JP2018181466A - Electrochemical reaction unit and electrochemical reaction cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the worsening of a performance of an electrochemical reaction unit owing to discharge of a gas which has been supplied into a gas chamber and then left unused for a reaction in a single cell while suppressing the increase in the number of parts and the increase in the number of manufacturing steps.SOLUTION: An electrochemical reaction unit comprises: a single cell; a frame member with a gas-chamber hole formed therein for constructing a gas chamber fronting a particular electrode which is at least one of fuel or air electrodes; an interconnector; a current collector for electrically connecting the particular electrode with the interconnector; and a support body for supporting the current collector. In the frame member, a supply-side communication flow path and an exhaust-side communication flow path are formed, opening in an inner circumferential face of the gas-chamber hole. The support body has protrusions located outside a reaction region in the single cell in a particular direction orthogonal to a direction of a line running through a mid point of an opening of the supply-side communication flow path in the inner circumferential face of the gas-chamber hole, and a mid point of an opening of the exhaust-side communication flow path in the inner circumferential face of the gas-chamber hole.SELECTED DRAWING: Figure 8

Description

  The technology disclosed by the present specification relates to an electrochemical reaction unit.

  A solid oxide fuel cell (hereinafter referred to as "SOFC") is known as one of fuel cells that generate electric power using an electrochemical reaction of hydrogen and oxygen. A fuel cell power generation unit (hereinafter, referred to as “power generation unit”), which is a constituent unit of SOFC, includes a single fuel cell (hereinafter, referred to as “single cell”). The unit cell includes an electrolyte layer, and an air electrode and a fuel electrode facing each other in a predetermined direction with the electrolyte layer interposed therebetween.

  In addition, the power generation unit includes a frame member in which a gas chamber hole is formed, which constitutes a fuel chamber facing the fuel electrode of the single cell. In the frame member, in addition to the gas chamber holes, supply side manifold holes constituting a fuel gas supply manifold through which a gas (hereinafter referred to as "fuel gas") supplied to the fuel chamber passes, and are discharged from the fuel chamber An exhaust side manifold hole is formed which constitutes a fuel gas exhaust manifold through which the fuel gas (hereinafter referred to as "fuel off gas") passes. The frame member further communicates with the supply-side manifold hole, and also communicates with the supply-side communication flow passage opened in the inner circumferential surface of the gas chamber hole, and the discharge side manifold hole, and the inner periphery of the gas chamber hole A discharge side communication flow channel opened in the surface is formed. The fuel gas is supplied to the fuel chamber of the power generation unit via the fuel gas supply manifold and the supply side communication flow path. Further, the fuel off gas discharged from the fuel chamber via the discharge side communication flow passage is discharged to the outside via the fuel gas discharge manifold.

  Also, the power generation unit includes a conductive interconnector and a conductive current collector. The current collector is disposed in the fuel chamber, and an electrode facing portion in contact with the surface of the single cell fuel electrode, an interconnector facing portion in contact with the surface of the interconnector, and a connecting portion connecting the electrode facing portion and the interconnector facing portion And. The current collector electrically connects the fuel electrode of the single cell to the interconnector.

  Furthermore, the power generation unit comprises a support arranged in the fuel chamber. The support is a member that contacts the electrode facing portion or the interconnector facing portion of the current collector to support the current collector. By the support, the contact between the electrode facing portion of the current collector and the surface of the fuel electrode, and the contact between the interconnector facing portion of the current collector and the surface of the interconnector are well maintained. Good electrical connection between the fuel electrode of the single cell and the interconnector is maintained.

  Generally, in the power generation unit, the edge of the single cell (more specifically, the reaction area where the power generation reaction actually occurs in the single cell) is extended to a position contacting the inner circumferential surface of the gas chamber hole formed in the frame member. It is difficult, and the edge of the reaction area of the single cell is separated from the inner circumferential surface of the gas chamber hole. If a space through which gas flows (hereinafter referred to as "gas flow passage space") exists between the two, a part of the fuel gas supplied to the fuel chamber is not used for the power generation reaction in a single cell, and the gas Since the fuel is discharged from the fuel chamber via the flow passage space, the power generation efficiency is reduced. Therefore, conventionally, a configuration is known in which a sealing member formed of, for example, felt is installed between the edge of the reaction area of a single cell and the inner peripheral surface of the gas chamber hole (for example, patent document 1). According to such a configuration, the sealing member suppresses the formation of the gas flow passage space between the edge of the reaction area of the single cell and the inner peripheral surface of the gas chamber hole, and thus The amount of fuel gas discharged through the gas flow passage space without being used for the power generation reaction in the cell can be reduced, and the reduction in the power generation efficiency can be suppressed.

JP, 2009-43550, A

  In the above-described conventional configuration, since it is necessary to separately provide a dedicated member such as a felt sealing member, there is a problem that the number of parts increases and the number of manufacturing steps increases.

 Such a problem is not limited to the fuel electrode side, but is common to the air electrode side. Such a problem is also common to the electrolytic cell unit which is a constituent unit of a solid oxide electrolytic cell (hereinafter referred to as "SOEC") which generates hydrogen by utilizing the electrolysis reaction of water. It is. In the present specification, the fuel cell power generation unit and the electrolysis cell unit are collectively referred to as an electrochemical reaction unit. Moreover, such a subject is a subject common to other types of electrochemical reaction units as well as SOFC and SOEC.

  The present specification discloses a technology that can solve the above-described problems.

  The technology disclosed in the present specification can be realized, for example, as the following form.

(1) The electrochemical reaction unit disclosed in the present specification includes: an electrolyte layer; and an air electrode and a fuel electrode facing each other in the first direction across the electrolyte layer; A gas chamber hole provided for a specific electrode which is at least one of the fuel electrode and the air electrode and constituting a gas chamber facing the specific electrode, and a supply side manifold through which a gas supplied to the gas chamber passes A hole for supply side manifold which constitutes, a hole for discharge side manifold which constitutes a discharge side manifold through which a gas discharged from the gas chamber passes, and an inner periphery of the hole for gas chamber while communicating with the hole for supply side manifold At least one supply-side communication flow passage opening in the surface; and at least one discharge-side communication flow passage communicating with the discharge-side manifold hole and opening in the inner circumferential surface of the gas chamber hole; An electrode facing portion provided on the formed frame member, a conductive interconnector, and the specific electrode, disposed in the gas chamber and in contact with the surface of the specific electrode, and an interconnector facing in contact with the surface of the interconnector A conductive current collector having a portion, a connecting portion connecting the electrode facing portion and the interconnector facing portion, and the specific electrode provided, disposed in the gas chamber, the electrode facing portion Support for supporting the current collector in contact with at least one of the surface opposite to the side facing the specific electrode and the surface opposite to the side facing the interconnector of the interconnector facing portion In the electrochemical reaction unit comprising a body, the support is an opening to the inner circumferential surface of the gas chamber hole of the supply side communication flow passage in the first direction view. It is located outside the reaction area in the electrochemical reaction unit cell in a specific direction orthogonal to the direction connecting the middle point and the middle point of the opening to the inner peripheral surface of the gas chamber hole of the discharge side communication flow path. It has a projection. In the electrochemical reaction unit, the support has a protrusion located outside the reaction region in the electrochemical reaction unit cell in the first direction. That is, in the present electrochemical reaction unit, a protrusion of the support exists between the edge of the reaction area of the electrochemical reaction unit cell and the inner peripheral surface of the gas chamber hole. Therefore, in the present electrochemical reaction unit, a gas flow passage space is formed between the edge of the reaction area of the electrochemical reaction unit cell and the inner peripheral surface of the gas chamber hole by the presence of the protrusion of the support. Is suppressed (the cross-sectional area of the gas flow passage space is increased), and the amount of gas discharged through the gas flow passage space is reduced without being used for the reaction in the electrochemical reaction unit cell. be able to. Further, in the present electrochemical reaction unit, the formation suppression of the above-described gas flow path space can be realized using a support for supporting the current collector without separately providing a dedicated member. Therefore, according to the present electrochemical reaction unit, the gas supplied to the gas chamber is discharged without being utilized for the reaction in the electrochemical reaction single cell while suppressing an increase in the number of parts and an increase in the number of manufacturing steps. The performance deterioration of the electrochemical reaction unit can be suppressed.

(2) In the electrochemical reaction unit, a second space continuous to a first space facing the reaction area between the protrusion and the reaction area in the specific direction in the first direction view A space may exist. According to the present electrochemical reaction unit, even if the gas supplied to the gas chamber moves to the outside of the reaction area (that is, between the edge of the reaction area and the inner circumferential surface of the gas chamber hole), the gas Is urged to stay in the second space and return from the second space to the first space facing the reaction region. Therefore, according to the present electrochemical reaction unit, it is possible to effectively reduce the amount of the gas supplied to the gas chamber which is discharged without being used for the reaction in the electrochemical reaction unit cell. The performance deterioration of the chemical reaction unit can be effectively suppressed.

(3) In the electrochemical reaction unit, the second space does not face the reaction region in the first direction view, and the gas chamber hole of the at least one supply communication passage. In the third space facing the opening to the inner peripheral surface of the inner wall, or the opening to the inner peripheral surface of the gas chamber hole of the at least one discharge side communication flow channel not facing the reaction region It may be configured to be continuous to the facing fourth space. According to the electrochemical reaction unit, the second space does not face the reaction area, and the third space faces the opening to the inner peripheral surface of the gas chamber hole of the at least one supply side communication flow path. In the gas chamber, since it is continuous with the space or the fourth space facing the opening to the inner circumferential surface of the gas chamber hole of the at least one discharge side communication channel, not facing the reaction region, and The generation of turbulent flow can be promoted, and as a result, the movement of gas from the second space to the first space facing the reaction region can be promoted. Therefore, according to the present electrochemical reaction unit, it is possible to extremely effectively reduce the amount of the gas supplied to the gas chamber without being utilized for the reaction in the electrochemical reaction unit cell. The performance deterioration of the electrochemical reaction unit can be extremely effectively suppressed.

(4) In the electrochemical reaction unit, the electrochemical reaction unit cell may be a fuel cell unit cell. According to the electrochemical reaction unit, it is possible to reduce the amount of the gas supplied to the gas chamber without being utilized for the power generation reaction in the fuel cell single cell, and the power generation of the electrochemical reaction unit can be reduced. Performance reduction can be suppressed.

(5) The electrochemical reaction cell stack disclosed in the present specification includes an electrochemical reaction cell stack including a plurality of electrochemical reaction units arranged in the first direction, wherein At least one is the above-mentioned electrochemical reaction unit. According to the present electrochemical reaction cell stack, the amount of gas supplied to the gas chamber of at least one electrochemical reaction unit is reduced without being utilized for the reaction in the electrochemical reaction unit cell. It is possible to suppress the performance deterioration of the electrochemical reaction unit.

  The technology disclosed herein can be realized in various forms, for example, an electrochemical reaction unit (a fuel cell power generation unit or an electrolysis cell unit), and an electricity provided with a plurality of electrochemical reaction units. It is possible to realize in the form of a chemical reaction cell stack (fuel cell stack or electrolysis cell stack), a method of manufacturing them, and the like.

It is a perspective view showing the appearance composition of fuel cell stack 100 in this embodiment. It is explanatory drawing which shows the XZ cross-section structure of the fuel cell stack 100 in the position of II-II of FIG. It is explanatory drawing which shows the XZ cross-section structure of the fuel cell stack 100 in the position of III-III of FIG. It is explanatory drawing which shows the XZ cross-section structure of the two adjacent electric power generation units 102 in the same position as the cross section shown in FIG. It is explanatory drawing which shows the XZ cross-section structure of the two adjacent electric power generation units 102 in the same position as the cross section shown in FIG. It is explanatory drawing which shows XY sectional structure of the electric power generation unit 102 in the position of VI-VI of FIG. 4 and FIG. It is explanatory drawing which shows XY sectional structure of the electric power generation unit 102 in the position of VII-VII of FIG. 4 and FIG. It is XY sectional drawing which shows the detailed structure of the surroundings of the support body 149 with which the electric power generation unit 102 is provided. It is YZ sectional drawing which shows the detailed structure of the surroundings of the support body 149 with which the electric power generation unit 102 is provided. It is YZ sectional drawing which shows the detailed structure of the support body 149 periphery with which the electric power generation unit 102X in a comparative example is equipped. It is XY sectional drawing which shows the detailed structure of the surroundings of the support body 149 with which the electric power generation unit 102 in a 1st modification is equipped. It is XY sectional drawing which shows the detailed structure of the surroundings of the support body 149 with which the electric power generation unit 102 in a 2nd modification is equipped.

A. Embodiment:
A-1. Device configuration:
(Configuration of fuel cell stack 100)
FIG. 1 is a perspective view showing an appearance configuration of a fuel cell stack 100 in the present embodiment, and FIG. 2 is an XZ view of the fuel cell stack 100 at a position II-II in FIG. 1 (and FIGS. FIG. 3 is an explanatory view showing a cross-sectional configuration, and FIG. 3 is an explanatory view showing an XZ cross-sectional configuration of the fuel cell stack 100 at a position of III-III in FIG. 1 (and FIGS. In each figure, mutually orthogonal XYZ axes for specifying the direction are shown. In this specification, for convenience, the Z-axis positive direction is referred to as the upward direction, and the Z-axis negative direction is referred to as the downward direction. However, the fuel cell stack 100 actually has an orientation different from such an orientation. It may be installed. The same applies to FIG. Further, in the present specification, a direction orthogonal to the Z-axis direction is referred to as a surface direction.

  The fuel cell stack 100 includes a plurality of (seven in the present embodiment) fuel cell power generation units (hereinafter simply referred to as “power generation units”) 102 and a pair of end plates 104 and 106. The seven power generation units 102 are arranged in a predetermined arrangement direction (vertical direction in the present embodiment). The pair of end plates 104 and 106 are arranged to sandwich an assembly composed of seven power generation units 102 from above and below. The arrangement direction (vertical direction) corresponds to the first direction in the claims.

  As shown in FIG. 1, the layers are vertically penetrated around four corners of the outer periphery around each Z-axis direction of each layer (each power generation unit 102 and end plates 104 and 106) constituting the fuel cell stack 100. Holes are formed, and the holes formed in the respective layers communicate with each other in the vertical direction to form bolt holes 109 extending in the vertical direction from one end plate 104 to the other end plate 106. A bolt 22 is inserted in each bolt hole 109, and the fuel cell stack 100 is fastened by each bolt 22 and a nut not shown.

  Further, as shown in FIGS. 1 to 3, a hole penetrating each power generation unit 102 in the vertical direction is formed in the vicinity of the outer periphery of each power generation unit 102 around the Z-axis direction. The corresponding holes communicate with each other in the vertical direction to form a communication hole 108 extending in the vertical direction across the plurality of power generation units 102. In the following description, a hole formed in each power generation unit 102 to form the communication hole 108 may also be referred to as the communication hole 108.

  As shown in FIGS. 1 and 2, the fuel cell stack 100 is positioned near one side (the side on the X axis positive direction side of the two sides parallel to the Y axis) in the outer periphery around the Z axis direction of the fuel cell stack 100. An oxidant gas supply manifold 161 is a gas flow path through which the oxidant gas OG is introduced from the outside of the fuel cell stack 100 and the oxidant gas OG is supplied to the air chamber 166 of each power generation unit 102 described later. From the air chamber 166 of each of the power generation units 102. The communication hole 108 functions as the second side and is located in the vicinity of the side opposite to the side (the side of the two sides parallel to the Y axis in the negative X axis direction). It functions as an oxidant gas discharge manifold 162 which is a gas flow path for discharging an oxidant off gas OOG which is a discharged gas to the outside of the fuel cell stack 100. In the present embodiment, for example, air is used as the oxidant gas OG.

  Further, as shown in FIGS. 1 and 3, among the sides constituting the outer periphery 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 above-mentioned oxidant gas discharge manifold 162. In the other communication holes 108 located in the fuel cell stack 100, fuel gas FG is introduced from the outside of the fuel cell stack 100, and the fuel gas is supplied to the fuel chamber 176 of each power generation unit 102 described later. The other communication holes 108 located in the vicinity of the side closest to the communication holes 108 which function as the manifold 171 and function as the oxidant gas supply manifold 161 described above are gas discharged from the fuel chamber 176 of each power generation unit 102. As a fuel gas discharge manifold 172 which is a gas flow path for discharging a certain fuel off gas FOG to the outside of the fuel cell stack 100 To function. In the present embodiment, a hydrogen rich gas obtained by reforming city gas, for example, is used as the fuel gas FG. The fuel gas supply manifold 171 corresponds to the supply side manifold in the claims, and the fuel gas discharge manifold 172 corresponds to the discharge side manifold in the claims.

(Configuration of end plates 104 and 106)
The pair of end plates 104 and 106 is a substantially rectangular flat conductive member and is made of, for example, stainless steel. One end plate 104 is disposed on the upper side of the uppermost power generation unit 102, and the other end plate 106 is disposed on the lower side of the lowermost power generation unit 102. The plurality of power generation units 102 are held in a pressed state by the pair of end plates 104 and 106. The upper end plate 104 functions as a positive output terminal of the fuel cell stack 100, and the lower end plate 106 functions as a negative output terminal of the fuel cell stack 100. As shown in FIG. 2 and FIG. 3, four flow path through holes 107 are formed in the lower end plate 106. The four flow path through holes 107 are in communication with the oxidant gas supply manifold 161, the oxidant gas discharge manifold 162, the fuel gas supply manifold 171, and the fuel gas discharge manifold 172, respectively.

(Configuration of gas passage member 27 etc.)
As shown in FIGS. 2 and 3, the fuel cell stack 100 further includes four gas passages disposed on the opposite side (ie, the lower side) of the lower end plates 106 to the plurality of power generation units 102. A member 27 is provided. The four gas passage members 27 are arranged at positions overlapping the oxidant gas supply manifold 161, the oxidant gas discharge manifold 162, the fuel gas supply manifold 171, and the fuel gas discharge manifold 172 in the vertical direction, respectively. Each gas passage member 27 has a main body portion 28 in which a hole communicating with the flow path through hole 107 of the lower end plate 106 is formed, and a cylindrical branch portion 29 branched from the side surface of the main body portion 28 doing. The hole of the branch portion 29 communicates with the hole of the main body portion 28. A gas pipe (not shown) is connected to the branch portion 29 of each gas passage member 27. An insulating sheet 26 is disposed between the main body 28 of each gas passage member 27 and the end plate 106. The insulating sheet 26 is made of, for example, a mica sheet, a ceramic fiber sheet, a ceramic dust sheet, a glass sheet, a glass ceramic composite agent, or the like.

(Configuration of power generation unit 102)
4 is an explanatory view showing the XZ cross-sectional configuration of two adjacent power generation units 102 at the same position as the cross section shown in FIG. 2, and FIG. 5 is adjacent to each other at the same position as the cross section shown in FIG. FIG. 6 is an explanatory view showing an XZ cross-sectional configuration of two power generation units 102. Note that FIG. 5 shows an enlarged view of a part of the fuel electrode side current collector 144 described later. 6 is an explanatory view showing an XY cross-sectional configuration of the power generation unit 102 at the position of VI-VI in FIG. 4 and FIG. 5, and FIG. 7 is a power generation unit at the position of VII-VII in FIG. It is explanatory drawing which shows XY cross-section structure of 102. FIG.

  As shown in FIGS. 4 and 5, the power generation unit 102 includes the unit cell 110, the separator 120, the air electrode side frame 130, the air electrode side current collector 134, the fuel electrode side frame 140, and the fuel electrode side. A current collector 144 and a pair of interconnectors 150 constituting the top layer and the bottom layer of the power generation unit 102 are provided. Holes constituting the communication holes 108 functioning as the above-described manifolds 161, 162, 171, 172 at the peripheral portion around the Z axis direction in the separator 120, the air electrode side frame 130, the fuel electrode side frame 140, and the interconnector 150 Also, holes forming the respective bolt holes 109 are formed.

  The interconnector 150 is a substantially rectangular flat conductive member and is made of, for example, ferritic stainless steel. The interconnector 150 ensures electrical continuity between the power generation units 102 and prevents the mixing of reaction gases between the power generation units 102. In the present embodiment, when two power generation units 102 are arranged adjacent to each other, one interconnector 150 is shared by the two adjacent power generation units 102. That is, the upper interconnector 150 in a certain power generation unit 102 is the same member as the lower interconnector 150 in another power generation unit 102 adjacent to the upper side of the power generation unit 102. Further, since fuel cell stack 100 is provided with a pair of end plates 104 and 106, power generation unit 102 located at the top of fuel cell stack 100 does not have upper interconnector 150 and is located at the bottom. The power generation unit 102 does not have the lower interconnector 150 (see FIGS. 2 and 3).

  The unit cell 110 includes an electrolyte layer 112 and an air electrode (cathode) 114 and a fuel electrode (anode) 116 which face each other in the vertical direction (arrangement direction in which the power generation units 102 are arranged) sandwiching the electrolyte layer 112. The unit cell 110 of this embodiment is a unit cell of the fuel electrode support type in which the electrolyte layer 112 and the air electrode 114 are supported by the fuel electrode 116.

  The electrolyte layer 112 is a flat plate-shaped member that is substantially rectangular in the Z direction, and is a dense layer. The electrolyte layer 112 is formed of, for example, a solid oxide such as YSZ (yttria-stabilized zirconia), ScSZ (scandia-stabilized zirconia), SDC (samarium-doped ceria), GDC (gadolinium-doped ceria), or perovskite-type oxide. There is. Thus, the unit cell 110 (power generation unit 102) of the present embodiment is a solid oxide fuel cell (SOFC) using a solid oxide as an electrolyte. The air electrode 114 is a substantially rectangular flat plate-shaped member smaller than the electrolyte layer 112 in the Z direction, and is a porous layer. The air electrode 114 is made of, for example, a perovskite type oxide (for example, LSCF (lanthanum strontium cobalt iron oxide), LSM (lanthanum strontium manganese oxide), LNF (lanthanum nickel iron)). The fuel electrode 116 is a substantially rectangular flat plate-like member having substantially the same size as the electrolyte layer 112 in the Z direction, and is a porous layer. The fuel electrode 116 is formed of, for example, a cermet composed of Ni and oxide ion conductive ceramic particles (for example, YSZ). The fuel electrode 116 corresponds to the specific electrode in the claims.

  In the unit cell 110, a region in which the power generation reaction substantially occurs is a region in which all of the air electrode 114, the electrolyte layer 112, and the fuel electrode 116 are present as viewed in the Z-axis direction. In this specification, this region in the single cell 110 is referred to as a reaction region RR (see FIGS. 4, 5 and 7).

  The separator 120 is a frame-shaped member in which a substantially rectangular hole 121 penetrating in the vertical direction is formed in the vicinity of the center, and is formed of, for example, metal. The peripheral portion of the hole 121 in the separator 120 faces the peripheral portion of the surface of the electrolyte layer 112 on the air electrode 114 side. The separator 120 is bonded to the electrolyte layer 112 (unit cell 110) by a bonding portion 124 formed of a brazing material (for example, Ag wax) disposed in the facing portion. The air chamber 166 facing the air electrode 114 and the fuel chamber 176 facing the fuel electrode 116 are separated by the separator 120, and the gas leaks from the one electrode side to the other electrode side in the peripheral portion of the unit cell 110. Be suppressed.

 The air electrode side frame 130 is a frame-shaped member in which a substantially rectangular gas chamber hole 131 penetrating in the vertical direction is formed in the vicinity of the center, and is formed of, for example, an insulator such as mica. The air electrode side frame 130 is in contact with the peripheral portion of the surface of the separator 120 opposite to the side facing the electrolyte layer 112 and the peripheral portion of the surface of the interconnector 150 facing the air electrode 114. . Further, the air electrode side frame 130 electrically insulates between the pair of interconnectors 150 included in the power generation unit 102.

  As shown in FIGS. 4 to 6, the gas chamber hole 131 of the air electrode side frame 130 is a hole that constitutes the air chamber 166 facing the air electrode 114. Further, an oxidant gas supply communication channel 132 which communicates with the communication hole 108 constituting the oxidant gas supply manifold 161 and opens in the inner peripheral surface of the gas chamber hole 131 in the air electrode side frame 130, an oxidant An oxidant gas discharge communication channel 133 is formed which is in communication with the communication hole 108 constituting the gas discharge manifold 162 and which is open on the inner peripheral surface of the gas chamber hole 131. In the present embodiment, in the air electrode side frame 130, three oxidant gas supply communication channels 132 and three oxidant gas discharge communication channels 133 are formed.

  The fuel electrode side frame 140 is a frame-shaped member in which a substantially rectangular gas chamber hole 141 penetrating in the vertical direction is formed in the vicinity of the center, and is made of, for example, metal. The fuel electrode side frame 140 is in contact with the peripheral portion of the surface of the separator 120 facing the electrolyte layer 112 and the peripheral portion of the surface of the interconnector 150 facing the fuel electrode 116.

  As shown in FIGS. 4, 5 and 7, the gas chamber hole 141 of the fuel electrode side frame 140 is a hole that constitutes the fuel chamber 176 facing the fuel electrode 116. The gas chamber hole 141 has a first inner circumferential surface IP1 and a second inner circumferential surface IP2 facing each other in the X-axis direction. Further, as shown in FIGS. 5 and 7, the fuel electrode side frame 140 communicates with the communication hole 108 constituting the fuel gas supply manifold 171 and is open at the first inner circumferential surface IP1 of the gas chamber hole 141. And a fuel gas discharge communication channel 143 communicating with the communication hole 108 constituting the fuel gas discharge manifold 172 and opening in the second inner circumferential surface IP2 of the gas chamber hole 141. It is formed. In the present embodiment, one fuel gas supply communication channel 142 and one fuel gas discharge communication channel 143 are formed in the fuel electrode side frame 140.

  The fuel electrode side frame 140 corresponds to the frame member in the claims, and the gas chamber holes 141 correspond to the gas chamber holes in the claims. Further, among the communication holes 108 formed in the fuel electrode side frame 140, the communication holes 108 constituting the fuel gas supply manifold 171 correspond to the supply side manifold holes in the claims, and the fuel gas discharge manifold 172 The communication hole 108 which is configured corresponds to the discharge side manifold hole in the claims. Further, the fuel gas supply communication channel 142 formed in the fuel electrode side frame 140 corresponds to the supply communication channel in the claims, and the fuel gas discharge communication channel 143 has the exhaust side in the claims. It corresponds to the communication channel.

  As shown in FIGS. 4 to 6, the air electrode side current collector 134 is a conductive member disposed in the air chamber 166. The air electrode side current collector 134 is composed of a plurality of substantially square pole shaped current collector elements 135, and is made of, for example, ferritic stainless steel. The air electrode side current collector 134 is in contact with the surface of the air electrode 114 opposite to the side facing the electrolyte layer 112 and the surface of the interconnector 150 opposite to the air electrode 114. However, as described above, since the power generation unit 102 positioned at the top in the fuel cell stack 100 does not have the upper interconnector 150, the air electrode side current collector 134 in the power generation unit 102 is the upper end plate It is in contact with 104. Because of such a configuration, the air electrode side current collector 134 electrically connects the air electrode 114 and the interconnector 150 (or the end plate 104). In the present embodiment, the air electrode side current collector 134 and the interconnector 150 are formed as an integral member. That is, a flat plate-shaped portion of the integral member which is orthogonal to the vertical direction (Z-axis direction) functions as the interconnector 150 and is formed so as to project from the flat-plate portion toward the air electrode 114 The plurality of convex portions, ie, the current collector elements 135 function as the air electrode side current collector 134. In addition, the integral member of the air electrode side current collector 134 and the interconnector 150 may be covered with a conductive coat, and between the air electrode 114 and the air electrode side current collector 134 A conductive bonding layer to be bonded may be interposed.

  As shown in FIGS. 4, 5 and 7, the fuel electrode side current collector 144 is a conductive member disposed in the fuel chamber 176. The fuel electrode side current collector 144 includes an interconnector facing portion 146, an electrode facing portion 145, and a connecting portion 147 connecting the electrode facing portion 145 and the interconnector facing portion 146. In the present embodiment, the fuel electrode side current collector 144 is formed of a nickel foil (for example, a thickness of 10 to 200 μm). As shown in the partial enlarged view in FIG. 5, the fuel electrode side current collector 144 is manufactured by cutting a substantially rectangular nickel foil and processing it so that a plurality of rectangular portions are bent up. Each rectangular portion bent and bent becomes an electrode facing portion 145, and a flat plate portion with holes OP opened other than the bent and bent portion becomes an interconnector facing portion 146, and the electrode facing portion 145 and the interconnector facing portion 146 The connecting portion is the connecting portion 147. Note that, in the partially enlarged view in FIG. 5, in order to show the method of manufacturing the fuel electrode side current collector 144, a state before bending and raising processing is completed is shown for a part of rectangular portions.

  The electrode facing portion 145 of the fuel electrode side current collector 144 is in contact with the surface of the fuel electrode 116 opposite to the side facing the electrolyte layer 112, and the interconnector facing portion 146 is the fuel electrode in the interconnector 150. It is in contact with the surface opposite to 116. However, as described above, since the lowermost power generation unit 102 in the fuel cell stack 100 does not have the lower interconnector 150, the interconnector facing portion 146 in the power generation unit 102 is the lower end plate Contact 106. The fuel electrode side current collector 144 electrically connects the fuel electrode 116 and the interconnector 150 (or the end plate 106) because of such a configuration. The fuel electrode side current collector 144 corresponds to the current collector in the claims.

  In addition, a support 149 formed of, for example, mica is disposed between the electrode facing portion 145 and the interconnector facing portion 146. The support 149 is a surface of the electrode facing portion 145 of the fuel electrode side current collector 144 opposite to the surface facing the fuel electrode 116, and a side opposite to the surface facing the interconnector 150 of the interconnector facing portion 146. The fuel electrode side current collector 144 is supported in contact with the surface of the fuel cell. By the support 149, the contact between the electrode facing portion 145 and the fuel electrode 116 and the contact between the interconnector facing portion 146 and the interconnector 150 are well maintained. As a result, the fuel electrode side current collector 144 is interposed. The electrical connection between the fuel electrode 116 and the interconnector 150 (or the end plate 106) is well maintained.

A-2. Operation of Fuel Cell Stack 100:
As shown in FIGS. 2, 4 and 6, the oxidant gas OG is supplied via a gas pipe (not shown) connected to the branch portion 29 of the gas passage member 27 provided at the position of the oxidant gas supply manifold 161. When supplied, the oxidant gas OG is supplied to the oxidant gas supply manifold 161 via the branch portion 29 of the gas passage member 27, the main body portion 28, and the flow path through hole 107 of the lower end plate 106. The air is supplied from the oxidant gas supply manifold 161 to the air chamber 166 via the oxidant gas supply communication channel 132 of each power generation unit 102. Further, as shown in FIGS. 3, 5 and 7, the fuel gas FG is supplied via a gas pipe (not shown) connected to the branch portion 29 of the gas passage member 27 provided at the position of the fuel gas supply manifold 171. When supplied, the fuel gas FG is supplied to the fuel gas supply manifold 171 through the branch portion 29 of the gas passage member 27, the main body portion 28, and the flow path through hole 107 of the lower end plate 106. The fuel gas is supplied from the fuel gas supply manifold 171 to the fuel chamber 176 via the fuel gas supply communication channel 142 of each power generation unit 102.

  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, oxygen contained in the oxidant gas OG and hydrogen contained in the fuel gas FG in the single cell 110 Power generation is performed by electrochemical reaction with the 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 one of the interconnectors 150 through the air electrode side current collector 134, and the fuel electrode 116 is through the fuel electrode side current collector 144. The other interconnector 150 is electrically connected. Also, the plurality of power generation units 102 included in the fuel cell stack 100 are electrically connected in series. Therefore, the electrical energy generated in each power generation unit 102 is taken out from the end plates 104 and 106 functioning as the output terminals of the fuel cell stack 100. Since the SOFC generates power at a relatively high temperature (eg, 700 ° C. to 1000 ° C.), the fuel cell stack 100 is heated (after start-up, until the heat can be maintained by the heat generated by the power generation). (Not shown).

  The oxidant off gas OOG discharged from the air chamber 166 of each power generation unit 102 is discharged to the oxidant gas discharge manifold 162 through the oxidant gas discharge communication channel 133, as shown in FIGS. Further, it is connected to the branch portion 29 through the flow path through hole 107 of the lower end plate 106, the main body portion 28 and the branch portion 29 of the gas passage member 27 provided at the position of the oxidant gas discharge manifold 162. The fuel is discharged to the outside of the fuel cell stack 100 through gas piping (not shown). In addition, the fuel off gas FOG discharged from the fuel chamber 176 of each power generation unit 102 is discharged to the fuel gas discharge manifold 172 via the fuel gas discharge communication channel 143, as shown in FIGS. A gas pipe connected to the branch portion 29 through the flow path through hole 107 of the lower end plate 106, the main body portion 28 of the gas passage member 27 provided at the position of the fuel gas discharge manifold 172, and the branch portion 29. The fuel is discharged to the outside of the fuel cell stack 100 (not shown).

  As shown in FIG. 6, in each power generation unit 102 constituting the fuel cell stack 100 of the present embodiment, the oxidant gas supply communication channel 132 in the gas chamber hole 131 of the air electrode side frame 130 is opened. The opposing direction of the circumferential surface and the inner circumferential surface where the oxidant gas discharge communication channel 133 opens is the X axis direction. Therefore, the main flow direction of the oxidant gas OG in the air chamber 166 of each power generation unit 102 is a direction generally from the X-axis positive direction side to the X-axis negative direction side. Further, as shown in FIG. 7, the inner peripheral surface (first inner peripheral surface IP1) and the fuel gas discharge communication channel in which the fuel gas supply communication channel 142 opens in the gas chamber hole 141 of the fuel electrode side frame 140 The opposing direction with the inner circumferential surface (second inner circumferential surface IP2) where the opening 143 is the X axis direction. Therefore, the main flow direction of the fuel gas FG in the fuel chamber 176 of each power generation unit 102 is a direction generally from the X-axis negative direction side to the X-axis positive direction side. Thus, in the power generation unit 102 of the present embodiment, the main flow direction of the oxidant gas OG in the air chamber 166 and the main flow direction of the fuel gas FG in the fuel chamber 176 are substantially opposite directions (directions opposite each other) It is a counterflow type SOFC.

A-3. Detailed Configuration of Support 149:
Next, the detailed configuration of the support 149 provided in the power generation unit 102 will be described. FIG. 8 is an XY cross-sectional view showing a detailed configuration around the support 149 provided in the power generation unit 102. As shown in FIG. In FIG. 8, among the XY cross-sectional configurations shown in FIG. 7, a part of the configuration including the support 149 is extracted and illustrated, and the other configurations are appropriately omitted. FIG. 9 is a YZ sectional view showing a detailed configuration around the support 149 provided in the power generation unit 102. As shown in FIG. FIG. 9 shows the YZ cross-sectional configuration of the power generation unit 102 at the position of IX-IX in FIGS. 7 and 8.

  8, the middle point MP1 of the opening to the first inner circumferential surface IP1 of the gas chamber hole 141 in the fuel gas supply communication channel 142 (the two end points EP11 and EP12 of the opening in the Z axis direction) And the middle point MP2 of the opening to the second inner circumferential surface IP2 of the gas chamber hole 141 in the fuel gas discharge communication channel 143 (a line connecting two end points EP21 and EP22 of the opening) An imaginary straight line VL1 connecting the middle point of the minute) is shown. In the present specification, a direction orthogonal to the virtual straight line VL1 is referred to as a specific direction D1. In the present embodiment, since the direction of the virtual straight line VL1 is a direction substantially parallel to the X-axis direction, the specific direction D1 is a direction substantially parallel to the Y-axis direction.

  As shown in FIGS. 8 and 9, the reaction region RR in the single cell 110 (as described above, it is a region where a power generation reaction occurs, and all of the air electrode 114, the electrolyte layer 112 and the fuel electrode 116 in the Z-axis direction) The edge portion of the region where the light source exists and the inner peripheral surface of the gas chamber hole 141 formed in the fuel electrode side frame 140 are separated from each other.

  As shown in FIGS. 8 and 9, the support 149 is a sheet-like member. In the present embodiment, the thickness of the support body 149 is thicker than the thicknesses of the electrode facing portion 145 and the interconnector facing portion 146 which constitute the fuel electrode side current collector 144. For example, the thickness of the support 149 is preferably five or more times the thickness of the electrode facing portion 145 and the interconnector facing portion 146 that constitute the fuel electrode side current collector 144. The thickness of the support body 149 is, for example, 100 to 1000 μm, while the thickness of the electrode facing portion 145 and the interconnector facing portion 146 constituting the fuel electrode side current collector 144 is, for example, 10 to 200 μm.

  The support 149 protrudes in the specific direction D1 outside the reaction area RR (that is, P1 in FIGS. 8 and 9) in addition to the base 201 overlapping the reaction area RR in the single cell 110 in the Z-axis direction. It has a protrusion 202. In the present embodiment, the protrusions 202 are present on both the one side (upper side in FIG. 8) and the other side (lower side in FIG. 8) of the base 201 along the specific direction D1. Further, each projecting portion 202 extends to a position in contact with the third inner circumferential surface IP3 or the fourth inner circumferential surface IP4 of the gas chamber hole 141.

  Further, as shown in FIG. 8, the support body 149 is formed with a plurality of holes 204 extending substantially in parallel to the Y-axis direction. Both ends of each hole 204 extend to the outside of the reaction zone RR (that is, part P1). Therefore, in the Z-axis direction, a space (hereinafter, referred to as “second space SP2”) exists between the protrusion 202 and the reaction region RR in the specific direction D1. The second space SP2 is continuous with a space (hereinafter, referred to as “first space SP1”) opposed to the reaction region RR in the Z-axis direction.

A-4. Effects of the present embodiment:
As described above, the power generation unit 102 of the fuel cell stack 100 according to the present embodiment includes the electrolyte layer 112 and the air electrode 114 and the fuel electrode 116 facing each other in the Z-axis direction with the electrolyte layer 112 interposed therebetween. The fuel cell is disposed in the fuel cell 176, the fuel cell side frame 140 having the unit cell 110 including the gas chamber hole 141 forming the fuel chamber 176 facing the fuel electrode 116, the conductive interconnector 150, A conductive portion having an electrode facing portion 145 in contact with the surface of the fuel electrode 116, an interconnector facing portion 146 in contact with the surface of the interconnector 150, and a connecting portion 147 connecting the electrode facing portion 145 and the interconnector facing portion 146 And a fuel electrode side current collector 144. The fuel electrode side frame 140 is communicated with a communication hole 108 constituting a fuel gas supply manifold 171 through which the gas supplied to the fuel chamber 176 passes, and a fuel gas exhaust manifold 172 through which the gas discharged from the fuel chamber 176 passes. A fuel gas supply communication channel 142 communicating with the hole 108 and the communication hole 108 constituting the fuel gas supply manifold 171 and opening on the first inner circumferential surface IP1 of the gas chamber hole 141, the fuel gas discharge manifold 172 A fuel gas discharge communication channel 143 is formed which communicates with the communication hole 108 and which is open to the second inner circumferential surface IP2 of the gas chamber hole 141. Further, the power generation unit 102 is disposed in the fuel chamber 176, and the surface of the electrode facing portion 145 of the fuel electrode side current collector 144 opposite to the side facing the fuel electrode 116 and the inter face of the interconnector facing portion 146 A support 149 supporting the fuel electrode side current collector 144 is provided in contact with a surface opposite to the side facing the connector 150 to support the fuel electrode side current collector 144. The support 149 is, as viewed in the Z-axis direction, the middle point MP 1 of the opening of the fuel gas supply communication channel 142 to the first inner peripheral surface IP 1 and the second inner peripheral surface IP 2 of the fuel gas discharge communication channel 143. In the specific direction D1 orthogonal to the direction connecting the middle point MP2 of the opening (the direction of the virtual straight line VL1), the protrusion 202 is located outside the reaction area RR in the single cell 110. Therefore, according to the power generation unit 102 of the present embodiment, it is possible to suppress the performance decrease of the power generation unit 102 while suppressing an increase in the number of parts and an increase in the number of manufacturing steps as described below.

  FIG. 10 is a YZ cross-sectional view showing the detailed configuration around the support 149 provided in the power generation unit 102X in the comparative example. In the power generation unit 102X of the comparative example shown in FIG. 10, the support 149 has the projecting portion 202 located outside the reaction area RR in the single cell 110 (that is, P1 part in FIG. 10) in the Z-axis direction. Absent. Therefore, in the power generation unit 102X of the comparative example, between the edge of the reaction area RR of the single cell 110 and the third inner circumferential surface IP3 (or fourth inner circumferential surface IP4) of the gas chamber hole 141 (ie, A large gas flow path space FS is formed in P1 part). Therefore, in the power generation unit 102X of the comparative example, of the fuel gas FG supplied to the fuel chamber 176, the fuel gas FG of a certain amount or more is not utilized for the power generation reaction in the single cell 110, Since the fuel is discharged from the fuel chamber 176 through the FS, the power generation efficiency is reduced.

  On the other hand, in the power generation unit 102 of the present embodiment, the support body 149 has the protruding portion 202 located outside the reaction region RR (that is, the P1 portion) in the single cell 110. That is, in the power generation unit 102 of the present embodiment, between the edge of the reaction area RR of the single cell 110 and the third inner circumferential surface IP3 (or fourth inner circumferential surface IP4) of the gas chamber hole 141 (that is, , P1), the protrusion 202 of the support 149 is present. Therefore, in the power generation unit 102 of the present embodiment, the third inner circumferential surface IP3 of the reaction chamber RR of the unit cell 110 and the third inner circumferential surface IP3 of the gas chamber hole 141 (or the fourth inner circumferential surface IP3) Formation of the gas flow passage space FS between the inner surface IP4 of the fuel cell and the cross section of the gas flow passage space FS is suppressed, and is utilized for the power generation reaction in the single cell 110. It is possible to reduce the amount of fuel gas FG discharged through the gas flow passage space FS. Further, in the power generation unit 102 of the present embodiment, the formation of the gas flow path space FS described above is suppressed using the support 149 that supports the fuel electrode side current collector 144 without separately providing a dedicated member. Cross sectional area increase suppression of the flow path space FS can be realized. Therefore, according to the power generation unit 102 of the present embodiment, the fuel gas FG supplied to the fuel chamber 176 is discharged without being used for the power generation reaction in the single cell 110 while suppressing an increase in the number of parts and an increase in the number of manufacturing steps. It is possible to suppress the performance deterioration of the power generation unit 102 due to the

In order to effectively reduce the amount of fuel gas FG discharged without being used for the power generation reaction in unit cell 110, the fuel chamber in a cross section parallel to the Z-axis direction (for example, the YZ cross section shown in FIG. 9) Between the edge of the reaction area RR of the unit cell 110 in the support 176 and the support 149 and the third inner circumferential surface IP3 (or fourth inner circumferential surface IP4) of the gas chamber hole 141 (that is, P1 part) It is preferable that the ratio of the cross-sectional area of the support body 149 (projection part 202) to the cross-sectional area of the located part (S1 part of FIG. 9) is 30% or more, and it is more preferable that it is 50% or more. Further, in order to effectively reduce the amount of the fuel gas FG discharged without being used for the power generation reaction in the single cell 110, the support 149 is preferably formed of a high density material. For example, mica has a density of about 2 g / cm ³ and a much higher density than felt (density: about 0.15 g / cm ³ ) or the like, so by forming the support 149 with mica, The amount of fuel gas FG discharged without being used for the power generation reaction in the unit cell 110 can be effectively reduced. The density of the support 149 is, for example, preferably 1 g / cm ³ or more, and more preferably 1.5 g / cm ³ or more.

  Further, in the power generation unit 102 of the present embodiment, the protrusion 202 is present on both the one side and the other side along the specific direction D1 with respect to the base 201. Therefore, according to the power generation unit 102 of the present embodiment, of the fuel gas FG supplied to the fuel chamber 176, the amount of the fuel gas FG discharged without being used for the power generation reaction in the single cell 110 is effectively It is possible to reduce the performance deterioration of the power generation unit 102 effectively. Further, in the power generation unit 102 of the present embodiment, each protrusion 202 extends to a position in contact with the inner peripheral surface (the third inner peripheral surface IP3 or the fourth inner peripheral surface IP4) of the gas chamber hole 141 ing. Therefore, according to the power generation unit 102 of the present embodiment, among the fuel gas FG supplied to the fuel chamber 176, the amount of the fuel gas FG discharged without being used for the power generation reaction in the single cell 110 is more effective. It is possible to reduce the performance deterioration of the power generation unit 102 more effectively.

  Further, in the power generation unit 102 of the present embodiment, the first space SP1 facing the reaction region RR is continuous between the protrusion 202 of the support 149 in the specific direction D1 and the reaction region RR in the Z-axis direction. There exists a second space SP2. Therefore, even if the fuel gas FG supplied to the fuel chamber 176 moves to the outside (that is, P1 part) of the reaction region RR, the fuel gas FG enters and remains in the second space SP2, and the second space It is urged from SP2 to return to the first space SP1 opposite to the reaction area RR. Therefore, according to the power generation unit 102 of the present embodiment, of the fuel gas FG supplied to the fuel chamber 176, the amount of the fuel gas FG discharged without being used for the power generation reaction in the single cell 110 is effectively It is possible to reduce the performance deterioration of the power generation unit 102 effectively.

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

  FIG. 11 is an XY cross-sectional view showing a detailed configuration around the support 149 provided in the power generation unit 102 in the first modification. In the power generation unit 102 in the first modification shown in FIG. 11, a part of the plurality of second spaces SP2 existing between the protrusion 202 and the reaction region RR in the specific direction D1 as viewed in the Z-axis direction (The space shown at the leftmost side in FIG. 11) does not face the reaction region RR, and faces the opening to the first inner circumferential surface IP1 of the gas chamber hole 141 of the fuel gas supply communication channel 142 (Hereinafter, referred to as “third space SP3”). Further, in the power generation unit 102 in the first modified example shown in FIG. 11, another part of the plurality of second spaces SP2 (the space shown on the right in FIG. 11) is viewed in the Z-axis direction. A space which does not face the reaction area RR and which faces the opening to the second inner circumferential surface IP2 of the gas chamber hole 141 of the fuel gas discharge communication channel 143 (hereinafter referred to as “fourth space SP4” It is continuous to).

  Thus, in the power generation unit 102 in the first modification shown in FIG. 11, the plurality of second spaces SP2 existing between the protrusion 202 and the reaction region RR in the specific direction D1 as viewed in the Z-axis direction Since a part of the space is continuous with the third space SP3 or the fourth space SP4, generation of turbulent flow can be promoted in the fuel chamber 176, and as a result, the reaction area RR from the second space SP2 It is possible to promote the movement of the fuel gas FG to the first space SP1 opposite to. Therefore, according to the power generation unit 102 in the first modification shown in FIG. 11, of the fuel gas FG supplied to the fuel chamber 176, the fuel gas FG discharged without being used for the power generation reaction in the single cell 110. Of the power generation unit 102 can be extremely effectively reduced, and the performance degradation of the power generation unit 102 can be extremely effectively suppressed.

  FIG. 12 is an XY cross-sectional view showing the detailed configuration around the support 149 provided in the power generation unit 102 in the second modification. In the power generation unit 102 in the first modification shown in FIG. 12, as in the power generation unit 102 in the first modification shown in FIG. 11, a part of the plurality of second spaces SP2 is the third space. It is continuous with SP3 or the fourth space SP4. Therefore, according to the power generation unit 102 in the second modification shown in FIG. 12, the single fuel fuel FG supplied to the fuel chamber 176 is the same as the power generation unit 102 in the first modification shown in FIG. The amount of the fuel gas FG discharged without being utilized for the power generation reaction in the cell 110 can be extremely effectively reduced, and the performance deterioration of the power generation unit 102 can be extremely effectively suppressed. Further, in the power generation unit 102 in the first modification shown in FIG. 12, another portion of the plurality of second spaces SP2 (a space shown near the center in the horizontal direction in FIG. ) Constitute one space continuously with one another. Therefore, generation of turbulence can be more effectively promoted in fuel chamber 176 in power generation unit 102 in the first modification shown in FIG. 12, and as a result, reaction space RR faces reaction region RR. The movement of the fuel gas FG to the first space SP1 can be effectively promoted. Therefore, according to the power generation unit 102 in the first modification shown in FIG. 12, of the fuel gas FG supplied to the fuel chamber 176, the fuel gas FG discharged without being used for the power generation reaction in the single cell 110 Can be more effectively reduced, and the performance degradation of the power generation unit 102 can be more effectively suppressed.

  The configuration of the power generation unit 102 or the fuel cell stack 100 according to the above-described embodiment (and the modifications, the same applies to the following) is merely an example, and various modifications can be made. For example, in the above embodiment, the support 149 has the protrusions 202 on both the one side and the other side along the specific direction D1, but has the protrusions 202 on only one side along the specific direction D1. It may be Further, in the above embodiment, the projecting portion 202 extends to a position in contact with the inner peripheral surface of the gas chamber hole 141, but the projecting portion 202 necessarily extends to the inner peripheral surface of the gas chamber hole 141 There is no need. For example, it is preferable that the projecting portion 202 extend a half or more of the length from the edge of the reaction area RR to the inner circumferential surface of the gas chamber hole 141, and the gas chamber hole from the edge of the reaction area RR. More preferably, it is stretched by two thirds or more of the length to the inner circumferential surface of 141.

  Further, in the above embodiment, the support 149 abuts on both the surface of the electrode facing portion 145 of the fuel electrode side current collector 144 and the surface of the interconnector facing portion 146 to support the fuel electrode side current collector 144 However, the support 149 may be in contact with any one of the surface of the electrode facing portion 145 and the surface of the interconnector facing portion 146 to support the fuel electrode side current collector 144.

  Further, in the above embodiment, the second space SP2 continuous to the first space SP1 facing the reaction area RR is present between the protrusion 202 and the reaction area RR in the specific direction D1 in the Z-axis direction. However, such a second space SP2 does not necessarily have to exist.

  Further, in the above embodiment, one fuel gas supply communication channel 142 and one fuel gas discharge communication channel 143 are formed in the fuel electrode side frame 140, but the fuel gas supply communication channel 142 is A plurality of fuel gas discharge communication channels 143 may be formed. When a plurality of fuel gas supply communication channels 142 (or fuel gas discharge communication channels 143, the same applies hereinafter) is formed, “the inner peripheral surface of the gas chamber hole 141 of the fuel gas supply communication channel 142 is used. The middle point of the opening of the opening is a center of a figure formed by connecting the middle points of the openings to the inner peripheral surface of the gas chamber holes 141 of the plurality of fuel gas supply communication channels 142 by a line segment means. For example, in the case where two fuel gas supply communication flow channels 142 are formed, “the middle point of the opening of the fuel gas supply communication flow channel 142 to the inner peripheral surface of the gas chamber hole 141” The middle point of the opening of the fuel gas supply communication channel 142 to the inner circumferential surface of the gas chamber hole 141 and the middle point of the opening of the other fuel gas supply communication channel 142 to the inner circumferential surface of the gas chamber hole 141 And the midpoint of the line connecting

  Further, in the above embodiment, although the bolt holes 109 are provided independently of the communication holes 108 for each manifold, the independent bolt holes 109 are not provided, and the communication holes 108 for each manifold are bolt holes. May also be used. In the above embodiment, an intermediate layer may be disposed between the air electrode 114 and the electrolyte layer 112. Further, in the above embodiment, the number of the power generation units 102 included in the fuel cell stack 100 is merely an example, and the number of the power generation units 102 is appropriately determined according to the output voltage and the like required for the fuel cell stack 100. Moreover, the material which comprises each member in the said embodiment is an illustration to the last, and each member may be comprised with another material.

  Further, in the above embodiment, it is not necessary to adopt the configuration in which the support body 149 has the projecting portion 202 for all the power generation units 102 included in the fuel cell stack 100, and at least one of the fuel cell stack 100 If the above configuration is adopted for two power generation units 102, among the fuel gas FG supplied to the fuel chamber 176 for the power generation unit 102, the fuel discharged without being used for the power generation reaction in the single cell 110. The amount of gas FG can be reduced, and the performance deterioration of the power generation unit 102 can be suppressed.

  In the above embodiment, the power generation unit 102 is a counterflow type power generation unit 102 in which the main flow direction of the oxidant gas OG in the air chamber 166 and the main flow direction of the fuel gas FG in the fuel chamber 176 are substantially opposite to each other. However, in the present invention, the coflow type power generation unit 102 in which the main flow direction of the oxidant gas OG in the air chamber 166 and the main flow direction of the fuel gas FG in the fuel chamber 176 are substantially the same, The present invention is also applicable to the cross flow type power generation unit 102 in which the angle between the main flow direction of the oxidant gas OG at 166 and the main flow direction of the fuel gas FG in the fuel chamber 176 is 45 degrees or more.

  In the above embodiment, the feature of the support 149 supporting the fuel electrode side current collector 144 disposed in the fuel chamber 176 facing the fuel electrode 116 has been described, but the present invention faces the air electrode 114. The present invention can also be applied to a support that supports the air electrode side current collector disposed in the air chamber 166. When the present invention is applied to the air electrode 114 side, the air electrode 114 corresponds to the specific electrode in the claims.

  Further, in the above embodiment, SOFCs that generate electric power using electrochemical reaction between hydrogen contained in fuel gas and oxygen contained in oxidant gas are targeted, but the present invention relates to the electrolysis reaction of water The present invention is similarly applicable to an electrolysis cell unit that is a constituent unit of a solid oxide electrolytic cell (SOEC) that uses hydrogen to generate hydrogen, and an electrolysis cell stack provided with a plurality of electrolysis cell units. The configuration of the electrolytic cell stack is not described in detail here because it is known as described in, for example, JP-A-2016-81813, but it is roughly similar to the fuel cell stack 100 in the embodiment described above. It is a structure. That is, the fuel cell stack 100 in the embodiment described above may be read as an electrolysis cell stack, the power generation unit 102 may be read as an electrolysis cell unit, and the single cell 110 may be read as an electrolysis single cell. However, during operation of the electrolytic cell stack, a voltage is applied between the two electrodes so that the air electrode 114 is positive (anode) and the fuel electrode 116 is negative (cathode), and through the communication hole 108 Water vapor as a source gas is supplied. As a result, an electrolysis reaction of water occurs in each electrolysis cell unit, hydrogen gas is generated in the fuel chamber 176, and hydrogen is taken out to the outside of the electrolysis cell stack through the communication hole 108. Also in the electrolytic cell unit and the electrolytic cell stack of such a configuration, by adopting the support 149 having the same configuration as that of the above embodiment, it is possible to use only one of the gases supplied to the fuel chamber 176 (or the air chamber 166). The amount of gas exhausted without being used for the reaction in the cell 110 can be reduced, and the performance deterioration of the power generation unit 102 can be suppressed.

 In the above embodiment, the solid oxide fuel cell (SOFC) has been described as an example, but the present invention is also applicable to other types of fuel cells (or electrolytic cells) such as a molten carbonate fuel cell (MCFC). It is applicable.

22: Bolt 26: Insulating sheet 27: Gas passage member 28: Body portion 29: Branching portion 100: Fuel cell stack 102: Fuel cell power generation unit 104: End plate 106: End plate 107: Channel through hole 108: Communication hole 109: bolt hole 110: single cell 112: electrolyte layer 114: air electrode 116: fuel electrode 120: separator 121: hole 124: junction 130: air electrode side frame 131: gas chamber hole 132: oxidant gas supply communication flow Path 133: Oxidizer gas discharge communication flow channel 134: Air electrode side current collector 135: Current collector element 140: Fuel electrode side frame 141: Gas chamber hole 142: Fuel gas supply communication flow channel 143: Fuel gas discharge communication Flow path 144: Fuel electrode side current collector 145: Electrode facing portion 146: Interconnector facing portion 1 47: Connection part 149: Support body 150: Interconnector 161: Oxidizer gas supply manifold 162: Oxidizer gas discharge manifold 166: Air chamber 171: Fuel gas supply manifold 172: Fuel gas discharge manifold 176: Fuel chamber 201: Base 202 : Protrusion 204: Hole

Claims (5)

An electrochemical reaction unit cell including an electrolyte layer, and an air electrode and a fuel electrode facing each other in the first direction across the electrolyte layer;
A gas chamber hole provided for a specific electrode which is at least one of the fuel electrode and the air electrode and constituting a gas chamber facing the specific electrode, and a supply side manifold through which a gas supplied to the gas chamber passes A hole for supply side manifold which constitutes, a hole for discharge side manifold which constitutes a discharge side manifold through which a gas discharged from the gas chamber passes, and an inner periphery of the hole for gas chamber while communicating with the hole for supply side manifold At least one supply-side communication channel opened in the surface, and at least one discharge-side communication channel communicating with the discharge-side manifold hole and opening in the inner circumferential surface of the gas chamber hole are formed A frame member,
Conductive interconnectors,
An electrode facing portion provided for the specific electrode, disposed in the gas chamber, in contact with the surface of the specific electrode, an interconnector facing portion in contact with the surface of the interconnector, the electrode facing portion, and the interconnector facing portion A conductive part connecting the
It is provided about the specific electrode, is arranged in the gas chamber, and the surface of the electrode facing portion opposite to the side facing the specific electrode is opposite to the surface facing the interconnector of the interconnect facing portion. A support that bears against at least one of the side surfaces and supports the current collector;
In the electrochemical reaction unit comprising
The support is a middle point of an opening of the supply-side communication passage to the inner circumferential surface of the gas-chamber hole in the first direction view, and the inside of the gas-chamber hole of the discharge-side communication passage. An electrochemical reaction unit characterized by having a protrusion located outside the reaction area in the electrochemical reaction unit cell in a specific direction orthogonal to the direction connecting the middle point of the opening to the circumferential surface. In the electrochemical reaction unit according to claim 1,
Between the protrusion in the specific direction and the reaction area in the first direction view, there is a second space continuous to the first space facing the reaction area, Electrochemical reaction unit. In the electrochemical reaction unit according to claim 2,
In the first direction, the second space does not face the reaction area, and faces the opening to the inner circumferential surface of the gas chamber hole of the at least one supply-side communication flow path. A third space or a fourth space not facing the reaction area and facing an opening to the inner circumferential surface of the gas chamber hole of the at least one discharge side communication flow path continuously An electrochemical reaction unit characterized in that The electrochemical reaction unit according to any one of claims 1 to 3
The electrochemical reaction unit, wherein the electrochemical reaction unit cell is a fuel cell unit cell. In an electrochemical reaction cell stack comprising a plurality of electrochemical reaction units arranged in the first direction,
An electrochemical reaction cell stack, wherein at least one of the plurality of electrochemical reaction units is the electrochemical reaction unit according to any one of claims 1 to 4.

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