JP2023119076A - Composite body - Google Patents

Abstract

To provide a composite body that suppresses a joint by a joining member from being damaged due to displacement of a cylindrical member.SOLUTION: A composite body comprises: a first member in which a first open hole 107 is formed penetrating in a first direction Z, and a cylindrical upright part 530 is formed protruding to one side in the first direction Z and enclosing the first open hole 107; a cylindrical member 27 which is connected to the upright part 530 so as to communicate with the first open hole 107 of the first member; a second member 420 which is disposed to the first member at the other side in the first direction Z; and a joining member 197 which is disposed between the first member and the second member 420, and which is disposed in a periphery of the first open hole 107 in a first direction view. The joining member 197, in the first direction view, is disposed outward of a connecting periphery part of the first member that is a section of the cylindrical member 27 enclosing contour lines of the upright part 530 and the connecting member 197.SELECTED DRAWING: Figure 10

Description

The technology disclosed by this specification relates to complexes.

A solid oxide fuel cell (hereinafter referred to as "SOFC") having an electrolyte layer containing a solid oxide is known as one type of fuel cell that generates electricity using an electrochemical reaction between hydrogen and oxygen. It is A fuel cell single cell (hereinafter simply referred to as a "single cell"), which is a structural unit of an SOFC, consists of an electrolyte layer and an air stream facing each other in a predetermined direction (hereinafter referred to as a "first direction") across the electrolyte layer. Including poles and anodes.

An SOFC generally includes a power generation block in which a plurality of power generation units having single cells are arranged side by side in a first direction, and a manifold communicating with a gas chamber facing a specific electrode, which is one of the fuel electrode and the air electrode. is utilized in the form of a fuel cell stack in which is formed. The fuel cell stack further includes end members, gas passage members, and joint members. The end member is arranged on one side of the power generation block in the first direction. The end member is formed with an end through hole penetrating in the first direction and communicating with the manifold. The gas passage member is arranged on the one side (the side opposite to the power generation block) in the first direction with respect to the end member. The gas passage member is a cylindrical body formed with a gas through hole penetrating in the first direction and communicating with the end through hole. The joining member is arranged between the power generation block and the end member (see Patent Document 1, for example).

JP 2017-10804 A

By the way, the inventors of the present application have studied a fuel cell stack including an end member having an erected portion. The standing portion has a tubular shape that protrudes to the one side in the first direction and surrounds the end through hole. The gas passage member is connected to the upright portion of the end member. In such a configuration, when an external force is applied to the gas passage member and the gas passage member is displaced, the connection peripheral portion of the end member, which is the portion surrounding the outline of the connection portion between the standing portion and the gas passage member, is likely to deform. Here, if the joint member is arranged at a position overlapping the connection peripheral portion of the end member when viewed from the first direction, stress is applied to the joint member as the connection peripheral portion deforms, and the joint member There is a problem that the joint may be damaged due to

In addition, such a subject is an electrolytic cell including an electrolytic single cell, which is a structural unit of a solid oxide type electrolytic cell (hereinafter referred to as "SOEC") that generates hydrogen using the electrolysis reaction of water. It is also a common problem for electrolysis cell stacks with multiple units. In this specification, the fuel cell single cell and the electrolysis single cell are collectively referred to as an electrochemical reaction single cell, the fuel cell power generation unit and the electrolysis cell unit are collectively referred to as an electrochemical reaction unit, and a fuel cell stack. The electrolysis cell stack is collectively called an electrochemical reaction cell stack. Moreover, such problems are not limited to SOFCs and SOECs, but are common to other types of fuel cells and electrolytic cells. Furthermore, such a problem is not limited to the electrochemical reaction cell stack or the like, but the first member provided with the first through hole and the standing portion, the tubular member connected to the standing portion, and the second and a joint member for joining the first member and the second member.

This specification discloses a technology capable of solving the above-described problems.

The technology disclosed in this specification can be implemented, for example, in the following forms.

(1) The composite disclosed in the present specification has a first through hole that penetrates in a first direction, protrudes to one side in the first direction, and has the first through hole. a first member having a cylindrical standing portion surrounding a hole; and a cylindrical member connected to the standing portion so as to communicate with the first through hole of the first member. , a second member arranged on the other side in the first direction with respect to the first member, a second member arranged between the first member and the second member, and and a joining member arranged around the first through hole when viewed in one direction, wherein the joining member is the cylindrical member, when viewed in the first direction, It is arranged outside the connection peripheral portion of the first member, which is the portion surrounding the outline of the connection portion with the standing portion. In the present composite, the joint member is arranged outside the connection peripheral portion of the first member, which is the portion surrounding the outline of the connection portion of the tubular member to the erected portion of the first member. there is Therefore, even if the connection peripheral portion of the first member is deformed due to the displacement of the tubular member, the deformation is less likely to be transmitted to the joining member. As a result, according to the present composite, it is possible to suppress damage to the joined portion by the joining member due to the displacement of the tubular member.

(2) In the above composite, the second member may be arranged so as to be adjacent to the first member on the other side in the first direction. In this composite, a joining member is arranged between a first member and an adjacent second member. Even in such a configuration in which the joint member is arranged at a position close to the deformed portion of the first member, by applying the present invention, the joint portion by the joint member is damaged due to the displacement of the tubular member. can be suppressed.

(3) In the above composite, the rigidity of the overlapping portion of the first member that overlaps with the joining member when viewed in the first direction may be higher than the rigidity of the connecting peripheral portion. According to this composite, even if the connecting peripheral portion of the first member is deformed, the overlapping portion of the first member is less likely to be deformed. Therefore, it is possible to suppress the deformation of the first member from being transmitted to the joint member, and effectively suppress damage to the joint portion by the joint member due to the displacement of the tubular member.

(4) In the above composite, the joining member is formed with a second through hole surrounding the first through hole when viewed in the first direction, and when viewed in the first direction, at least , on two imaginary straight lines extending in mutually different directions from the center of the space surrounded by the outline of the connecting portion of the cylindrical member, the distance between the connecting portion of the cylindrical member and the joining member is It is good also as a mutually different structure. According to this composite, for example, when the tubular member is displaced in the direction in which the separation distance is long, it is possible to effectively suppress damage to the joint portion by the joint member.

(5) In the above composite, the composite is an electrochemical reaction block composed of a plurality of electrochemical reaction units arranged side by side in the first direction, and each of the electrochemical reaction units is an electrolyte and an air electrode and a fuel electrode facing each other in the first direction with the electrolyte layer interposed therebetween. , is arranged on the other side in the first direction with respect to the first member, the second member is arranged between the electrochemical reaction block and the first member, and each of the A manifold for exchanging gas between a specific electrode, which is at least one of the air electrode and the fuel electrode in the electrochemical reaction unit, extends from the inside of the electrochemical reaction block to the first member of the first member. An electrochemical reaction cell stack may be formed so as to reach the cylindrical member through a through hole. In the present electrochemical reaction cell stack, the joint member is arranged outside the connecting peripheral portion, which is the portion surrounding the outline of the connecting portion with the end member, of the tubular member. Therefore, even if the connection peripheral portion of the end member is deformed due to the displacement of the tubular member due to an external force, the deformation is less likely to be transmitted to the joining member. As a result, according to the present electrochemical reaction cell stack, it is possible to suppress damage to joints by the joint members due to displacement of the cylindrical members.

The technology disclosed in this specification can be implemented in various forms. For example, an electrochemical reaction cell stack (fuel cell stack or Electrolytic cell stack), the above composites, methods for producing them, and the like.

1 is a perspective view showing the external configuration of a fuel cell stack 100 according to this embodiment; FIG. Explanatory drawing showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position II-II in FIG. Explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position III-III in FIG. Explanatory drawing showing the YZ cross-sectional configuration of the fuel cell stack 100 at the position IV-IV in FIG. Explanatory diagram showing the XZ cross-sectional configuration of two power generation units 102 adjacent to each other at the same position as the cross section shown in FIG. Explanatory diagram showing the XZ cross-sectional configuration of two power generation units 102 adjacent to each other at the same position as the cross section shown in FIG. Explanatory diagram showing the YZ cross-sectional configuration of two power generation units 102 adjacent to each other at the same position as the cross section shown in FIG. Explanatory diagram showing the XY cross-sectional configuration of the power generation unit 102 at the position of VIII-VIII in FIG. Explanatory diagram showing the XY cross-sectional configuration of the power generation unit 102 at the position of IX-IX in FIG. An explanatory diagram showing an enlarged joint structure between the lower end plate 106 and the lower terminal plate 420 Explanatory drawing showing the XY plane configuration of the gas passage member 27 and the like at the position XI-XI in FIG.

A. Embodiment:
A-1. composition:
(Configuration of fuel cell stack 100)
FIG. 1 is a perspective view showing the external configuration of the fuel cell stack 100 in this embodiment, and FIG. 2 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position II-II in FIG. 3 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position III-III in FIG. 1, and FIG. 4 is the YZ cross-sectional configuration of the fuel cell stack 100 at the position IV-IV in FIG. It is an explanatory diagram showing. Each figure shows mutually orthogonal XYZ axes for specifying directions. In this specification, for the sake of convenience, the positive Z-axis direction is referred to as the upward direction, and the negative Z-axis direction is referred to as the downward direction. may be installed. The same applies to FIG. 5 and subsequent figures. The fuel cell stack 100 is an example of a composite in the claims, and the vertical direction (Z-axis direction) is an example of the first direction in the claims.

The fuel cell stack 100 includes a plurality of (seven in this embodiment) fuel cell power generation units (hereinafter simply referred to as "power generation units") 102, terminal separators 210, upper end plates 220, lower end plates 189, and a pair of terminal plates 410, 420, an insulating portion 200, and a pair of end plates 104, 106. The seven power generation units 102 are arranged side by side in a predetermined arrangement direction (vertical direction in this embodiment). One of the pair of terminal plates 410 and 420 (hereinafter referred to as "upper terminal plate 410") is located above an assembly (hereinafter referred to as "power generation block 103") composed of seven power generation units 102. The other of the pair of terminal plates 410 , 420 (hereinafter referred to as “lower terminal plate 420 ”) is arranged below the power generation block 103 . End separator 210 is positioned above upper terminal plate 410 and lower end plate 189 is positioned below lower terminal plate 420 . The insulating portion 200 is positioned above the terminal separator 210 . One of the pair of end plates 104 and 106 (hereinafter referred to as "upper end plate 104") is arranged above the insulating portion 200, and the other of the pair of end plates 104 and 106 (hereinafter referred to as “Lower end plate 106 ”) is located below the lower end plate 189 . The pair of end plates 104 and 106 are arranged to sandwich the power generation block 103, the terminal separator 210, the lower end plate 189, the pair of terminal plates 410 and 420, and the insulating portion 200 from above and below. The power generation unit 102 is an example of an electrochemical reaction unit in the claims, and the power generation block 103 is an example of an electrochemical reaction block in the claims.

As shown in FIGS. 1 and 4, each layer (the power generation block 103, the terminal separator 210, the lower end plate 189, the pair of terminal plates 410 and 420, and the insulating portion 200) constituting the fuel cell stack 100 rotates in the Z-axis direction. Holes penetrating vertically through each layer are formed in the vicinity of four corners of the outer periphery of the . Holes (screw holes) are formed through the upper end plate 104 in the vicinity of the four corners of the outer periphery around the Z-axis direction, and the lower end plate 106 near the four corners of the outer periphery of the lower end plate 106 around the Z-axis direction. A hole (screw hole) is formed through the . Corresponding holes formed in each layer communicate with each other in the vertical direction to form bolt holes 109 extending in the vertical direction. In the following description, the holes formed in each layer of the fuel cell stack 100 to constitute the bolt holes 109 may also be referred to as the bolt holes 109 .

A bolt 22 is inserted into each bolt hole 109 . The upper end of each bolt 22 is screwed into the threaded hole of the nut 24 through the hole of the upper end plate 104, and the lower end of each bolt 22 is screwed into the nut 24 through the hole of the lower end plate 106. screwed into the screw hole. Each layer of the fuel cell stack 100 is integrally fastened by the bolts 22 and nuts 24 configured in this manner.

Further, as shown in FIGS. 1 to 3, each layer (each power generation unit 102, lower terminal plate 420, lower end plate 189, lower end plate 106) constituting the fuel cell stack 100 has peripheral edges around the Z-axis direction. is formed with four holes vertically penetrating each layer, and the corresponding holes formed in each layer communicate with each other in the vertical direction, extending vertically from the uppermost power generation unit 102 to the lower end plate 106 A communication hole 108 extending in the direction is formed. In the following description, the holes formed in each layer of the fuel cell stack 100 to form the communication holes 108 may also be referred to as the communication holes 108 . Hereinafter, among the communication holes 108 , the holes formed in the lower end plate 106 are particularly referred to as end through holes 107 .

As shown in FIGS. 1 and 2, in the vicinity of one side (one of the two sides parallel to the Y-axis, the side on the positive side of the X-axis) that constitutes the outer circumference of the fuel cell stack 100 around the Z-axis direction. One communication hole 108 is a gas flow path through which an oxidant gas OG is introduced from the outside of the fuel cell stack 100 and supplies the oxidant gas OG to an air chamber 166 of each power generation unit 102, which will be described later. One communication hole 108 that functions as a gas supply manifold 161 and is located near the side opposite to the side (the side on the negative side of the X axis among the two sides parallel to the Y axis) is connected to each power generation unit. It functions as an oxidant gas discharge manifold 162 that is a gas flow path for discharging the oxidant offgas OOG, which is the gas discharged from the air chamber 166 of the fuel cell stack 102 , to the outside of the fuel cell stack 100 . The oxidant gas supply manifold 161 and the oxidant gas discharge manifold 162 are gas flow paths for exchanging gas with the air electrode 114 (described later) of each power generation unit 102 . For example, air is used as the oxidant gas OG.

1 and 3, among the sides forming the outer circumference of the fuel cell stack 100 around the Z-axis direction, the vicinity of the side closest to the communication hole 108 functioning as the oxidant gas discharge manifold 162 described above. Another communication hole 108 located in the fuel cell stack 100 is a gas flow path for introducing the fuel gas FG from the outside of the fuel cell stack 100 and supplying the fuel gas FG to a fuel chamber 176 of each power generation unit 102, which will be described later. Another communication hole 108 located near the side closest to the communication hole 108 functioning as the gas supply manifold 171 and functioning as the oxidant gas supply manifold 161 described above discharges from the fuel chamber 176 of each power generation unit 102. It functions as a fuel gas discharge manifold 172 that is a gas flow path for discharging the fuel off-gas FOG, which is the gas that has been discharged, to the outside of the fuel cell stack 100 . The fuel gas supply manifold 171 and the fuel gas discharge manifold 172 are gas flow paths for exchanging gas with the fuel electrode 116 (described later) of each power generation unit 102 . As the fuel gas FG, for example, a hydrogen-rich gas obtained by reforming city gas is used. Also, hereinafter, the air chamber 166 and the fuel chamber 176 are collectively referred to as a "gas chamber".

As shown in FIGS. 1 to 3, the fuel cell stack 100 is provided with four gas passage members 27 . Each gas passage member 27 is made of a conductive material (metallic material) such as ferritic stainless steel containing aluminum, and has a hollow cylindrical body portion 28 and a flange portion 29 . A gas through hole 26 is formed in the body portion 28 so as to penetrate vertically. One end (upper end) of the body portion 28 is connected to an end through hole 107 formed in the lower end plate 106 . Specifically, the upper end of the body portion 28 is inserted into the end through hole 107 and joined by welding, for example. The outer diameter and inner diameter of the upper end of the body portion 28 are smaller than the outer diameter and inner diameter of the other end (lower end) of the body portion 28 . The plate thickness (difference between the outer diameter and the inner diameter) of the body portion 28 can be, for example, 0.6 mm or more and 1.0 mm or less. The flange portion 29 is provided so as to protrude from the lower end side of the main body portion 28 in a surface direction (direction parallel to the XY plane) perpendicular to the vertical direction (Z-axis direction). The shape of the flange portion 29 when viewed in the vertical direction is substantially rectangular, and bolt holes 29A (see FIG. 1) are formed at each of the four corners. A bolt (not shown) for connecting the fuel cell stack 100 to an external device is inserted into each bolt hole 29A.

As shown in FIG. 2, the gas through-hole 26 of the gas passage member 27 arranged at the position of the oxidant gas supply manifold 161 communicates with the oxidant gas supply manifold 161, and is located at the position of the oxidant gas discharge manifold 162. The gas through-holes 26 of the gas passage member 27 arranged at 1 are in communication with the oxidizing gas discharge manifold 162 . Further, as shown in FIG. 3, the gas through hole 26 of the gas passage member 27 arranged at the position of the fuel gas supply manifold 171 communicates with the fuel gas supply manifold 171, and at the position of the fuel gas discharge manifold 172. The gas through holes 26 of the arranged gas passage member 27 communicate with the fuel gas discharge manifold 172 .

(Configuration of end plates 104, 106)
The pair of end plates 104 and 106 is a plate-like member having a substantially rectangular outer shape when viewed in the Z-axis direction, and is made of a conductive material (metal material) such as ferritic stainless steel on which an oxide film of alumina is formed. It is Holes 32 and 34 penetrating in the Z-axis direction are formed near the center of the pair of end plates 104 and 106, respectively. As viewed in the Z-axis direction, the inner peripheral lines of the holes 32, 34 formed in the pair of end plates 104, 106 respectively include at least a portion of each single cell 110, which will be described later. A compressive force in the Z-axis direction generated by fastening with each bolt 22 and nut 24 acts mainly on the peripheral edge portion of each power generation unit 102 (portion on the outer peripheral side from each unit cell 110 described later). The end plates 104 and 106 are each formed by pressing (bending) a single plate member. The plate thickness of the end plates 104 and 106 can be, for example, 1 mm or more and 3 mm or less, and is the same as the plate thickness of the main body portion 28 of the gas passage member 27 or thinner than the plate thickness of the main body portion 28 of the gas passage member 27. may

As shown in FIGS. 2-4, the upper end plate 104 includes a planar portion 310 and a convex portion 320. As shown in FIG. The plane portion 310 is a flat portion along a surface direction (direction parallel to the XY plane) perpendicular to the Z-axis direction. Specifically, the shape of the planar portion 310 as viewed in the Z-axis direction is a rectangular frame shape as a whole. The holes forming the bolt holes 109 described above are formed in the peripheral edge portion of the flat portion 310 around the Z-axis direction. The convex portion 320 is a rib that protrudes upward from the flat portion 310 . The protrusion 320 has an outer protrusion 322 and an inner protrusion 324 . The outer convex portion 322 protrudes upward from the outer peripheral portion of the planar portion 310 . Outer convex portion 322 is formed along the entire circumference of the outer peripheral portion of flat portion 310 . The inner convex portion 324 protrudes upward from the inner peripheral portion of the flat portion 310 . The inner convex portion 324 is formed along the entire circumference of the inner peripheral portion of the planar portion 310 .

Also, the lower end plate 106 includes a flat portion 510 and a convex portion 520 . The plane portion 510 is a flat portion along a plane direction (direction parallel to the XY plane) perpendicular to the Z-axis direction. Specifically, the shape of the planar portion 510 as viewed in the Z-axis direction is a rectangular frame shape as a whole. In addition, the holes forming the bolt holes 109 described above are formed in the peripheral portion of the plane portion 510 around the Z-axis direction. The convex portion 520 is a rib projecting downward from the flat portion 510 . The convex portion 520 has an outer convex portion 522 and an inner convex portion 524 . The outer convex portion 522 protrudes downward from the outer peripheral portion of the flat portion 510 . Outer convex portion 522 is formed along the entire circumference of the outer peripheral portion of flat portion 510 . The inner convex portion 524 protrudes downward from the inner peripheral portion of the planar portion 510 . The inner convex portion 524 is formed along the entire circumference of the inner peripheral portion of the planar portion 510 .

As shown in FIGS. 2 and 3, a reinforcing member 600 is fixed to the lower end plate 106 . The reinforcing member 600 has a flat plate portion 610 and a tubular portion 620 . The flat plate portion 610 is a flat plate-like portion parallel to the flat portion 510 of the lower end plate 106 . The shape of the flat plate portion 610 when viewed in the up-down direction is substantially rectangular. The flat plate portion 610 is positioned at a position spaced downward from the flat portion 510 of the lower end plate 106 . One side in the longitudinal direction of the flat plate portion 610 is in contact with the inner wall surface of the outer convex portion 522 and is joined by, for example, welding. It contacts the inner wall surface and is joined by welding, for example. A through hole 612 into which the main body portion 28 of the gas passage member 27 can be inserted is formed in the flat plate portion 610 . The tubular portion 620 is a cylindrical portion having a through hole 622 communicating with the through hole 612 of the flat plate portion 610 . Cylindrical portion 620 is formed to protrude downward from the peripheral portion of through hole 612 in flat plate portion 610 . The inner wall surfaces forming the through hole 612 of the flat plate portion 610 and the through hole 622 of the cylindrical portion 620 are in contact with the outer peripheral surface of the main body portion 28 of the gas passage member 27 and are joined by welding, for example. The flat plate portion 610 and the tubular portion 620 are integrally formed. The reinforcing member 600 is preferably made of a heat-resistant material, the same material as the lower end plate 106, the gas passage member 27, or the like, or a material having the same coefficient of thermal expansion. It is

(Configuration of Terminal Plates 410, 420)
The pair of terminal plates 410 and 420 are plate-like members having a substantially rectangular outer shape when viewed in the Z-axis direction, and are made of a conductive material such as ferritic stainless steel on which an oxide film of alumina is formed, for example. A hole 412 is formed near the center of the upper terminal plate 410 so as to penetrate in the Z-axis direction. As viewed in the Z-axis direction, the inner peripheral line of the hole 412 formed in the upper terminal plate 410 includes each single cell 110 described later. As viewed in the Z-axis direction, one end (positive X-axis direction side) of each of the pair of terminal plates 410 and 420 protrudes laterally from the power generation block 103 . In this embodiment, the projecting portion of the upper terminal plate 410 functions as a positive output terminal of the fuel cell stack 100 , and the projecting portion of the lower terminal plate 420 functions as a negative output terminal of the fuel cell stack 100 . do.

(Configuration of upper end plate 220)
The upper end plate 220 is a plate-like member having a substantially rectangular outer shape when viewed in the Z-axis direction, and is made of a conductive material such as stainless steel. The upper end plate 220 is arranged above the power generation block 103 and is electrically connected to an interconnector 190 (described later) located at the upper end of the power generation block 103 . In this embodiment, the upper end plate 220 and the interconnector 190 are electrically connected via a connecting member having the same structure as the fuel electrode side collector member 144 described later.

(Structure of Terminal Separator 210)
The terminal separator 210 is a frame-shaped member having a substantially rectangular through-hole 211 penetrating vertically in the vicinity of the center thereof, and is made of metal, for example. A portion of the terminal separator 210 surrounding the through hole 211 (hereinafter referred to as a “through hole surrounding portion”) is joined to the upper surface of the peripheral portion of the upper end plate 220 by, for example, welding. The end separator 210 separates the space between the top plate 220 and the power generation block 103 and the space outside the fuel cell stack 100 .

The terminal separator 210 includes an inner portion 216 including the peripheral portion of the through hole of the terminal separator 210, an outer portion 217 located on the outer peripheral side of the inner portion 216, and a connecting portion 218 connecting the inner portion 216 and the outer portion 217. Prepare. In this embodiment, the inner portion 216 and the outer portion 217 are substantially flat plates extending in a direction substantially orthogonal to the Z-axis direction. Further, the connecting portion 218 has a curved shape that protrudes downward from both the inner portion 216 and the outer portion 217 . A lower portion (on the power generation block 103 side) of the connecting portion 218 is a convex portion, and an upper portion (on the upper end plate 104 side) of the connecting portion 218 is a concave portion. Therefore, the connecting portion 218 includes portions whose positions in the Z-axis direction are different from those of the inner portion 216 and the outer portion 217 .

(Configuration of lower end plate 189)
The lower end plate 189 is a flat member having a substantially rectangular outer shape when viewed in the Z-axis direction, and is made of an insulating material, for example. The peripheral edge of the lower end plate 189 is sandwiched between the lower terminal plate 420 and the lower end plate 106, thereby ensuring insulation between the lower terminal plate 420 and the lower end plate 106. ing.

(Configuration of insulating portion 200)
The insulating portion 200 is a frame-shaped member having a substantially rectangular through hole penetrating vertically in the vicinity of the center thereof, and is made of, for example, an insulating material. The insulating portion 200 is sandwiched between the upper end plate 104 and the terminal separator 210 to provide sealing for each manifold 161 , 162 , 171 , 172 and insulation between the upper end plate 104 and the terminal separator 210 . is guaranteed.

(Configuration of power generation unit 102)
5 is an explanatory diagram showing the XZ cross-sectional configuration of two power generation units 102 adjacent to each other at the same position as the cross section shown in FIG. 2, and FIG. FIG. 7 is an explanatory diagram showing the XZ cross-sectional configuration of two power generation units 102, and FIG. 7 is an explanatory diagram showing the YZ cross-sectional configuration of two adjacent power generation units 102 at the same position as the cross section shown in FIG. 8 is an explanatory diagram showing the XY cross-sectional configuration of the power generation unit 102 at the position VIII-VIII in FIG. 5, and FIG. 9 is the XY cross-sectional configuration of the power generation unit 102 at the position IX-IX in FIG. It is an explanatory diagram showing.

As shown in FIGS. 5 to 7, the power generation unit 102 includes a fuel cell single cell (hereinafter referred to as "single cell") 110, a single cell separator 120, an air electrode side frame 130, and a fuel electrode side frame. 140 , a fuel electrode side collector member 144 , and a pair of interconnectors 190 and a pair of IC separators 180 that constitute the uppermost and lowermost layers of the power generation unit 102 . Communicating holes 108 functioning as manifolds 161, 162, 171, and 172 are formed in peripheral portions of the single cell separator 120, the air electrode side frame 130, the fuel electrode side frame 140, and the IC separator 180 around the Z-axis direction. Constituting holes and holes constituting each bolt hole 109 are formed.

The single cell 110 includes an electrolyte layer 112, an air electrode 114 arranged on one side (upper side) of the electrolyte layer 112 in the Z-axis direction, and an air electrode 114 arranged on the other side (lower side) of the electrolyte layer 112 in the Z-axis direction. It comprises an anode 116 and a reaction prevention layer 118 disposed between the electrolyte layer 112 and the cathode 114 . The single cell 110 of this embodiment is a fuel electrode supporting type single cell in which the fuel electrode 116 supports the other layers (electrolyte layer 112, air electrode 114, reaction prevention layer 118) that constitute the single cell 110. . The single cell 110 is an example of an electrochemical reaction single cell in the claims.

The electrolyte layer 112 is a substantially rectangular plate-shaped member when viewed in the Z-axis direction, and is configured to contain a solid oxide (for example, YSZ (yttria-stabilized zirconia)). That is, the single cell 110 of this embodiment is a solid oxide fuel cell (SOFC) using a solid oxide as an electrolyte. The air electrode 114 is a substantially rectangular plate-shaped member smaller than the electrolyte layer 112 when viewed in the Z-axis direction, and is configured to contain, for example, a perovskite oxide (for example, LSCF (lanthanum strontium cobalt iron oxide)). . The fuel electrode 116 is a substantially rectangular plate-shaped member having substantially the same size as the electrolyte layer 112 when viewed in the Z-axis direction, and is formed of, for example, Ni (nickel), a cermet made of Ni and ceramic particles, a Ni-based alloy, or the like. ing. The reaction prevention layer 118 is a substantially rectangular plate-shaped member having substantially the same size as the air electrode 114 when viewed in the Z-axis direction, and is configured to contain, for example, GDC (gadolinium-doped ceria). The reaction prevention layer 118 is formed by reacting an element (eg, Sr) diffused from the air electrode 114 with an element (eg, Zr) contained in the electrolyte layer 112 to generate a high-resistance substance (eg, SrZrO ₃ ). has the function of suppressing The air electrode 114 and the fuel electrode 116 are examples of specific electrodes in the claims.

The single-cell separator 120 is a frame-shaped member having a substantially rectangular through-hole 121 penetrating vertically in the vicinity of the center thereof, and is made of metal, for example. A portion of the single-cell separator 120 surrounding the through-hole 121 (hereinafter referred to as a “through-hole surrounding portion”) faces the upper surface of the peripheral portion of the single-cell 110 (electrolyte layer 112 ). The unit cell separator 120 is joined to the unit cell 110 (electrolyte layer 112) by a joining portion 124 formed of brazing material (for example, Ag brazing) arranged at the opposing portion. An air chamber 166 facing the air electrode 114 and a fuel chamber 176 facing the fuel electrode 116 are partitioned by the single cell separator 120, and gas flows from one electrode side to the other electrode side in the peripheral portion of the single cell 110. leak (cross leak) is suppressed.

The single cell separator 120 has an inner portion 126 including the peripheral portion of the through hole of the single cell separator 120, an outer portion 127 located outside the inner portion 126, and a connection connecting the inner portion 126 and the outer portion 127. and a portion 128 . In this embodiment, the inner portion 126 and the outer portion 127 are substantially flat plates extending in a direction substantially orthogonal to the Z-axis direction. Moreover, the connecting portion 128 has a curved shape that protrudes downward from both the inner portion 126 and the outer portion 127 . The lower side (fuel chamber 176 side) of connecting portion 128 is a convex portion, and the upper side (air chamber 166 side) portion of connecting portion 128 is a concave portion. Therefore, the connecting portion 128 includes portions whose positions in the Z-axis direction are different from those of the inner portion 126 and the outer portion 127 .

A glass seal portion 125 containing glass is arranged near the through hole 121 in the single cell separator 120 . The glass seal portion 125 is positioned on the air chamber 166 side with respect to the joint portion 124, and the surface of the unit cell separator 120 around the through hole and the surface of the unit cell 110 (the electrolyte layer 112 in this embodiment) is formed to contact both the The glass seal portion 125 effectively suppresses gas leak (cross leak) from one electrode side to the other electrode side in the peripheral portion of the unit cell 110 .

The interconnector 190 is a conductive member having a substantially rectangular flat plate-shaped flat plate portion 150 and a plurality of substantially columnar air electrode side current collectors 134 projecting from the flat plate portion 150 toward the air electrode 114 side. (for example, ferritic stainless steel). In this embodiment, the surface of the interconnector 190 (the surface facing the air chamber 166) is formed with a conductive coating layer 194 made of, for example, spinel oxide. Below, the interconnector 190 covered with the covering layer 194 is simply referred to as the interconnector 190 . The interconnector 190 (each air electrode-side current collector 134 thereof) is joined to the air electrode 114 of the unit cell 110 via a conductive joint material 196 made of, for example, spinel oxide. It is electrically connected to the cathode 114 of the cell 110 . The interconnector 190 ensures electrical continuity between the power generation units 102 and suppresses mixing of reaction gases between the power generation units 102 . In addition, in this embodiment, when two power generation units 102 are arranged adjacently, one interconnector 190 is shared by the two adjacent power generation units 102 . That is, the upper interconnector 190 in one power generation unit 102 is the same member as the lower interconnector 190 in another power generation unit 102 adjacent to the upper side of the power generation unit 102 . In addition, since the fuel cell stack 100 has the lower terminal plate 420 and the lower end plate 189, the lowermost power generation unit 102 in the fuel cell stack 100 does not have the lower interconnector 190 (FIG. 2). to Figure 4).

The IC separator 180 is a frame-shaped member having a substantially rectangular through-hole 181 extending vertically through the vicinity of the center thereof, and is made of metal, for example. A portion of the IC separator 180 surrounding the through-hole 181 (hereinafter referred to as “through-hole surrounding portion”) is joined to the upper surface of the periphery of the flat plate portion 150 of the interconnector 190 by, for example, welding. Among the pair of IC separators 180 included in a certain power generation unit 102, the upper IC separator 180 is connected to the air chamber 166 of the power generation unit 102 and the other power generation unit 102 adjacent to the power generation unit 102 on the upper side. and the fuel chamber 176 of the . Also, of the pair of IC separators 180 included in a certain power generation unit 102, the lower IC separator 180 is adjacent to the fuel chamber 176 of the power generation unit 102 and the power generation unit 102 on the lower side. and the air chamber 166 of the power generation unit 102 . In this manner, the IC separator 180 suppresses gas leakage between the power generation units 102 at the periphery of the power generation units 102 . Note that the IC separator 180 joined to the upper interconnector 190 of the power generation unit 102 located at the uppermost position in the fuel cell stack 100 is electrically connected to the upper terminal plate 410 .

The IC separator 180 has an inner portion 186 including the peripheral portion of the through hole of the IC separator 180, an outer portion 187 located outside the inner portion 186, and a connecting portion 188 connecting the inner portion 186 and the outer portion 187. and In this embodiment, the inner portion 186 and the outer portion 187 are substantially flat plates extending in a direction substantially orthogonal to the Z-axis direction. Moreover, the connecting portion 188 has a curved shape that protrudes downward from both the inner portion 186 and the outer portion 187 . The lower side (air chamber 166 side) of the connecting portion 188 is a convex portion, and the upper side (fuel chamber 176 side) portion of the connecting portion 188 is a concave portion. Therefore, the connecting portion 188 includes portions whose positions in the Z-axis direction are different from those of the inner portion 186 and the outer portion 187 .

As shown in FIG. 8, the air electrode side frame 130 is a frame-shaped member having a substantially rectangular hole 131 extending in the Z-axis direction near the center, and is made of an insulator such as mica. there is A hole 131 in the cathode-side frame 130 constitutes an air chamber 166 facing the cathode 114 . The air electrode side frame 130 is in contact with the upper surface of the periphery of the single cell separator 120 and the lower surface of the periphery of the upper IC separator 180, and the gas sealing property ( That is, it functions as a sealing member that secures the gas sealing property of the air chamber 166 . Also, the cathode-side frame 130 electrically insulates between the pair of IC separators 180 included in the power generation unit 102 (that is, between the pair of interconnectors 190). The air electrode side frame 130 also has an oxidizing gas supply communication hole 132 that communicates the oxidizing gas supply manifold 161 and the air chamber 166, and an oxidizing gas supply communication hole 132 that communicates the air chamber 166 and the oxidizing gas discharge manifold 162. A discharge communication hole 133 is formed.

As shown in FIG. 9, the fuel electrode-side frame 140 is a frame-shaped member having a substantially rectangular hole 141 penetrating in the Z-axis direction near the center, and is made of metal, for example. A hole 141 in the anode-side frame 140 constitutes a fuel chamber 176 facing the anode 116 . The fuel electrode-side frame 140 is in contact with the lower surface of the periphery of the single cell separator 120 and the upper surface of the periphery of the lower IC separator 180 . Further, the fuel electrode side frame 140 has a fuel gas supply communication hole 142 that communicates the fuel gas supply manifold 171 and the fuel chamber 176, and a fuel gas discharge communication hole 143 that communicates the fuel chamber 176 and the fuel gas discharge manifold 172. and are formed.

As shown in FIGS. 5 to 7 , the fuel electrode side collector member 144 is arranged inside the fuel chamber 176 . The fuel electrode-side current collecting member 144 includes an interconnector-facing portion 146, an electrode-facing portion 145, and a connecting portion 147 that connects the electrode-facing portion 145 and the interconnector-facing portion 146, and is made of, for example, nickel or a nickel alloy. , stainless steel or the like. The electrode facing portion 145 is in contact with the lower surface of the fuel electrode 116 , and the interconnector facing portion 146 is in contact with the upper surface of (the flat plate portion 150 of) the interconnector 190 . However, as described above, since the lowermost power generation unit 102 in the fuel cell stack 100 does not have the lower interconnector 190, the fuel electrode side current collecting member 144 of the power generation unit 102 faces the interconnector. Portion 146 contacts lower terminal plate 420 . Fuel electrode side current collecting member 144 having such a configuration electrically connects fuel electrode 116 and interconnector 190 (or lower end plate 189). A spacer 149 made of mica, for example, is arranged between the electrode facing portion 145 and the interconnector facing portion 146 of the fuel electrode side collector member 144 . Therefore, the fuel electrode side current collecting member 144 follows the deformation of the power generation unit 102 due to the temperature cycle and reaction gas pressure fluctuation, and the fuel electrode 116 and the interconnector 190 (or the lower terminal plate) via the fuel electrode side current collecting member 144. 420) is well maintained. The fuel electrode side collector member 144 is, for example, a sheet-shaped material (for example, a nickel foil with a thickness of 10 to 200 μm) with a plurality of rectangular cuts and a plurality of holes formed on the material. In the state where the fuel electrode side current collecting member 144 is arranged, a plurality of rectangular portions are bent and processed so as to sandwich the spacer 149 . Each bent rectangular portion becomes an electrode facing portion 145, and a flat plate portion with a hole other than the bent and raised portion becomes an interconnector facing portion 146, which connects the electrode facing portion 145 and the interconnector facing portion 146. A portion becomes the connecting portion 147 .

A-2. Operation of fuel cell stack 100:
As shown in FIGS. 2 and 5, the oxidant gas OG is supplied through a gas pipe (not shown) connected to the body portion 28 of the gas passage member 27 provided at the position of the oxidant gas supply manifold 161. Then, the oxidizing gas OG is supplied to the oxidizing gas supply manifold 161 through the gas through holes 26 of the gas passage member 27, and from the oxidizing gas supply manifold 161 to the oxidizing gas supply communication holes of each power generation unit 102. 132 to air chamber 166 . 3 and 6, the fuel gas FG is supplied through a gas pipe (not shown) connected to the body portion 28 of the gas passage member 27 provided at the position of the fuel gas supply manifold 171. Then, the fuel gas FG is supplied to the fuel gas supply manifold 171 through the gas through hole 26 of the gas passage member 27, and from the fuel gas supply manifold 171 through the fuel gas supply communication hole 142 of each power generation unit 102. , are supplied to the fuel chamber 176 .

When the oxidant gas OG is supplied to the air chamber 166 of each power generation unit 102 and the fuel gas FG is supplied to the fuel chamber 176, electric power is generated in the single cell 110 by the electrochemical reaction of the oxidant gas OG and the fuel gas FG. will be This power generation reaction is an exothermic reaction. In each power generation unit 102, the air electrode 114 of the unit cell 110 is electrically connected to the upper interconnector 190, and the fuel electrode 116 is connected to the lower interconnector 190 (or the lower plate 189). That is, the plurality of power generation units 102 included in the fuel cell stack 100 are electrically connected in series. The upper interconnector 190 and the IC separator 180 of the uppermost power generation unit 102 are electrically connected to the upper terminal plate 410, and the lowermost power generation unit 102 is connected to the fuel electrode side. A lower terminal plate 420 is electrically connected to the electrical member 144 . Therefore, the electrical energy generated in each power generation unit 102 is taken out from terminal plates 410 and 420 that function as output terminals of fuel cell stack 100 . Since the SOFC generates power at a relatively high temperature (for example, 600° C. to 1000° C.), the fuel cell stack 100 is heated by the heater ( (not shown).

As shown in FIGS. 2 and 5, the oxidant off-gas OOG discharged from the air chamber 166 of each power generation unit 102 to the oxidant gas discharge manifold 162 through the oxidant gas discharge communication hole 133 is discharged into the oxidant gas discharge manifold. The gas is discharged to the outside of the fuel cell stack 100 via a gas pipe (not shown) connected to the main body 28 through the gas through hole 26 of the main body 28 of the gas passage member 27 provided at the position 162. be. Further, as shown in FIGS. 3 and 6, the fuel off-gas FOG discharged from the fuel chamber 176 of each power generation unit 102 to the fuel gas discharge manifold 172 through the fuel gas discharge communication hole 143 is The gas is discharged to the outside of the fuel cell stack 100 via a gas pipe (not shown) connected to the main body 28 through the gas through hole 26 of the main body 28 of the gas passage member 27 provided at the position.

In the fuel cell stack 100 of the present embodiment, in each power generation unit 102, the main flow direction of the oxidant gas OG in the air chamber 166 (the direction from the positive direction of the X axis to the negative direction of the X axis) This is a counter-flow type SOFC in which the main flow direction of the gas FG (the direction from the negative direction of the X axis to the positive direction of the X axis) is substantially opposite (directions facing each other).

A-3. Joint structure between lower end plate 106 and lower terminal plate 420:
Next, a joint structure between the lower end plate 106 and the lower terminal plate 420 in the fuel cell stack 100 of this embodiment will be described. 10 is an enlarged explanatory view showing the joint structure between the lower end plate 106 and the lower terminal plate 420, and FIG. 11 is an XY plane of the gas passage member 27, etc., at the position XI-XI in FIG. It is an explanatory view showing a configuration. FIG. 11 illustrates the gas passage member 27 communicating with the oxidant gas supply manifold 161 . In FIG. 11, the gas passage member 27 and the lower end plate 106 are indicated by solid lines, and the glass seal member 197, communication hole 108, etc. located behind the lower end plate 106 are indicated by dotted lines.

As shown in FIGS. 2 to 4, 10 and 11, the lower end plate 106 of this embodiment has four standing portions 530 formed therein. The standing portion 530 has a tubular shape that protrudes downward (Z-axis negative direction side) from the flat portion 510 of the lower end plate 106 and surrounds the end through hole 107 of the lower end plate 106 when viewed in the vertical direction. . The standing portion 530 is formed integrally with the flat portion 510 . In this embodiment, the inner wall surface defining the end through-hole 107 of the lower end plate 106 and the inner peripheral wall of the standing portion 530 are flush with each other without a step. The lower end plate 106 is an example of a first member in the scope of claims, and the end through-hole 107 is an example of a first through-hole in the scope of claims.

The gas passage member 27 is connected to the standing portion 530 of the lower end plate 106 , and the gas passage of the gas passage member 27 communicates with the end through hole 107 of the lower end plate 106 . Specifically, the tip portion 28a of the gas passage member 27 is inserted into the inner peripheral side of the standing portion 530, and the tip portion 28a of the gas passage member 27 and the standing portion 530 are joined by welding or the like. ing. The gas passage member 27 is an example of a tubular member in the claims.

A glass sealing member 197 made of glass is arranged between the lower end plate 106 and the lower terminal plate 420 . The glass seal member 197 is arranged in a frame shape around the communication hole 108 (hereinafter referred to as "block communication hole 108B") formed in the power generation block 103 when viewed from above. The glass seal member 197 is a member that joins vertically adjacent members (the lower end plate 106 and the lower terminal plate 420). The thickness of the glass seal member 197 can be, for example, 1.0 mm or more and 1.5 mm or less. The glass seal member 197 is an example of a joining member in the scope of claims, and the lower terminal plate 420 is an example of a second member in the scope of claims.

As shown in FIG. 11, the glass seal member 197 is arranged outside the connection peripheral portion 520b of the lower end plate 106 when viewed in the vertical direction. The connection peripheral portion 520b corresponds to the outline of the portion of the lower end plate 106 (flat portion 510) that is connected to the standing portion 530 of the gas passage member 27 when viewed in the vertical direction (in FIG. It is a portion surrounding the contour line of the tip portion 28 a of the main body portion 28 . Specifically, the glass seal member 197 is a frame-shaped member in which an insertion hole 197a is formed. Surrounding. The difference between the inner diameter and the outer diameter of the glass seal member 197 can be, for example, 2 mm or more and 4 mm or less. The outline of the insertion hole 197a is positioned outside the connection peripheral portion 520b of the lower end plate 106 over the entire circumference when viewed from the top-bottom direction. The through hole 197a is an example of a second through hole in the claims.

Reference character O in FIG. 11 indicates the center of the space surrounded by the outline of the connection portion (tip portion 28a) of the gas passage member 27 (hereinafter referred to as "the center O of the connection portion"). As viewed in the vertical direction, the separation distance between the connection portion of the gas passage member 27 and the glass seal member 197 is different at least on two imaginary straight lines L1 and L2 extending in mutually different directions from the center O of the connection portion. . Specifically, as shown in FIG. 11, a first separation distance between the connecting portion and the glass seal member 197 on a first imaginary straight line L1 (an imaginary straight line extending in the Y-axis negative direction from the center O of the connecting portion). D1 is different from a second separation distance D2 between the connecting portion and the glass seal member 197 on the second imaginary straight line L2 (an imaginary straight line extending from the center O of the connecting portion in the positive direction of the Y-axis). In other words, in this embodiment, the two separation distances D1 and D2 between the connecting portion and the glass seal member 197 existing on one imaginary straight line L1 (L2) passing through the center O are different from each other.

More specifically, of the block communication holes 108B of the power generation block 103, the block communication holes 108B forming the oxidant gas supply manifold 161 are long holes extending in a predetermined direction (Y-axis direction). As viewed in the vertical direction, the end through-hole 107 (upright portion 530) of the lower end plate 106 is arranged at a position (positive Y-axis direction) deviated in the predetermined direction within the outline of the block communication hole 108B. ing. The insertion hole 197a of the glass seal member 197 is an elongated hole that is slightly larger than the block communication hole 108B, and the outline of the insertion hole 197a surrounds the block communication hole 108B. With such a configuration, the first separation distance D1 is longer than the second separation distance D2.

In the present embodiment, among the block communication holes 108B of the power generation block 103, the block communication holes 108B forming the oxidant gas discharge manifold 162 are also long holes extending in a predetermined direction (Y-axis direction) (see FIG. 8, etc.). reference). For this reason, the glass seal member 197 arranged so as to communicate with the oxidizing gas discharge manifold 162 is likewise located on one imaginary straight line passing through the center of the connecting portion of the gas passage member 27 and the connecting portion. are different from each other. On the other hand, the block communication holes 108B forming the fuel gas supply manifold 171 and the fuel gas discharge manifold 172, respectively, are circular holes (see FIG. 8, etc.). In this embodiment, the center of the glass seal member 197 arranged so as to communicate with these manifolds 171 and 172 is arranged so as to substantially coincide with the center of the connection portion of the gas passage member 27. 27 and the glass seal member 197 are substantially uniform over the entire circumference.

In the lower end plate 106, the rigidity of the overlapping portion 510a that overlaps with the glass seal member 197 is higher than the rigidity of the connecting peripheral portion 520b when viewed in the vertical direction. Specifically, as shown in FIG. 10 , a reinforcing portion 523 is provided on the lower surface of the planar portion 510 of the lower end plate 106 . The reinforcing portion 523 is made of metal, for example, and is joined to the lower surface of the planar portion 510 . The reinforcing portion 523 is formed so as to surround the connection peripheral portion 520b of the lower end plate 106 when viewed in the vertical direction. The reinforcing portion 523 is preferably made of a heat-resistant material, the same material as the lower end plate 106, the gas passage member 27, or the like, or a material having the same coefficient of thermal expansion. formed by

A-4. Effect of this embodiment:
As described above, the fuel cell stack 100 of the present embodiment is arranged outside the connecting peripheral portion 520b of the lower end plate 106 when viewed in the vertical direction (see FIGS. 10 and 11). Therefore, even if the connecting peripheral portion 520 b of the lower end plate 106 deforms due to the displacement of the gas passage member 27 , the deformation is less likely to be transmitted to the glass seal member 197 . As a result, according to the present embodiment, it is possible to suppress damage to the joint portion by the glass seal member 197 due to the displacement of the gas passage member 27 . The displacement of the gas passage member 27 is, for example, the movement of the standing portion 530 in the axial direction (Z-axis direction) or the inclination of the base end side (lower end side) of the gas passage member 27 with respect to the axial direction. Factors that cause the displacement of the gas passage member 27 are, for example, stress caused by a difference in thermal expansion between the gas passage member 27 and the lower end plate 106 or the like, and external force on the gas passage member 27 .

In this embodiment, a glass seal member 197 is positioned between the lower end plate 106 and the adjacent lower terminal plate 420 (see FIG. 10). Even if the glass seal member 197 is arranged at a position close to the deformed portion of the lower end plate 106 as described above, by applying the present invention, the displacement of the gas passage member 27 causes the glass seal member to be deformed. Damage to joints due to 197 can be suppressed.

In the present embodiment, of the lower end plate 106, the rigidity of the overlapping portion 510a that overlaps with the glass seal member 197 is higher than the rigidity of the connecting peripheral portion 520b (see FIG. 10). Therefore, even if the connecting peripheral portion 520b of the lower end plate 106 is deformed, the overlapping portion 510a of the lower end plate 106 is less likely to be deformed. This suppresses the deformation of the lower end plate 106 from being transmitted to the glass seal member 197, effectively suppressing damage to the joint portion by the glass seal member 197 due to the displacement of the gas passage member 27. can be done.

In this embodiment, when viewed in the vertical direction, at least on two imaginary straight lines L1 and L2 extending in mutually different directions from the center O of the connecting portion, the distance between the connecting portion of the gas passage member 27 and the glass seal member 197 is are different from each other (see FIG. 11). According to the present embodiment, for example, when the gas passage member 27 is displaced in a direction that deforms the connection peripheral portion 520b on the side of the longer separation distance (the first separation distance D1), the joining portion by the glass seal member 197 damage can be effectively suppressed. In this embodiment, as shown in FIG. 11, the end through-hole 107 of the lower end plate 106 is arranged at a position offset from the block communication hole 108B formed in the lower terminal plate 420 (power generation block 103). It is Therefore, of the lower end plate 106 (flat portion 510), the portion on the side of the first separation distance D1 is more likely to deform than the portion on the side of the second separation distance D2. On the other hand, in the present embodiment, the first separation distance D1 is longer than the second separation distance D2. It is possible to effectively suppress damage to the joint portion by the glass seal member 197 when the glass seal member 197 is displaced.

B. Variant:
The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified in various forms without departing from the scope of the invention. For example, the following modifications are possible.

The configuration of the fuel cell stack 100 and the power generation unit 102 in the above embodiment is merely an example, and various modifications are possible.

In the above-described embodiment, the inner wall surface of the lower end plate 106 that defines the communication hole 108 and the inner peripheral wall of the standing portion 530 are flush with each other without a step. Alternatively, the inner peripheral wall of the standing portion 530 may be located outside the inner wall surface defining the communication hole 108 when viewed in the vertical direction. In the above-described embodiment, as the first through-hole, the circular or long hole-shaped communicating hole 108 formed in the lower end plate 106 was exemplified. It's okay.

In the above-described embodiment, the upright portion 530 of the lower end plate 106 is inserted into the tip portion 28a of the gas passage member 27, or the lower end surface of the upright portion 530 and the upper end surface of the gas passage member 27 abut each other. A mated and joined configuration is also possible. In the above embodiment, the gas passage member 27 in which the gas flow passage is formed was exemplified as an example of the tubular member, but the present invention is not limited to this, as long as it is a member connected to the standing portion of the first member, A simple cylindrical member that does not constitute a gas flow path may also be used. Further, the shape of the cylindrical member is not limited to a linear shape like the gas passage member 27, and may be a curved shape.

In the above embodiment, the glass sealing member 197 made of glass is used as the joining member, but any member having a joining function may be made of a material other than glass (for example, made of metal or resin). Further, in the above embodiment, the glass seal member 197 is formed so as to surround the communication hole 108 formed in the lower end plate 106 when viewed in the vertical direction (see FIG. 11), and is a seal that suppresses gas leakage. Although it functions as a member, the glass seal member 197 is not limited to this.

In the above embodiment, the lower terminal plate 420 vertically adjacent to the lower end plate 106 is illustrated as the second member. Members that are not adjacent to each other may also be used. For example, in the above embodiment, one or more intermediate members may be arranged between the lower end plate 106 and the lower terminal plate 420 . In this configuration, the joining member may be a member that joins the lower end plate 106 and the intermediate member, a member that joins the lower terminal plate 420 and the intermediate member, or a member that joins the intermediate members together. good.

In the above-described embodiment, a configuration in which the lower end plate 106 is provided with the reinforcing portion 523 is employed as means for increasing the rigidity of the overlapping portion 510a of the lower end plate 106 relative to the rigidity of the connecting peripheral portion 520b. As other means, the overlapping portion 510a of the lower end plate 106 is made thicker than the connecting peripheral portion 520b (the overlapping portion 510a and the connecting peripheral portion 520b are made of the same material), A configuration in which ribs or the like are formed in the overlapping portion 510a of the side end plate 106 may be employed.

In the above-described embodiment, the virtual straight lines L1 and L2 extending in mutually opposite directions from the center O of the connecting portion are illustrated as the two virtual straight lines extending in different directions. may be a virtual straight line of For example, in the configuration of FIG. 11, the end through-hole 107 may be positioned at the center of the block communication hole 108B in the longitudinal direction (Y-axis direction) of the block communication hole 108B. In this configuration, the separation distance between the connection portion of the gas passage member 27 and the glass seal member 197 is determined on two imaginary straight lines extending in mutually orthogonal directions (the Y-axis direction and the X-axis direction) from the center O of the connection portion. are different from each other. With such a configuration, it is possible to effectively suppress damage to the joint portion by the glass seal member 197 when the gas passage member 27 is displaced in the Y-axis direction.

Although the holes 32 and 34 are formed in the pair of end plates 104 and 106 in the above embodiment, at least one of the pair of end plates 104 and 106 may not be formed with the holes 32 and 34 . In addition, in the above embodiment, the fuel cell stack 100 includes a pair of terminal plates 410, 420, but other members (for example, a pair of end plates 104, 106) are made to function as terminal plates as dedicated members. terminal plates 410 and 420 may be omitted.

In the above-described embodiment, the single-cell separator 120 has the connecting portion 128 that is curved so as to protrude downward from both the inner portion 126 and the outer portion 127 . The shape may be other shapes. Further, the single cell separator 120 may not have the connecting portion 128 . The same applies to the connecting portion 188 in the IC separator 180 .

In the above embodiment, the glass seal portion 125 is arranged near the hole 121 in the single cell separator 120, but the glass seal portion 125 may be omitted.

Although the interconnector 190 includes the conductive coating layer 194 in the above embodiment, the interconnector 190 may not include the coating layer 194 . Further, although the unit cell 110 has the reaction prevention layer 118 in the above embodiment, the unit cell 110 may not have the reaction prevention layer 118 .

In the above embodiment, the single cell 110 is an anode-supported single cell, but may be an electrolyte-supported, metal-supported, or other type of single cell. Further, in the above embodiment, the fuel cell stack 100 is a counterflow type fuel cell, but the fuel cell stack 100 may be another type of fuel cell such as a coflow type.

In the above embodiment, the number of single cells 110 (the number of power generation units 102) included in the fuel cell stack 100 is merely an example, and the number of single cells 110 depends on the output voltage required for the fuel cell stack 100. can be determined as appropriate. In addition, the materials forming each member in the above-described embodiment are merely examples, and each member may be formed of another material.

In the above embodiments, SOFCs that generate electricity by utilizing the electrochemical reaction between hydrogen contained in the fuel gas and oxygen contained in the oxidant gas are used. The present invention can be similarly applied to an electrolytic cell unit, which is a structural unit of a solid oxide electrolysis cell (SOEC) that generates hydrogen using an electrolytic reaction, and an electrolytic cell stack having a plurality of electrolytic cell units. The configurations of the electrolytic cell unit and the electrolytic cell stack are not described in detail here because they are known, for example, as described in JP-A-2016-81813, but generally the power generation unit 102 in the above-described embodiment and the same configuration as the fuel cell stack 100 . That is, the fuel cell stack 100 in the above-described embodiment can be read as an electrolytic cell stack, the power generation unit 102 can be read as an electrolytic cell unit, and the single cell 110 can be read as an electrolytic single cell. However, during the operation of the electrolytic cell stack, a voltage is applied between both electrodes so that the air electrode 114 is positive (anode) and the fuel electrode 116 is negative (cathode), and the raw material gas is supplied through the manifold. water vapor is supplied as As a result, an electrolysis reaction of water occurs in each electrolysis cell unit, hydrogen gas is generated in the fuel chamber 176, and the hydrogen is taken out of the electrolysis cell stack through the manifold. Even in the electrolytic cell stack having such a configuration, if a configuration similar to that of the above-described embodiment is employed, it is possible to suppress damage to joints by the joint members due to displacement of the gas passage member 27 .

In the above embodiments, a so-called flat-plate type fuel cell stack was used as an example, but the technology disclosed in this specification is not limited to flat-plate type fuel cell stacks. It can also be applied to a flat plate type or cylindrical type fuel cell stack.

In the above embodiments, a solid oxide fuel cell (SOFC) was described as an example, but the technology disclosed in this specification includes a polymer electrolyte fuel cell (PEFC), a phosphoric acid fuel cell (PAFC), Other types of fuel cells (or electrolysis cells) such as molten carbonate fuel cells (MCFC) are also applicable. Furthermore, the technology disclosed in this specification is not limited to an electrochemical reaction cell stack or the like, but includes a first member having a first through hole and a standing portion, and a cylindrical member connected to the standing portion. , a second member, and a joint member that joins the first member and the second member.

22: bolt 24: nut 26: gas through hole 27: gas passage member 28: main body 28a: tip portion 29: flange 100: fuel cell stack 102: power generation unit 103: power generation block 104: upper end plate 106: lower side End plate 107: End through hole 108: Communication hole 108B: Block communication hole 109: Bolt hole 110: Single cell 112: Electrolyte layer 114: Air electrode 116: Fuel electrode 118: Reaction prevention layer 120: Single cell separator 121: Penetration Hole 124: Joint 125: Glass seal portion 130: Air electrode side frame 132: Oxidant gas supply communication hole 133: Oxidant gas discharge communication hole 134: Air electrode side current collector 140: Fuel electrode side frame 142: Fuel gas Supply communication hole 143: Fuel gas discharge communication hole 144: Fuel electrode side current collecting member 145: Electrode facing portion 146: Interconnector facing portion 147: Connection portion 149: Spacer 150: Flat plate portion 161: Oxidant gas supply manifold 162: Oxidation Agent gas discharge manifold 166: Air chamber 171: Fuel gas supply manifold 172: Fuel gas discharge manifold 176: Fuel chamber 180: Separator for IC 189: Bottom plate 190: Interconnector 194: Coating layer 196: Conductive joining material 197: Glass Seal member 197a: Insertion hole 200: Insulating part 210: End separator 220: Upper end plate 310, 510: Flat part 320, 520: Protruding part 322, 522: Outer protruding part 324, 524: Inner protruding part 410, 420: Terminal plate 510a: Overlapping portion 520b: Connection peripheral portion 523: Reinforcement portion 530: Standing portion 600: Reinforcement member 610: Flat plate portion 620: Cylindrical portion FG: Fuel gas FOG: Fuel off-gas OG: Oxidant gas OOG: Oxidant off-gas

Claims (5)

A first through hole penetrating in a first direction is formed, and a cylindrical standing portion is formed that protrudes to one side in the first direction and surrounds the first through hole. a first member;
a cylindrical member connected to the standing portion so as to communicate with the first through hole of the first member;
a second member disposed on the other side in the first direction with respect to the first member;
a joint member disposed between the first member and the second member and disposed around the first through hole when viewed in the first direction; ,
When viewed from the first direction, the joint member is arranged outside a connection peripheral portion of the first member, which is a portion of the cylindrical member surrounding an outline of a connection portion with the standing portion. has been
A complex characterized by: The composite of claim 1, wherein
The second member is arranged adjacent to the first member on the other side in the first direction,
A complex characterized by: In the complex according to claim 1 or claim 2,
Among the first members, the rigidity of the overlapping portion that overlaps with the joint member when viewed in the first direction is higher than the rigidity of the connection peripheral portion.
A complex characterized by: In the composite according to any one of claims 1 to 3,
The joining member is formed with a second through hole surrounding the first through hole when viewed in the first direction,
When viewed from the first direction, at least on two imaginary straight lines extending in different directions from the center of the space surrounded by the outline of the connecting portion of the tubular member, the connecting portion of the tubular member. and the joining member are separated from each other,
A complex characterized by: In the composite according to any one of claims 1 to 4,
The complex is
An electrochemical reaction block composed of a plurality of electrochemical reaction units arranged side by side in the first direction, wherein each of the electrochemical reaction units includes an electrolyte layer and the first electrochemical reaction block with the electrolyte layer interposed therebetween. an electrochemical reaction block having an electrochemical reaction unit cell including an air electrode and an anode that are directionally opposed to each other;
the electrochemical reaction block is arranged on the other side in the first direction with respect to the first member;
the second member is disposed between the electrochemical reaction block and the first member;
A manifold for exchanging gas between a specific electrode, which is at least one of the air electrode and the fuel electrode in each of the electrochemical reaction units, is connected from the inside of the electrochemical reaction block to the first member of the first member. An electrochemical reaction cell stack formed to reach the cylindrical member through one through hole,
A complex characterized by:

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