Solid oxide fuel cell and method for manufacturing the same

Abstract

To provide a technique of preventing leakage of gas by separation input.SOLUTION: A solid oxide fuel cell 1 has: a frame material 2; a metal supporting body 3; a dense joint part 7 for joining the frame material 2 and the metal supporting body 3 to each other; and a fuel battery cell 13. The dense joint part 7 has: an inner periphery end surface joint part as a part joined to an inner periphery end surface of the frame material; and a supporting body joint part as a part joined to the metal supporting body and continuous to the inner periphery end surface joint part. The metal supporting body has a filling part 10 overlapping with the dense joint part at least partially.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a solid oxide fuel cell and a method for manufacturing the same.

Background Art

[0002] A solid oxide fuel cell is a fuel cell that uses a solid material as an electrolyte. A solid oxide fuel cell usually has an electrolyte layer, a fuel electrode layer, and an air electrode layer as a fuel cell cell. During power generation, a fuel gas is supplied to the fuel electrode layer and an oxidant gas is supplied to the air electrode layer, respectively.

[0003] As a solid oxide fuel cell, a metal-supported type is known. A metal-supported solid oxide fuel cell is a battery having a configuration in which a fuel cell cell is supported by a metal support (metal support). That is, the fuel cell cell is disposed on the metal support. As the metal support, a porous material is usually used. By using a porous material, gas can permeate through the metal support. Thereby, gas can be supplied to the fuel cell cell through the metal support.

[0004] In a metal-supported solid oxide fuel cell, the metal support may be further supported by a frame material. In such a battery, it is desired that the frame material and the metal support are firmly joined. Further, when the metal support has a porous structure, there is a possibility that gas leaks from the end of the metal support. Gas leakage reduces the power generation efficiency. Therefore, a configuration for preventing gas leakage from the end of the metal support is also required.

[0005] In relation to the above, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2016-207630) discloses a "metal-supported solid oxide fuel cell comprising an anode layer, a cathode layer, an electrolyte layer provided between the anode layer and the cathode layer, and a support layer provided on one main surface of the anode layer and having communication holes that enable the inflow of fuel gas into the anode layer, and a metal frame provided around the fuel cell cell, wherein the support layer contains a metal, and the fuel cell cell and the metal frame are joined via a seal member containing a metal."

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The inventors of the present invention have been studying a metal-supported solid oxide fuel cell having a configuration in which a metal support is disposed on a frame material. In such a solid oxide fuel cell, a load may be applied such that the frame material and the metal support separate. Hereinafter, such an applied load is referred to as "peeling input". Due to the peeling input, the interface structure between the frame material and the metal support may be destroyed, and gas may leak through the destroyed interface.

[0008] Therefore, an object of the present invention is to provide a technique capable of preventing gas leakage due to peeling input.

Means for Solving the Problems

[0009] A solid oxide fuel cell according to one aspect of the present invention includes a frame member, a porous metal support disposed on the upper surface of the frame member so as to close the opening of the frame member, a dense joint portion that is made of metal and joins the frame member and the metal support, and a fuel cell stack provided on the metal support, the fuel cell stack including a fuel electrode layer, an electrolyte layer, and an air electrode layer. The dense joint portion has an inner peripheral end face joint portion that is a portion joined to the inner peripheral end face of the frame member, and a support joint portion that is a portion joined to the metal support and is continuous with the inner peripheral end face joint portion. The metal support is provided at a position where at least a part thereof overlaps the dense joint portion when viewed along the stacking direction, and has a filling portion that extends from the support joint portion toward the fuel cell stack side. The filling portion is filled with a filler so as to block the movement of gas in the plane direction.

Advantages of the Invention

[0010] According to the present invention, a technique for preventing gas leakage due to peeling input is provided.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0013] FIG. 1 is a schematic cross-sectional view showing a solid oxide fuel cell 1 according to the present embodiment. FIG. 2 is a plan view of the solid oxide fuel cell 1, which is a view when the solid oxide fuel cell is viewed from one side (the air electrode layer side described later). FIG. 3 is also a plan view of the solid oxide fuel cell 1. However, FIG. 3 is a view when the solid oxide fuel cell 1 is viewed from the other side (the metal support side described later).

[0014] As shown in FIGS. 1 to 3, the solid oxide fuel cell 1 includes a frame member 2, a metal support 3, a fuel cell 13, and a dense joint 7.

[0015] The frame member 2 is provided to support the metal support 3 and the fuel cell 13. The frame member 2 has a frame shape with an opening. The frame member 2 has an upper surface, an inner peripheral end surface, and a lower surface.

[0016] The metal support 3 is provided to support the fuel cell 13. By using the metal support 3, the shape of the fuel cell 13 can be maintained even when the fuel cell 13 is thin.

[0017] The metal support 3 itself is supported by the frame member 2. Specifically, the metal support 3 has an upper surface and a lower surface. The metal support 3 is placed on the inner peripheral portion of the upper surface of the frame member 2 at the outer peripheral portion of its lower surface. That is, the metal support 3 is disposed on the upper surface of the frame member 2 so as to close the opening of the frame member 2. Note that, as described above, the fuel cell 13 is disposed on the upper surface of the metal support 3.

[0018] The metal support 3 is porous. As a result, gas can pass through the metal support 3 in the thickness direction. That is, gas can be supplied from the outside to the fuel cell 13 through the openings of the frame material 2 and the metal support 3.

[0019] The dense joint portion 7 is a portion that joins the frame material 2 and the metal support 3. The dense joint portion 7 is made of metal and has a dense structure. Note that, for the dense joint portion 7, being "made of metal" means that the dense joint portion 7 is formed almost entirely of metal. The metal content in the dense joint portion 7 is, for example, 90 mass% or more, preferably 95 mass% or more, and more preferably 99 mass% or more.

[0020] The dense joint portion 7 has an inner peripheral end face joint portion 7-1, a support joint portion 7-2, and a lower surface covering portion 7-3. These are continuous.

[0021] The inner peripheral end face joint portion 7-1 is a portion joined to the inner peripheral end face of the frame material 2.

[0022] The support joint portion 7-2 is a portion joined to the metal support 3. In the present embodiment, the support joint portion 7-2 extends so as to enter from the lower surface of the metal support 3 into the metal support 3.

[0023] The lower surface covering portion 7-3 is a portion that covers a part (inner peripheral portion) of the lower surface of the frame material 2.

[0024] The fuel cell 13 is a portion that realizes the power generation function. As described above, the fuel cell 13 is disposed on the metal support 3. The fuel cell 13 has a fuel electrode layer 4, an electrolyte layer 5, and an air electrode layer 6. These are laminated such that the electrolyte layer 5 is sandwiched between the fuel electrode layer 4 and the air electrode layer 6 in the lamination direction.

[0025] Here, in the present embodiment, a filling portion 10 is provided on the metal support 3 in order to prevent gas leakage. The filling portion 10 is provided at a position that at least partially overlaps the dense joint portion 7 when viewed along the stacking direction. The filling portion 10 extends from the support joint portion 7-2 toward the fuel cell 13 side along the stacking direction. In the present embodiment, the filling portion 10 extends from the support joint portion 7-2 to reach the fuel cell 13 (fuel electrode layer 4). When viewed along the stacking direction, the filling portion 10 is frame-shaped (see FIG. 3). The filling portion 10 is filled with a filler so that gas movement in the plane direction is blocked. If the filling portion 10 is not provided, the gas to be supplied to the fuel cell 13 may leak from the end of the metal support 3. As a result, the power generation efficiency may decrease. On the other hand, by providing the filling portion 10, gas leakage through the end of the metal support 3 is prevented.

[0026] The above is a schematic configuration of the solid oxide fuel cell 1 according to the present embodiment. According to the present embodiment, since the dense joint portion 7 and the filling portion 10 are provided, gas leakage is prevented even when a peeling input occurs. This point will be described below with reference to reference examples.

[0027] FIG. 4 is a schematic cross-sectional view showing a solid oxide fuel cell 1 according to a reference example. As shown in FIG. 4(a), in this reference example, a glass material 12 is provided on a frame material 2 so as to cover an end face of a metal support 3. This glass material 12 also penetrates into the interface between the frame material 2 and the metal support 3. That is, the upper inner peripheral part of the frame material 2 and the lower outer peripheral part of the metal support 3 are joined via the glass material 12. The glass material 12 prevents leakage of gas. However, when such a configuration is adopted, a peeling force may occur. For example, as shown in FIG. 4(b), a load may be applied to the outer end of the frame material 2 in a direction such that the frame material 2 peels off from the metal support 3. Such a peeling force may destroy the interface structure between the frame material 2 and the metal support 3. As a result, gas may leak through the interface between the frame material 2 and the metal support 3.

[0028] On the other hand, FIG. 5 is a schematic cross-sectional view showing the solid oxide fuel cell 1 according to this embodiment, and shows the configuration when a peeling force is applied. In this embodiment, the inner peripheral end surface of the frame material 2 and the metal support 3 are joined by a dense joint 7 made of metal. Compared to the case where a glass material 12 is used as in the reference example, the use of the dense joint 7 made of metal increases the joining strength between the frame material 2 and the metal support 3. Therefore, even if a peeling force is applied, the joining structure is unlikely to be destroyed at the inner peripheral end surface of the frame material 2. And, since the filling portion 10 is provided on the dense joint 7, gas leakage is prevented on the dense joint 7. That is, according to this embodiment, gas leakage due to a peeling force is more reliably prevented.

[0029] The above is an outline of this embodiment. Next, other preferable configurations will be described.

[0030] In the example shown in FIG. 1, the dense joint portion 7 has a lower surface covering portion 7-3 in addition to the inner peripheral end surface joint portion 7-1 and the support body joint portion 7-2. That is, the dense joint portion 7 has a shape that covers the inner peripheral end surface of the frame member 2 from the outer peripheral portion of the lower surface of the frame member 2 and reaches the metal support body 3. With such a configuration, the strength of the dense joint portion 7 is further increased. Therefore, the joint strength between the metal support body 3 and the frame member 2 can be further enhanced.

[0031] In the example shown in FIG. 1, the support body joint portion 7-2 enters from the lower surface of the metal support body 3 into the inside of the metal support body 3. According to such a configuration, the joint strength between the metal support body 3 and the frame member 2 becomes greater. Therefore, gas leakage due to peeling input can be more reliably prevented.

[0032] However, the support body joint portion 7-2 does not necessarily have to enter into the inside of the metal support body 3. That is, the dense joint portion 7 (support body joint portion 7-2) may be joined to the metal support body 3 on the surface of the lower surface of the metal support body 3. Even in the case of adopting such a configuration, a certain effect can be achieved with respect to preventing gas leakage.

[0033] In a preferred embodiment, the support body joint portion 7-2 enters into the inside of the metal support body 3 at a depth of 0% or more and 90% or less of the thickness of the metal support body 3. When the support body joint portion 7-2 enters into the inside of the metal support body 3 exceeding 90% of the thickness of the metal support body 3, a portion where the stress changes abruptly is likely to occur in the solid oxide fuel cell 1. If the depth of the support body joint portion 7-2 is 90% or less of the thickness of the metal support body 3, it is possible to make it difficult to generate a portion where the stress changes abruptly. The depth of the support body joint portion 7-2 is more preferably 10 to 70% of the thickness of the metal support body 3.

[0034] The dense joint portion 7 can be formed, for example, by laser metal deposition. By using laser metal deposition, the dense joint portion 7 can be formed more easily on the inner peripheral end face of the frame member 2 than in the case of using other joining methods. Further, since laser metal deposition is additive manufacturing, the robustness against other component dimensions can also be enhanced.

[0035] Preferably, the dense joint portion 7, the metal support 3, and the frame member 2 are formed of the same material. If these are formed of the same material, the joining strength between the metal support 3 and the frame member 2 is further improved. As a result, deformation of the fuel cell 13 is suppressed, and cracking of the electrolyte layer 5 and the like is prevented. In the present specification, "formed of the same material" means formed of substantially the same structure. For example, when the dense joint portion 7 is formed of a ferritic stainless steel material, even if the compositions are not completely identical, if the metal support 3 and the frame member 2 are also formed of a ferritic stainless steel material, these can be said to be "formed of the same material". Most preferably, the dense joint portion 7, the metal support 3, and the frame member 2 have the same composition.

[0036] The materials of the dense joint portion 7, the metal support 3, and the frame member 2 are not particularly limited. For example, materials containing Fe, Cr, and the like can be used. Preferably, ferritic stainless steel is used.

[0037] In the example shown in FIG. 1, as a preferred example, an example is shown in which the fuel cell 13 is arranged on the metal support 3 such that the fuel electrode layer 4, the electrolyte layer 5, and the air electrode layer 6 are in this order from the side of the metal support 3. That is, the fuel gas is configured to be supplied to the fuel electrode layer 4 via the metal support 3. Further, when viewed along the stacking direction, the outer peripheral end of the air electrode layer 6 is located inside the outer peripheral ends of the electrolyte layer 5, the fuel electrode layer 4, and the metal support 3. Further, when viewed along the stacking direction, the dense joint portion 7 is arranged outside the air electrode layer 6. In other words, the inner peripheral end of the dense joint portion 7 is located outside the outer peripheral end of the air electrode layer 6. The filling portion 10 is also arranged outside the air electrode layer 6 when viewed along the stacking direction. According to such a configuration, the presence of the filling portion 10 and the dense joint portion 7 does not narrow the active area (the area where power generation is performed). It is possible to prevent a decrease in power generation efficiency, which is preferable.

[0038] However, in the present embodiment, the fuel cell 13 does not necessarily need to be arranged on the metal support 3 such that the fuel electrode layer 4 side faces the metal support 3 side. The fuel cell 13 may be arranged on the metal support 3 such that the air electrode layer side faces the metal support 3 side.

[0039] The filling material filled in the filling portion 10 is not particularly limited. Preferably, as the filling material, an oxide material containing at least one selected from the group consisting of silica, alumina, zirconia, and ceria is used. These materials are preferable from the viewpoints of avoiding short circuits and having high temperature resistance.

[0040] More preferably, the filling material contains glass as a main component (a component occupying 50 mass% or more). If glass is included as the main component, the viscosity of the filling material decreases near the operating temperature, and breakage can be prevented. In addition, self-healing properties can also be imparted to the filling portion 10. The content of glass in the filling material is preferably 90 mass% or more, more preferably 99 mass% or more.

[0041] In a preferred embodiment, the difference in the coefficient of thermal expansion between the filler and the metal support is 0 to 10% with the coefficient of thermal expansion of the metal support being 100%. By adopting such a configuration, damage to the filling portion 10 due to thermal expansion and contraction can be prevented, and gas leakage can be more reliably prevented.

[0042] The filler is, for example, in powder form. In this case, it is preferable that the particle size of the filler is smaller than the pore size of the metal support. The filling portion 10 can be formed, for example, by permeating a dispersion liquid containing the filler and a solvent component into the metal support and removing the solvent component by drying or the like. If the particle size of the filler is smaller than the pore size of the metal support, the filler can easily enter the metal support when the filler is permeated into the metal support. The particle size of the filler can be determined, for example, by acquiring an image of the filler from a micrograph, obtaining the equivalent circle diameter of the filler particles from the image, and calculating the number average. The pore size of the metal support can also be determined by the same image processing.

[0043] In the example shown in FIG. 1, the filler is further filled in a part of the fuel electrode layer 4. Hereinafter, the portion of the fuel electrode layer 4 filled with the filler is defined as the fuel electrode layer filling portion 11. Specifically, the fuel electrode layer 4 is porous. And in the fuel electrode layer filling portion 11, the filler is filled so as to fill the pores. The fuel electrode layer filling portion 11 is provided at a position overlapping the filling portion 10 when viewed along the stacking direction. The fuel electrode layer filling portion 11 is continuous with the filling portion 10 in the metal support 3. That is, the filler is filled in the metal support 3 and the fuel electrode layer 4 to a depth that reaches the lower surface of the electrolyte layer 5 from the dense joint portion 7. According to such a configuration, gas leakage through the fuel electrode layer 4 is also prevented. That is, gas leakage is more reliably prevented.

[0044] The above-mentioned dense joint portion 7 and filling portion 10 can be confirmed, for example, by SEM and EDS analysis. FIG. 6A is an SEM photograph showing an example of a solid oxide fuel cell according to the present embodiment. Further, FIG. 6B is a diagram showing the EDS analysis result (Fe) of the solid oxide fuel cell. Note that, as the metal support, dense joint portion, and frame material, a material containing Fe was used. Also, a glass material was used as the filler. The dense joint portion was formed using laser powder cladding. In FIGS. 6A and 6B, region A is the filler (glass), region B is the region where the filler is filled in the metal support (i.e., the filling portion 10), region C is the dense joint portion, and region D is the metal support. As shown in FIGS. 6A and 6B, the structures of the dense joint portion 7 and the filling portion 10 can be confirmed by using SEM, EDS analysis, etc.

[0045] The constituent material of the fuel cell 13 is not particularly limited.

[0046] For example, the electrolyte layer 5 is formed of a dense ceramic layer. Note that ceramics refer to a sintered body of inorganic substances and is a concept that includes not only non-metal oxides but also metal oxides. The electrolyte layer 5 only needs to be configured to be capable of conducting oxide ions and, on the other hand, not permeable to gas. For example, the electrolyte layer 5 can be formed of solid oxide ceramics. The solid oxide ceramics are not particularly limited, and examples thereof include zirconia-containing materials. Examples of the zirconia-containing materials include stabilized zirconia doped with yttria, neodymium oxide, samarium, gadolinium, scandium, and the like. The thickness of the electrolyte layer 5 is, for example, 0.5 to 20 μm, preferably 1 to 10 μm.

[0047] The fuel electrode layer 4 and the air electrode layer 6 are layers where electron transfer occurs during power generation. The air electrode layer 6 is mainly composed of a perovskite material such as LSC or LSCF, or a porous ceramic layer. The fuel electrode layer 4 is mainly composed of, for example, a cermet layer obtained by mixing nickel and a zirconia-containing material which is an electrolyte material, or a porous ceramic. The thicknesses of the fuel electrode layer 4 and the air electrode layer 6 are, for example, 0.3 to 50 μm, preferably 0.5 to 30 μm, respectively.

[0048] The manufacturing method of the solid oxide fuel cell according to this embodiment is not particularly limited. Hereinafter, an example will be given to explain the manufacturing method of the solid oxide fuel cell.

[0049] First, a green sheet for the metal support 3, a green sheet for the fuel electrode layer 4, a green sheet for the electrolyte layer 5, and a green sheet for the air electrode layer 6 are laminated and fired. Thereby, a laminate having a configuration in which the fuel cell cell 13 is laminated on the metal support 3 is obtained.

[0050] Subsequently, the laminate is placed on the frame material 2. And the dense joint part 7 is formed. That is, the inner peripheral end face of the frame material 2 and the metal support 3 are joined. As described above, the dense joint part 7 can be formed by laser powder cladding.

[0051] Subsequently, a filling material supply region which is to become the filling part 10 is set on the metal support 3. Also, a dispersion liquid containing a powdery filling material and a solvent component is prepared. And the dispersion liquid is made to penetrate | permeate | infiltrate into a filler supply area | region. The dispersion liquid can be made to penetrate | permeate | infiltrate by capillary action etc. As the solvent component, ethanol, butyl acetate, etc. can be used. Next, the solvent component is removed by volatilization or the like. Thereby, the filling part 10 is formed. In addition, if the dispersion liquid is made to penetrate | permeate | infiltrate until it reaches the fuel electrode layer 4, the fuel electrode layer filling part 11 can be formed in the fuel electrode layer 4. Thereby, the solid oxide fuel cell which concerns on this embodiment can be obtained.

[0052] Note that the filling portion 10 does not necessarily have to be formed after the formation of the dense joint portion 7. For example, the dense joint portion 7 may be formed after the filling portion 10 is formed.

[0053] As described above, the present invention has been described using embodiments. Hereinafter, typical configurations in this embodiment and their effects will be summarized.

[0054] In one aspect, the solid oxide fuel cell 1 according to this embodiment includes a frame material 2, a porous metal support 3 disposed on the upper surface of the frame material 2 so as to close the opening of the frame material 2, a dense joint portion 7 made of metal that joins the frame material 2 and the metal support 3, and a fuel cell stack 13 provided on the metal support 3, the fuel cell stack including a fuel electrode layer 4, an electrolyte layer 5, and an air electrode layer 6. The dense joint portion 7 has an inner peripheral end surface joint portion 7-1 that is a portion joined to the inner peripheral end surface of the frame material, and a support joint portion 7-2 that is a portion joined to the metal support 3 and is continuous with the inner peripheral end surface joint portion 7-1. The metal support 3 is provided at a position where at least a part thereof overlaps the dense joint portion 7 when viewed along the stacking direction, and has a filling portion 10 that extends from the support joint portion toward the fuel cell stack side. The filling portion 10 is filled with a filling material so as to block the movement of gas in the plane direction.

[0055] According to the configuration as described above, since the frame material 2 and the metal support 3 are joined by the metal dense joint portion 7, high joining strength can be obtained. Further, since the filling portion 10 is provided inside the metal support 3 and this filling portion 10 is provided at a position overlapping the dense joint portion 7, even when a peeling input is applied, the filling portion 10 is protected by the dense joint portion 7. Therefore, the reliability regarding gas sealing is improved.

[0056] In a preferred aspect, the support joint portion 7-2 extends from the lower surface of the metal support 3 into the inside of the metal support. According to such a configuration, the strength of the dense joint portion 7 is further improved, and the reliability regarding gas sealing is further improved.

[0057] In a preferred embodiment, the support joint portion 7-2 penetrates into the interior of the metal support 3 from the lower surface of the metal support 3 at a depth of 0% or more and 90% or less of the thickness of the metal support 3. According to such a configuration, it is possible to prevent the occurrence of a stress concentration portion.

[0058] In a preferred embodiment, the dense joint portion 7, the metal support 3, and the frame material 2 are formed of the same material. According to such a configuration, the bonding strength between the metal support 3 and the frame material 2 is further improved.

[0059] In a preferred embodiment, the fuel cell 13 is disposed on the metal support 3 in the order of the fuel electrode layer 4, the electrolyte layer 5, and the air electrode layer 6 from the metal support 3 side. When viewed along the stacking direction, the dense joint portion 7 is disposed outside the air electrode layer 6. According to such a configuration, a wide active area can be secured.

[0060] In a preferred embodiment, the dense joint portion 7 further has a lower surface covering portion 7-3 that is continuous with the inner peripheral end surface joint portion 7-1 and covers a part of the lower surface of the frame material 2. According to such a configuration, the strength of the dense joint portion 7 can be further improved, and the reliability regarding gas sealing can be further enhanced.

[0061] In a preferred embodiment, the fuel cell 13 is disposed on the metal support 3 in the order of the fuel electrode layer 4, the electrolyte layer 5, and the air electrode layer 6 from the metal support 3 side. When viewed along the stacking direction, the filling portion 10 is disposed outside the air electrode layer 6. According to such a configuration, a wide active area can be secured.

[0062] In a preferred embodiment, the difference in the coefficient of thermal expansion between the filler and the metal support 3 is 0 to 10% with the coefficient of thermal expansion of the metal support 3 being 100%. According to such a configuration, damage to the filling portion 10 due to thermal expansion and contraction can be prevented, and gas leakage can be more reliably prevented.

[0063] In a preferred embodiment, the filler contains at least one selected from the group consisting of silica, alumina, zirconia, and ceria. By using these materials, short circuits can be avoided, and high-temperature resistance can be obtained.

[0064] In a preferred embodiment, the filler is in powder form, and the particle size of the filler is smaller than the pore diameter of the metal support. By adopting such a configuration, the filler can be easily filled into the metal support during manufacturing.

[0065] In a preferred embodiment, the filler contains glass as a main component. By adopting such a configuration, the viscosity of the filler decreases near the operating temperature, preventing damage. Also, self-healing properties can be imparted to the filled portion.

[0066] In a preferred embodiment, the fuel cell 13 is arranged on the metal support 3 in the order of the fuel electrode layer 4, the electrolyte layer 5, and the air electrode layer 6 from the side of the metal support 3. The fuel electrode layer 4 is porous. The fuel electrode layer 4 has a fuel electrode filled portion 11 which is a portion filled with the filler. The fuel electrode filled portion 11 is provided at a position overlapping the filled portion 10 when viewed along the stacking direction. According to such a configuration, gas leakage through the end of the fuel electrode layer 4 is also prevented.

[0067] In a preferred embodiment, the method for manufacturing a solid oxide fuel cell includes a step of forming a dense joint by laser powder cladding. According to such a method, the dense joint 7 can be easily formed on the inner peripheral end face of the frame member 2. Also, since laser powder cladding is additive manufacturing, the robustness against other component dimensions can be enhanced.

[0068] In a preferred embodiment, a method for manufacturing a solid oxide fuel cell includes a step of infiltrating a dispersion liquid containing a powdery filler and a solvent component into a filler supply region that is to become a filling portion, and a step of forming the filling portion by removing the solvent component after the infiltrating step. By using such a method, the filling portion 10 can be formed on the metal support 3.

Explanation of reference numerals

[0069] 1 ··· Solid oxide fuel cell, 2 ··· Frame material, 3 ··· Metal support, 4 ··· Fuel electrode layer, 5 ··· Electrolyte layer, 6 ··· Air electrode layer, 7 ··· Dense joint portion, 10 ··· Filling portion, 11 ··· Fuel electrode layer filling portion, 12 ··· Glass material, 13 ··· Fuel cell

Claims

1. A frame material, A porous metal support disposed on the upper surface of the frame material so as to close the opening of the frame material, A dense joint portion made of metal for joining the frame material and the metal support, A fuel cell provided on the metal support, the fuel cell including a fuel electrode layer, an electrolyte layer, and an air electrode layer, comprising: The dense joint portion An inner peripheral end face joint portion which is a portion joined to the inner peripheral end face of the frame material, A support body joint portion which is a portion joined to the metal support and is continuous with the inner peripheral end face joint portion, The metal support is provided at a position where at least a part thereof overlaps the dense joint portion when viewed along the stacking direction, and has a filling portion extending from the support body joint portion toward the fuel cell side, The filling portion is filled with a filler so as to block the movement of gas in the plane direction. A solid oxide fuel cell.

2. The solid oxide fuel cell according to claim 1, The support body joint portion extends from the lower surface of the metal support into the metal support. A solid oxide fuel cell.

3. The solid oxide fuel cell according to claim 1 or 2, The support body joint portion enters the metal support from the lower surface of the metal support at a depth of 0% or more and 90% or less of the thickness of the metal support. A solid oxide fuel cell.

4. The solid oxide fuel cell according to claim 1 or 2, The dense joint portion, the metal support, and the frame material are formed of the same material. A solid oxide fuel cell.

5. The solid oxide fuel cell according to claim 1 or 2, wherein the fuel cell is arranged on the metal support in the order of the fuel electrode layer, the electrolyte layer, and the air electrode layer from the metal support side, when viewed along the stacking direction, the dense joint portion is arranged outside the air electrode layer, Solid oxide fuel cell.

6. The solid oxide fuel cell according to claim 1 or 2, the dense joint portion further has a lower surface covering portion that is continuous with the inner peripheral end surface joint portion and covers a part of the lower surface of the frame material, Solid oxide fuel cell.

7. The solid oxide fuel cell according to claim 1 or 2, wherein the fuel cell is arranged on the metal support in the order of the fuel electrode layer, the electrolyte layer, and the air electrode layer from the metal support side, when viewed along the stacking direction, the filling portion is arranged outside the air electrode layer, Solid oxide fuel cell.

8. The solid oxide fuel cell according to claim 1 or 2, the difference in the coefficient of thermal expansion between the filler and the metal support is 0 to 10% with the coefficient of thermal expansion of the metal support being 100%, Solid oxide fuel cell.

9. The solid oxide fuel cell according to claim 1 or 2, the filler contains at least one selected from the group consisting of silica, alumina, zirconia, and ceria, Solid oxide fuel cell.

10. The solid oxide fuel cell according to claim 1 or 2, the filler is in powder form, The particle size of the filler is smaller than the pore diameter of the metal support. Solid oxide fuel cell.

11. The solid oxide fuel cell according to claim 1 or 2, wherein the filler contains glass as a main component. Solid oxide fuel cell.

12. The solid oxide fuel cell according to claim 1 or 2, wherein the fuel cell cell is disposed on the metal support so as to be in the order of the fuel electrode layer, the electrolyte layer, and the air electrode layer from the metal support side, the fuel electrode layer is porous, the fuel electrode layer has a fuel electrode layer filling portion which is a portion filled with the filler, the fuel electrode layer filling portion is provided at a position overlapping the filling portion when viewed along the stacking direction. Solid oxide fuel cell.

13. A method for manufacturing a solid oxide fuel cell according to claim 1 or 2, comprising a step of forming the dense joint portion by laser powder build-up. Method for manufacturing a solid oxide fuel cell.

14. A method for manufacturing a solid oxide fuel cell according to claim 1 or 2, a step of infiltrating a dispersion liquid containing a powdery filler and a solvent component into a region to be the filling portion; and a step of forming the filling portion by removing the solvent component after the infiltrating step. comprising Method for manufacturing a solid oxide fuel cell.

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