Electrochemical cell, electrochemical cell device, module, and module storage device

Abstract

An electrochemical cell disclosed herein comprises a metal body, an element part, and an encapsulation part. The element part includes a solid electrolyte layer and a first electrode including a first material. The encapsulation part is in contact with the first electrode and the metal body around the element part, and includes a seal material. The first electrode is located at a boundary with the encapsulation part, and has a first portion including the first material and the seal material. The first portion includes a first porous material.

Description

Electrochemical cell, electrochemical cell device, module, and module housing device

[0001] The present disclosure relates to electrochemical cells, electrochemical cell devices, modules and module housing devices.

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

[0003] Japanese Patent Application Laid-Open No. 2020-72002

[0004] An electrochemical cell according to one aspect of the embodiment includes a metal body, an element unit, and a sealing unit. The element unit includes a solid electrolyte layer and a first electrode including a first material. The sealing unit contacts the first electrode around the periphery of the element unit and includes a sealing material. The first electrode has a first portion located at the boundary with the sealing unit and including the first material and the sealing material. The first portion includes a first porous portion.

[0005] An electrochemical cell according to one aspect of the embodiment includes a metal substrate, an element portion, an intermediate layer, and a sealing portion. The intermediate layer is located between the metal substrate and the element portion and includes a second material. The sealing portion is located around the element portion and includes a sealing material. The intermediate layer is located at a boundary portion in contact with the sealing portion and has a porous second portion including the second material and the sealing material.

[0006] An electrochemical cell device according to one aspect of the embodiment includes a cell stack including the electrochemical cell described above.

[0007] The module of the present disclosure also includes the electrochemical cell device described above and a container that houses the electrochemical cell device.

[0008] The module housing device of the present disclosure also includes the module described above, an accessory configured to operate the module, and an exterior case housing the module and the accessory.

[0009] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. FIG. 1B is a plan view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 2 is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 3 is a cross-sectional view taken along line A-A in FIG. 1B. FIG. 4A is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 4B is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 4C is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 4D is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 4E is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 5A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. FIG. 5B is a cross-sectional view taken along line X-X in FIG. 5A. FIG. 5C is a top view showing an example of an electrochemical cell device according to the first embodiment. FIG. 6 is an external perspective view showing an example of a module according to the first embodiment. FIG. 7 is an exploded perspective view schematically showing an example of a module housing device according to the first embodiment. Fig. 8 is a perspective view showing an example of an electrochemical cell according to a second embodiment, Fig. 9 is a partial cross-sectional view of the electrochemical cell shown in Fig. 8, and Fig. 10 is an enlarged cross-sectional view of a region R1 shown in Fig. 9.

[0010] The above-described fuel cell stack device has room for improvement in terms of durability.

[0011] Therefore, there is a need to provide an electrochemical cell, an electrochemical cell device, a module, and a module housing device that can improve durability.

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

[0013] It should also be noted that the drawings are schematic and that the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may contain parts whose dimensional relationships and ratios differ from one another.

[0014] [First embodiment] <Configuration of electrochemical cell> First, an electrochemical cell according to a first embodiment will be described using an example of a solid oxide fuel cell with reference to Figures 1A and 1B. The electrochemical cell device may include a cell stack having a plurality of electrochemical cells. An electrochemical cell device having a plurality of electrochemical cells will be simply referred to as a cell stack device.

[0015] Fig. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. Fig. 1B is a plan view of the example of the electrochemical cell according to the first embodiment, viewed from the air electrode side. Note that Figs. 1A and 1B show enlarged views of parts of each component of the electrochemical cell. Hereinafter, the electrochemical cell may also be simply referred to as a cell.

[0016] For ease of understanding, Fig. 1A illustrates a three-dimensional Cartesian coordinate system including a Z-axis, with the vertically upward direction being the positive direction and the vertically downward direction being the negative direction. This Cartesian coordinate system may also be illustrated in other drawings used in the following description. Furthermore, components similar to those in the electrochemical cell illustrated in Fig. 1A are denoted by the same reference numerals, and their description will be omitted or simplified.

[0017] As shown in Fig. 1A, the cell 1 according to this embodiment includes an element unit 3, an intermediate layer 4, a metal substrate 32, and a flow path member 34. The element unit 3 includes an anode 5, a solid electrolyte layer 6, and a cathode 8. In the example of Fig. 1A, one element unit 3 is located on the metal substrate 32, but two or more element units 3 may be located thereon.

[0018] The anode 5 is a first electrode that comes into contact with the fuel gas, which is a reducing gas. The anode 5 has gas permeability. The open porosity of the anode 5 may be, for example, in the range of 30% to 50%, particularly 35% to 45%. The open porosity of the anode 5 may also be referred to as the porosity or void ratio of the anode 5.

[0019] A generally known material can be used for the fuel electrode 5. The fuel electrode 5 is made of a porous conductive ceramic, such as calcium oxide, magnesium oxide, or ZrO in which a rare earth element oxide is solid-solved. ２and Ni and / or NiO may be used. The rare earth element oxide may contain, for example, a plurality of rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. Calcium oxide, magnesium oxide, or ZrO in which a rare earth element oxide is solid-solved may be used. ２ The stabilized zirconia may contain partially stabilized zirconia. The anode 5 is made of CeO in which La, Nd, or Yb is solid-solved. ２ may include:

[0020] The anode 5 also has a first portion 51. The first portion 51 contains the same material as the sealing portion 9, which will be described later. This makes it less likely for the anode 5 and the sealing portion 9 to peel off, thereby improving the durability of the cell 1. The detailed configuration of the first portion 51 and its vicinity will be described later.

[0021] The solid electrolyte layer 6 is an electrolyte and transfers 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.

[0022] The material of the solid electrolyte layer 6 is, for example, ZrO in which 3 mol % to 15 mol % of rare earth element oxide is dissolved. ２ The rare earth element oxide may contain, for example, one or more rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. The solid electrolyte layer 6 may be, for example, ZrO in which Yb, Sc, or Gd is solid-solved. ２ and CeO in which La, Nd or Yb is solid-solved. ２ and BaZrO in which Sc or Yb is solid-solved. ３ and BaCeO in which Sc or Yb is solid-solved. ３ may include:

[0023] The air electrode 8 is a second electrode that comes into contact with an oxygen-containing gas. The air electrode 8 has gas permeability. The open porosity of the air electrode 8 may be, for example, in the range of 20% to 50%, particularly 30% to 50%. The open porosity of the air electrode 8 may also be referred to as the porosity of the air electrode 8.

[0024] There are no particular limitations on the material of the air electrode 8 as long as it is a material that is generally used for air electrodes. ３ Conductive ceramics such as perovskite oxides may also be used.

[0025] The material of the air electrode 8 may be, for example, a composite oxide in which Sr (strontium) and La (lanthanum) coexist at the A site. Examples of such composite oxides include La ｘ Sr １－ｘ Co ｙ Fe １－ｙ O ３ , La ｘ Sr １－ｘ MnO ３ , La ｘ Sr １－ｘ FeO ３ , La ｘ Sr １－ｘ CoO ３ Here, x is 0<x<1, and y is 0<y<1.

[0026] The element section 3 may also have a diffusion suppression layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. When a specific element such as Sr (strontium) contained in the air electrode 8 diffuses into the solid electrolyte layer 6, the solid electrolyte layer 6 is covered with SrZrO ３ The diffusion suppression layer makes it difficult for specific elements such as Sr to diffuse, resulting in a resistive phase such as SrZrO ３ This makes it difficult for compounds such as

[0027] The material of the diffusion-preventing layer is not particularly limited as long as it is generally Sr or the like and makes it difficult for elements to diffuse between the solid electrolyte layer 6 and the air electrode 8. The material of the diffusion-preventing layer is, for example, cerium oxide (CeO) in which rare earth elements other than Ce (cerium) are dissolved. ２ ) may be included. Examples of such rare earth elements include Gd (gadolinium) and Sm (samarium).

[0028] The intermediate layer 4 is located between the first surface 321 of the metal base 32 and the element portion 3. The intermediate layer 4 bonds the element portion 3 and the metal base 32 together, and fixes the element portion 3 to the metal base 32.

[0029] The intermediate layer 4 is conductive. For example, the intermediate layer 4 is made of conductive particles such as Ni and TiO ２ , rare earth element oxides (Y ２ O ３ , CeO ２ etc.), transition metal oxides (Fe ２ O ３ The inorganic oxide may include inorganic oxides such as SiO 2 , CuO, etc.

[0030] The intermediate layer 4 has gas permeability. The intermediate layer 4 may be positioned so as to cover an opening 32a, which will be described later.

[0031] The intermediate layer 4 may be formed as a single layer using a single material, or may be formed as a laminate of a plurality of materials.

[0032] Sealing portions 9, which are different from the solid electrolyte layer 6, are located on the side surfaces of the intermediate layer 4 and the element portion 3. The material of the sealing portion 9 may be dense glass or ceramic. The material of the sealing portion 9 may be, for example, amorphous glass or crystallized glass. Examples of crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO-based, La ２ O ３ -B ２ O ３ -ZnO-based, SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２ The sealing portion 9 may be made of the same material as the solid electrolyte layer 6.

[0033] The metal base 32 has a first surface 321 and a second surface 322 located at opposite ends in the thickness direction (Y-axis direction). The metal base 32 is an example of a metal body. The metal base 32 may be, for example, a plate-shaped metal body in which the distance between the first surface 321 and the second surface 322 is substantially constant, i.e., a metal plate.

[0034] The metal substrate 32 is electrically conductive. The metal substrate 32 may be, for example, a member made of a metal containing chromium. The metal substrate 32 may be, for example, a stainless steel such as a ferritic stainless steel or an austenitic stainless steel having high heat resistance. The metal substrate 32 may be, for example, a nickel-chromium alloy or an iron-chromium alloy. The metal substrate 32 may contain, for example, a metal oxide. The metal substrate 32 may have a coating covering the surface. The metal substrate 32 does not have to have a coating on the surface.

[0035] The metal base 32 also has an opening 32a. The opening 32a is a through-hole that penetrates between the first surface 321 and the second surface 322. The fuel gas flowing through a flow path 33 (described later) is supplied to the fuel electrode 5 of the element section 3 through the opening 32a. The diameter of the opening 32a may be, for example, 0.1 mm to 0.5 mm, particularly 0.3 mm to 0.4 mm. In a plan view of the metal base 32 along the Y-axis direction, the aperture ratio of the region where the opening 32a is formed may be, for example, 10% or more. The metal base 32 may have a coating that covers the wall surface of the opening 32a. The metal base 32 may not have a coating on the wall surface of the opening 32a.

[0036] The metal substrate 32 may be gas permeable, for example. In such a case, the metal substrate 32 does not need to have the opening 32a.

[0037] The flow path member 34 is located on the second surface 322 side of the metal substrate 32. The flow path member 34 is fixed and electrically joined by, for example, welding or the like at the contact portion with the second surface 322. The flow path member 34 may be fixed and electrically joined to the metal substrate 32 with a conductive sealing material, brazing material, or the like. The space located between the metal substrate 32 and the flow path member 34 is a flow path 33 through which the fuel gas flows. The fuel gas flowing through the flow path 33 permeates the metal substrate 32 and is supplied to the anode 5. The metal substrate 32 may have one or more protrusions protruding toward the flow path member 34.

[0038] The flow path member 34 is further fixed and electrically joined to the current collecting member 36 by welding or the like. The current collecting member 36 may be fixed and electrically joined to the flow path member 34 by a conductive sealing material, brazing material, or the like. The current collecting member 36 may be fixed and electrically joined to the air electrode 8 of an adjacent cell 1 via an adhesive (not shown). The space located between the current collecting member 36 and the flow path member 34 is a flow path 35 through which an oxygen-containing gas flows. The oxygen-containing gas flowing through the flow path 35 passes through the adhesive from the slits in the current collecting member 36 and is supplied to the air electrode 8 of the adjacent cell 1.

[0039] The flow path member 34 and the current collecting member 36 are made of a dense metal or alloy. The flow path member 34 makes it difficult for the fuel gas flowing through the flow path 33 and the oxygen-containing gas flowing through the flow path 35 to leak. The flow path member 34 and the current collecting member 36 may have a coating. For example, the surface of the flow path member 34 facing the flow path 33 may have a reduction-resistant coating. Furthermore, the surface of the flow path member 34 facing the flow path 35 may have an oxidation-resistant coating. These coatings may be conductive.

[0040] The shapes of the flow path member 34 and the current collecting member 36 are not limited to those shown in Fig. 1A. The flow path member 34 and the current collecting member 36 may have any shape as long as they electrically connect adjacent cells 1 and make it difficult for the fuel gas and oxygen-containing gas to leak.

[0041] 2 is a cross-sectional view showing another example of the electrochemical cell according to the first embodiment. As shown in Fig. 2, for example, the flow path member 34 may be integrated with the current collecting member 36 and have a first convex portion that protrudes toward the adjacent cell 1 along the Y-axis direction and a second convex portion that protrudes toward the opposite side from the first convex portion.

[0042] The cell 1 may further include a constraining layer (not shown). The constraining layer may be located between the element portion 3 and the metal substrate 32. The constraining layer cooperates with the solid electrolyte layer 6 to make the element portion 3 less susceptible to warping, bending, and the like.

[0043] The material of the constraining layer exhibits a shrinkage rate similar to that of the material of the solid electrolyte layer 6 during firing. The material of the constraining layer may be the same as the material of the solid electrolyte layer 6. The element unit 3 obtained by sandwiching the material of the anode 5 of the element unit 3 between the material of the solid electrolyte layer 6 and the material of the constraining layer and firing the resulting element unit 3 has little warping or deformation.

[0044] The constraining layer may or may not be gas permeable. When the constraining layer has gas barrier properties comparable to those of the solid electrolyte layer 6, the constraining layer can be partially disposed so as not to obstruct the inflow of fuel gas to the anode 5.

[0045] <Arrangement and Structure of First Region and Its Surrounding Area> Next, the arrangement and structure of the first region and its surrounding area will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view taken along line AA shown in Fig. 1B.

[0046] As shown in FIG. 3, the cell 1 includes a metal substrate 32 , a sealing portion 9 , an element portion 3 , and an intermediate layer 4 .

[0047] The sealing portion 9 is in contact with the metal substrate 32. The sealing portion 9 is in contact with the solid electrolyte layer 6 and the fuel electrode 5 of the element portion 3. The sealing portion 9 may be separated from the air electrode 8 or may be in contact with the air electrode 8. For example, a portion of the sealing portion 9 surrounding the periphery of the peripheral surfaces 8a to 8d located at the end of the air electrode 8 in the plan view shown in FIG. 1B may be in contact with the air electrode 8. The sealing portion 9 includes a sealing material 90. The sealing material 90 may be, for example, glass such as crystallized glass or amorphous glass, or a brazing material.

[0048] The element unit 3 includes a solid electrolyte layer 6, a fuel electrode 5 as a first electrode, and a cathode 8 as a second electrode. The solid electrolyte layer 6 has a first surface 61 facing the metal substrate 32 and a second surface 62 located on the opposite side of the first surface 61.

[0049] The fuel electrode 5 is located between the first surface 61 of the solid electrolyte layer 6 and the metal substrate 32. The air electrode 8 is located so as to face the second surface 62.

[0050] The anode 5 includes a first material m1. The first material m1 is, for example, ZrO containing Ni (nickel) and / or a rare earth element.２ The rare earth element may be, for example, at least one of rare earth elements such as Y (yttrium), Yb (ytterbium), Ce (cerium), and Gd (gadolinium).

[0051] The first material m1 may include a plurality of first metal particles P1 and a plurality of first inorganic oxide particles P2. The first metal particles P1 may be, for example, Ni (nickel). The first inorganic oxide particles P2 may be, for example, ZrO containing an oxide of a rare earth element. ２ may be.

[0052] The anode 5 has a first portion 51. The first portion 51 is located at the boundary with the sealing portion 9. The first portion 51 includes a first material m1 and a sealing material 90. The first portion 51 includes a first porous portion. The porosity of the first porous portion included in the first portion 51 may be in the range of, for example, 30% to 50%, particularly 35% to 45%.

[0053] As described above, the anode 5 has a first porous portion in the first region 51 located at the boundary with the sealing portion 9. The first region 51 contains both the first material m1 contained in the anode 5 and the sealing material 90 contained in the sealing portion 9. This reduces the likelihood of cracking the sealing portion 9 and / or peeling of the sealing portion 9 from the anode 5 due to the difference in thermal expansion between the anode 5 and the sealing portion 9. This improves the durability of the cell 1 according to this embodiment. Furthermore, even if stress is generated due to the difference in thermal expansion between the anode 5 and the sealing portion 9, the stress can be alleviated by the first region 51 including the first porous portion. This allows the cell 1 according to this embodiment to exhibit higher durability.

[0054] The anode 5 may have an active portion 5a located on the first surface 61 side and a diffusion portion 5b located between the active portion 5a and the intermediate layer 4. When the anode 5 has the active portion 5a, the first portion 51 of the anode 5 may have a first portion 51a located at the boundary between the active portion 5a and the sealing portion 9 and including a first porous portion. When the anode 5 has the diffusion portion 5b, the first portion 51 of the anode 5 may have a first portion 51b located at the boundary between the diffusion portion 5b and the sealing portion 9 and including a first porous portion. The first portion 51 may have both the first portion 51a and the first portion 51b. The first portion 51 may have either the first portion 51a or the first portion 51b.

[0055] The intermediate layer 4 is located between the metal substrate 32 and the element portion 3. The intermediate layer 4 may include a second material m2. The second material m2 may include, for example, at least one of metals such as Ni (nickel), Cu (copper), Co (cobalt), Fe (iron), and Ti (titanium), or an alloy containing one or more of these metals, oxides of Ti, Zr (zirconium), Al (aluminum), Si (silicon), Mg (magnesium), Ca (calcium), Sr (strontium), and Ba (barium), and oxides of rare earth elements such as Y (yttrium), Yb (ytterbium), Ce (cerium), and Gd (gadolinium).

[0056] The second material m2 may include a plurality of second metal particles P3 and a plurality of second inorganic oxide particles P4. The second metal particles P3 may be, for example, Ni (nickel). The second inorganic oxide particles P4 may be, for example, titania.

[0057] The second material m2 may be the same as or different from the first material m1. The second metal particles P3 may be the same as or different from the first metal particles P1. The second inorganic oxide particles P4 may be the same as or different from the first inorganic oxide particles P2.

[0058] Next, another example of the cell 1 according to this embodiment will be described with reference to Figures 4A to 4E. Figures 4A to 4E are cross-sectional views showing another example of the electrochemical cell according to the first embodiment. Figures 4A to 4E correspond to the cross section AA shown in Figure 1B.

[0059] As shown in FIG. 4A , the first portion 51 may have a first region 511, which is a first porous portion, and a second region 512. The second region 512 may be located between the first region 511 and the sealing portion 9, be in contact with the sealing portion 9, and have a smaller porosity than the first region 511. This further reduces the likelihood of cracks in the sealing portion 9 and / or peeling of the sealing portion 9 from the anode 5, which may be caused by a difference in thermal expansion between the anode 5 and the sealing portion 9. Therefore, the cell 1 according to this embodiment has further improved durability. The porosity of the second region 512 may be, for example, 35% or less. The second region 512 does not necessarily have to include pores.

[0060] 4B , the sealing portion 9 may have a second porous portion 91 located at the boundary where it contacts the anode 5 serving as the first electrode. The second porous portion 91 may have a higher porosity than other portions of the sealing portion 9. This makes it even less likely that cracks will occur in the sealing portion 9 and / or the sealing portion 9 will peel off from the anode 5, which may be caused by the difference in thermal expansion between the anode 5 and the sealing portion 9. Therefore, the durability of the cell 1 according to this embodiment is further improved.

[0061] The porosity of the second porous portion 91 may be, for example, in the range of 10% to 50%. Furthermore, when the anode 5 has an active portion 5a, the second porous portion 91 of the sealing portion 9 may have a second porous portion 91a located at the boundary with the active portion 5a. When the anode 5 has a diffusion portion 5b, the second porous portion 91 of the sealing portion 9 may have a second porous portion 91b located at the boundary with the diffusion portion 5b. The second porous portion 91 may have both the second porous portion 91a and the second porous portion 91b. The second porous portion 91 may have either the second porous portion 91a or the second porous portion 91b.

[0062] 4C , the sealing portion 9 may further contain the first material m1. This means that the first material m1 is contained in both the anode 5 and the sealing portion 9. This makes it even less likely that cracks will occur in the sealing portion 9 and / or that the sealing portion 9 will peel off from the anode 5, which may be caused by a difference in thermal expansion between the anode 5 and the sealing portion 9, further improving the durability of the cell 1.

[0063] 4D , the intermediate layer 4 located between the fuel electrode 5 serving as the first electrode and the metal substrate 32 may have a second portion 41. The second portion 41 may be located at the boundary portion in contact with the sealing portion 9. The second portion 41 includes the second material m2 and a sealing material 90. The second portion 41 may include a third porous portion. The porosity of the third porous portion of the second portion 41 may be in the range of, for example, 30% to 50%, particularly 35% to 45%.

[0064] In this way, the second region 41 may have both the second material m2 contained in the intermediate layer 4 and the sealing material 90 contained in the plugging portion 9. The second region 41 may include a third porous portion. This makes it less likely that cracks will occur in the plugging portion 9 and / or that the plugging portion 9 will peel off from the intermediate layer 4, which may be caused by a difference in thermal expansion between the intermediate layer 4 and the plugging portion 9. Therefore, the cell 1 according to this embodiment has improved durability.

[0065] 4E, the element portion 3 may be located directly on the metal substrate 32 without the intermediate layer 4. The anode 5 may have a first portion 51 located at the boundary with the sealing portion 9 and including a first porous portion. The first portion 51 may have both the first material m1 contained in the anode 5 and the sealing material 90 contained in the sealing portion 9. This makes it less likely that cracks will occur in the sealing portion 9 and / or the sealing portion 9 will peel off from the anode 5 due to differences in thermal expansion between the anode 5 and the sealing portion 9. Therefore, the cell 1 according to this embodiment has improved durability.

[0066] The arrangement of the first material m1 containing the first metal particles P1 and the first inorganic oxide particles P2, the second material m2 containing the second metal particles P3 and the second inorganic oxide particles P4, and the sealing material 90, as well as the shapes of the first portion 51, the first region 511, the second region 512, and the second portion 41, are obtained as follows. For example, a polished cross section of the cell 1 containing the intermediate layer 4, the anode 5, and the sealing portion 9 can be measured by image analysis of a backscattered electron image using a scanning electron microscope (SEM) or a transmission electron microscope (TEM) and an energy dispersive X-ray analyzer (EDX). Specifically, the first material m1, the second material m2, and the sealing material 90 are identified in the backscattered electron image of the cross section by structural morphology and elemental analysis. By checking the arrangement or distribution of the determined first material m1, second material m2, and sealing material 90, it is possible to confirm the presence and shape of a first portion 51 containing both the first material m1 and the sealing material 90 and a second portion 41 containing both the second material m2 and the sealing material 90. Furthermore, in a backscattered electron image of the cross section, the presence or absence of a first region 511 and a second region 512 can be determined based on the porosity calculated by image analysis of the first portion 51.

[0067] The first metal particles P1 may have an average particle size (equivalent circle diameter) of 0.3 μm to 5 μm. The first inorganic oxide particles P2 may have an average particle size (equivalent circle diameter) of 0.3 μm to 5 μm. The second metal particles P3 may have an average particle size (equivalent circle diameter) of 2.5 μm to 5 μm. The second inorganic oxide particles P4 may have an average particle size (equivalent circle diameter) of 0.4 μm to 1.5 μm.

[0068] <Configuration of Electrochemical Cell Device> Next, an electrochemical cell device according to this embodiment using the above-described cell 1 will be described with reference to Figs. 5A to 5C. Fig. 5A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. Fig. 5B is a cross-sectional view taken along line XX shown in Fig. 5A. Fig. 5C is a top view showing an example of an electrochemical cell device according to the first embodiment.

[0069] As shown in Figure 5A, the cell stack device 10 includes a cell stack 11 having multiple cells 1 arranged (stacked) in the thickness direction of the cells 1 (the Y-axis direction shown in Figure 1A), and a fixing member 12.

[0070] The fixing member 12 has a fixing material 13 and a support member 14. The support member 14 supports the cell 1. The fixing material 13 fixes the cell 1 to the support member 14. The support member 14 also has a support 15 and a gas tank 16. The support 15 and the gas tank 16, which are the support member 14, are made of metal and are electrically conductive.

[0071] 5B, the support body 15 has insertion holes 15a into which the lower ends of the plurality of cells 1 are inserted. The lower ends of the plurality of cells 1 and the inner wall of the insertion holes 15a are joined with fixing material 13.

[0072] The gas tank 16 has an opening for supplying a reaction gas to the cells 1 through the insertion holes 15a, and a recessed groove 16a located around the opening. The outer peripheral edge of the support 15 is joined to the gas tank 16 by a bonding material 21 filled in the recessed groove 16a of the gas tank 16.

[0073] In the example shown in Fig. 5A, fuel gas is stored in an internal space 22 (see Fig. 5B) 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 flow path 33 (see Fig. 1A) inside the cell 1. The fuel gas supplied to the gas tank 16 may be generated in a reformer 102 (see Fig. 6), which will be described later. The internal space 22 may also be referred to as a space containing a reducing atmosphere and fuel gas.

[0074] The hydrogen-rich fuel gas can be produced by steam reforming the raw fuel, etc. When the fuel gas is produced by steam reforming, the fuel gas contains water vapor.

[0075] The example shown in FIG. 5A includes two rows of cell stacks 11, two supports 15, and a gas tank 16. Each of the two rows of cell stacks 11 includes a plurality of cells 1. Each cell stack 11 is fixed to a corresponding support 15. The gas tank 16 has two through-holes on its top surface. A support 15 is disposed in each through-hole. The internal space 22 is formed by the one gas tank 16 and the two supports 15. The cell stack device 10 may include only one cell stack 11, or may include three or more cell stacks 11.

[0076] The shape of the insertion hole 15a may be, 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 (Y-axis direction shown in FIG. 1A ), may be greater than the distance between the two end current collecting members 17 located at both ends of the cell stack 11. For example, the width of the insertion hole 15a may be greater than the length of the cell 1 in the width direction (X-axis direction shown in FIG. 1A ).

[0077] 5B, a fixing 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 to the lower end of each of the multiple 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.

[0078] A material with low conductivity, such as glass, can be used for the fixing material 13 and the bonding material 21. Specific materials for the fixing material 13 and the bonding material 21 include amorphous glass, and in particular, crystallized glass.

[0079] Examples of the crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO-based, La ２ O ３ -B ２ O ３ -ZnO-based, SiO ２-CaO-ZnO system materials, etc., may be used, and in particular SiO ２ - MgO-based materials may also be used.

[0080] 5B , a conductive member 18 is interposed between adjacent cells 1 among the plurality of cells 1. The conductive member 18 electrically connects one adjacent cell 1 to the other adjacent cell 1 in series. More specifically, the conductive member 18 connects the fuel electrode 5 of one cell 1 to the air electrode 8 of the other cell 1. The conductive member 18 may be the flow path member 34 or the current collecting member 36 shown in FIG. 1A , or may be a member separate from the flow path member 34 and the current collecting member 36.

[0081] 5B, 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 portion 19 that protrudes to the outside of the cell stack 11. The conductive portion 19 collects electricity generated by power generation in the cells 1 and extracts it to the outside. Note that the end current collecting member 17 is not shown in FIG. 5A.

[0082] 5C, the cell stack device 10 has two cell stacks 11A and 11B connected in series to function as a single 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.

[0083] The positive electrode terminal 19A is a positive electrode when the power generated by the cell stack 11 is output to the outside. The positive electrode terminal 19A is electrically connected to the end current collector 17 on the positive electrode side of the cell stack 11A. The negative electrode terminal 19B is a negative electrode when the power generated by the cell stack 11 is output to the outside. The negative electrode terminal 19B is electrically connected to the end current collector 17 on the negative electrode side of the cell stack 11B.

[0084] The connection terminal 19C electrically connects the end current collecting member 17 on the negative electrode side of the cell stack 11A to the end current collecting member 17 on the positive electrode side of the cell stack 11B.

[0085] <Module> Next, a module according to this embodiment using the above-described cell stack device 10 will be described with reference to Fig. 6. Fig. 6 is an external perspective view showing an example of a module according to the first embodiment. Fig. 6 shows a state in which the front and rear surfaces, which are part of the storage container 101, have been removed and the cell stack device 10 of the fuel cell stored inside has been taken out to the rear.

[0086] 6, the module 100 includes a cell stack device 10 and a storage container 101 that stores the cell stack device 10. A reformer 102 may be disposed above the cell stack device 10.

[0087] The reformer 102 reforms raw fuel such as natural gas or kerosene to generate fuel gas, which is then supplied 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, a highly efficient reforming reaction.

[0088] The fuel gas produced in the reformer 102 is supplied to the flow path 33 of the cell 1 (see FIG. 1A) through the gas distribution pipe 20, the gas tank 16, and the support member 14.

[0089] Furthermore, in the module 100 having the above-described configuration, the temperature inside the module 100 during normal power generation reaches approximately 500°C to 1000°C due to the combustion of gas and the power generation of the cells 1.

[0090] In such a module 100, as described above, the module 100 is configured to house the cell stack device 10 having a plurality of highly durable cells 1, thereby making it possible to make the module 100 highly durable.

[0091] <Module Enclosure Device> Fig. 7 is an exploded perspective view schematically illustrating an example of a module enclosure device according to the first embodiment. The module enclosure device 110 according to this embodiment includes an outer case 111, the module 100 shown in Fig. 6, and auxiliary equipment (not shown). The auxiliary equipment operates the module 100. The outer case 111 accommodates the module 100 and the auxiliary equipment. Note that some components are omitted in Fig. 7.

[0092] An exterior case 111 of a module accommodating device 110 shown in Figure 7 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. The space below the partition plate 114 in the exterior case 111 is an accessory accommodating chamber 116 that accommodates accessories configured to operate the module 100. Note that in Figure 7, the accessories accommodated in the accessory accommodating chamber 116 are omitted from the illustration.

[0093] The partition plate 114 also 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 that constitutes the module housing chamber 115 has an exhaust port 118 for exhausting air from within the module housing chamber 115.

[0094] In such a module accommodating device 110, as described above, highly durable modules 100 are provided in the module accommodating chamber 115, so that the module accommodating device 110 can be made highly durable.

[0095] Second Embodiment Fig. 8 is a perspective view showing an example of an electrochemical cell according to a second embodiment, and Fig. 9 is a partial cross-sectional view of the electrochemical cell shown in Fig. 8.

[0096] 8 and 9 , cell 1B includes an element section 3B in which an anode 5, a solid electrolyte layer 6, and an air electrode 8 are stacked, and conductive members 92 and 93. The element section 3B may include a diffusion suppression layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. In an electrochemical cell device in which a plurality of flat-type cells are stacked, for example, the plurality of cells 1B are electrically connected by conductive members 92 and 93, which are adjacent metal bodies. The conductive members 92 and 93 electrically connect adjacent cells 1B and have gas flow paths for supplying gas to the anode 5 or the air electrode 8.

[0097] As shown in Fig. 9, cell 1B has a sealing material that airtightly seals the fuel gas flow path and the oxygen-containing gas flow path of the flat cell stack. The sealing material is a fixing member for the cell and has a sealing portion 9 and support members 94 and 95 that serve as frames. The sealing portion 9 includes a sealing material 90. The sealing material 90 may be, for example, glass such as crystallized glass or amorphous glass, or a brazing material.

[0098] The support member 94 may be a so-called separator that separates the fuel gas flow path from the oxygen-containing gas flow path. The material of the support members 94, 95 may be, for example, a conductive metal or an insulating ceramic. Either of the support members 94, 95 may be an insulating material. If the support member 94 is a metal, the support member 94 may be integrated with the conductive member 93. In this case, the sealing material 90 is an insulating glass material, and the support member 95 is an insulating material. If the support member 95 is a metal, the support member 95 may be integrated with the conductive member 92. In this case, the sealing material 90 may be a glass material or a brazing material, and the support member 94 is an insulating material.

[0099] One of the support members 94 and 95 is insulating, and electrically insulates the two conductive members 92 and 93 that sandwich the flat cell from each other.

[0100] 10 is an enlarged cross-sectional view of region R1 shown in FIG. 9 . As shown in FIG. 10 , the anode 5 may have a first region 51 located at the boundary with the sealing portion 9 and including a first porous portion. The first region 51 may include both the first material m1 contained in the anode 5 and the sealing material 90 contained in the sealing portion 9. This reduces the likelihood of cracking in the sealing portion 9 and / or peeling of the sealing portion 9 from the anode 5 due to a difference in thermal expansion between the anode 5 and the sealing portion 9. Therefore, the cell 1B according to this embodiment has improved durability.

[0101] [Other Embodiments] In the above-described embodiments, a fuel cell, a fuel cell stack device, a fuel cell module, and a fuel cell device are shown as examples of an "electrochemical cell," "electrochemical cell device," "module," and "module housing device." However, other examples may be an electrolysis cell, an electrolysis cell stack device, an electrolysis module, and an electrolysis device, respectively. An electrolysis cell has a first electrode and a second electrode, and decomposes water vapor into hydrogen and oxygen, or decomposes carbon dioxide into carbon monoxide and oxygen, when supplied with electric power. Furthermore, in the above-described embodiments, an oxide ion conductor or a hydrogen ion conductor is shown as an example of the electrolyte material of the electrochemical cell, but a hydroxide ion conductor may also be used. Such electrolysis cells, electrolysis cell stack devices, electrolysis modules, and electrolysis devices can improve electrolysis performance and durability. Solid oxide fuel cells and electrolysis cells are collectively referred to as solid oxide electrochemical cells.

[0102] 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 within the scope that does not deviate from the gist of the present disclosure.

[0103] In one embodiment, (1) an electrochemical cell comprises: an element portion including a metal body, a solid electrolyte layer, and a first electrode including a first material; and a sealing portion including a sealing material and contacting the first electrode and the metal body around the element portion; wherein the first electrode is located at the boundary with the sealing portion and has a first portion including the first material and the sealing material, and the first portion includes a first porous portion.

[0104] (2) In the electrochemical cell of (1) above, the first material may include a plurality of first metal particles and a plurality of first inorganic oxide particles.

[0105] (3) In the electrochemical cell of (1) or (2) above, the first portion may further include a first region that is a first porous portion, and a second region that is located between the first region and the plugging portion, is in contact with the plugging portion, and has a smaller porosity than the first region.

[0106] (4) In the electrochemical cell of any one of (1) to (3) above, the sealing portion may have a second porous portion located at a boundary portion in contact with the first electrode.

[0107] (5) In the electrochemical cell of any one of (1) to (4) above, the sealing portion may further contain the first material.

[0108] (6) In the electrochemical cell of any one of (1) to (5) above, the first electrode is located between the solid electrolyte layer and the plate-shaped metal body, and the electrochemical cell further includes an intermediate layer located between the first electrode and the metal substrate and containing a second material, the intermediate layer being located at a boundary portion in contact with the sealing portion and having a second portion containing the second material and the sealing material, and the second portion may include a third porous portion.

[0109] In one embodiment, (7) an electrochemical cell comprises: a metal plate; an element portion; an intermediate layer located between the metal plate and the element portion and including a second material; and a sealing portion located around the element portion and including a sealing material, wherein the intermediate layer is located at a boundary portion in contact with the sealing portion and has a second portion including the second material and the sealing material, and the second portion includes a third porous portion.

[0110] (8) In the electrochemical cell of (6) or (7) above, the second material may include a plurality of second metal particles and a plurality of second inorganic oxide particles.

[0111] In one embodiment, (9) an electrochemical cell device has a cell stack including any one of the electrochemical cells (1) to (8) above.

[0112] In one embodiment, a module (10) includes the electrochemical cell device (9) described above, and a container for housing the electrochemical cell device.

[0113] In one embodiment, (11) a module housing device includes the module of (10) above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0114] The disclosed embodiments should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0115] REFERENCE SIGNS LIST 1 cell 3 element portion 4 intermediate layer 5 fuel electrode 6 solid electrolyte layer 8 air electrode 9 sealing portion 10 cell stack device 32 metal substrate 41 second portion 51 first portion 100 module 110 module housing device

Claims

1. An electrochemical cell comprising: an element portion including a metal body, a solid electrolyte layer, and a first electrode including a first material; and a sealing portion including a sealing material and contacting the first electrode and the metal body around the periphery of the element portion, wherein the first electrode is located at the boundary with the sealing portion and has a first portion including the first material and the sealing material, and the first portion includes a first porous portion.

2. The electrochemical cell of claim 1, wherein the first material comprises a plurality of first metal particles and a plurality of first inorganic oxide particles.

3. An electrochemical cell as described in claim 1 or 2, wherein the first portion further comprises a first region which is a first porous portion, and a second region which is located between the first region and the sealing portion, contacts the sealing portion, and has a smaller porosity than the first region.

4. An electrochemical cell according to any one of claims 1 to 3, wherein the sealing portion has a second porous portion located at the boundary portion in contact with the first electrode.

5. The electrochemical cell according to any one of claims 1 to 4, wherein the sealing portion further contains the first material.

6. An electrochemical cell according to any one of claims 1 to 5, wherein the first electrode is located between the solid electrolyte layer and the plate-like metal body, and further comprising an intermediate layer located between the first electrode and the metal body and containing a second material, the intermediate layer being located at the boundary contacting the sealing portion and having a second portion containing the second material and the sealing material, the second portion including a third porous portion.

7. An electrochemical cell comprising: a metal plate; an element portion; an intermediate layer located between the metal plate and the element portion and containing a second material; and a sealing portion located around the element portion and containing a sealing material, wherein the intermediate layer is located at a boundary portion in contact with the sealing portion and has a second portion containing the second material and the sealing material, and the second portion includes a third porous portion.

8. The electrochemical cell according to claim 6 or 7, wherein the second material comprises a plurality of second metal particles and a plurality of second inorganic oxide particles.

9. An electrochemical cell device having a cell stack including the electrochemical cell according to any one of claims 1 to 8.

10. A module comprising the electrochemical cell device according to claim 9 and a container that houses the electrochemical cell device.

11. A module housing device comprising: a module according to claim 10; an accessory configured to operate said module; and an outer case housing said module and said accessory.

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