JP2018181405A - Fuel cell power generation module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent degradation in power generation performance of a fuel cell stack.SOLUTION: A fuel cell power generation module comprises: a fuel cell stack having a plurality of unit cells aligned in a first direction; and a heat source. The fuel cell stack is provided with an oxidant gas supply manifold for supplying oxidant gas to an air chamber facing an air electrode of each of the unit cells. In a view perpendicular to the first direction, at least part of the heat source overlaps at least one of the unit cells. In the first direction view, at least part of the heat source faces at least part of a specific virtual side, in a direction perpendicular to the specific virtual side. Here, the specific virtual side is the virtual side closest to the centroid of the oxidant gas supply manifold, among four virtual sides constituting a smallest virtual rectangle that is circumscribed on the contour of the fuel cell stack.SELECTED DRAWING: Figure 6

Description

  The technology disclosed by the present specification relates to a fuel cell power generation module.

  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 unit cell, which is a constituent unit of SOFC, includes an electrolyte layer, and an air electrode and a fuel electrode which face each other in a predetermined direction (hereinafter, referred to as "first direction") with the electrolyte layer interposed therebetween. In general, the SOFC is utilized in the form of a fuel cell stack including a plurality of single cells arranged in the first direction.

  Various manifolds (gas flow paths) are formed in the fuel cell stack. Specifically, in the fuel cell stack, an oxidant gas supply manifold for supplying oxidant gas to the air chamber facing the air electrode of each unit cell, the oxidant off gas discharged from each air chamber to the outside An oxidant gas discharge manifold for discharging, a fuel gas supply manifold for supplying fuel gas to the fuel chamber facing the fuel electrode of each single cell, and a fuel off gas discharged from each fuel chamber are discharged to the outside A fuel gas discharge manifold is formed.

  In addition, an auxiliary may be installed near the fuel cell stack. For example, a combustion chamber for burning the exhaust gas discharged from the fuel cell stack and a reforming chamber for reforming the raw fuel gas to generate the fuel gas to be supplied to the fuel cell stack are formed inside the auxiliary unit. There is. The auxiliaries generate heat as the exhaust gas burns. In the present specification, a configuration including a fuel cell stack and an auxiliary device is referred to as a fuel cell power generation module.

  Generally, the auxiliary unit is disposed at a position facing the fuel cell stack in a first direction (arrangement direction of a plurality of single cells) (see, for example, Patent Document 1).

JP, 2016-18751, A

  Since the oxidant gas and the fuel gas supplied to the fuel cell stack are introduced from the outside of the fuel cell stack, the temperature is relatively low. Further, at the time of operation of the fuel cell stack, in order to increase the utilization rate of hydrogen in the fuel gas, the amount of supply of the oxidant gas is set to a large value as compared with the amount of supply of the fuel gas. Therefore, the area near the oxidant gas supply manifold in each unit cell included in the fuel cell stack is easily deprived of heat by a large amount of oxidant gas, and the temperature is likely to be lowered. When the temperature of a specific area in a single cell decreases, the uniformity of the temperature distribution in the plane of the single cell decreases (that is, the temperature difference between each area of the single cell increases) and the power generation efficiency decreases. As a result, the power generation performance of the fuel cell stack is degraded.

  In the fuel cell power generation module of the conventional configuration described above, since the auxiliary is disposed at a position facing the fuel cell stack in the first direction (arrangement direction of a plurality of single cells), the heat generated by the auxiliary is It hardly contributes to the improvement of the uniformity of the temperature distribution in the plane of a single cell. Therefore, in the fuel cell power generation module of the conventional configuration, there is a problem that the power generation performance of the fuel cell stack is lowered due to the decrease in the uniformity of the temperature distribution in the plane of the single cell. In addition, such a subject is a subject common to not only SOFC but other types of fuel cells.

  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 fuel cell power generation module disclosed in the present specification includes an electrolyte layer and an air electrode and a fuel electrode facing each other with the electrolyte layer interposed therebetween, and a plurality of single fuel cells arranged in the first direction. In a fuel cell power generation module including a fuel cell stack having cells and a heat source, a gas flow for supplying an oxidant gas to an air chamber facing the air electrode of each unit cell in the fuel cell stack. An oxidant gas supply manifold, which is a channel, is formed, and at least a portion of the heat source overlaps with at least one of the unit cells in a direction orthogonal to the first direction, and the first Among the four virtual sides forming the smallest virtual rectangle circumscribing the outer shape of the fuel cell stack in the direction view, the virtual side closest to the centroid of the oxidant gas supply manifold At least a portion of a specific virtual edges that are opposed in a direction perpendicular to the specific virtual edge. In the fuel cell power generation module, at least a portion of the heat source overlaps the at least one unit cell in a direction orthogonal to the first direction, and a diagram of the oxidant gas supply manifold in the first direction. The oxidizing agent in a single cell overlapping with the heat source in a direction perpendicular to the first direction by heat emitted from the heat source because it faces at least a part of the specific imaginary side close to the heart in the direction orthogonal to the specific imaginary side The temperature drop in the area near the gas supply manifold can be suppressed. Therefore, according to the present fuel cell power generation module, it is possible to suppress the decrease in the uniformity of the temperature distribution in the surface of the single cell, and as a result, it is possible to suppress the decrease in the power generation performance of the fuel cell stack.

(2) In the fuel cell power generation module, in the first direction, the outer shape of the fuel cell stack has a linear shape in which at least a part thereof opposes the single cell across the center of the oxidant gas supply manifold. It may be configured to have at least one side. According to the fuel cell power generation module, the heat generated from the heat source effectively suppresses the temperature drop in the region near the oxidant gas supply manifold in the unit cell overlapping the heat source in the direction perpendicular to the first direction. be able to. Therefore, according to the present fuel cell power generation module, it is possible to effectively suppress the decrease in the uniformity of the in-plane temperature distribution in the unit cell, and as a result, the decrease in the power generation performance of the fuel cell stack is effectively suppressed. can do.

(3) In the fuel cell power generation module, the virtual rectangle may be a rectangle, and the specific virtual side may be a short side of the rectangle. In this fuel cell power generation module, since the specific imaginary side close to the centroid of the oxidant gas supply manifold is the short side of the rectangle as an imaginary rectangle, the uniformity of the temperature distribution in the plane of the single cell is likely to deteriorate. As a result, the power generation performance of the fuel cell stack is easily reduced. According to the fuel cell power generation module, even in a configuration in which the power generation performance of the fuel cell stack tends to deteriorate, the heat generated from the heat source causes oxidation in a single cell overlapping the heat source in a direction perpendicular to the first direction. By suppressing the temperature decrease in the region near the agent gas supply manifold, it is possible to suppress the decrease in the uniformity of the temperature distribution in the surface of the single cell, and as a result, the decrease in the power generation performance of the fuel cell stack be able to.

(4) In the fuel cell power generation module, the long side of the rectangle may have a length of 150 mm or more. In this fuel cell power generation module, since the long side of the rectangle as a virtual rectangle is long to some extent, the uniformity of the temperature distribution in the plane of the single cell tends to further deteriorate, and as a result, the performance of the fuel cell stack tends to further deteriorate. It is a structure. According to the present fuel cell power generation module, even in a configuration in which the power generation performance of such a fuel cell stack is further likely to be reduced, heat generated from the heat source causes the unit cell to overlap the heat source in a direction orthogonal to the first direction. By suppressing the temperature decrease in the region near the oxidant gas supply manifold, it is possible to suppress the decrease in the uniformity of the temperature distribution in the surface of the single cell, and as a result, suppress the decrease in the power generation performance of the fuel cell stack. can do.

(5) In the fuel cell power generation module, the fuel cell stack further includes a gas flow path for supplying a fuel gas to a fuel chamber facing the fuel electrode of each of the unit cells, A fuel gas supply manifold may be formed at a position facing the oxidant gas supply manifold across the unit cell in a direction view. In this fuel cell power generation module, the main flow direction of the gas in the air chamber and the main flow direction of the gas in the fuel chamber adopt a configuration of a counter flow type, so that the temperature distribution in the plane of the single cell is The uniformity is further likely to be reduced, and as a result, the power generation performance of the fuel cell stack is further likely to be reduced. According to the present fuel cell power generation module, even in a configuration in which the power generation performance of such a fuel cell stack is further likely to be reduced, heat generated from the heat source causes the unit cell to overlap the heat source in a direction orthogonal to the first direction. By suppressing the temperature decrease in the region near the oxidant gas supply manifold, it is possible to suppress the decrease in the uniformity of the temperature distribution in the surface of the single cell, and as a result, suppress the decrease in the power generation performance of the fuel cell stack. can do.

(6) In the fuel cell power generation module, at least a portion of the heat source is opposed to at least a portion of the oxidant gas supply manifold in a direction orthogonal to the specific imaginary side in the first direction view. It may be According to the fuel cell power generation module, the heat generated from the heat source effectively suppresses the temperature drop in the region near the oxidant gas supply manifold in the unit cell overlapping the heat source in the direction perpendicular to the first direction. Thus, it is possible to effectively suppress the decrease in the uniformity of the in-plane temperature distribution in the unit cell, and as a result, it is possible to effectively suppress the decrease in the power generation performance of the fuel cell stack.

(7) In the fuel cell power generation module, at least a portion of the heat source is opposed to the entire oxidant gas supply manifold in the direction orthogonal to the specific imaginary side in the first direction view. It is also good. According to the fuel cell power generation module, the heat generated from the heat source extremely effectively suppresses the temperature drop of the region near the oxidant gas supply manifold in the unit cell overlapping the heat source in the direction perpendicular to the first direction. By doing this, it is possible to extremely effectively suppress the decrease in the uniformity of the in-plane temperature distribution in the unit cell, and as a result, it is possible to extremely effectively suppress the decrease in the power generation performance of the fuel cell stack.

(8) In the fuel cell power generation module, at least a part of the heat source may overlap all the single cells included in the fuel cell stack in a direction perpendicular to the first direction. According to the fuel cell power generation module, the heat generated from the heat source effectively suppresses the temperature decrease in the region near the oxidant gas supply manifold in all the single cells included in the fuel cell stack. It is possible to suppress the decrease in the uniformity of the in-plane temperature distribution, and as a result, the decrease in the power generation performance of the fuel cell stack can be suppressed more effectively.

(9) In the fuel cell power generation module, the heat source may include an auxiliary device in which a combustion chamber for burning the gas discharged from the fuel cell stack is formed. According to the fuel cell power generation module, the heat of combustion in the combustion chamber of the auxiliary suppresses the temperature drop of the region near the oxidant gas supply manifold in the unit cell overlapping the heat source in the direction perpendicular to the first direction. As a result, it is possible to suppress the decrease in the uniformity of the temperature distribution in the surface of the single cell, and as a result, the decrease in the power generation performance of the fuel cell stack can be suppressed.

  The technology disclosed in this specification can be realized in various forms, for example, a fuel cell power generation module including a fuel cell stack and a heat source, and a method of manufacturing the same. It is possible.

It is a perspective view which shows the external appearance structure of the fuel cell power generation module 20 in this embodiment. It is explanatory drawing which shows the XZ cross-sectional structure of the fuel cell power generation module 20 in the position of II-II of FIG. It is explanatory drawing which shows the XZ cross-sectional structure of the fuel cell power generation module 20 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 explanatory drawing which shows typically the XZ cross-section structure of the electric power generation module 20 of a modification. It is explanatory drawing which shows typically the XY cross-section structure of the electric power generation module 20 of another modification. It is explanatory drawing which shows typically the XY cross-section structure of the electric power generation module 20 of another modification. It is explanatory drawing which shows typically the XY cross-section structure of the electric power generation module 20 of another modification. It is explanatory drawing which shows typically the XY cross-section structure of the electric power generation module 20 of another modification.

A. Embodiment:
A-1. Device configuration:
(Configuration of fuel cell power generation module 20)
FIG. 1 is a perspective view showing an appearance configuration of a fuel cell power generation module (hereinafter simply referred to as “power generation module”) 20 in the present embodiment, and FIG. 2 is a view II of FIG. FIG. 3 is an explanatory view showing the XZ cross-sectional configuration of the power generation module 20 at the position −II, and FIG. 3 shows the XZ cross-sectional configuration of the power generation module 20 at the position III-III in FIG. 1 (and FIGS. FIG. In each figure, mutually orthogonal XYZ axes for specifying the direction are shown. In this specification, for convenience, the positive direction of the Z-axis is referred to as the upper direction, and the negative direction of the Z-axis is referred to as the downward direction. However, the power generation module 20 is actually installed in an orientation different from such an orientation. It may be done. 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 power generation module 20 includes a fuel cell stack 100 and an auxiliary device 200.

(Configuration of fuel cell stack 100)
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. In the present embodiment, the shape of the fuel cell stack 100 as viewed in the Z-axis direction is a rectangle having a side parallel to the X-axis direction as a long side and a side parallel to the Y-axis direction as a short side. The length of the side is 150 mm or more. 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. Further, 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. Further, in the present embodiment, a hydrogen rich gas obtained by reforming city gas, for example, is used as the fuel gas FG.

(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. Each gas passage member 27 is a cylindrical member in which a gas flow passage is formed. 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. As shown in FIG. 2, the first pipe 231 is connected to the gas passage member 27 disposed at a position overlapping the oxidant gas supply manifold 161, and disposed at a position overlapping the oxidant gas discharge manifold 162. The second pipe 232 is connected to the gas passage member 27. Further, as shown in FIG. 3, the third pipe 233 is connected to the gas passage member 27 disposed at a position overlapping the fuel gas supply manifold 171, and disposed at a position overlapping the fuel gas discharge manifold 172. The fourth pipe 234 is connected to the gas passage member 27. An insulating sheet 26 is disposed between 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. 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. 6 and 7 also show the XY cross-sectional configuration of the auxiliary device 200. 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. As described above, since the fuel cell stack 100 includes the plurality of power generation units 102 arranged in the Z-axis direction, the fuel cell stack 100 includes the plurality of single cells 110 arranged in the Z-axis direction. I can say that.

  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. 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). 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.

  6 and 7, in the present embodiment, the shape of the unit cell 110 (more specifically, the shape of the fuel electrode 116) in the Z-axis direction is parallel to the X-axis direction in the present embodiment. The side is a long side, and the side parallel to the Y-axis direction is a short side.

  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 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 hole 131 of the air electrode side frame 130 is a hole forming an air chamber 166 facing the air electrode 114. As shown in FIG. 6, the outline of the hole 131 is substantially rectangular when viewed in the Z-axis direction. Further, as shown in FIG. 4 and FIG. 6, in the air electrode side frame 130, an oxidant gas supply communication channel 132 for connecting the oxidant gas supply manifold 161 and the air chamber 166, an air chamber 166 and an oxidant An oxidant gas discharge communication channel 133 communicating with the gas discharge manifold 162 is formed.

  The fuel electrode side frame 140 is a frame-like member in which a substantially rectangular 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 hole 141 of the fuel electrode side frame 140 is a hole that constitutes the fuel chamber 176 facing the fuel electrode 116. As shown in FIG. 7, the outline of the hole 141 is substantially rectangular when viewed in the Z-axis direction. Further, as shown in FIGS. 5 and 7, the fuel electrode side frame 140 includes a fuel gas supply communication channel 142 for communicating the fuel gas supply manifold 171 with the fuel chamber 176, a fuel chamber 176 and a fuel gas discharge manifold. A fuel gas discharge communication channel 143 communicating with the fuel cell 172 is formed.

  As shown in FIGS. 4 to 6, the air electrode side current collector 134 is 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 disposed in the fuel chamber 176. The fuel electrode side current collector 144 is provided with 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, for example, nickel or nickel alloy , Stainless steel or the like. The electrode facing portion 145 is in contact with the surface of the fuel electrode 116 opposite to the surface facing the electrolyte layer 112, and the interconnector facing portion 146 is on the surface of the interconnector 150 facing the fuel electrode 116. It is in contact. 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. A spacer 149 made of mica, for example, is disposed between the electrode facing portion 145 and the interconnector facing portion 146. Therefore, the fuel electrode side current collector 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 150 (or end plate 106) via the fuel electrode side current collector 144 The electrical connection with is well maintained.

(Configuration of auxiliary device 200)
As shown in FIGS. 1 to 3 and FIGS. 6 and 7, the auxiliary device 200 is a substantially rectangular box-shaped member having a space formed therein, and is formed of, for example, stainless steel or aluminum-added stainless steel. There is. The auxiliary device 200 is fixed to the fuel cell stack 100 by, for example, a fixing member (for example, a bolt) not shown.

  The internal space of the auxiliary device 200 is divided into a primary combustion chamber 212, a reforming chamber 214, and a secondary combustion chamber 216 by two partition walls 222. In the present embodiment, among these three chambers, the primary combustion chamber 212 is disposed closest to the fuel cell stack 100, and the secondary combustion chamber 216 is disposed farthest from the fuel cell stack 100. A chamber 214 is disposed between the primary combustion chamber 212 and the secondary combustion chamber 216.

  The primary combustion chamber 212 is a chamber for mixing and burning the oxidant off gas OOG discharged from the fuel cell stack 100 and the fuel off gas FOG. As shown in FIGS. 2 and 3, the primary combustion chamber 212 is in communication with the gas passage member 27 disposed at a position overlapping the oxidant gas discharge manifold 162 via the second pipe 232, and The fourth pipe 234 is in communication with the gas passage member 27 disposed at a position overlapping the fuel gas discharge manifold 172. Further, the secondary combustion chamber 216 is a chamber for further burning the oxidant off gas OOG and the fuel off gas FOG mixed and burned in the primary combustion chamber 212. The secondary combustion chamber 216 is in communication with the primary combustion chamber 212 via a gas flow passage 218 penetrating the reforming chamber 214. Further, a fifth pipe 235 for discharging the exhaust gas EG to the outside is connected to the secondary combustion chamber 216. In the present embodiment, a catalyst that promotes the combustion of the oxidant off gas OOG and the fuel off gas FOG is disposed in one or both of the primary combustion chamber 212 and the secondary combustion chamber 216.

  The reforming chamber 214 is a chamber for reforming the raw fuel gas RFG to generate a hydrogen-rich fuel gas FG. As shown in FIGS. 2 and 3, the sixth pipe 236 for introducing the raw fuel gas RFG from the outside into the reforming chamber 214 and the seventh pipe for introducing the reforming water RW from the outside 237 are connected. Further, the reforming chamber 214 is in communication with the gas passage member 27 disposed at a position overlapping the fuel gas supply manifold 171 via the third pipe 233. In the present embodiment, the reforming chamber 214 is provided with a catalyst for promoting the reforming reaction.

A-2. Operation of Fuel Cell Stack 100:
As shown in FIG. 2, the oxidant gas OG is introduced into the oxidant gas supply manifold 161 from the first pipe 231 via the gas passage member 27, and the air chamber of each power generation unit 102 from the oxidant gas supply manifold 161. It is supplied to 166. In addition, as shown in FIG. 3, the raw fuel gas RFG (for example, city gas) and the reforming water RW are introduced into the reforming chamber 214 of the auxiliary device 200 from the sixth pipe 236 and the seventh pipe 237, respectively. , Subjected to the reforming reaction. The fuel gas FG generated along with the reforming reaction in the reforming chamber 214 is introduced into the fuel gas supply manifold 171 through the third pipe 233 and the gas passage member 27, and each power generation unit 102 is supplied from the fuel gas supply manifold 171. Is supplied to the fuel chamber 176 of FIG.

  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, which is a gas exhausted from the air chamber 166 of each power generation unit 102, is assisted via the oxidant gas exhaust manifold 162, the gas passage member 27 and the second pipe 232 as shown in FIG. Is introduced into the primary combustion chamber 212 of the vessel 200. Further, as shown in FIG. 3, the fuel off gas FOG which is the gas discharged from the fuel chamber 176 of each power generation unit 102 is assisted via the fuel gas discharge manifold 172, the gas passage member 27 and the fourth pipe 234. Is introduced into the primary combustion chamber 212 of the vessel 200. The oxidant offgas OOG and the fuel offgas FOG introduced into the primary combustion chamber 212 are mixed and burned in the primary combustion chamber 212, are led to the secondary combustion chamber 216 via the gas flow path 218, and are further combusted, and then The exhaust gas is discharged to the outside of the power generation module 20 as an exhaust gas EG through the fifth pipe 235. The heat generated in the primary combustion chamber 212 and the secondary combustion chamber 216 promotes the reforming reaction in the reforming chamber 214 and heats the fuel cell stack 100. The auxiliary device 200 corresponds to the heat source in the claims.

  As described above (see FIGS. 1, 6 and 7), in the present embodiment, one side of the outer periphery of the fuel cell stack 100 around the Z-axis direction (X-axis of two sides parallel to the Y-axis) One of the two communication holes 108 located in the vicinity of the side in the forward direction functions as an oxidant gas supply manifold 161, and the other of the two communication holes 108 serves as a fuel gas discharge manifold 172. Function. In addition, one of the two communication holes 108 located in the vicinity of the side opposite to the side (the side on the X-axis negative direction side of the two sides parallel to the Y axis) is an oxidant gas discharge manifold The other of the two communication holes 108 functions as a fuel gas supply manifold 171. That is, as viewed in the Z-axis direction, the oxidant gas supply manifold 161 and the fuel gas discharge manifold 172 are positioned near one short side of the rectangular shape of the fuel cell stack 100, and the oxidant gas discharge manifold 162 and the fuel gas supply The manifold 171 is located near the other short side of the rectangle. In other words, as viewed in the Z-axis direction, the fuel gas supply manifold 171 is disposed at a position facing the oxidant gas supply manifold 161 across the unit cell 110, and the fuel gas discharge manifold 172 It is disposed at a position opposed to the oxidant gas discharge manifold 162 with the spacer interposed therebetween. Therefore, the main flow direction of the oxidant gas OG in the air chamber 166 of each power generation unit 102 is a direction from the X-axis positive direction to the X-axis negative direction as shown in FIG. As shown in FIG. 7, the main flow direction of is the direction from the X-axis negative direction side to the X-axis positive direction side. As described above, the fuel cell stack 100 according to the present embodiment is a so-called counterflow type SOFC in which the main flow direction of the oxidant gas OG and the main flow direction of the fuel gas FG face each other.

A-3. Positional relationship between fuel cell stack 100 and auxiliary device 200:
The power generation module 20 of the present embodiment is characterized in the positional relationship between the fuel cell stack 100 and the auxiliary device 200. Specifically, as shown in FIGS. 1 to 3, the auxiliary device 200 overlaps with all the unit cells 110 included in the fuel cell stack 100 in a direction view (a plane direction view) orthogonal to the Z axis. It is arranged.

  Further, FIG. 6 shows the smallest virtual rectangle VR circumscribing the outer shape of the fuel cell stack 100 in the Z-axis direction. In the power generation module 20 of the present embodiment, since the outer shape of the fuel cell stack 100 is a rectangle, the virtual rectangle VR matches the outer shape of the fuel cell stack 100. That is, the virtual rectangle VR is a rectangle having a side parallel to the X-axis direction as a long side and a side parallel to the Y-axis direction as a short side, and the length of the long side of the rectangle is 150 mm or more.

  Further, among the four virtual sides VS (VS1 to VS4) constituting the virtual rectangle VR, the virtual side VS closest to the centroid P1 of the oxidant gas supply manifold 161 is referred to as a specific virtual side SVS. In the power generation module 20 of the present embodiment, the virtual side VS2 located on the positive side in the X-axis direction of the two virtual sides VS parallel to the Y-axis becomes the specific virtual side SVS. That is, the specific virtual side SVS is a short side of the virtual rectangle VR which is a rectangle. When a plurality of oxidant gas supply manifolds 161 exist, the above-mentioned centroid P1 means the centroid of the figure formed by connecting the centroids of the respective oxidant gas supply manifolds 161 by line segments. Do. For example, when there are two oxidant gas supply manifolds 161, the aforementioned centroid P1 is the centroid of one oxidant gas supply manifold 161 and the centroid of the other oxidant gas supply manifold 161. It is the middle point of the connecting line segment.

  As shown in FIG. 6, in the power generation module 20 of the present embodiment, in the Z-axis direction, the auxiliary device 200 is in a direction orthogonal to a part of the specific virtual side SVS and the specific virtual side SVS (in the present embodiment, the X axis Facing the direction). Further, in the power generation module 20 according to the present embodiment, the auxiliary device 200 faces the entire oxidant gas supply manifold 161 in the direction orthogonal to the specific imaginary side SVS in the Z-axis direction.

A-4. Effects of the present embodiment:
As described above, the power generation module 20 according to the present embodiment includes the electrolyte layer 112 and the air electrode 114 and the fuel electrode 116 facing each other with the electrolyte layer 112 interposed therebetween, and the plurality of power generation modules 20 are arranged in the Z-axis direction. A fuel cell stack 100 having single cells 110 and an auxiliary device 200 are provided. In the fuel cell stack 100, an oxidant gas supply manifold 161 which is a gas flow path for supplying the oxidant gas OG to the air chamber 166 facing the air electrode 114 of each unit cell 110 is formed. The auxiliary device 200 overlaps all the single cells 110 included in the fuel cell stack 100 in a direction view (plane direction view) orthogonal to the Z-axis direction. In addition, the auxiliary device 200 is the most at the center P1 of the oxidant gas supply manifold 161 among the four virtual sides VS that form the smallest virtual rectangle VR circumscribing the outer shape of the fuel cell stack 100 in the Z-axis direction. A part of the specific virtual side SVS, which is the near virtual side VS, faces the direction perpendicular to the specific virtual side SVS.

  Here, since the oxidant gas OG and the fuel gas FG supplied to the fuel cell stack 100 are introduced from the outside of the fuel cell stack 100, the temperature is relatively low. In addition, when the fuel cell stack 100 is operated, the supply amount of the oxidant gas OG is set to a value larger than the supply amount of the fuel gas FG in order to enhance the utilization of hydrogen in the fuel gas FG. Be done. Therefore, the area (for example, the area X1 in FIG. 6) near the oxidant gas supply manifold 161 in each unit cell 110 included in the fuel cell stack 100 is deprived of heat by a large amount of the oxidant gas OG, and the temperature decreases. It's easy to do. When the temperature of a specific area in the single cell 110 decreases, the uniformity of the temperature distribution in the plane of the single cell 110 decreases (that is, the temperature difference between the individual areas of the single cell 110 increases). As a result, the power generation performance of the fuel cell stack 100 is reduced.

  In the power generation module 20 according to the present embodiment, as described above, the auxiliary device 200 overlaps all the unit cells 110 included in the fuel cell stack 100 in a plane direction view, and an oxidant in the Z axis direction view. A portion of the specific imaginary side SVS close to the center P1 of the gas supply manifold 161 is opposed in the direction orthogonal to the specific imaginary side SVS. Therefore, according to the power generation module 20 of the present embodiment, the heat generated from the auxiliary device 200 suppresses the temperature drop of the region near the oxidant gas supply manifold 161 in all the single cells 110 included in the fuel cell stack 100. be able to. Therefore, according to the power generation module 20 of the present embodiment, it is possible to suppress the decrease in the uniformity of the temperature distribution in the plane in all the single cells 110 included in the fuel cell stack 100, and as a result, the fuel cell stack 100 It is possible to suppress the decrease in the power generation performance of

  In the power generation module 20 according to the present embodiment, the outer shape of the fuel cell stack 100 is a linear shape in which at least a part thereof faces the single cell 110 across the center P1 of the oxidant gas supply manifold 161 in the Z-axis direction. It has at least one side. Therefore, the auxiliary device 200 opposes at least a part of the side closest to the center P1 of the oxidant gas supply manifold 161 in the straight side in the direction orthogonal to the side. Therefore, according to the power generation module 20 of the present embodiment, it is possible to effectively reduce the temperature of the region near the oxidant gas supply manifold 161 in each unit cell 110 included in the fuel cell stack 100 by the heat generated from the auxiliary device 200. By suppressing this, it is possible to more effectively suppress the decrease in the uniformity of the in-plane temperature distribution, and as a result, the decrease in the power generation performance of the fuel cell stack 100 can be suppressed more effectively.

  Further, in the power generation module 20 according to the present embodiment, the fuel cell stack 100 in the Z-axis direction has a rectangular shape having a side parallel to the X-axis direction as a long side and a side parallel to the Y-axis direction as a short side. is there. Therefore, the virtual rectangle VR is also a rectangle. Further, in the power generation module 20 of the present embodiment, the specific virtual side SVS that is the virtual side VS closest to the center P1 of the oxidant gas supply manifold 161 is the short side of the virtual rectangle VR that is rectangular. Therefore, in the power generation module 20 of the present embodiment, the uniformity of the temperature distribution in the plane of the unit cell 110 is likely to be degraded, and as a result, it can be said that the power generation performance of the fuel cell stack 100 is likely to be degraded. According to the power generation module 20 of the present embodiment, even in the configuration in which the power generation performance of the fuel cell stack 100 tends to decrease, the heat generated from the auxiliary device 200 causes the oxidant gas supply manifold 161 in each unit cell 110 to By suppressing the temperature decrease in the near region, it is possible to suppress the decrease in the uniformity of the in-plane temperature distribution, and as a result, the decrease in the power generation performance of the fuel cell stack 100 can be suppressed.

  Further, in the power generation module 20 of the present embodiment, the length of the long side of the rectangle which is the shape of the fuel cell stack 100 in the Z-axis direction is 150 mm or more. Therefore, the length of the long side of the rectangular virtual rectangle VR is also 150 mm or more. As described above, in the power generation module 20 according to the present embodiment, the long side of the virtual rectangle VR is long to some extent, so the uniformity of the temperature distribution in the plane of the unit cell 110 is further easily degraded. It can be said that the power generation performance is likely to be further reduced. According to the power generation module 20 of the present embodiment, the oxidant gas supply manifold 161 in each unit cell 110 is generated by the heat generated from the auxiliary unit 200 even in the configuration in which the power generation performance of the fuel cell stack 100 is easily reduced. By suppressing the temperature decrease in the region near the point, it is possible to suppress the decrease in the uniformity of the in-plane temperature distribution, and as a result, the decrease in the power generation performance of the fuel cell stack 100 can be suppressed. Note that the present invention is more preferable in a configuration in which the long side of the virtual rectangle VR is 160 mm or more in that the uniformity of the temperature distribution in the plane of the single cell 110 is likely to be reduced. The long side of the virtual rectangle VR is more preferably 170 mm or more, and the long side of the virtual rectangle VR is more preferably 180 mm or more, and the long side of the virtual rectangle VR is 190 mm. It is extremely preferable in the above configuration, and most preferable in a configuration in which the long side of the virtual rectangle VR is 200 mm or more. Further, the present invention is suitable in a configuration in which the length of the long side of the virtual rectangle VR is 500 mm or less.

  Further, in the power generation module 20 of the present embodiment, the fuel cell stack 100 further includes a fuel gas supply that is a gas flow path for supplying the fuel gas FG to the fuel chamber 176 facing the fuel electrode 116 of each unit cell 110. A manifold 171 is formed. The fuel gas supply manifold 171 is disposed at a position facing the oxidant gas supply manifold 161 across the unit cell 110 as viewed in the Z-axis direction. As described above, in the power generation module 20 of the present embodiment, the configuration of the counter flow type is adopted 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 face each other. ing. In the configuration of the counter flow type, power generation tends to be concentrated and the temperature is likely to rise in a region near the fuel gas supply manifold 171 in each unit cell 110 (for example, region X2 in FIG. 6). It can be said that the uniformity of the temperature distribution of is more likely to be degraded. According to the power generation module 20 of the present embodiment, the oxidant gas supply manifold 161 in each unit cell 110 is generated by the heat generated from the auxiliary unit 200 even in the configuration in which the power generation performance of the fuel cell stack 100 is easily reduced. By suppressing the temperature decrease in the region near the point, it is possible to suppress the decrease in the uniformity of the in-plane temperature distribution, and as a result, the decrease in the power generation performance of the fuel cell stack 100 can be suppressed.

  Further, in the power generation module 20 according to the present embodiment, the auxiliary device 200 is opposed to the entire oxidant gas supply manifold 161 in the direction orthogonal to the specific imaginary side SVS in the Z-axis direction. Therefore, in the power generation module 20 of the present embodiment, the heat generated from the auxiliary device 200 extremely effectively suppresses the temperature decrease of the region near the oxidant gas supply manifold 161 in each unit cell 110, thereby achieving the in-plane. It is possible to extremely effectively suppress the decrease in the uniformity of the temperature distribution of Therefore, according to the power generation module 20 of the present embodiment, the decrease in the power generation performance of the fuel cell stack 100 can be extremely effectively suppressed.

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.

  The configuration of the power generation module 20 according to the above-described embodiment is merely an example, and can be variously modified. For example, in the above embodiment, the auxiliary device 200 is disposed so as to overlap all the single cells 110 included in the fuel cell stack 100 in a direction view (plane direction view) orthogonal to the Z axis. As in the power generation module 20 of the modified example, the auxiliary device 200 may be disposed so as to overlap only with some of the power generation units 102 (single cells 110) included in the fuel cell stack 100 in a plane direction view. . Also in the power generation module 20 having such a configuration, as in the above embodiment, if the auxiliary device 200 faces the specific virtual side SVS in the direction orthogonal to the specific virtual side SVS in the Z-axis direction, The heat generated from the heater 200 can suppress a temperature drop in a region near the oxidant gas supply manifold 161 in each unit cell 110 overlapping the auxiliary device 200 mainly in a plane direction, and the in-plane temperature distribution is uniform. It is possible to suppress the decrease in the conductivity, and as a result, it is possible to suppress the decrease in the power generation performance of the fuel cell stack 100. As described above, when at least a part of the auxiliary device 200 overlaps the at least one single cell 110 in a plane direction view, the same effect as the above embodiment can be obtained.

  Further, in the above embodiment, the auxiliary device 200 is opposed to the entire oxidant gas supply manifold 161 in the direction orthogonal to the specific virtual side SVS in the Z-axis direction, but in the modification shown in FIG. As in the power generation module 20, the auxiliary device 200 may face only a part of the oxidant gas supply manifold 161 in the direction orthogonal to the specific imaginary side SVS in the Z-axis direction. Further, as in the power generation module 20 of the modified example shown in FIG. 10, even if the auxiliary device 200 does not face the oxidant gas supply manifold 161 in the direction orthogonal to the specific imaginary side SVS in the Z-axis direction. Good. Also in the power generation module 20 of these configurations, as in the above embodiment, if the auxiliary device 200 faces the specific virtual side SVS in the direction orthogonal to the specific virtual side SVS in the Z-axis direction, the auxiliary device The heat generated from 200 can suppress the temperature decrease of the region near the oxidant gas supply manifold 161 in the single cell 110, and can suppress the decrease in the uniformity of the in-plane temperature distribution, as a result. The deterioration of the power generation performance of the fuel cell stack 100 can be suppressed. As described above, when at least a part of the assisting device 200 faces at least a part of the specific virtual side SVS in a direction orthogonal to the specific virtual side SVS in the Z-axis direction, the same effect as the above embodiment is obtained. can get.

  In the above embodiment, the shape of the fuel cell stack 100 in the Z-axis direction is a rectangle having a side parallel to the X-axis direction as a long side and a side parallel to the Y-axis direction as a short side. It does not necessarily have to be such a shape. For example, the shape of the fuel cell stack 100 as viewed in the Z-axis direction may be a rectangle having a side parallel to the X-axis direction as a short side and a side parallel to the Y-axis direction as a long side. May be Further, the shape of the fuel cell stack 100 in the Z-axis direction may be a shape in which corner portions of a rectangle or a square are chamfered (R-chamfered or C-chamfered). Further, the shape of the fuel cell stack 100 in the Z-axis direction is not limited to a rectangle, and may be another shape such as a substantially elliptical shape or a polygon having five or more sides. FIG. 11 shows a modified power generation module 20 in which the shape of the fuel cell stack 100 in the Z-axis direction is substantially elliptical. Further, FIG. 12 shows a modified power generation module 20 in which the shape of the fuel cell stack 100 in a Z-axis direction is a dodecagon. Also in the power generation module 20 of these configurations, as in the above embodiment, if the auxiliary device 200 faces the specific virtual side SVS in the direction orthogonal to the specific virtual side SVS in the Z-axis direction, the auxiliary device The heat generated from 200 can suppress the temperature decrease of the region near the oxidant gas supply manifold 161 in the single cell 110, and can suppress the decrease in the uniformity of the in-plane temperature distribution, as a result. The deterioration of the power generation performance of the fuel cell stack 100 can be suppressed.

  In the above embodiment, the long side of the long side of the rectangular shape of the fuel cell stack 100 in the Z-axis direction is 150 mm or more, but the size of the fuel cell stack 100 in the Z-axis direction is It can be changed arbitrarily.

  Further, in the above embodiment, as the configuration relating to the gas flow of the fuel cell stack 100, a configuration of a counterflow type is adopted in which the main flow direction of the oxidant gas OG and the main flow direction of the fuel gas FG face each other. However, in the present invention, the main flow direction of the oxidant gas OG and the main flow direction of the fuel gas FG are substantially the same, or the main flow direction of the oxidant gas OG and the fuel gas FG The present invention can be similarly applied to a cross flow type configuration in which the main flow directions of and are substantially orthogonal to each other.

  Further, in the above embodiment, the primary combustion chamber 212, the reforming chamber 214 and the secondary combustion chamber 216 are formed in the auxiliary device 200, but the number of combustion chambers formed in the auxiliary device 200 is one. There may be one or three or more. Further, the reforming chamber 214 may not be formed in the auxiliary device 200.

  In the above embodiment, although the power generation module 20 includes the auxiliary 200 as a heat source, the power generation module 20 includes another heat source instead of or in addition to the auxiliary 200. It may be Even in such a configuration, if the relationship between the fuel cell stack 100 and the heat source is similar to the relationship between the fuel cell stack 100 and the auxiliary device 200 in the above embodiment, each single cell 110 is generated by the heat generated from the heat source. The temperature decrease of the region near the oxidant gas supply manifold 161 in the case can be suppressed, and the decrease in the uniformity of the in-plane temperature distribution can be suppressed, and as a result, the power generation performance of the fuel cell stack 100 decreases. Can be suppressed.

  Further, in the above embodiment, although the bolt holes 109 are provided independently of the communication holes 108 for each manifold, the bolt holes 109 are not provided independently, and a part of the communication holes 108 for each manifold or The whole may be used as a bolt hole. 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 power generation units 102 (unit cells 110) included in the fuel cell stack 100 is merely an example, and the number of power generation units 102 is in accordance with the output voltage etc. required of the fuel cell stack 100. Are determined accordingly. 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.

 Moreover, in the said embodiment, although the solid oxide fuel cell (SOFC) was demonstrated to the example, this invention is applicable also to the fuel cell of another type. The present invention is suitable for a high temperature fuel cell such as SOFC or a molten carbonate fuel cell (MCFC).

20: fuel cell power generation module 22: bolt 26: insulation sheet 27: gas passage member 100: fuel cell stack 102: fuel cell power generation unit 104: end plate 106: end plate 107: passage through hole 108: communication hole 109: communication hole Bolt hole 110: single cell 112: electrolyte layer 114: air electrode 116: fuel electrode 120: separator 121: hole 124: joint portion 130: air electrode side frame 131: hole 132: oxidant gas supply communication flow path 133: oxidant Gas discharge communication channel 134: Air electrode side current collector 135: Current collector element 140: Fuel electrode side frame 141: Hole 142: Fuel gas supply communication channel 143: Fuel gas discharge communication channel 144: Fuel electrode side collector Current collector 145: electrode facing portion 146: interconnector facing portion 147: connection portion 149: Spacer 150: Interconnector 161: Oxidant gas supply manifold 162: Oxidant gas discharge manifold 166: Air chamber 171: Fuel gas supply manifold 172: Fuel gas discharge manifold 176: Fuel chamber 200: Auxiliary device 212: Primary combustion chamber 214: reforming chamber 216: secondary combustion chamber 218: gas flow path 222: partition 231: first pipe 232: second pipe 233: third pipe 234: fourth pipe 235: fifth pipe 236 : Sixth piping 237: Seventh piping

Claims (9)

A fuel cell stack including a plurality of unit cells, each including an electrolyte layer and an air electrode and a fuel electrode facing each other with the electrolyte layer interposed therebetween, and arranged in a first direction;
A heat source,
In a fuel cell power generation module comprising
The fuel cell stack is formed with an oxidant gas supply manifold which is a gas flow path for supplying oxidant gas to an air chamber facing the air electrode of each unit cell,
At least a portion of the heat source is
Overlap with at least one of the single cells in a direction orthogonal to the first direction, and
Of the four virtual sides forming the smallest virtual rectangle circumscribing the outer shape of the fuel cell stack in the first direction, a specific virtual that is the virtual side closest to the center of the oxidant gas supply manifold. A fuel cell power generation module, characterized in that at least a part of the side faces in a direction orthogonal to the specific virtual side. In the fuel cell power generation module according to claim 1,
As viewed in the first direction, the outer shape of the fuel cell stack is characterized in that at least a portion has at least one linear side facing the single cell across the center of the oxidant gas supply manifold. A fuel cell power generation module. The fuel cell power generation module according to claim 1 or 2,
The virtual rectangle is a rectangle,
The fuel cell power generation module according to claim 1, wherein the specific imaginary side is a short side of the rectangle. In the fuel cell power generation module according to claim 3,
The fuel cell power generation module, wherein a length of a long side of the rectangle is 150 mm or more. The fuel cell power generation module according to any one of claims 1 to 4.
The fuel cell stack further includes a gas flow path for supplying a fuel gas to a fuel chamber facing the fuel electrode of each unit cell, and the unit cell is interposed between the unit cells in the first direction view. What is claimed is: 1. A fuel cell power generation module comprising: a fuel gas supply manifold disposed at a position opposite to an oxidant gas supply manifold. The fuel cell power generation module according to any one of claims 1 to 5,
A fuel cell power generation module, wherein at least a portion of the heat source is opposed to at least a portion of the oxidant gas supply manifold in a direction orthogonal to the specific imaginary side in the first direction. In the fuel cell power generation module according to claim 6,
A fuel cell power generation module, wherein at least a part of the heat source faces the whole of the oxidant gas supply manifold in a direction orthogonal to the specific imaginary side in the first direction. The fuel cell power generation module according to any one of claims 1 to 7.
A fuel cell power generation module, wherein at least a part of the heat source overlaps all the unit cells included in the fuel cell stack in a direction perpendicular to the first direction. The fuel cell power generation module according to any one of claims 1 to 8.
The fuel cell power generation module according to claim 1, wherein the heat source includes an auxiliary unit having a combustion chamber configured to burn the gas discharged from the fuel cell stack.

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