Cell, cell stack device, module, and module housing device

Abstract

To provide a cell, a cell stack device, a module, and a module housing device that can improve battery performance.SOLUTION: A cell includes an element part. The element part has a first electrode and a second electrode. The element part has a concave outer surface on a surface of the second electrode located on the opposite side of the first electrode.SELECTED DRAWING: Figure 1C

Description

[Technical field]

[0001] The present disclosure relates to a cell, a cell stack device, a module, and a module housing device. [Background technology]

[0002] In recent years, various cell stack devices having multiple fuel cells have been proposed as next-generation energy sources. A fuel cell is a type of cell that can generate electric power using a fuel gas such as a hydrogen-containing gas and an oxygen-containing gas such as air. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-168227 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned cell stack device has room for improvement in terms of improving battery performance.

[0005] One aspect of the embodiment has been made in view of the above, and aims to provide a cell, a cell stack device, a module, and a module housing device that can improve battery performance. [Means for solving the problem]

[0006] A cell according to one aspect of the embodiment includes an element portion having a first electrode and a second electrode, the element portion having a concave outer surface on a surface of the second electrode located opposite to the first electrode.

[0007] Moreover, the cell stack device of the present disclosure has a cell stack in which a plurality of cells are arranged, and at least one of the plurality of cells is the cell described above.

[0008] Moreover, the module of the present disclosure includes the cell stack device described above and a storage container that stores the cell stack device.

[0009] The module housing device of the present disclosure includes the above-described module, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device. Effect of the Invention

[0010] According to one aspect of the embodiment, it is possible to provide a cell, a cell stack device, a module, and a module housing device that can improve battery performance. [Brief description of the drawings]

[0011] [Figure 1A] FIG. 1A is a cross-sectional view showing an example of a cell according to a first embodiment. [Figure 1B] FIG. 1B is a plan view of an example of a cell according to the first embodiment, viewed from the air electrode side. [Figure 1C] FIG. 1C is a vertical cross-sectional view illustrating an example of a cell according to the first embodiment. [Figure 2A] FIG. 2A is a perspective view showing an example of a cell stack device according to the first embodiment. [Figure 2B] FIG. 2B is a cross-sectional view taken along line XX shown in FIG. 2A. [Figure 2C] FIG. 2C is a top view showing an example of the cell stack device according to the first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing an example of a cell according to a first modified example of the first embodiment. [Figure 4] FIG. 4 is a vertical cross-sectional view showing an example of a cell according to a second modified example of the first embodiment. [Diagram 5] FIG. 5 is a cross-sectional view showing an example of a cell according to a third modified example of the first embodiment. [Figure 6] FIG. 6 is a vertical cross-sectional view showing an example of a cell according to a fourth modified example of the first embodiment. [Figure 7A]FIG. 7A is a vertical cross-sectional view showing an example of a cell according to a fifth modified example of the first embodiment. [Figure 7B] FIG. 7B is a vertical cross-sectional view showing an example of a cell stack including the cell shown in FIG. 7A. [Figure 8] FIG. 8 is an external perspective view illustrating an example of the module according to the first embodiment. [Figure 9] FIG. 9 is an exploded perspective view illustrating an example of a module housing device according to the first embodiment. [Figure 10A] FIG. 10A is a cross-sectional view showing an example of a cell according to the second embodiment. [Figure 10B] FIG. 10B is a cross-sectional view showing an example of a cell stack including the cell shown in FIG. 10A. [Figure 11] FIG. 11 is a cross-sectional view showing an example of a cell according to a modified example of the second embodiment. [Figure 12A] FIG. 12A is a perspective view showing an example of a flat cell according to the third embodiment. [Figure 12B] FIG. 12B is a cross-sectional view taken along line YY shown in FIG. 12A. [Figure 12C] FIG. 12C is a cross-sectional view taken along line ZZ shown in FIG. 12B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of a cell, a cell stack device, a module, and a module housing device disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the disclosure is not limited to the embodiments described below.

[0013] In addition, it should be noted that the drawings are schematic, and that the dimensional relationships, ratios, etc. of each element may differ from the reality. Furthermore, there may be cases where the dimensional relationships, ratios, etc. of each element differ from those of the drawings.

[0014] [First embodiment] <Cell configuration> First, with reference to FIGS. 1A to 1C, a cell according to a first embodiment will be described using an example of a solid oxide fuel cell.

[0015] Fig. 1A is a transverse cross-sectional view showing an example of a cell 1 according to the first embodiment, Fig. 1B is a plan view of the example of the cell 1 according to the first embodiment seen from the air electrode 8 side, and Fig. 1C is a longitudinal cross-sectional view showing an example of the cell according to the first embodiment. Note that Figs. 1A to 1C show enlarged views of parts of each component of the cell 1.

[0016] 1A to 1C, cell 1 is a hollow flat plate-like elongated plate. As shown in Fig. 1B, the shape of cell 1 as a whole viewed from the side is, for example, a rectangle with a side length of 5 cm to 50 cm in the length direction L and a length of 1 cm to 10 cm in the width direction W perpendicular to the length direction L. The thickness of cell 1 as a whole in the thickness direction T is 1 mm to 5 mm.

[0017] 1A, the cell 1 includes a conductive supporting substrate 2, an element portion 3, and an interconnector 4. The supporting substrate 2 is columnar having a pair of opposing surfaces n1, n2, and a pair of arc-shaped side surfaces m connecting the surfaces n1, n2.

[0018] The element unit 3 is provided on a surface n1 of the support substrate 2. The element unit 3 has an anode 5, a solid electrolyte layer 6, and an air electrode 8. The air electrode 8 has an outer surface 3a of the element unit 3 exposed to the outside. The anode 5 is an example of a first electrode, and the air electrode 8 is an example of a second electrode. In the example shown in FIG. 1A, an interconnector 4 is provided on the other surface n2 of the cell 1. The cell 1 may have an intermediate layer 7 between the solid electrolyte layer 6 and the air electrode 8.

[0019] 1B, the air electrode 8 does not extend to the upper and lower ends of the cell 1. At the lower end of the cell 1, only the solid electrolyte layer 6 is exposed on the surface. The detailed shape of the element unit 3 including the air electrode 8 will be described later.

[0020] On the other hand, the interconnector 4 may extend to the lower end of the cell 1. At the lower end of the cell 1, the interconnector 4 and the solid electrolyte layer 6 are exposed on the surface. As shown in FIG. 1A, the solid electrolyte layer 6 is exposed on the surface of a pair of arc-shaped side surfaces m of the cell 1. The interconnector 4 does not have to extend to the lower end of the cell 1.

[0021] Each of the components constituting the cell 1 will be described below.

[0022] The support substrate 2 has therein gas flow channels 2a through which gas flows. The example of the support substrate 2 shown in FIG. 1A has six gas flow channels 2a. The support substrate 2 has gas permeability and allows the fuel gas flowing through the gas flow channels 2a to permeate to the anode 5. The support substrate 2 may be conductive. The conductive support substrate 2 collects electricity generated in the power generation element to the interconnector 4.

[0023] As shown in FIG. 1C , the element portion 3 has a concave outer surface 3a located on the outermost air electrode 8. The outer surface 3a has portions 31 to 33. The portion 31 is located in the center in the longitudinal direction L. The portion 32 is located on the upper end side of the outer periphery of the air electrode 8 in the longitudinal direction L in a plan view of the air electrode 8, and the portion 33 is located on the lower end side of the outer periphery of the air electrode 8 in the longitudinal direction L in a plan view of the air electrode 8. The portions 31 to 33 have predetermined thicknesses t1 to t3 in the thickness direction T, respectively. The portions 31 to 33 are examples of first to third portions.

[0024] In the example shown in Fig. 1C, a fuel gas, which is a reactant gas, flows through a gas flow passage 2a (see Fig. 1A) located along the length direction L from the lower end side to the upper end side of the cell 1. An oxygen-containing gas, which is also a reactant gas, flows outside the cell 1 along the length direction L from the lower end side to the upper end side of the cell 1. That is, the portion 32 is located downstream of the flow of the oxygen-containing gas, and the portion 33 is located upstream of the flow of the oxygen-containing gas.

[0025] A thickness t2 of the element portion 3 in a portion 32 located downstream of the portion 31 in the oxygen-containing gas flow is greater than a thickness t1 of the element portion 3 in the portion 31. This makes it easier for the oxygen-containing gas flowing around the element portion 3 from the lower end side to the upper end side of the cell 1 to be taken into the air electrode 8. This improves the reactivity at the upper end side of the element portion 3, and improves the battery performance of the cell 1.

[0026] Furthermore, a thickness t3 of the element portion 3 at a portion 33 located upstream of the portion 31 in the oxygen-containing gas flow is greater than a thickness t1 of the element portion 3 at the portion 31. This increases the contact area between the outer surface 3a of the element portion 3 and the oxygen-containing gas, making it easier to take in the oxygen-containing gas into the air electrode 8. This improves the reactivity at the lower end side of the element portion 3, and improves the battery performance of the cell 1.

[0027] In the element unit 3 shown in FIG. 1C, the outer surface 3a is made concave by varying the thickness of the air electrode 8. However, the thickness of one or more of the elements other than the air electrode 8, i.e., the fuel electrode 5, the solid electrolyte layer 6, and the intermediate layer 7, may also be varied.

[0028] The material of the support substrate 2 includes, for example, an iron group metal component and an inorganic oxide. For example, the iron group metal component may be Ni (nickel) and / or NiO. The inorganic oxide may be, for example, a specific rare earth element oxide.

[0029] The material of the fuel electrode 5 may be a generally known material. The fuel electrode 5 may be made of porous conductive ceramics, such as ceramics containing calcium oxide, magnesium oxide, or ZrO2 in which a rare earth element oxide is dissolved, and Ni and / or NiO. As the rare earth element oxide, for example, Y2O3 or the like is used. Calcium oxide, magnesium oxide, or ZrO2 in which a rare earth element oxide is dissolved may be called stabilized zirconia. Stabilized zirconia also includes partially stabilized zirconia.

[0030] The solid electrolyte layer 6 is an electrolyte and acts as a bridge between ions between the fuel electrode 5 and the air electrode 8. At the same time, the solid electrolyte layer 6 has gas barrier properties and makes it difficult for leakage of fuel gas and oxygen-containing gas to occur.

[0031] The material of the solid electrolyte layer 6 may be, for example, ZrO2 in which 3 mol % to 15 mol % of a rare earth element oxide is dissolved. For example, Y2O3 is used as the rare earth element oxide. Note that other materials may be used as the material of the solid electrolyte layer 6 as long as they have the above characteristics.

[0032] There are no particular limitations on the material of the air electrode 8 as long as it is a material generally used for air electrodes. The material of the air electrode 8 may be, for example, a conductive ceramic such as a so-called ABO3 type perovskite oxide.

[0033] The material of the cathode 8 may be, for example, a composite oxide in which Sr and La coexist at the A site. Examples of such composite oxides include La x Sr 1-x Co y Fe 1-y O3, La x Sr 1-x MnO3, La x Sr 1-x FeO3, La x Sr 1-x CoO3, etc. Note that x is 0 <x<1、yは0<y<1である。

[0034] In addition, the air electrode 8 has gas permeability. The open porosity of the air electrode 8 may be, for example, 20% or more, and particularly in the range of 30% to 50%.

[0035] Furthermore, in the case where the element unit 3 has the intermediate layer 7, the intermediate layer 7 may be a diffusion suppression layer. The intermediate layer 7 prevents Sr (strontium) contained in the air electrode 8 from diffusing into the solid electrolyte layer 6, making it difficult for a resistive layer of SrZrO3 to be formed in the solid electrolyte layer 6.

[0036] There is no particular restriction on the material of the intermediate layer 7, so long as it is generally used as a diffusion suppression layer for Sr. The material of the intermediate layer 7 includes, for example, cerium oxide (CeO2) in which rare earth elements other than Ce (cerium) are dissolved. Examples of such rare earth elements include Gd (gadolinium) and Sm (samarium).

[0037] Moreover, the interconnector 4 is dense and prevents leakage of the fuel gas flowing through the gas flow passage 2a located inside the support substrate 2 and the oxygen-containing gas flowing outside the support substrate 2. The interconnector 4 may have a relative density of 93% or more, particularly 95% or more.

[0038] Lanthanum chromite-based perovskite oxides (LaCrO3-based oxides), lanthanum strontium titanium-based perovskite oxides (LaSrTiO3-based oxides), etc. may be used as the material for the interconnector 4. These materials are conductive and are not reduced or oxidized even when in contact with a fuel gas such as a hydrogen-containing gas and an oxygen-containing gas such as air.

[0039] <Configuration of cell stack device> Next, a cell stack device 10 according to this embodiment using the above-mentioned cell 1 will be described with reference to Figures 2A to 2C. Figure 2A is a perspective view showing an example of the cell stack device 10 according to the first embodiment, Figure 2B is a cross-sectional view taken along line AA shown in Figure 2A, and Figure 2C is a top view showing an example of the cell stack device 10 according to the first embodiment.

[0040] As shown in FIG. 2A, the cell stack device 10 includes a cell stack 11 having a plurality of cells 1 arranged (stacked) in a thickness direction T of the cells 1 (see FIG. 1A), and a fixing member 12.

[0041] The fixing member 12 has a bonding material 13 and a support member 14. The support member 14 supports the cell 1. The bonding material 13 bonds the cell 1 and the support member 14. The support member 14 also has a support body 15 and a gas tank 16. The support body 15 and the gas tank 16, which are the support member 14, are made of metal and are conductive.

[0042] 2B, the support 15 has insertion holes 15a into which the lower ends of the multiple cells 1 are inserted. The lower ends of the multiple cells 1 and the inner walls of the insertion holes 15a are joined with a joining material 13.

[0043] The gas tank 16 has an opening for supplying a reaction gas to the cells 1 through the insertion holes 15a, and a groove 16a located around the opening. The outer peripheral edge of the support 15 is fixed to the gas tank 16 by a fixing material 21 filled in the groove 16a of the gas tank 16.

[0044] In the example shown in Fig. 2A, fuel gas is stored in an internal space 22 formed by a support body 15, which is the support member 14, and a gas tank 16. A gas circulation pipe 20 is connected to the gas tank 16. The fuel gas is supplied to the gas tank 16 through this gas circulation pipe 20, and is supplied from the gas tank 16 to a gas flow path 2a (see Fig. 1A) inside the cell 1. The fuel gas supplied to the gas tank 16 is generated in a reformer 102 (see Fig. 8), which will be described later.

[0045] The hydrogen-rich fuel gas can be produced by steam reforming of the raw fuel, etc. When the fuel gas is produced by steam reforming, the fuel gas contains water vapor.

[0046] The example shown in FIG. 2A includes two rows of cell stacks 11 each having a plurality of cells 1, two supports 15, and a gas tank 16. The two rows of cell stacks 11 are fixed to the supports 15. The gas tank 16 has two through holes on the upper surface. A support 15 is disposed in each of the through holes. An internal space 22 is formed by the one gas tank 16 and the two supports 15.

[0047] The shape of the insertion hole 15a is, for example, an oval shape when viewed from above. For example, the length of the insertion hole 15a in the arrangement direction of the cells 1, i.e., the thickness direction T, is greater than the distance between the two end current collecting members 17 located at both ends of the cell stack 11. The width of the insertion hole 15a is, for example, greater than the length of the cell 1 in the width direction W (see FIG. 1A). The shape of the insertion hole 15a may be a substantially rectangular shape that is long in the arrangement direction of the cells 1.

[0048] 2B, a bonding material 13 is filled and solidified at the joint between the inner wall of the insertion hole 15a and the lower end of the cell 1. This bonds and fixes the inner wall of the insertion hole 15a and the lower end of each of the cells 1, and also bonds and fixes the lower ends of the cells 1 to each other. The gas flow path 2a of each cell 1 communicates with the internal space 22 of the support member 14 at its lower end.

[0049] A material having low electrical conductivity, such as glass, can be used for the bonding material 13 and the fixing material 21. Specific materials for the bonding material 13 and the fixing material 21 include amorphous glass, and in particular, crystallized glass.

[0050] As the crystallized glass, for example, any of materials such as SiO2-CaO, MgO-B2O3, La2O3-B2O3-MgO, La2O3-B2O3-ZnO, and SiO2-CaO-ZnO may be used, and in particular, SiO2-MgO-based materials may be used.

[0051] 2B, a conductive member 18 is interposed between adjacent cells 1 among the multiple cells 1. The conductive member 18 electrically connects the fuel electrode 5 of one adjacent cell 1 to the air electrode 8 of the other cell 1 in series. More specifically, the conductive member 18 connects the interconnector 4 electrically connected to the fuel electrode 5 of one adjacent cell 1 to the air electrode 8 of the other cell 1.

[0052] As shown in Fig. 2B, an end current collecting member 17 is electrically connected to the cell 1 located at the outermost position in the arrangement direction of the multiple cells 1. The end current collecting member 17 is connected to a conductive part 19 protruding to the outside of the cell stack 11. The conductive part 19 collects electricity generated by power generation in the cells 1 and draws it out to the outside. Note that the end current collecting member 17 is not shown in Fig. 2A.

[0053] 2C, the cell stack device 10 has two cell stacks 11A and 11B connected in series to function as one battery. Therefore, the conductive portion 19 of the cell stack device 10 is divided into a positive terminal 19A, a negative terminal 19B, and a connection terminal 19C.

[0054] The positive electrode terminal 19A is a positive electrode when the electric power generated by the cell stack 11 is output to the outside, and is electrically connected to the end current collecting member 17 on the positive electrode side of the cell stack 11A. The negative electrode terminal 19B is a negative electrode when the electric power generated by the cell stack 11 is output to the outside, and is electrically connected to the end current collecting member 17 on the negative electrode side of the cell stack 11B.

[0055] The connection terminal 19C electrically connects the end current collecting member 17 on the negative electrode side in the cell stack 11A and the end current collecting member 17 on the positive electrode side in the cell stack 11B.

[0056] <First Modification> Fig. 3 is a cross-sectional view showing an example of a cell according to a first modified example of the first embodiment. The element unit 3 shown in Fig. 3 differs from the element unit 3 shown in Fig. 1A in that parts 35 and 36 located at both ends in the width direction W have a concave outer surface 3a having a greater length in the thickness direction T than part 34 located in the center of the width direction W.

[0057] In this way, by making the outer surface 3a of the element part 3 concave when viewed in the length direction L (see, for example, FIG. 1C) perpendicular to the width direction W, the contact area between the oxygen-containing gas flowing around the element part 3 and the outer surface 3a is further increased, making it easier to take in the oxygen-containing gas inside the air electrode 8. This further improves the reactivity of the element part 3, and further improves the battery performance of the cell 1.

[0058] <Second Modification> Fig. 4 is a longitudinal sectional view showing an example of a cell according to a second modified example of the first embodiment. The cell 1 shown in Fig. 4 differs from the cell 1 shown in Fig. 1C in that both ends of the support substrate 2 located at both ends in the length direction L are bent in the thickness direction T toward the element portion 3. Note that in Fig. 4, the interconnector 4 located on the surface n2 of the support substrate 2 is omitted from illustration.

[0059] 4, the surface n1 of the support substrate 2 facing the element portion 3 has a concave curved surface corresponding to the outer surface 3a of the element portion 3. For this reason, the outer surface 3a can be made concave without adjusting the thickness of the element portion 3 over the entire length direction L. Furthermore, by making the outer surface 3a of the element portion 3 concave, the contact area between the oxygen-containing gas flowing around the element portion 3 and the outer surface 3a is increased, making it easier to take in the oxygen-containing gas inside the air electrode 8, thereby improving the battery performance of the cell 1.

[0060] <Third Modification> Fig. 5 is a cross-sectional view showing an example of a cell according to a third modified example of embodiment 1. The cell 1 shown in Fig. 5 differs from the cell 1 shown in Fig. 1A and Fig. 3 in that the side surfaces m of the support substrate 2 located at both ends in the width direction W are bent in the thickness direction T toward the element portion 3.

[0061] 5, the surface n1 of the support substrate 2 facing the element portion 3 has a concave curved surface corresponding to the outer surface 3a of the element portion 3. Therefore, the outer surface 3a of the element portion 3 can be made concave when viewed from the length direction L (see, for example, FIG. 1C) perpendicular to the width direction W without adjusting the thickness of the element portion 3 throughout the length direction L. Furthermore, by making the outer surface 3a of the element portion 3 concave, the contact area between the oxygen-containing gas flowing around the element portion 3 and the outer surface 3a is further increased, making it easier to take in the oxygen-containing gas inside the air electrode 8, thereby improving the battery performance of the cell 1.

[0062] <Fourth Modification> Fig. 6 is a longitudinal sectional view showing an example of a cell according to a fourth modified example of the first embodiment. The cell 1 shown in Fig. 6 differs from each of the cells 1 described above in that the surface n1 of the support substrate 2 facing the element portion 3 has a concave curved surface.

[0063] 6, the surface n1 of the support substrate 2 facing the element portion 3 has a concave curved surface corresponding to the outer surface 3a of the element portion 3. For this reason, the outer surface 3a can be made concave without adjusting the thickness of the element portion 3 over the entire length direction L. Furthermore, by making the outer surface 3a of the element portion 3 concave, the contact area between the oxygen-containing gas flowing around the element portion 3 and the outer surface 3a is increased, making it easier to take in the oxygen-containing gas inside the air electrode 8, thereby improving the battery performance of the cell 1.

[0064] <Fifth Modification> Fig. 7A is a longitudinal sectional view showing an example of a cell according to a fifth modified example of embodiment 1. An outer surface 3a of an element unit 3 of a cell 1 shown in Fig. 7A has a concavely inclined concave surface 37 and a flat surface 38 located upstream of the concave surface 37 in the oxygen-containing gas flow direction.

[0065] 7A, the concave curved surface 37 is positioned such that the thickness of the element part 3 increases from the upstream side to the downstream side of the oxygen-containing gas. On the other hand, the flat surface 38 is positioned such that the thickness of the element part 3 is uniform from the upstream side to the downstream side of the oxygen-containing gas.

[0066] In this way, because the outer surface 3a of the element unit 3 has the concave curved surface 37 and the flat surface 38, the oxygen-containing gas flowing around the element unit 3 from the flat surface 38 toward the concave curved surface 37 moves quickly near the flat surface 38 without being interfered with by the element unit 3, while the contact area between the oxygen-containing gas flowing around the concave curved surface 37 and the outer surface 3a increases, making it easier to take in the oxygen-containing gas inside the air electrode 8. This improves the battery performance of the cell 1.

[0067] Next, a configuration example of a cell stack having a plurality of cells 1 shown in Fig. 7A will be described. Fig. 7B is a vertical cross-sectional view showing an example of a cell stack including the cell shown in Fig. 7A.

[0068] The left side of Fig. 7B shows a cell stack 11 in which the length direction L (see Fig. 7A) of the cell 1 is arranged perpendicular to the arrangement direction of the multiple cells 1, and one end of the support substrate 2 is fixed with a bonding material 13. On the other hand, as shown on the right side of Fig. 7B, a cell stack 11a in which the multiple cells 1 are fixed obliquely with respect to the arrangement direction may also be used.

[0069] In this way, by fixing the multiple cells 1 at an angle to the arrangement direction, the contact area between the oxygen-containing gas flowing around the element portion 3 and the outer surface 3a (see FIG. 7A) is increased, making it easier to take in the oxygen-containing gas inside the air electrode 8 (see FIG. 7A). This improves the battery performance of the cells 1.

[0070] Although Fig. 7B shows the cell stack 11, 11a including the cell 1 shown in Fig. 7A, the cell stack 11, 11a may be a cell stack to which the cell 1 according to each of the above-mentioned embodiments and modifications is applied. Also, the cell stack 11, 11a may have at least one cell 1 according to each of the above-mentioned embodiments and modifications among the multiple cells arranged therein.

[0071] <module> Next, a module 100 according to an embodiment of the present disclosure using the above-mentioned cell stack device 10 will be described with reference to Fig. 8. Fig. 8 is an external perspective view showing the module according to the embodiment, with the front and rear surfaces, which are part of the storage container 101, removed and the cell stack device 10 of the fuel cell stored inside removed to the rear.

[0072] 8, the module 100 includes a storage container 101 and a cell stack device 10 housed in the storage container 101. In addition, above the cell stack device 10, a reformer 102 is disposed.

[0073] The reformer 102 reforms raw fuel such as natural gas or kerosene to generate fuel gas and supplies it to the cell 1. The raw fuel is supplied to the reformer 102 through a raw fuel supply pipe 103. The reformer 102 may include a vaporizer 102a that vaporizes water, and a reformer 102b. The reformer 102b includes a reforming catalyst (not shown) and reforms the raw fuel into fuel gas. Such a reformer 102 can perform steam reforming, which is a highly efficient reforming reaction.

[0074] The fuel gas generated in the reformer 102 is supplied to the gas flow channel 2a of the cell 1 (see FIG. 1A) through the gas distribution pipe 20, the gas tank 16, and the support member 14.

[0075] Furthermore, in the module 100 having the above-mentioned configuration, the temperature inside the module 100 during normal power generation becomes approximately 500 to 1000° C. as the gas is combusted and the cells 1 generate power.

[0076] In such a module 100, as described above, by housing the cell stack device 10 that improves the battery performance, the module 100 can be made to improve the battery performance.

[0077] <Module storage device> Fig. 9 is an exploded perspective view showing an example of a module housing device according to an embodiment. A module housing device 110 according to an embodiment includes an outer case 111, the module 100 shown in Fig. 8, and auxiliary equipment (not shown). The auxiliary equipment operates the module 100. The module 100 and the auxiliary equipment are housed in the outer case 111. Note that some components are omitted in Fig. 9.

[0078] An exterior case 111 of a module accommodating device 110 shown in Fig. 9 has support columns 112 and an exterior plate 113. A partition plate 114 divides the interior of the exterior case 111 into upper and lower sections. The space above the partition plate 114 in the exterior case 111 is a module accommodating chamber 115 that accommodates the module 100, and the space below the partition plate 114 in the exterior case 111 is an auxiliary equipment accommodating chamber 116 that accommodates auxiliary equipment that operates the module 100. Note that in Fig. 9, the auxiliary equipment accommodated in the auxiliary equipment accommodating chamber 116 is omitted.

[0079] In addition, the partition plate 114 has an air flow port 117 for allowing air from the auxiliary equipment housing chamber 116 to flow toward the module housing chamber 115. The exterior plate 113 constituting the module housing chamber 115 has an exhaust port 118 for exhausting air from within the module housing chamber 115.

[0080] In such a module accommodating device 110, as described above, by accommodating the module 100 that improves the battery performance in the module accommodating chamber 115, the module accommodating device 110 can be made to improve the battery performance.

[0081] [Second embodiment] Next, a cell stack device and a cell according to a second embodiment will be described with reference to Fig. 10A and Fig. 10B. Fig. 10A is a cross-sectional view showing an example of a cell according to the second embodiment. Fig. 10B is a cross-sectional view showing an example of a cell stack including the cell shown in Fig. 10A.

[0082] 10A, the cell 1A according to the second embodiment includes a support substrate 2, a pair of element units 3, and a sealing unit 9. The support substrate 2 is columnar having a pair of opposing surfaces n1, n2 and a pair of arc-shaped side surfaces m connecting the surfaces n1, n2.

[0083] The pair of element portions 3 are located opposite each other on the surfaces n1, n2 of the support substrate 2. The sealing portion 9 is located so as to cover the side surface m of the support substrate 2.

[0084] 10B, in the cell stack device 10A, a plurality of support substrates 2 supporting a plurality of element units 3 extend in the length direction L from a pipe 22a through which fuel gas flows, and each element unit 3 and the corresponding support substrate 2 constitutes a cell 1A. A gas flow path 2a through which gas flows from the pipe 22a is provided inside the support substrate 2. The cells 1A are connected in series via a conductive member (not shown).

[0085] 10A and 10B, each element unit 3 has a concave outer surface 3a located at the outermost air electrode 8. This makes it easier for the oxygen-containing gas flowing around each element unit 3 from the lower end side to the upper end side of the support substrate 2 to be taken into the air electrode 8. This improves the reactivity of the element unit 3 and improves the battery performance of the cell 1A, thereby improving the battery performance of the cell stack device 10A.

[0086] <Modification> Fig. 11 is a cross-sectional view showing an example of a cell according to a modified example of the second embodiment. The element unit 3 shown in Fig. 11 differs from the element unit 3 shown in Fig. 10A in that it has a pair of concave outer surfaces 3a whose lengths in the thickness direction T are greater at both ends in the width direction W than at the center portion in the width direction W.

[0087] In this way, by making the outer surface 3a of the element portion 3 concave as viewed in the length direction L (see, for example, FIG. 10B) perpendicular to the width direction W, the contact area between the oxygen-containing gas flowing around the element portion 3 and the outer surface 3a is further increased, making it easier to take in the oxygen-containing gas inside the air electrode 8. This further improves the reactivity of the element portion 3, and further improves the battery performance of the cell 1.

[0088] 10A and 11, the outer surface 3a is made concave by varying the thickness of the air electrode 8, but the thickness of one or more of the elements other than the air electrode 8, i.e., the fuel electrode 5, the solid electrolyte layer 6, and the intermediate layer 7, may be made different. Furthermore, the surfaces n1 and n2 of the support substrate 2 may be made concave, thereby providing the outer surface 3a with a concave shape corresponding to the surfaces n1 and n2.

[0089] 10B shows a cell stack device 10A in which a plurality of cells 1A each having a plurality of element units 3 shown in FIG. 10A are arranged, but it is sufficient that at least one of the arranged cells includes a cell 1A according to the above-mentioned embodiment and modified example. Also, it is sufficient that at least one of the element units included in each cell 1A includes an element unit 3 according to the above-mentioned embodiment and modified example. Furthermore, instead of the element unit 3 according to the above-mentioned embodiment and modified example, for example, the element unit 3 included in the cell 1 shown in FIG. 6 and / or FIG. 7A may be applied.

[0090] [Third embodiment] Fig. 12A is a perspective view showing a flat cell according to the third embodiment, Fig. 12B is a cross-sectional view taken along line YY shown in Fig. 12A, and Fig. 12C is a cross-sectional view taken along line ZZ shown in Fig. 12B.

[0091] 12A to 12C, the cell 1C has an element portion 3 in which a fuel electrode 5, a solid electrolyte layer 6, and an air electrode 8 are stacked. In a cell stack device in which a plurality of flat plate type cells are stacked, for example, the plurality of cells 1C are electrically connected by conductive members 91, 92 which are adjacent metal layers. The conductive members 91, 92 electrically connect the adjacent cells 1C to each other, and have a gas flow path for supplying gas to the fuel electrode 5 or the air electrode 8.

[0092] In this modification, the conductive member 92 has a plurality of gas flow paths 93 that supply an oxygen-containing gas to the air electrode 8. The plurality of gas flow paths 93 each extend along a first direction D1, and are positioned at predetermined intervals in a second direction D2 that intersects with the first direction D1.

[0093] The conductive member 92 is bonded to the outer surface 3a of the element portion 3 (air electrode 8) via a bonding material 94. Since the outer surface 3a of the element portion 3 faces the gas flow passage 93 in this manner, the contact area between the oxygen-containing gas flowing through the gas flow passage 93 and the outer surface 3a is increased, making it easier to take in the oxygen-containing gas into the air electrode 8. This further improves the reactivity of the element portion 3, improving the battery performance of the cell 1C.

[0094] <Other Modifications> Next, cell stack devices according to other modified examples of the embodiment will be described.

[0095] In the above embodiment, a case where a hollow flat support substrate is used is exemplified, but the present invention can also be applied to a cell stack device that uses a cylindrical support substrate.

[0096] In addition, in the above embodiment, an example was shown in which the fuel electrode was provided on the support substrate and the air electrode was arranged on the surface of the cell, but the present invention can also be applied to a cell stack device in which the opposite arrangement is used, i.e., in which the air electrode is provided on the support substrate and the fuel electrode is arranged on the surface of the cell.

[0097] In addition, in the above embodiments, a fuel cell, a fuel cell stack device, a fuel cell module and a fuel cell device are shown as examples of a "cell," a "cell stack device," a "module" and a "module accommodating device," but other examples may be an electrolytic cell, an electrolytic cell stack device, an electrolytic module and an electrolytic device, respectively.

[0098] Although the present disclosure has been described in detail above, the present disclosure is not limited to the above-described embodiments, and various modifications, improvements, etc. are possible without departing from the gist of the present disclosure.

[0099] As described above, the cell 1 according to the embodiment includes the element section 3. The element section 3 has a first electrode (fuel electrode 5) and a second electrode (air electrode 8). The element section 3 has a concave outer surface 3a on the surface of the second electrode located on the opposite side to the first electrode. This can improve the battery performance.

[0100] Moreover, the module 100 according to the embodiment includes the cell stack device 10 described above, and a storage container 101 that stores the cell stack device 10. This makes it possible to provide the module 100 with improved battery performance.

[0101] Moreover, the module housing device 110 according to the embodiment includes the above-described module 100, an auxiliary device for operating the module 100, and an exterior case 111 for housing the module 100 and the auxiliary device. This allows the module housing device 110 to improve battery performance.

[0102] The disclosed embodiments should be considered to be illustrative and not restrictive in all respects. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0103] 1 cell 10 Cell stack device 11 Cell stack 12 Fixing member 13 Bonding material 14 Support member 15 Support 16 Gas Tank 17 End current collecting member 18 Conductive materials 100 Modules 110 Module storage device

Claims

1. An element portion having a first electrode and a second electrode, the element portion has a concave outer surface on a surface of the second electrode opposite to the first electrode, the outer surface has a flat surface located on the upstream side of a second gas flow passage through which a second reactant gas supplied to the second electrode flows, and a concavely curved surface located on the downstream side of the flat surface in the second gas flow passage and inclined in a concave shape, The thickness of the second electrode where the concave surface is located is greater than the thickness of the second electrode where the flat surface is located. cell.

2. The outer surface has a first portion and a second portion that is located closer to at least a part of the outer periphery of the second electrode than the first portion in a plan view of the second electrode, and the thickness of the element portion is greater than that of the first portion. The cell of claim 1 .

3. the second electrode has a first outer periphery and a second outer periphery opposed to each other in a plan view, The flat surface is located closer to the second outer periphery than the concave surface. A cell according to claim 1 or 2.

4. A cell stack in which a plurality of cells are arranged, At least one of the plurality of cells is a cell according to any one of claims 1 to 3. Cell stack device.

5. a cell stack in which a plurality of cells are arranged and which has a second gas flow path between the plurality of cells through which a second reactant gas flows; At least one of the plurality of cells is the cell according to claim 2, and the second portion is located downstream of the first portion in the second gas flow path. Cell stack device.

6. The outer surface has a third portion located upstream of the second gas flow path relative to the first portion, and the thickness of the element portion is greater than that of the first portion. The cell stack device according to claim 5 .

7. The second reactive gas is an oxygen-containing gas. The cell stack device according to claim 5 or 6.

8. The cells are fixed obliquely to the direction in which the cells are arranged. The cell stack device according to any one of claims 4 to 7.

9. A cell stack device according to any one of claims 4 to 8, a storage container for storing the cell stack device; A module comprising:

10. A module according to claim 9; Auxiliary equipment for operating the module; an exterior case that houses the module and the auxiliary equipment; A module housing device comprising:

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