a and 58a on the MEA42 side. The water flowing through the recess 22a flows through the flow path 28a to generate oxygen gas and hydrogen ions. The generated hydrogen ions are sent to the flow path 58a through the MEA42. In the flow path 58a, hydrogen gas is generated from hydrogen ions. Even if the flow path structure of the spacer has such a configuration, the gasket can be supported by the ribs and the gasket retainer, so that the gasket is easily deformed. This makes it possible to improve the sealing performance of the manifold portion by the gasket.

Although this embodiment has been described above based on the embodiments and modifications, the embodiments described above are for facilitating the understanding of the present embodiment and do not limit the present embodiment. This aspect may be modified or improved without departing from its spirit and claims, and this aspect includes its equivalent. Further, if the technical feature is not described as essential in the present specification, it may be deleted as appropriate.

1, 2, ... Water electrolysis cell 3 ... Water electrolysis tank 6 ... Water electrolysis device 10, 10A ... Bipolar plate 20, 70 ... Anode side spacer 21 ... Outer peripheral part 21c, 21d, 51a, 51b ... Groove part 22, 52 ... Manifold part 22a , 22b, 52a, 52b ... Recessed portions 22c, 52c ... Holes 23, 24, 53, 54 ... Ribs 23c, 23d, 23e, 23f, 24c, 24d, 24e, 24f, 53c, 53d, 53e, 53f, 54c, 54d , 54e, 54f ... Grooves 25a, 26a, 55a, 56a ... Projections 31, 36, 61, 66 ... Cathode 50, 80 ... Cathode side spacers 52a ... Recesses 52a ... Manifold portion

Claims (6)

It is a laminated structure
A pair of members to be laminated, the main surfaces of which are laminated so as to face each other, and a pair of members on which a manifold portion through which a fluid flows is formed.
A seal member arranged between the pair of members and
A groove portion formed so as to surround the manifold portion on the main surface of the pair of members, and a groove portion.
A plurality of protrusions formed on the manifold portion of the pair of members and projecting in the stacking direction of the pair of members are provided.
The plurality of protrusions formed on one of the pair of members
In the stacking direction, they are provided side by side along the extending direction of the groove portion at a position overlapping the groove portion formed on the other side of the pair of members.
In a state where the seal member is arranged between the groove portion formed on the other side of the pair of members, the fluid can flow between the protrusions adjacent to each other.
Laminated structure. The laminated structure according to claim 1.
At the top of each of the plurality of protrusions formed on one of the pair of members, a groove extending in a direction along the extending direction of the groove formed on the other of the pair of members is formed. ,
Laminated structure. The laminated structure according to claim 1 or 2, wherein the laminated structure is used.
The pair of members are formed on the outside of the manifold portion of the main surface and include an outer peripheral portion having the groove portion.
The manifold portion is recessed in the main surface with respect to the outer peripheral portion.
The protrusion is formed so that the height of the top is aligned with the height of the outer periphery.
Laminated structure. The laminated structure according to claim 3.
The manifold portion includes a recess recessed with respect to the outer peripheral portion and a hole portion adjacent to the recess.
The pair of members are formed in a long shape along the boundary between the recess and the hole, and the flow direction of the fluid from the recess to the hole is from the direction along the recess to along the recess. It has a long part that switches in the direction that intersects with the direction of the water.
Laminated structure. The laminated structure according to claim 4, wherein the laminated structure is used.
The long portion is
Both ends are connected to the outer peripheral portion in the hole portion, respectively.
A plurality of protrusions protruding from the outer peripheral portion in the stacking direction are formed.
Laminated structure. It is a solid polymer type water electrolysis cell.
The laminated structure according to any one of claims 1 to 5 is provided.
One of the pair of members was used as an anode-side spacer, and the other was used as a cathode-side spacer.
Solid polymer type water electrolysis cell.

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