Electrochemical reaction module

Abstract

To suppress heat transfer through a support member in an electrochemical reaction module.SOLUTION: An electrochemical reaction module includes an electrochemical reaction cell stack, a container, a first heat insulating material and a support member. A least one of gas supplied to the electrochemical reaction cell stack and gas discharged from the electrochemical reaction cell stack circulates in the container. The first heat insulating material may be deformed by external force. The first heat insulating material is disposed below and adjacent to a supported object that is one of the electrochemical reaction cell stack and the container, and includes at least one hole formed therein. The support member can support the supported object and is disposed inside the hole. At least one of the first heat insulating material and a second heat insulating material disposed inside the hole is located at least one of above and below the support member.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The technology disclosed herein relates to an electrochemical reaction module. [Background technology]

[0002] A solid oxide fuel cell (hereinafter referred to as "SOFC") is known as a type of fuel cell that generates electricity by utilizing an electrochemical reaction between hydrogen and oxygen. A fuel cell module is also known as one application form of SOFC.

[0003] A known fuel cell module comprises a cell stack device (supported object), a deformable first insulating material having a mounting surface on which the cell stack device is placed, and a support member disposed within the first insulating material and capable of supporting the cell stack device (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6960456 Summary of the Invention [Problem to be solved by the invention]

[0005] The above fuel cell module has a problem in that heat transfer occurs via the support member, and the temperature of the supported member is likely to decrease.

[0006] These issues are also common to electrolysis modules, which are a type of electrolysis cell (hereinafter referred to as "SOEC") that generates hydrogen using the electrolysis reaction of water. A fuel cell stack and an electrolysis cell stack are collectively referred to as an electrochemical reaction cell stack, and a fuel cell module and an electrolysis module are collectively referred to as an electrochemical reaction module. These issues are not limited to SOFCs and SOECs, but are also common to other types of fuel cells and electrolysis cells.

[0007] This specification discloses a technique that can solve the above-mentioned problems. [Means for solving the problem]

[0008] The technology disclosed in this specification can be realized, for example, in the following forms.

[0009] (1) The electrochemical reaction module disclosed in this specification includes an electrochemical reaction cell stack, a container, a first insulating material, and a support member. At least one of a gas supplied to the electrochemical reaction cell stack and a gas discharged from the electrochemical reaction cell stack flows through the container. The first insulating material is deformable by an external force. The first insulating material is disposed adjacent to and below a supported object, which is one of the electrochemical reaction cell stack and the container, and has at least one hole formed therein. The support member is capable of supporting the supported object and is disposed inside the hole. At least one of the first insulating material and a second insulating material disposed inside the hole is located above and below the support member.

[0010] According to this electrochemical reaction module, at least one of a first insulating material and a second insulating material is located above or below the support member, thereby suppressing heat transfer through the support member and preventing a decrease in the temperature of the supported object.

[0011] (2) In the electrochemical reaction module, the first insulating material may be disposed between the electrochemical reaction cell stack and the container, which are arranged vertically side by side, the hole may penetrate vertically, and the second insulating material may be located above and below the support member. With this configuration, since the second insulating materials are located above and below the support member, heat transfer between the electrochemical reaction cell stack and the container via the support member can be suppressed.

[0012] (3) In the electrochemical reaction module, the area of ​​the support surface of the support member facing the supported object may be 5% or more and 50% or less of the area of ​​the supported surface of the supported object facing the support member. With this configuration, the load of the supported object can be effectively supported while effectively suppressing heat transfer through the support member.

[0013] (4) In the electrochemical reaction module, the support member may be an insulator. With this configuration, for example, even if the support member is arranged so as to contact a conductive portion in the electrochemical reaction cell stack, insulation between the support member and the electrochemical reaction cell stack can be ensured. Therefore, the degree of freedom in arranging the support member can be increased.

[0014] (5) In the electrochemical reaction module, the support member may be made of metal. By using a metal support member in this configuration, the cost of manufacturing the support member can be reduced compared to when the support member is made of, for example, a dense alumina rod.

[0015] (6) In the electrochemical reaction module, the second insulating material may be located above or below the support member, and the second insulating material may be denser than the first insulating material. With this configuration, the second insulating material is denser than the first insulating material and therefore less likely to deform than the first insulating material, thereby enabling the second insulating material to effectively support the load of the supported object.

[0016] The technology disclosed in this specification can be realized in various forms, for example, in the form of an electrochemical reaction module and a manufacturing method thereof. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is an explanatory diagram illustrating the configuration of a fuel cell module 10. [Figure 2]FIG. 1 is a perspective view showing the external configuration of a fuel cell stack 100. [Figure 3] FIG. 3 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 taken along the line III-III in FIG. 2. [Figure 4] 4 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 taken along the line IV-IV in FIG. 2. [Figure 5] FIG. 3 is an explanatory diagram showing the YZ cross-sectional configuration of the fuel cell stack 100 at the position VV in FIG. 2. [Figure 6] An explanatory diagram showing the XZ cross-sectional structure of two adjacent reaction units 101U at the same position as the cross-section shown in FIG. [Figure 7] FIG. 5 is an explanatory diagram showing the XZ cross-sectional structure of two adjacent reaction units 101U at the same position as the cross-section shown in FIG. [Figure 8] FIG. 1 is an explanatory diagram showing a cross-sectional configuration of a fuel cell module 10. [Figure 9] FIG. 1 is an explanatory diagram showing an enlarged cross section of a fuel cell module 10 according to a first embodiment. [Figure 10] FIG. 10 is an explanatory diagram showing an enlarged cross section of a fuel cell module 10a according to a second embodiment. [Figure 11] FIG. 10 is an explanatory diagram showing an enlarged cross section of a fuel cell module 10b according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] A. First embodiment: A-1. Configuration of fuel cell module 10: Figure 1 is an explanatory diagram that schematically shows the configuration of a fuel cell module 10. Figure 1 and the following figures show mutually orthogonal X, Y, and Z axes for specifying directions. For convenience, in this specification, the Y-axis direction will be referred to as the up-down direction, the positive Y-axis direction will be referred to as the upward direction, and the negative Y-axis direction will be referred to as the downward direction.

[0019] The fuel cell module 10 includes a fuel cell stack 100, an auxiliary device 400 provided outside the fuel cell stack 100, a plurality of pipes, and a first heat insulating material 510. Below, the configuration of the fuel cell stack 100 will be described first, and then the configurations of devices other than the fuel cell stack 100 will be described. The fuel cell module 10 is an example of an electrochemical reaction module. The fuel cell stack 100 is an example of an electrochemical reaction cell stack.

[0020] A-2. Configuration of fuel cell stack 100: 2 is an oblique view showing the external configuration of the fuel cell stack 100, FIG. 3 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position III-III in FIG. 2, FIG. 4 is an explanatory diagram showing the XZ cross-sectional configuration of the fuel cell stack 100 at the position IV-IV in FIG. 2, and FIG. 5 is an explanatory diagram showing the YZ cross-sectional configuration of the fuel cell stack 100 at the position VV in FIG. 2.

[0021] (Overall configuration of fuel cell stack 100) 2 to 5, the fuel cell stack 100 includes a power generation block 101, a first end plate 210, an insulating section 220, an end separator 230, a first plate 232, a first terminal plate 240, a second terminal plate 250, a second plate 260, a second end plate 270, and four gas passage members 280. The first end plate 210, the insulating section 220, the end separator 230, the first terminal plate 240, the power generation block 101, the second terminal plate 250, the second plate 260, and the second end plate 270 have rectangular outer shapes of approximately the same size and are arranged in this order, stacked in a predetermined arrangement direction (the Z-axis direction).

[0022] As shown in Figures 2 and 5, the fuel cell stack 100 has bolt holes BH near each of the four corners that penetrate from the first end plate 210 to the second end plate 270. A bolt B is inserted into each bolt hole BH. A nut N is screwed onto both ends of each bolt B. These bolts B and nuts N fasten the members from the first end plate 210 to the second end plate 270 together. As shown in Figures 3 to 5, the first plate 232 is supported by the terminal separator 230, and the four gas passage members 280 are connected to the second end plate 270.

[0023] (Power Generation Block 101) 3 to 5, the power generation block 101 is composed of a plurality of (seven in this embodiment) reaction units 101U arranged side by side in a predetermined arrangement direction (Z-axis direction). Details of the reaction units 101U will be described later.

[0024] (First end plate 210) The first end plate 210 is a member formed by pressing (bending) a single plate-like member, and is formed of a conductive material such as stainless steel. As shown in FIGS. 2 to 5 , the first end plate 210 includes a rectangular, frame-like flat portion 211 having a through-hole 212 near the center, and an outer convex portion 213 and an inner convex portion 214 that protrude from the flat portion 211 in the direction opposite to the insulating portion 220 (the positive Z-axis direction). The flat portion 211 has holes that form the bolt holes BH described above. The outer convex portion 213 protrudes from the outer periphery of the flat portion 211. The outer convex portion 213 is formed around the entire outer periphery of the flat portion 211. The inner convex portion 214 protrudes from the inner periphery of the flat portion 211. The inner convex portion 214 is formed around the entire inner periphery of the flat portion 211.

[0025] (insulating part 220) Insulating section 220 is a rectangular frame-shaped member with a through-hole near the center, and is made of, for example, an insulating material. As shown in Fig. 3, insulating section 220 is sandwiched between first end plate 210 and end separator 230, thereby ensuring insulation between first end plate 210 and end separator 230.

[0026] (Terminal separator 230) As shown in FIGS. 3 to 5, the terminal separator 230 is a rectangular frame-shaped member having a through-hole 231 near the center, and is made of, for example, metal.

[0027] (First Plate 232) The first plate 232 is a rectangular, flat member made of a conductive material such as stainless steel. As shown in Figures 3 to 5, the first plate 232 is joined, for example, by welding, to the peripheral portion of the through-hole 231 in the terminal separator 230. The terminal separator 230 and the first plate 232 separate the power generation block 101 from the external space of the fuel cell stack 100.

[0028] The first plate 232 is connected to an interconnector 190 (described later) provided in a reaction unit 101U arranged at one end (the end on the positive Z-axis direction side) of the multiple reaction units 101U that make up the power generation block 101, via a connecting member having the same structure as an anode current collecting member 144 (described later). This electrically connects the reaction unit 101U and the first plate 232.

[0029] (First terminal plate 240) The first terminal plate 240 is a rectangular frame-shaped member having a through-hole 241 near the center, and is made of a conductive material such as ferritic stainless steel, which has an alumina oxide coating formed on its surface. The first terminal plate 240 is electrically connected to a reaction unit 101U arranged at one end (the end on the positive Z-axis direction) of the multiple reaction units 101U that make up the power generation block 101, via a first plate 232 and a terminal separator 230. One end (the end on the positive X-axis direction) of the first terminal plate 240 protrudes from the power generation block 101, and this protruding portion functions as a positive output terminal for the fuel cell stack 100.

[0030] (2nd terminal plate 250) The second terminal plate 250 is a rectangular plate-shaped member made of a conductive material such as ferritic stainless steel that forms an alumina oxide coating on its surface. The second terminal plate 250 is electrically connected to the reaction unit 101U that is located at the other end (the end on the negative Z-axis direction) of the multiple reaction units 101U that make up the power generation block 101. One end (the end on the positive X-axis direction) of the second terminal plate 250 protrudes from the power generation block 101, and this protruding portion functions as the negative output terminal of the fuel cell stack 100.

[0031] (Second plate 260) Second plate 260 is a rectangular, flat member made of, for example, an insulating material. The peripheral edge of second plate 260 is sandwiched between second terminal plate 250 and second end plate 270, thereby ensuring insulation between second terminal plate 250 and second end plate 270.

[0032] (Second end plate 270) The second end plate 270 is a member formed by pressing (bending) a single plate-like member, and is formed of a conductive material such as stainless steel. The second end plate 270 includes a rectangular, frame-like flat portion 271 having a through-hole 272 near the center, and an outer convex portion 273 and an inner convex portion 274 that protrude from the flat portion 271 in the direction opposite to the second terminal plate 250 (the negative Z-axis direction). The flat portion 271 has holes that form the bolt holes BH described above. The outer convex portion 273 protrudes from the outer periphery of the flat portion 271. The outer convex portion 273 is formed around the entire outer periphery of the flat portion 271. The inner convex portion 274 protrudes from the inner periphery of the flat portion 271. The inner convex portion 274 is formed around the entire inner periphery of the flat portion 271.

[0033] (Manifolds 311, 312, 321, 322) 2, 3, and 4, the fuel cell stack 100 has four holes that penetrate from the power generation block 101 to the second end plate 270. The four holes are an oxidant gas supply manifold 311, an oxidant gas discharge manifold 312, a fuel gas supply manifold 321, and a fuel gas discharge manifold 322, respectively.

[0034] 3, the oxidant gas supply manifold 311 is a gas flow path that supplies an oxidant gas OG introduced from outside the fuel cell stack 100 to an air chamber 313 (described later) of each reaction unit 101U. The oxidant gas discharge manifold 312 is a gas flow path that discharges an oxidant off-gas OOG discharged from the air chamber 313 of each reaction unit 101U to the outside of the fuel cell stack 100. Air, for example, is used as the oxidant gas OG. The oxidant gas supply manifold 311 and the oxidant gas discharge manifold 312 are arranged on opposite sides of the air chamber 313.

[0035] As shown in Fig. 4, the fuel gas supply manifold 321 is a gas flow path that supplies fuel gas FG introduced from outside the fuel cell stack 100 to a fuel chamber 323 (described later) of each reaction unit 101U. The fuel gas discharge manifold 322 is a gas flow path that discharges fuel off-gas FOG discharged from the fuel chamber 323 of each reaction unit 101U to the outside of the fuel cell stack 100. For example, hydrogen-rich gas obtained by reforming city gas is used as the fuel gas FG. The fuel gas supply manifold 321 and the fuel gas discharge manifold 322 are arranged on opposite sides of the fuel chamber 323.

[0036] (Gas passage member 280) As shown in FIGS. 2 to 4 , each of the four gas passage members 280 includes a main body portion 281 and a flange portion 282. The main body portion 281 has a gas through hole 283 formed therethrough in the vertical direction. The flange portion 282 is provided so as to protrude outward from the other end (the end on the negative Z-axis direction side) of the main body portion 281. The flange portion 282 has a plurality of bolt holes 284. A bolt (not shown) for connecting the fuel cell stack 100 to an external device is inserted into each bolt hole 284. One end (the end on the positive Z-axis direction side) of the main body portion 281 included in each of the four gas passage members 280 is joined to the second end plate 270 by, for example, welding. The gas through hole 283 is connected to the manifolds 311, 312, 321, and 322, respectively. A gas pipe (not shown) for supplying or discharging gas is connected to each of the main body portions 281.

[0037] (Overall composition of 101U reaction units) FIG. 6 is an explanatory diagram showing the XZ cross-sectional structure of two adjacent reaction units 101U at the same position as the cross-section shown in FIG. 3. FIG. 7 is an explanatory diagram showing the XZ cross-sectional structure of two adjacent reaction units 101U at the same position as the cross-section shown in FIG. 4. As shown in FIGS. 6 and 7, the reaction unit 101U includes a single cell 110, a single cell separator 120, an air electrode frame 130, an anode frame 140, an anode current collecting member 144, two interconnectors 190, and two IC separators 180. One IC separator 180, the air electrode frame 130, the single cell separator 120, the anode frame 140, and the other IC separator 180 are stacked in this order. The single cell 110 is supported by the single cell separator 120. The interconnector 190 is supported by the IC separator 180. The anode current collecting member 144 is disposed between the unit cell 110 and the interconnector 190 .

[0038] 6 and 7, the IC separator 180 and the interconnector 190 are shared by two adjacent reaction units 101U. However, as shown in Fig. 3, the reaction unit 101U located at the other end (negative Z-axis direction side) of the multiple reaction units 101U does not have the IC separator 180 and interconnector 190 adjacent to the fuel electrode frame 140, and the second terminal plate 250 overlaps the fuel electrode frame 140.

[0039] (single cell 110) The unit cell 110 includes an electrolyte layer 112, a cathode 114, an anode 116, and a reaction prevention layer 118. As shown in Figures 6 and 7, the cathode 114, the reaction prevention layer 118, the electrolyte layer 112, and the anode 116 are stacked in this order. The unit cell 110 of this embodiment is an anode-supported unit cell in which the anode 116 supports the other layers (electrolyte layer 112, air electrode 114, and reaction prevention layer 118) that make up the unit cell 110.

[0040] The electrolyte layer 112 is a rectangular, flat member. The electrolyte layer 112 has one surface (the surface on the positive side of the Z axis) on which the air electrode 114 is disposed and another surface (the surface on the negative side of the Z axis) parallel to the first surface on which the anode 116 is disposed. The electrolyte layer 112 is a layer containing a solid oxide (e.g., YSZ (yttria-stabilized zirconia)). The air electrode 114 is a layer having a rectangular shape smaller than that of the electrolyte layer 112. The air electrode 114 contains, for example, a perovskite-type oxide (e.g., LSCF (lanthanum strontium cobalt iron oxide)). The anode 116 is a layer having a rectangular shape and approximately the same size as the electrolyte layer 112. The anode 116 contains, for example, Ni (nickel), a cermet made of Ni and ceramic particles, a Ni-based alloy, or the like. The reaction prevention layer 118 is a layer having a rectangular shape and approximately the same size as the air electrode 114. The reaction prevention layer 118 includes, for example, GDC (gadolinium-doped ceria) and has the function of suppressing the reaction of an element (for example, Sr) diffused from the cathode 114 with an element (for example, Zr) contained in the electrolyte layer 112, resulting in the generation of a highly resistive substance (for example, SrZrO).

[0041] (Single cell separator 120) As shown in Figures 6 and 7, the single cell separator 120 is a rectangular frame-shaped member having a substantially rectangular through-hole 121 near the center. The single cell separator 120 is made of, for example, metal. The peripheral edge of the through-hole 121 in the single cell separator 120 is joined to the peripheral edge of one surface of the electrolyte layer 112 (the surface on which the air electrode 114 is arranged: the surface on the positive Z-axis direction) by a joint 124. The joint 124 is made of, for example, a brazing material (Ag brazing).

[0042] (Air electrode frame 130) 6 and 7, the air electrode frame 130 is a rectangular frame-like member having a substantially rectangular through-hole 131 near the center. The air electrode frame 130 is made of, for example, mica. As shown in FIG. 6, the air electrode frame 130 has an oxidant gas supply communicating channel 132 that connects the oxidant gas supply manifold 311 and the air chamber 313, and an oxidant gas discharge communicating channel 133 that connects the air chamber 313 and the oxidant gas discharge manifold 312.

[0043] (fuel electrode frame 140) 6 and 7, the anode frame 140 is a rectangular frame-like member having a substantially rectangular through-hole 141 near the center. The anode frame 140 is made of, for example, metal. As shown in FIG. 7, the anode frame 140 has a fuel gas supply communication channel 142 that connects the fuel gas supply manifold 321 and the fuel chamber 323, and a fuel gas discharge communication channel 143 that connects the fuel chamber 323 and the fuel gas discharge manifold 322.

[0044] (IC separator 180) 6 and 7, IC separator 180 is a rectangular frame-shaped member having a through-hole 181 near the center. IC separator 180 is made of, for example, metal.

[0045] (Interconnector 190 and anode current collecting member 144) As shown in FIGS. 6 and 7 , the interconnector 190 includes a rectangular flat plate portion 191, a plurality of plate-shaped air electrode current collectors 192 protruding from one surface of the flat plate portion 191 toward the air electrode 114, and a coating layer 193. The flat plate portion 191 and the air electrode current collector 192 are electrically conductive. The flat plate portion 191 and the air electrode current collector 192 are formed of a metal (e.g., ferritic stainless steel). The coating layer 193 is electrically conductive. The coating layer 193 is disposed so as to cover the surface of the air electrode current collector 192 and the surface of the flat plate portion 191 on which the air electrode current collector 192 is not disposed. The flat plate portion 191 is joined to the periphery of the through hole 181 in the IC separator 180, for example, by welding.

[0046] The anode current collecting member 144 is a member that connects the interconnector 190 and the anode 116. The anode current collecting member 144 is formed of a conductive material such as nickel, a nickel alloy, or stainless steel. As shown in FIGS. 6 and 7 , the anode current collecting member 144 has an interconnector facing portion 146, an electrode facing portion 145 that is parallel to the interconnector facing portion 146, and a connecting portion 147 that connects the electrode facing portion 145 and the interconnector facing portion 146, and has an overall U-shape. The electrode facing portion 145 is in contact with the anode 116, and the interconnector facing portion 146 is in contact with a flat portion 191 of the interconnector 190.

[0047] As described above, the interconnector 190 is shared by two adjacent reaction units 101U. More specifically, as shown in FIGS. 6 and 7, the air electrode current collecting portion 192 is joined to the air electrode 114 of the unit cell 110 provided in one of the two adjacent reaction units 101U via a conductive bonding material 196 made of, for example, a spinel-type oxide, and is thereby electrically connected to the air electrode 114. The flat plate portion 191 is electrically connected to the anode 116 of the unit cell 110 provided in the other of the two adjacent reaction units 101U via an anode current collecting member 144. This ensures electrical continuity between the two adjacent reaction units 101U.

[0048] However, as described above, the reaction unit 101U located at the other end (the end on the negative Z-axis direction side) of the multiple reaction units 101U does not have an interconnector 190 on the fuel electrode 116 side. The fuel electrode 116 included in this reaction unit 101U is connected to the second terminal plate 250 via the fuel electrode current collecting member 144.

[0049] A spacer 149 made of, for example, mica is disposed between the electrode facing portion 145 and the interconnector facing portion 146. Therefore, the anode current collecting member 144 follows the deformation of the reaction unit 101U due to temperature cycles and fluctuations in reactant gas pressure, and good electrical connection between the anode 116 and the interconnector 190 (or second terminal plate 250) via the anode current collecting member 144 is maintained.

[0050] (Air chamber 313 and fuel chamber 323) 6 and 7, the space partitioned by the single cell separator 120, single cell 110, air electrode frame 130, IC separator 180, and interconnector 190 faces the air electrode 114 and serves as an air chamber 313 through which oxidant gas OG flows. The air electrode frame 130 partitions the entire periphery of the air chamber 313 from the external space and seals the gap between the single cell separator 120 and the IC separator 180, preventing gas from leaking from the air chamber 313 to the external space.

[0051] The space partitioned by the single cell separator 120, the single cell 110, the fuel electrode frame 140, the IC separator 180, and the interconnector 190 faces the fuel electrode 116 and forms a fuel chamber 323 through which fuel gas FG flows. The fuel electrode frame 140 partitions the entire periphery of the fuel chamber 323 from the external space, and seals the gap between the single cell separator 120 and the IC separator 180, thereby preventing gas from leaking from the fuel chamber 323 to the external space.

[0052] The single cell separator 120 separates the air chamber 313 and the fuel chamber 323, and prevents gas leakage (cross leakage) from the air electrode 114 side to the fuel electrode 116 side or from the fuel electrode 116 side to the air electrode 114 side around the single cell 110. In addition, the IC separator 180 and the interconnector 190 prevent gas leakage between adjacent reaction units 101U.

[0053] A-3. Configuration of devices other than the fuel cell stack 100 in the fuel cell module 10: (Auxiliary device 400) The auxiliary unit 400 is a device for supplying fuel gas FG obtained by reforming raw fuel gas RFG, and air as oxidant gas OG, to the fuel cell stack 100. As shown in FIG. 1, the auxiliary unit 400 is disposed above the fuel cell stack 100. As shown in FIG. 1, the auxiliary unit 400 includes a housing 410, a combustor 420 and a reformer 430 disposed inside the housing 410, and an evaporator 440 disposed above the housing 410. In FIG. 1, the flow of gases on the fuel electrode side (raw fuel gas RFG, fuel gas FG, and fuel off-gas FOG) is indicated by dashed lines, the flow of gases on the air electrode side (oxidant gas OG and oxidant off-gas OOG) is indicated by solid lines, and the flow of exhaust gas EG generated by the combustor 420 is indicated by dashed lines.

[0054] (Housing 410) 1, the housing 410 is a double container including an outer box 411 and an inner box 412 that is slightly smaller than the outer box 411 and is placed inside the outer box 411. The outer box 411 and the inner box 412 are made of, for example, metal, and are sealed box-shaped containers. As will be described later, gases supplied to the fuel cell stack 100 (i.e., oxidant gas OG and fuel gas FG) and gases discharged from the fuel cell stack 100 (i.e., oxidant off-gas OOG and fuel off-gas FOG) flow through the inside of the housing 410.

[0055] The inner box 412 accommodates a reformer 430 and a combustor 420. The space between the outer box 411 and the inner box 412 forms an air flow path 413, and heat transfer fins 414 are arranged inside the air flow path 413. The outer box 411 is connected to an air supply pipe 451 that supplies oxidant gas OG to the inside of the air flow path 413, and an oxidant gas supply pipe 452 that communicates with the oxidant gas supply manifold 311 via the gas passage member 280 and supplies the oxidant gas OG that has passed through the inside of the air flow path 413 to the fuel cell stack 100. The inner box 412 is connected to an exhaust gas relay pipe 481 that sends the exhaust gas EG generated by the combustor 420 to the evaporator 440. The housing 410 is an example of a container.

[0056] (Combustor 420) The combustor 420 is a device that mixes and combusts fuel off-gas FOG and oxidant off-gas OOG that are discharged without being used in the power generation reaction by the fuel cell stack 100, to generate exhaust gas EG, and also heats the reformer 430 and the fuel cell stack 100. A catalyst that promotes the combustion of the oxidant off-gas OOG and the fuel off-gas FOG may be disposed inside the combustor 420. An oxidant gas discharge pipe 453 that communicates with the oxidant gas discharge manifold 312 via the gas passage member 280, and a fuel gas discharge pipe 464 that communicates with the fuel gas discharge manifold 322 via the gas passage member 280 are connected to the combustor 420.

[0057] (Reformer 430) The reformer 430 is a device for reforming the raw fuel gas RFG mixed with steam supplied from the evaporator 440 to generate hydrogen-rich fuel gas FG. A catalyst for promoting the reforming reaction may be disposed inside the reformer 430. A fuel gas supply pipe 463 is connected to the reformer 430, which communicates with the fuel gas supply manifold 321 via the gas passage member 280 and supplies the fuel gas FG to the fuel cell stack 100.

[0058] (Evaporator 440) The evaporator 440 is a device that evaporates the reforming water RW to generate steam, mixes this steam with the raw fuel gas RFG, and supplies it to the reformer 430. The evaporator 440 is connected to a reforming water supply pipe 471 for introducing the reforming water RW into the interior, a raw fuel gas supply pipe 461 for introducing the raw fuel gas RFG into the interior, a mixed gas supply pipe 462 that communicates with the internal space of the reformer 430 and supplies the mixed gas from the evaporator 440 to the reformer 430, and an exhaust gas discharge pipe 482 for discharging the exhaust gas EG to the outside after being used to heat the reforming water RW.

[0059] (First insulating material 510) FIG. 8 is an explanatory diagram showing the cross-sectional configuration of the fuel cell module 10. As shown in FIG. 8, the first insulating material 510 is arranged above the housing 410, to the sides of the fuel cell stack 100, the housing 410, and the multiple pipes, and below the fuel cell stack 100. Furthermore, the first insulating material 510 is also arranged between each component, such as between the fuel cell stack 100 and the housing 410 and between the fuel cell stack 100 and each pipe. By including the first insulating material 510, the fuel cell module 10 suppresses heat transfer between the inside and outside of the first insulating material 510 and between each device constituting the fuel cell module 10. The first insulating material 510 is fixed in position by being surrounded on the outside by, for example, a container. The detailed configuration of the first insulating material 510 and its surroundings will be described later.

[0060] A-4. Detailed configuration of the first insulating material 510: FIG. 9 is an explanatory diagram showing an enlarged cross section of the fuel cell module 10 in the first embodiment. As shown in FIG. 9, the first insulating material 510 is disposed adjacent to and below the fuel cell stack 100, which is the supported member, and bears the load of the fuel cell stack 100. The first insulating material 510 has a relatively low thermal conductivity, at least lower than that of the support member 540 described below. The specific material constituting the first insulating material 510 is not particularly limited. For example, the first insulating material 510 may be made of a porous material, and therefore the first insulating material 510 may be deformed by an external force. In other words, the first insulating material 510 may be deformed by the load of the fuel cell stack 100. The first insulating material 510 also has at least one hole 512 formed therein. In the first embodiment, the hole 512 is formed in the lower surface of the first insulating material 510. The hole 512 does not penetrate in the vertical direction and has a side surface S3 and a bottom surface S4.

[0061] The fuel cell module 10 further includes a support member 540. The support member 540 is disposed inside the hole 512. The first insulating material 510 is positioned above the support member 540. The shape of the support member 540 is not particularly limited, and may be, for example, a vertically extending cylinder or prism. The vertical length of the support member 540 is approximately the same as the vertical length of the side surface S3 of the hole 512. The support member 540 is made of a material capable of supporting the load of the fuel cell stack 100. Being capable of supporting the load of the fuel cell stack 100 means, for example, that the support member 540 does not deform even when subjected to the load of the fuel cell stack 100, or that the deformation is negligible. The material of the support member 540 is, for example, a non-insulating material such as a metal, or an insulating material such as a dense alumina rod.

[0062] The support member 540 has a support surface S1, which is the surface of the support member 540 that faces the fuel cell stack 100. The area of ​​the support surface S1 is 5% or more and 50% or less of the area of ​​the supported surface S2, which is the surface of the fuel cell stack 100 that faces the support member 540.

[0063] A-5. Operation of fuel cell module 10: As shown in FIG. 1 , oxidant gas OG supplied into the air flow path 413 through the air supply pipe 451 flows through the air flow path 413 while being heated by the combustion heat generated in the combustor 420, and is then supplied to the oxidant gas supply manifold 311 through the oxidant gas supply pipe 452. Furthermore, raw fuel gas RFG (e.g., city gas) is supplied to the evaporator 440 through the raw fuel gas supply pipe 461, and reforming water RW is supplied through the reforming water supply pipe 471. Inside the evaporator 440, the reforming water RW evaporates to generate steam, which is then mixed with the raw fuel gas RFG. The raw fuel gas RFG mixed with the steam is supplied to the reformer 430 through the mixed gas supply pipe 462 and is steam reformed in the reformer 430, resulting in the generation of hydrogen-rich fuel gas FG. The generated fuel gas FG is then supplied to the fuel gas supply manifold 321 through the fuel gas supply pipe 463.

[0064] As shown in Fig. 6, the oxidant gas OG supplied to the oxidant gas supply manifold 311 is supplied to the air chamber 313 of each reaction unit 101U. As shown in Fig. 7, the fuel gas FG supplied to the fuel gas supply manifold 321 is supplied to the fuel chamber 323 of each reaction unit 101U.

[0065] When an oxidant gas OG is supplied to the air chamber 313 of each reaction unit 101U and a fuel gas FG is supplied to the fuel chamber 323 of each reaction unit 101U, power is generated in the single cell 110 through an electrochemical reaction between the oxidant gas OG and the fuel gas FG. This power generation reaction is exothermic. As described above, the interconnector 190 is shared by two adjacent reaction units 101U, and the interconnector 190 ensures electrical continuity between the two adjacent reaction units 101U. In other words, the multiple reaction units 101U included in the fuel cell stack 100 are electrically connected in series. A first terminal plate 240 is electrically connected to the reaction unit 101U located at one end (the end on the positive side of the Z axis) of the multiple reaction units 101U, and a second terminal plate 250 is electrically connected to the reaction unit 101U located at the other end (the end on the negative side of the Z axis). As a result, electrical energy generated in each reaction unit 101U is extracted from the second terminal plate 250, which functions as an output terminal of the fuel cell stack 100. Since SOFCs generate electricity at relatively high temperatures (e.g., 700°C to 1000°C), after startup, the fuel cell stack 100 may be heated by a heater (not shown) until the high temperature can be maintained using the heat generated by power generation.

[0066] The oxidant off-gas OOG discharged from the air chamber 313 of each reaction unit 101U to the oxidant gas discharge manifold 312 is supplied to the combustor 420 through the gas passage member 280 and the oxidant gas discharge pipe 453. The fuel off-gas FOG discharged from the fuel chamber 323 of each reaction unit 101U to the fuel gas discharge manifold 322 is supplied to the combustor 420 through the gas passage member 280 and the fuel gas discharge pipe 464. The oxidant off-gas OOG and the fuel off-gas FOG are mixed and burned inside the combustor 420, and the heat generated at this time is used to heat the oxidant gas OG passing through the air flow path 413 and the reformer 430. The high-temperature exhaust gas EG generated by the combustion is supplied to the evaporator 440 through the exhaust gas relay pipe 481 and is used to heat the reforming water RW to generate steam.

[0067] A-6. Advantages of this embodiment: As described above, the fuel cell module 10 of this embodiment includes the fuel cell stack 100, the housing 410, the first insulating material 510, and the support member 540. Gas supplied to the fuel cell stack 100 and gas discharged from the fuel cell stack 100 flow through the housing 410. The first insulating material 510 can be deformed by an external force. The first insulating material 510 is disposed adjacent to and below the fuel cell stack 100 as the supported object, and has at least one hole 512 formed therein. The support member 540 is capable of supporting the fuel cell stack 100 and is disposed inside the hole 512. The first insulating material 510 is located above the support member 540.

[0068] According to the fuel cell module 10 of this embodiment, the first heat insulating material 510 is located above the support member 540, thereby suppressing heat transfer through the support member 540 and suppressing a decrease in the temperature of the fuel cell stack 100.

[0069] Furthermore, in the fuel cell module 10 of this embodiment, the area of ​​the support surface S1, which is the surface of the support member 540 facing the fuel cell stack 100, is 5% or more and 50% or less of the area of ​​the supported surface S2, which is the surface of the fuel cell stack 100 facing the support member 540. According to the fuel cell module 10 of this embodiment, it is possible to effectively support the load of the fuel cell stack 100 while effectively suppressing the transfer of heat via the support member 540.

[0070] Furthermore, in the fuel cell module 10 of this embodiment, the support member 540 may be an insulator. According to the fuel cell module 10 of this embodiment, for example, by forming the holes 512 on the upper surface of the first insulating material 510, it is possible to ensure insulation between the support member 540 and the fuel cell stack 100 even if the support member 540 is arranged so as to contact a conductive portion of the fuel cell stack 100. This increases the degree of freedom in arranging the support member 540.

[0071] Furthermore, in the fuel cell module 10 of this embodiment, the support member 540 may be made of metal. According to the fuel cell module 10 of this embodiment, by making the support member 540 out of metal, the cost of manufacturing the support member 540 can be reduced compared to when the support member 540 is made of, for example, a dense alumina rod or the like.

[0072] B. Second embodiment: 10 is an explanatory diagram showing an enlarged cross section of a fuel cell module 10a according to the second embodiment. In the following, among the configuration of the fuel cell module 10a according to the second embodiment, the same configuration as that of the fuel cell module 10 according to the first embodiment described above will be denoted by the same reference numerals and the description thereof will be omitted as appropriate.

[0073] In the fuel cell module 10a of the second embodiment, the first insulating material 510a and the configuration around the first insulating material 510a are different from those of the fuel cell module 10 of the first embodiment. Specifically, the hole 512a formed in the first insulating material 510a penetrates in the vertical direction. Therefore, the hole 512a does not have a portion corresponding to the bottom surface S4 of the hole 512 of the first embodiment. The fuel cell module 10a also includes a second insulating material 520. The second insulating material 520 is disposed inside the hole 512a above the support member 540. The second insulating material 520 is a separate insulating material from the first insulating material 510a. The second insulating material 520 has a relatively low thermal conductivity, at least lower than that of the support member 540. The second insulating material 520 is denser than the first insulating material 510. In other words, second heat insulating material 520 is less likely to deform than first heat insulating material 510. There are no particular limitations on the specific material that constitutes second heat insulating material 520, but examples include alumina and ceramic fiber.

[0074] As described above, in the fuel cell module 10a of the second embodiment, the second heat insulating material 520 disposed inside the hole 512a is located above the support member 540. According to the fuel cell module 10a of the second embodiment, since the second heat insulating material 520 is located above the support member 540, heat transfer via the support member 540 can be suppressed, and a decrease in the temperature of the fuel cell stack 100 can be suppressed.

[0075] Furthermore, in the fuel cell module 10a of the second embodiment, a second insulating material 520 is located above the support member 540, and the second insulating material 520 is denser than the first insulating material 510. According to the fuel cell module 10a of the second embodiment, the second insulating material 520 is denser than the first insulating material 510 and is therefore less likely to deform than the first insulating material 510, and therefore can effectively support the load of the fuel cell stack 100.

[0076] C. Third embodiment: 11 is an explanatory diagram showing an enlarged cross section of a fuel cell module 10b according to the third embodiment. In the following, among the configuration of the fuel cell module 10b according to the third embodiment, the same configuration as that of the fuel cell module 10 according to the first embodiment described above will be denoted by the same reference numerals and the description thereof will be omitted as appropriate.

[0077] In the fuel cell module 10b of the third embodiment, the first insulating material 510b and the configuration around the first insulating material 510b are different from those of the fuel cell module 10 of the first embodiment. Specifically, as shown in FIG. 11 , the first insulating material 510b is disposed adjacent to and below the housing 410, which is the supported object, and bears the weight of the housing 410. In other words, the first insulating material 510b is disposed between the fuel cell stack 100 and the housing 410, which are arranged vertically side by side. A hole 512b formed in the first insulating material 510b penetrates the fuel cell stack 100 in the vertical direction. Therefore, the hole 512b does not have a portion corresponding to the bottom surface S4 of the hole 512 of the first embodiment. The fuel cell module 10b also includes a second insulating material 520b. In the fuel cell module 10b, two second insulating materials 520b are disposed for each hole 512b. Above and below the support member 540 is a second insulating material 520b disposed within the hole 512b.

[0078] As described above, in the fuel cell module 10b of the third embodiment, the first heat insulating material 510b is disposed adjacent to and below the housing 410 as the supported body, and at least one hole 512b is formed in the first heat insulating material 510b. The second heat insulating materials 520b disposed inside the hole 512b are located above and below the support member 540. According to the fuel cell module 10b of the third embodiment, since the second heat insulating materials 520b are located above and below the support member 540, heat transfer via the support member 540 can be suppressed, and a decrease in the temperature of the housing 410 can be suppressed.

[0079] Furthermore, in the fuel cell module 10b of the third embodiment, the first heat insulating material 510b is disposed between the fuel cell stack 100 and the housing 410, which are arranged side by side in the vertical direction, the holes 512b penetrate in the vertical direction, and the second heat insulating material 520b is located above and below the support member 540. According to the fuel cell module 10b of the third embodiment, since the second heat insulating material 520b is located above and below the support member 540, the transfer of heat between the fuel cell stack 100 and the housing 410 via the support member 540 can be suppressed.

[0080] D. Variations: The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified into various forms without departing from the spirit thereof, for example, the following modifications are also possible.

[0081] The configurations of the fuel cell module 10 and the fuel cell stack 100 in the above-described embodiments are merely examples and can be modified in various ways. For example, the number of unit cells 110 (the number of reaction units 101U) included in the fuel cell stack 100 in the above-described embodiments is merely an example, and the number of unit cells 110 is determined appropriately depending on the output voltage required for the fuel cell stack 100.

[0082] In the above embodiment, the container (housing 410) allows the gas supplied to the fuel cell stack 100 and the gas discharged from the fuel cell stack 100 to flow through, but it is sufficient if the container allows at least one of the gas supplied to the fuel cell stack and the gas discharged from the fuel cell stack to flow through.

[0083] In the first embodiment, the first insulating material 510 is located above the support member 540, but the first insulating material may be located below the support member, or the first insulating material may be located above and below the support member. Similarly, in the second embodiment, the second insulating material 520 is located above the support member 540, but the second insulating material may be located below the support member.

[0084] In the second embodiment, the second insulating material 520 is denser than the first insulating material 510, but this is not necessarily limited to this, and the first insulating material may be denser than the second insulating material.

[0085] In the above embodiment, the area of ​​the supporting surface S1 is 5% or more and 50% or less of the area of ​​the supported surface S2, but this is not necessarily limited to this.

[0086] The material of the support member 540 in the above embodiment is merely an example. The surface of the support member 540 may be coated with a conductive or insulating material.

[0087] In the above embodiment, a solid oxide fuel cell (SOFC) has been described as an example, but the technology disclosed in this specification can also be applied to other types of fuel cells (or electrolytic cells), such as a polymer electrolyte fuel cell (PEFC), a phosphoric acid fuel cell (PAFC), and a molten carbonate fuel cell (MCFC). [Explanation of symbols]

[0088] 10, 10a, 10b: fuel cell module 100: fuel cell stack 101: power generation block 101U: reaction unit 110: single cell 112: electrolyte layer 114: air electrode 116: fuel electrode 118: reaction prevention layer 120: single cell separator 130: air electrode frame 140: fuel electrode frame 144: fuel electrode current collecting member 149: spacer 180: IC separator 190: interconnector 196: conductive bonding material 210: first end plate 220: insulating part 230: terminal separator 232: first plate 240: first terminal plate 250: second terminal plate 260: second plate 270: second end plate 280: gas passage member 311: oxidant gas supply manifold 312: oxidant gas discharge manifold 313: air chamber 321: Fuel gas supply manifold 322: Fuel gas discharge manifold 323: Fuel chamber 400: Auxiliary device 410: Housing 420: Combustor 430: Reformer 440: Evaporator 510, 510a, 510b: First heat insulating material 512, 512a, 512b: Holes 520, 520b: Second heat insulating material 540: Support member S1: Support surface S2: Supported surface S3: Side surface S4: Bottom surface FG: Fuel gas FOG: Fuel off-gas OG: Oxidant gas OOG: Oxidant off-gas

Claims

1. an electrochemical reaction cell stack; a container through which at least one of a gas supplied to the electrochemical reaction cell stack and a gas discharged from the electrochemical reaction cell stack flows; a first insulating material that can be deformed by an external force, the first insulating material being disposed adjacent to a supported object that is one of the electrochemical reaction cell stack and the container, and having at least one hole formed therein; a support member capable of supporting the supported object and disposed inside the hole; An electrochemical reaction module comprising: At least one of the first insulating material and a second insulating material disposed inside the hole is located above and below the support member. An electrochemical reaction module comprising:

2. 10. The electrochemical reaction module according to claim 1, the first thermal insulator is disposed between the electrochemical reaction cell stack and the container, which are arranged side by side in the vertical direction; The hole penetrates in the vertical direction, The electrochemical reaction module, wherein the second insulating material is located above and below the support member.

3. 10. The electrochemical reaction module according to claim 1, An electrochemical reaction module, wherein the area of ​​the support surface, which is the surface of the support member facing the supported surface, is 5% or more and 50% or less of the area of ​​the supported surface, which is the surface of the supported member facing the support member.

4. 10. The electrochemical reaction module according to claim 1, The electrochemical reaction module, wherein the support member is an insulator.

5. 10. The electrochemical reaction module according to claim 1, The electrochemical reaction module, wherein the support member is made of metal.

6. 10. The electrochemical reaction module according to claim 1, the second insulating material is located above and / or below the support member; The electrochemical reaction module, wherein the second insulating material is denser than the first insulating material.

Images