Metal assemblies, electrochemical cells, electrochemical cell devices, modules, and module housings

Abstract

The present invention provides metal assemblies, electrochemical cells, electrochemical cell devices, modules, and module housings that can improve performance. [Solution] The metal joint comprises a first metal plate and a second metal plate. The first metal plate has a first surface and a second surface opposite to the first surface. The second metal plate has a third surface facing the first surface and a fourth surface opposite to the third surface. The first surface has a first contact surface located at the first end, including the first end in the first direction, and extending in a second direction intersecting the first direction. The third surface has a second contact surface located at the first end and extending in a second direction. The metal joint has a weld at the first end where the first metal plate and the second metal plate are welded together. The weld has a first weld surface that is continuously connected to the second surface in the second direction.

Description

[Technical Field]

[0001] This disclosure relates to metal assemblies, electrochemical cells, electrochemical cell devices, modules, and module housing devices. [Background technology]

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

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-39569 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, in conventional fuel cell cell stack devices, there was room for improvement in the performance of metal joints formed by welding adjacent metal components together.

[0005] One embodiment aims to provide a metal assembly, an electrochemical cell, an electrochemical cell apparatus, a module, and a module housing apparatus that can improve performance. [Means for solving the problem]

[0006] A metal joint according to one embodiment comprises a first metal plate and a second metal plate. The first metal plate has a first surface and a second surface opposite to the first surface. The second metal plate has a third surface facing the first surface and a fourth surface opposite to the third surface. The first surface has a first contact surface located at the first end including the first end in the first direction and extending in a second direction intersecting the first direction. The third surface has a second contact surface located at the first end and extending in the second direction. The metal joint has a weld at the first end where the first metal plate and the second metal plate are welded together. The weld has a first weld surface that is continuously connected to the second surface in the second direction.

[0007] Furthermore, the electrochemical cell of this disclosure comprises the metal assembly described above and an element portion. The second metal plate is a metal support having a gas permeable portion between the third surface and the fourth surface that allows gas to pass through. The element portion is located on the fourth surface of the gas permeable portion and has a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer.

[0008] Furthermore, the electrochemical cell of this disclosure comprises the metal assembly described above and an element portion. The first metal plate is a metal support having a gas permeable portion between the first surface and the second surface that allows gas to pass through. The element portion is located on the second surface of the gas permeable portion and has a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer.

[0009] Furthermore, the electrochemical cell apparatus of this disclosure has a cell stack comprising the electrochemical cells described above.

[0010] Furthermore, the module of this disclosure comprises the electrochemical cell apparatus described above and a housing container for housing the electrochemical cell apparatus.

[0011] Furthermore, the module housing device of this disclosure comprises the module described above, auxiliary equipment for operating the module, and an outer case for housing the module and the auxiliary equipment. [Effects of the Invention]

[0012] According to one aspect of the embodiment, a metal joint, an electrochemical cell, an electrochemical cell device, a module, and a module housing device capable of improving performance can be provided.

Brief Description of the Drawings

[0013] [Figure 1] FIG. 1 is a plan view showing an example of an electrochemical cell device according to the first embodiment. [Figure 2A] FIG. 2A is a cross-sectional view showing an example of an electrochemical cell device according to the first embodiment. [Figure 2B] FIG. 2B is a cross-sectional view showing another example of an electrochemical cell device according to the first embodiment. [Figure 3A] FIG. 3A is a cross-sectional view showing an example of a metal joint according to the first embodiment. [Figure 3B] FIG. 3B is a cross-sectional view showing another example of a metal joint according to the first embodiment. [Figure 3C] FIG. 3C is a cross-sectional view showing another example of a metal joint according to the first embodiment. [Figure 3D] FIG. 3D is a cross-sectional view showing another example of a metal joint according to the first embodiment. [Figure 4] FIG. 4 is a side view showing an example of a metal joint according to the first embodiment. [Figure 5] FIG. 5 is a plan view showing an example of an electrochemical cell device according to the second embodiment. [Figure 6A] FIG. 6A is a cross-sectional view showing an example of a metal joint according to the second embodiment. [Figure 6B] FIG. 6B is a cross-sectional view showing another example of a metal joint according to the second embodiment. [Figure 6C] FIG. 6C is a cross-sectional view showing another example of a metal joint according to the second embodiment. [Figure 6D] FIG. 6D is a cross-sectional view showing another example of a metal joint according to the second embodiment. [Figure 7] FIG. 7 is a side view showing an example of a metal joint according to the second embodiment. [Figure 8A] Figure 8A is a perspective view showing an example of an electrochemical cell apparatus according to the embodiment. [Figure 8B] Figure 8B is a cross-sectional view of the XX line shown in Figure 8A. [Figure 8C] Figure 8C is a top view showing an example of an electrochemical cell apparatus according to the embodiment. [Figure 9] Figure 9 is an external perspective view showing an example of a module according to the embodiment. [Figure 10] Figure 10 is a schematic exploded perspective view showing an example of a module housing device according to an embodiment. [Modes for carrying out the invention]

[0014] Hereinafter, embodiments of the metal assemblies, electrochemical cells, electrochemical cell apparatuses, modules, and module housings disclosed in this application will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments described below.

[0015] Furthermore, it should be noted that drawings are schematic representations, and the dimensional relationships and proportions of each element may differ from reality. Moreover, there may be discrepancies in dimensional relationships and proportions between drawings themselves.

[0016] [First Embodiment] <Configuration of an electrochemical cell> First, with reference to Figures 1 and 2A, an example of a solid oxide fuel cell will be described as an electrochemical cell comprising a metal assembly according to the first embodiment. 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 simply be referred to as a cell stack device.

[0017] Figure 1 is a plan view showing an example of an electrochemical cell apparatus according to the first embodiment. Figure 2A is a cross-sectional view showing an example of an electrochemical cell apparatus according to the first embodiment. Figure 2A corresponds to the cross-sectional view of line AA shown in Figure 1. Note that in Figures 1 and 2A, some parts of the components of the electrochemical cell are shown in enlargement. Hereafter, the electrochemical cell may simply be referred to as a cell.

[0018] For the sake of clarity, Figures 1 and 2A illustrate a three-dimensional Cartesian coordinate system including a Z-axis, where the vertically upward direction is positive and the vertically downward direction is negative. This Cartesian coordinate system may also be shown in other diagrams used in the explanations below. Furthermore, components with the same reference numerals as those in the electrochemical cell shown in Figures 1 and 2A are used, and their explanations are omitted or simplified.

[0019] The cell stack device 10 according to this embodiment comprises a cell 1 and a metal assembly 50. The cell 1 comprises an element section 3.

[0020] The element 3 comprises a fuel electrode 5, a solid electrolyte layer 6, and an air electrode 8. The fuel electrode 5 is a second electrode in contact with the fuel gas, which is a reducing gas. The fuel electrode 5 contains metal particles. The fuel electrode 5 is gas permeable. The open porosity of the fuel electrode 5 may be in the range of, for example, 30% to 50%, particularly 35% to 45%. The open porosity of the fuel electrode 5 is sometimes referred to as the porosity or void ratio of the fuel electrode 5.

[0021] The fuel electrode 5 can be made from materials that are generally known. The fuel electrode 5 may be made from porous conductive ceramics, such as ceramics containing calcium oxide, magnesium oxide, or ZrO2 in which rare earth element oxides are in solid solution, and Ni and / or NiO. These rare earth element oxides may include multiple rare earth elements selected from, for example, Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. The ZrO2 in which calcium oxide, magnesium oxide, or rare earth element oxides are in solid solution is sometimes referred to as stabilized zirconia. The stabilized zirconia may include partially stabilized zirconia. The fuel electrode 5 may also contain CeO2 in which La, Nd, or Yb are in solid solution.

[0022] The solid electrolyte layer 6 is an electrolyte that facilitates the transfer of ions between the fuel electrode 5 and the air electrode 8. At the same time, the solid electrolyte layer 6 has gas barrier properties, making it difficult for leaks between the fuel gas and the oxygen-containing gas to occur.

[0023] The material of the solid electrolyte layer 6 may be, for example, ZrO2 in which 3 mol% to 15 mol% of rare earth element oxides are dissolved. The rare earth element oxides may include, 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 contain, for example, ZrO2 in which Yb, Sc, or Gd are dissolved, CeO2 in which La, Nd, or Yb are dissolved, BaZrO3 in which Sc or Yb are dissolved, or BaCeO3 in which Sc or Yb are dissolved.

[0024] The air electrode 8 is the first electrode in contact with the oxygen-containing gas. The air electrode 8 is gas permeable. The open porosity of the air electrode 8 may be in the range of, for example, 20% to 50%, and especially 30% to 50%. The open porosity of the air electrode 8 is sometimes referred to as the void ratio of the air electrode 8.

[0025] The material for the air electrode 8 is not particularly limited as long as it is a material commonly used for air electrodes. For example, the material for the air electrode 8 may be conductive ceramics such as so-called ABO3 type perovskite oxides.

[0026] 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 O3, La x Sr 1-x MnO3, La x Sr 1-x FeO3, La x Sr 1-x CoO3, etc. Here, x is 0 < x < 1 and y is 0 < y < 1.

[0027] In addition, the element part 3 may have an intermediate layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. When the element part 3 has an intermediate layer, the intermediate layer has, for example, a function as a diffusion suppression layer. When a specific element such as Sr (strontium) contained in the air electrode 8 diffuses into the solid electrolyte layer 6, a resistance layer such as SrZrO3 is formed in the solid electrolyte layer 6. The intermediate layer makes it difficult for elements such as Sr to diffuse, thereby making it difficult for a high-resistance compound such as SrZrO3 to be formed.

[0028] The material of the intermediate layer is not particularly limited as long as it generally makes it difficult for elements to diffuse between the air electrode 8 and the solid electrolyte layer 6. The material of the intermediate layer may include, for example, cerium oxide (CeO2) in which rare earth elements excluding Ce (cerium) are solid-dissolved. As such rare earth elements, for example, Gd (gadolinium), Sm (samarium), etc. may be used.

[0029] In addition, the cell 1 may further have a restraint layer (not shown). The restraint layer may be located between the fuel electrode 5 and the metal joining body 50. Such a restraint layer cooperates with the solid electrolyte layer 6 to make it difficult for the element part 3 to warp or bend.

[0030] The material of the constraining layer exhibits a shrinkage rate similar to that 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 3 obtained by sandwiching the material of the fuel electrode 5 of the element 3 between the material of the solid electrolyte layer 6 and the material of the constraining layer and firing it will have less warping or deformation.

[0031] The restraining layer may or may not be gas permeable. If the restraining layer has gas barrier properties similar to those of the solid electrolyte layer 6, the restraining layer can be partially positioned so as not to obstruct the inflow of fuel gas to the fuel electrode 5.

[0032] Furthermore, cell 1 may have a gas diffusion layer (not shown). The gas diffusion layer may be located between the fuel electrode 5 and the metal assembly 50. Such a gas diffusion layer is gas permeable and allows the fuel gas flowing through the channel 30a (described later) to permeate to the fuel electrode 5. The open porosity of the gas diffusion layer may be, for example, in the range of 30% to 50%, particularly 35% to 45%.

[0033] The material for the gas diffusion layer may be a porous conductive ceramic, such as a ceramic containing calcium oxide, magnesium oxide, or stabilized or partially stabilized zirconia in which a rare earth element oxide is in solid solution, and Ni and / or NiO. This rare earth element oxide may contain, for example, multiple rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb.

[0034] Cell 1 may also have an adhesive (not shown). The adhesive may be located between the fuel electrode 5 and the metal assembly 50. Such adhesive joins the element portion 3 and the metal assembly 50, fixing the element portion 3 to the metal assembly 50.

[0035] The adhesive may be conductive. The adhesive may contain, for example, conductive particles such as Ni and inorganic oxides such as TiO2, rare earth element oxides (Y2O3, CeO2, etc.), and transition metal oxides (Fe2O3, CuO, etc.).

[0036] The adhesive may be gas permeable. Furthermore, the solid electrolyte layer 6 may be positioned to cover the sides of the adhesive.

[0037] The metal assembly 50 is located between the first element section 3A and the second element section 3B, which is located next to the first element section 3A. The metal assembly 50 is located between the air electrode 8 of the first element section 3A and the fuel electrode 5 of the second element section 3B. The metal assembly 50 comprises a first metal plate 30 and a second metal plate 40.

[0038] The first metal plate 30 has a surface 31 and a surface 32 opposite to surface 31. Surface 31 is located opposite the second metal plate 40. Surface 32 is located opposite the air electrode 8 of the first element portion 3A.

[0039] A passage 30a through which fuel gas flows is located between the surface 31 of the first metal plate 30 and the second metal plate 40. The fuel gas flowing through the passage 30a is supplied to the fuel electrode 5 by passing through the second metal plate 40.

[0040] Surface 32 is fixed to the air electrode 8, for example, via a conductive adhesive, and electrically joined. A space through which an oxygen-containing gas flows is located between the first metal plate 30 and the air electrode 8.

[0041] The first metal plate 30 has end faces 33 and 34 located at both ends in the X-axis direction. The surface 32 of the first metal plate 30 may have a first portion 321 and a second portion 322, as shown in Figure 1.

[0042] The first portion 321 is located in the central part in the X-axis direction, facing the air pole 8. The first metal plate 30 may have a first protrusion 30b and a flow channel portion 30d on the first portion 321.

[0043] The first protrusion 30b is positioned to protrude from the flow channel 30d toward the positive Y-axis direction. The surface of the first protrusion 30b may be in contact with the air electrode 8.

[0044] The flow path section 30d is located between the first metal plate 30 and the air electrode 8 of the element section 3, and is a space through which oxygen-containing gas flows. The flow path section 30d may have, for example, a flat surface 32.

[0045] The first metal plate 30 may have a second protrusion 30c on the surface 31 located opposite the first portion 321. The second protrusion 30c is positioned to project from the surface 31 toward the negative Y-axis direction. The second protrusion 30c may be in contact with the second metal plate 40. The surface 32 may have a recess corresponding to the shape of the second protrusion 30c.

[0046] The second portion 322 is located at both ends in the X-axis direction adjacent to the first portion 321. The second portion 322 has an end 322a including an end face 33 which is the first end in the first direction (X-axis direction), and an end 322b including an end face 34 which is the second end in the first direction.

[0047] The first metal plate 30 has end faces 35 and 36 located at both ends in the Z-axis direction. The oxygen-containing gas may flow through the flow channel 30d, which is the space between the surface 32 located on the first portion 321 and the air electrode 8, for example, from the end face 35 side to the end face 36 side.

[0048] The second metal plate 40 has a surface 41 and a surface 42 opposite to surface 41. Surface 41 is positioned to face surface 31 of the first metal plate 30. Surface 42 is positioned to face the second element portion 3B.

[0049] The second metal plate 40 has a gas permeable portion 401 facing the flow path 30a. The gas permeable portion 401 is gas permeable. The gas permeable portion 401 is configured to allow gas to pass through between surface 41 and surface 42. The second metal plate 40 may have a hole 40a that penetrates in the thickness direction (Y-axis direction). The hole 40a may allow fuel gas flowing through the flow path 30a to pass through. The element portion 3 is located on surface 42 of the gas permeable portion 401. The fuel gas that has passed through the hole 40a is supplied to the fuel electrode 5. The diameter of the hole 40a may be, for example, 0.1 mm to 0.5 mm, particularly 0.3 mm to 0.4 mm. The opening ratio in the gas permeable portion 401 in which the hole 40a is formed may be, for example, 10% or more. The second metal plate 40 may have a coating that covers the wall surface of the hole 40a. The second metal plate 40 does not need to have a coating on the wall surface of the hole 40a.

[0050] The first metal plate 30 and the second metal plate 40 are electrically conductive. The first metal plate 30 and the second metal plate 40 may also be composed of, for example, a plate-shaped metal containing chromium. The first metal plate 30 and the second metal plate 40 may be, for example, stainless steel such as ferritic stainless steel or austenitic stainless steel, which have high heat resistance. The first metal plate 30 and the second metal plate 40 may also be, for example, a nickel-chromium alloy or an iron-chromium alloy. The first metal plate 30 and / or the second metal plate 40 may have a coating covering their surface. The first metal plate 30 and / or the second metal plate 40 do not need to have a coating on their surface. The materials of the first metal plate 30 and the second metal plate 40 may be the same or different.

[0051] The metal joint 50 has a welded portion 60 extending along the Z-axis direction in the second portion 322. The welded portion 60 electrically connects the first metal plate 30 and the second metal plate 40. Details of the welded portion 60 will be described later.

[0052] Figure 2B is a cross-sectional view showing another example of an electrochemical cell apparatus according to the first embodiment. As shown in Figure 2B, a sealant 9 different from the solid electrolyte layer 6 may be located on the sides of the fuel electrode 5 and the solid electrolyte layer 6. The sealant 9 may be dense glass or ceramic. The material of the sealant 9 may be, for example, amorphous glass or crystallized glass. As for the crystallized glass, any of the following materials may be used, for example, SiO2-CaO system, MgO-B2O3 system, La2O3-B2O3-MgO system, La2O3-B2O3-ZnO system, SiO2-CaO-ZnO system, and in particular, SiO2-MgO system material may be used. The sealant 9 may have electrical insulating properties.

[0053] <Details of the metal joint> Next, the details of the metal joint 50 according to this embodiment will be further described with reference to Figures 1, 2A, and 3A to 4. Figure 3A is a cross-sectional view showing an example of the metal joint according to the first embodiment. Figure 3A corresponds to the cross-sectional view of line BB shown in Figure 1.

[0054] The metal joint 50 comprises a first metal plate 30 and a second metal plate 40. The first metal plate 30 has a surface 31 as a first surface and a surface 32 as a second surface. The second metal plate 40 has a surface 41 as a third surface and a surface 42 as a fourth surface.

[0055] As shown in Figure 3A, the surface 31 of the first metal plate 30 has a contact surface 312a extending in the Z-axis direction as the second direction. The contact surface 312a is a contact surface 312 located at the first end 50a of the metal joint 50, which includes the end face 33. The contact surface 312a may be positioned to overlap with the end 322a in a plan view.

[0056] The surface 41 of the second metal plate 40 has a contact surface 412 extending in the Z-axis direction. The contact surface 412 is located at the first end 50a of the metal joint 50, which includes the end face 43.

[0057] The metal joint 50 has a welded joint 60a at its first end 50a, where the first metal plate 30 and the second metal plate 40 are welded together. The welded joint 60a has a first welded surface 61 that is continuously connected in the Z-axis direction to the end 322a of the surface 32.

[0058] For example, if oxygen-containing gas enters the small gap that inevitably forms between the contact surface 312 and the contact surface 412, crevice corrosion may occur due to differences in oxygen concentration, potentially degrading the performance of the metal joint 50. According to the metal joint 50 of this embodiment, the welded portion 60a has a first welded surface 61 that is continuously connected in the Z-axis direction, making it easier for the joint between the contact surface 312 and the contact surface 412 to be continuous in the Z-axis direction. As a result, oxygen-containing gas is less likely to enter the gap between the contact surface 312 and the contact surface 412 that is connected to the flow path 30a, and crevice corrosion between the contact surface 312 and the contact surface 412 is less likely to occur. Therefore, the performance of the metal joint 50 is improved.

[0059] As shown in Figure 3A, the first welding surface 61 of the welded joint 60 has a first width W0 in the X-axis direction. In the first welding surface 61 of the welded joint 60 extending in the Z-axis direction, the maximum value of the first width W0 is W max Let the minimum value be W min When that happens, W min is W max It may be 0.5 times or more. This further reduces the likelihood of crevice corrosion between the contact surface 312 and the contact surface 412, and further improves the performance of the metal joint 50. The thicknesses of the first metal plate 30 and the second metal plate 40 may be, for example, 0.2 mm or more and 0.5 mm or less. The thicknesses of the first metal plate 30 and the second metal plate may be the same or different. The first metal plate 30 may have a smaller thickness than the second metal plate 40. When the thickness of the first metal plate 30 is t1, W min It may be 0.2 times or more of t1.

[0060] Figures 3B to 3D are cross-sectional views showing another example of a metal joint according to the first embodiment. Figures 3B to 3D correspond to the cross-sectional view of line BB shown in Figure 1.

[0061] As shown in Figure 3B, the welded joint 60 may further have a second welded surface 62 on the surface 42 as the fourth surface. This makes the joint between the first metal plate 30 and the second metal plate 40 more continuous in the Z direction, further reducing the likelihood of crevice corrosion between the contact surfaces 312 and 412, and further improving the performance of the metal joint 50.

[0062] Furthermore, the first welding surface 61 of the welded joint 60 has a first width W1 in the X-axis direction, and the second welding surface 62 has a second width W2 in the X-axis direction. In this case, the average of the first width W1 may be greater than the average of the second width W2. This makes it easier for the joint between the first metal plate 30 and the second metal plate 40 to be more continuous in the Z-direction, which reduces the likelihood of crevice corrosion between the contact surfaces 312 and 412, and improves the performance of the metal joint 50.

[0063] Furthermore, as shown in Figure 3C, the welded joint 60 may have a third welded surface 63 at the first end 50a, located between the second surface 32 and the fourth surface 42. This further reduces crevice corrosion between the contact surfaces 312 and 412, thereby further improving the performance of the metal joint 50. The third welded surface 63 may also be located on the end surface 33 and / or the end surface 43.

[0064] Furthermore, as shown in Figure 3D, the welded joint 60 may have a portion where the first welded surface 61 and the third welded surface 63 are continuous, straddling the corner 39 located between the surface 32 and the end surface 33. In other words, at least a portion of the third welded surface 63 may be connected to the first welded surface 61. This further reduces the likelihood of crevice corrosion between the contact surfaces 312 and 412, and further improves the performance of the metal joint 50.

[0065] Figure 4 is a side view showing an example of a metal joint according to the first embodiment. Figure 4 shows a case in the first embodiment having the cross-section shown in Figure 3D. As shown in Figure 4, the metal joint 50 may have one or more openings 70 on the end face 33 located between the first contact surface 312 and the second contact surface 412, and at the first end 50a. In this case, when the length of the end face 33 in the Z-axis direction is L0 and the sum of the lengths of the openings 70 in the Z-axis direction is L1, L1 may be 80% or less of L0. This further reduces the likelihood of crevice corrosion between the contact surfaces 312 and 412, and further improves the performance of the metal joint 50. The width of the opening 70 along the Y-axis direction may be, for example, 200 μm or less. In the example shown in Figure 4, the sum of the lengths of the three openings 70, L11 + L12 + L13, can be taken as L1.

[0066] Such a metal joint 50 can be manufactured by overlapping the contact surfaces 312 of the first metal plate 30 and the contact surfaces 412 of the second metal plate 40 so that they face each other, and then using a fusion welding method such as irradiating the surface 32 with laser light, an electron beam, plasma, etc., or a friction welding method.

[0067] [Second Embodiment] Figure 5 is a plan view showing an example of an electrochemical cell apparatus according to the second embodiment. Figure 6A is a cross-sectional view showing an example of a metal assembly according to the second embodiment. Figure 6A corresponds to the cross-sectional view of line CC shown in Figure 5.

[0068] The metal joint 50 comprises a second metal plate 40 and a first metal plate 30. The second metal plate 40 has a surface 41 as a first surface and a surface 42 as a second surface. The first metal plate 30 has a surface 31 as a third surface and a surface 32 as a fourth surface.

[0069] The second metal plate 40 has end faces 43 and 44 located at both ends in the X-axis direction. The surface 42 of the second metal plate 40 may have a first portion 421 and a second portion 422, as shown in Figure 5.

[0070] The first portion 421 is located in the central part in the X-axis direction, facing the fuel electrode 5. The second metal plate 40 may have a gas permeable portion 401 in the first portion 421.

[0071] The second portion 422 is located at both ends in the X-axis direction adjacent to the first portion 421. The second portion 422 has an end 422a including an end face 43 which is the first end in the first direction (X-axis direction), and an end 422b including an end face 44 which is the second end in the first direction.

[0072] The second metal plate 40 has end faces 45 and 46 located at both ends in the Z-axis direction. The fuel gas may flow through the flow path 30a, which is the space between the surface 41 of the second metal plate 40 and the first metal plate 30, for example, from the end face 45 side to the end face 46 side.

[0073] As shown in Figure 6A, the surface 41 of the second metal plate 40 has a contact surface 412a extending in the Z-axis direction as the second direction. The contact surface 412a is a contact surface 412 located at the first end 50a of the metal joint 50, which includes the end face 43.

[0074] The surface 31 of the first metal plate 30 has a contact surface 312 extending in the Z-axis direction. The contact surface 312 is located at the first end 50a of the metal joint 50, which includes the end face 33.

[0075] The metal joint 50 has a welded portion 60a at its first end 50a, where the second metal plate 40 and the first metal plate 30 are welded together. The welded portion 60a has a first welded surface 66 that is continuously connected in the Z-axis direction to the end 422a of the surface 42.

[0076] Thus, by having a first welding surface 66 that is continuously connected in the Z-axis direction to the welded portion 60a, the joining of the contact surface 412 and the contact surface 312 becomes more continuous in the Z-axis direction. As a result, oxygen-containing gas is less likely to enter the gap between the contact surface 412 and the contact surface 312 that is connected to the flow path 30a, and crevice corrosion between the contact surface 412 and the contact surface 312 is less likely to occur. Therefore, the performance of the metal joint 50 is improved.

[0077] As shown in Figure 6A, the first welding surface 66 of the welded joint 60 has a first width W10 in the X-axis direction. In the first welding surface 66 of the welded joint 60 extending in the Z-axis direction, the maximum value of the first width W10 is W max Let the minimum value be W min When that happens, W min is W max It may be 0.5 times or more. This further reduces the likelihood of crevice corrosion between the contact surface 412 and the contact surface 312, and further improves the performance of the metal joint 50. The thicknesses of the first metal plate 30 and the second metal plate 40 may be, for example, 0.2 mm or more and 0.5 mm or less. The thicknesses of the first metal plate 30 and the second metal plate may be the same or different. The second metal plate 40 may have a smaller thickness than the first metal plate 30. When the thickness of the second metal plate 40 is t2, W min It may be 0.2 times or more of t2.

[0078] Figures 6B to 6D are cross-sectional views showing another example of a metal joint according to the second embodiment. Figures 6B to 6D correspond to the cross-sectional view along line CC shown in Figure 5.

[0079] As shown in Figure 6B, the welded joint 60 may further have a second welded surface 67 on the surface 32 as the fourth surface. This makes the joint between the second metal plate 40 and the first metal plate 30 more continuous in the Z direction, further reducing the likelihood of crevice corrosion between the contact surfaces 412 and 312, and further improving the performance of the metal joint 50.

[0080] Furthermore, the first welding surface 66 of the welded joint 60 has a first width W11 in the X-axis direction, and the second welding surface 67 has a second width W12 in the X-axis direction. In this case, the average of the first width W11 may be greater than the average of the second width W12. This makes it easier for the joint between the second metal plate 40 and the first metal plate 30 to be more continuous in the Z-direction, which reduces the likelihood of crevice corrosion between the contact surfaces 412 and 312, and improves the performance of the metal joint 50.

[0081] Furthermore, as shown in Figure 6C, the welded joint 60 may have a third welding surface 68 at the first end 50a, located between the second surface 42 and the fourth surface 32. This further reduces crevice corrosion between the contact surfaces 412 and 312, thereby further improving the performance of the metal joint 50. The third welding surface 68 may also be located on the end surface 43 and / or the end surface 33.

[0082] Furthermore, as shown in Figure 6D, the welded joint 60 may have a portion where the first welding surface 66 and the third welding surface 68 are continuous, straddling the corner 49 located between the surface 42 and the end surface 43. In other words, at least a portion of the third welding surface 68 may be connected to the first welding surface 66. This further reduces the likelihood of crevice corrosion between the contact surfaces 412 and 312, and further improves the performance of the metal joint 50.

[0083] Figure 7 is a side view showing an example of a metal joint according to the second embodiment. Figure 7 shows a case of the second embodiment having the cross-section shown in Figure 6D. As shown in Figure 7, the metal joint 50 may have one or more openings 70 on the end face 43 located between the first contact surface 412 and the second contact surface 312, and at the first end 50a. In this case, when the length of the end face 43 in the Z-axis direction is L10 and the sum of the lengths of the openings 70 in the Z-axis direction is L11, L11 may be 80% or less of L10. This further reduces the likelihood of crevice corrosion between the contact surface 412 and the contact surface 312, and further improves the performance of the metal joint 50. The width of the opening 70 along the Y-axis direction may be, for example, 200 μm or less. In the example shown in Figure 7, the sum of the lengths of the three openings 70, L111 + L112 + L113, can be taken as L11.

[0084] Such a metal joint 50 can be manufactured by overlapping the contact surfaces 312 of the first metal plate 30 and the contact surfaces 412 of the second metal plate 40 so that they face each other, and then using a fusion welding method such as irradiating the surface 42 with laser light, an electron beam, plasma, etc., or a friction welding method.

[0085] In the embodiments described above, the first end portion 50a of the metal joint 50 was used as an example, but the second end portion 50b shown in Figures 1 and 5 can also be configured as described above. For example, the abutment surface 312 may have an abutment surface 312b located at the second end portion 50b of the metal joint 50, including the end portion 34. The metal joint 50 may have an abutment surface 412a located at the second end portion 50b, including the end portion 44, and facing the abutment surface 312b. Furthermore, the metal joint 50 may have a welded portion 60b at the second end portion 50b where the first metal plate 30 and the second metal plate 40 are welded together. This further reduces the likelihood of crevice corrosion between the abutment surface 312 and the abutment surface 412. As a result, the performance of the metal joint 50 is further improved.

[0086] [Configuration of an electrochemical cell apparatus] Next, an electrochemical cell apparatus using the metal assembly 50 described above will be explained with reference to Figures 8A to 8C. Figure 8A is a perspective view showing an example of an electrochemical cell apparatus according to the embodiment. Figure 8B is a cross-sectional view taken along line XX shown in Figure 8A. Figure 8C is a top view showing an example of an electrochemical cell apparatus according to the embodiment.

[0087] As shown in Figure 8A, the cell stacking device 10 comprises a cell stack 11 having a plurality of cells 1 arranged (stacked) in the thickness direction (Y-axis direction) of the cells 1, and a fixing member 12.

[0088] The fixing member 12 includes 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 includes a support body 15 and a gas tank 16. The support body 15 and the gas tank 16, which make up the support member 14, are made of metal and are electrically conductive.

[0089] As shown in Figure 8B, the support 15 has an insertion hole 15a into which the lower ends of the multiple cells 1 are inserted. The lower ends of the multiple cells 1 and the inner wall of the insertion hole 15a are joined together by a fixing member 13.

[0090] The gas tank 16 has an opening that supplies reaction gas to multiple cells 1 through an insertion hole 15a, and a groove 16a located around the opening. The outer end of the support 15 is joined to the gas tank 16 by a bonding material 21 that is filled into the groove 16a of the gas tank 16.

[0091] In the example shown in Figure 8A, fuel gas is stored in the internal space 22 (see Figure 8B) formed by the support member 14, which is the support body 15, and the gas tank 16. A gas flow pipe 20 is connected to the gas tank 16. Fuel gas is supplied to the gas tank 16 through this gas flow pipe 20 and then supplied from the gas tank 16 to the flow path 30a (see Figure 2A) inside the cell 1. The fuel gas supplied to the gas tank 16 is generated in the reformer 104 (see Figure 9), which will be described later.

[0092] Hydrogen-rich fuel gas can be produced by steam reforming of the raw fuel. When fuel gas is produced by steam reforming, the fuel gas contains water vapor.

[0093] The example shown in Figure 8A includes two rows of cell stacks 11, two support members 15, and a gas tank 16. Each of the two rows of cell stacks 11 has multiple cells 1. Each cell stack 11 is fixed to each support member 15. The gas tank 16 has two through holes on its top surface. Each support member 15 is placed in each through hole. The internal space 22 is formed by one gas tank 16 and two support members 15. The cell stack device 10 may have only one cell stack 11, or it may have three or more cell stacks 11.

[0094] The shape of the insertion hole 15a is, for example, oval when viewed from above. The length of the insertion hole 15a in the direction of cell arrangement 1, i.e., the thickness direction (Y-axis direction: see Figure 2A), is greater than the distance between the two end current collector 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 cell 1 in the width direction (X-axis direction: see Figure 1).

[0095] As shown in Figure 8B, the joint between the inner wall of the insertion hole 15a and the lower end of the cell 1 is filled with and solidified with fixing material 13. As a result, the inner wall of the insertion hole 15a is joined and fixed to the lower ends of multiple cells 1, and the lower ends of the cells 1 are also joined and fixed to each other. The flow path 2a of each cell 1 communicates with the internal space 22 of the support member 14 at its lower end.

[0096] The fixing material 13 and the bonding material 21 can be made of materials with low conductivity, such as glass. Specific materials for the fixing material 13 and the bonding material 21 may include amorphous glass, and in particular, crystallized glass may be used.

[0097] As the crystallized glass, any of the following materials may be used, for example: SiO2-CaO system, MgO-B2O3 system, La2O3-B2O3-MgO system, La2O3-B2O3-ZnO system, SiO2-CaO-ZnO system, and in particular, SiO2-MgO system materials may be used.

[0098] Furthermore, as shown in Figure 8B, a conductive member 18 is interposed between adjacent cells 1 among the multiple cells 1. The conductive member 18 electrically connects one adjacent cell 1 and the other cell 1 in series. More specifically, the conductive member 18 connects the fuel electrode 5 of one cell 1 and the air electrode 8 of the other cell 1.

[0099] Furthermore, as shown in Figure 8B, the end current collector 17 is electrically connected to the outermost cell 1 in the arrangement direction of the multiple cells 1. The end current collector 17 is connected to a conductive part 19 that protrudes to the outside of the cell stack 11. The conductive part 19 collects the electricity generated by the cell 1 and draws it out to the outside. Note that the end current collector 17 is not shown in Figure 8A.

[0100] Furthermore, as shown in Figure 8C, the cell stack device 10 may be a single battery in which two cell stacks 11A and 11B are connected in series. In this case, the conductive part 19 of the cell stack device 10 may have a positive terminal 19A, a negative terminal 19B, and a connection terminal 19C.

[0101] The positive terminal 19A is the positive terminal when the power generated by the cell stack 11 is output to the outside. The positive terminal 19A is electrically connected to the positive terminal end current collector 17 of the cell stack 11A. The negative terminal 19B is the negative terminal when the power generated by the cell stack 11 is output to the outside. The negative terminal 19B is electrically connected to the negative terminal end current collector 17 of the cell stack 11B.

[0102] The connection terminal 19C electrically connects the negative terminal end current collector 17 of the cell stack 11A to the positive terminal end current collector 17 of the cell stack 11B.

[0103] [Module] Next, a module according to the embodiment of this disclosure using the cell stack device 10 described above will be explained with reference to Figure 9. Figure 9 is an external perspective view showing an example of a module according to the embodiment. Figure 9 shows the 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 housed inside has been taken out to the rear.

[0104] As shown in Figure 9, the module 100 comprises a storage container 101 and a cell stack device 10 housed within the storage container 101. A reformer 102 may also be positioned above the cell stack device 10.

[0105] The reformer 102 reforms raw fuels such as natural gas and kerosene to produce fuel gas, which is then supplied to cell 1. The raw fuels are supplied to the reformer 102 through a raw fuel supply pipe 103. The reformer 102 may also include a vaporization section 102a for vaporizing water and a reforming section 102b. The reforming section 102b is equipped with a reforming catalyst (not shown) and reforms the raw fuels into fuel gas. Such a reformer 102 can perform steam reforming, which is a highly efficient reforming reaction.

[0106] The fuel gas generated in the reformer 102 is then supplied to the flow path 30a of cell 1 (see Figure 2A) through the gas flow pipe 20, the gas tank 16, and the support member 14.

[0107] Furthermore, in the module 100 with the above configuration, the temperature inside the module 100 during normal power generation is approximately 500°C to 1000°C due to the combustion of gas and the power generation of cell 1.

[0108] In such a module 100, as described above, the module 100 can be configured to house a cell stack device 10 with improved performance, thereby improving its performance.

[0109] [Module housing device] Next, a fuel cell device, which is an example of a module housing device according to the embodiment of this disclosure using the module 100 described above, will be explained with reference to Figure 10. Figure 10 is an exploded perspective view schematically showing an example of a module housing device according to this embodiment. The module housing device 110 according to this embodiment comprises an outer case 111, the module 100 shown in Figure 9, 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 Figure 10.

[0110] The outer casing 111 of the module housing device 110 shown in Figure 10 has support columns 112 and outer panels 113. Partition plates 114 divide the inside of the outer casing 111 into upper and lower sections. The space above the partition plates 114 inside the outer casing 111 is the module housing chamber 115 for housing the module 100, and the space below the partition plates 114 inside the outer casing 111 is the auxiliary equipment housing chamber 116 for housing the auxiliary equipment that operates the module 100. Note that in Figure 10, the auxiliary equipment housed in the auxiliary equipment housing chamber 116 is omitted from the illustration.

[0111] Furthermore, the partition plate 114 has an air circulation port 117 for allowing air from the auxiliary equipment storage room 116 to flow towards the module storage room 115. The outer panel 113 that constitutes the module storage room 115 has an exhaust port 118 for exhausting the air inside the module storage room 115.

[0112] In such a module housing device 110, as described above, by providing a module 100 with improved durability in the module housing chamber 115, the module housing device 110 can be made to have improved performance.

[0113] [Other embodiments] In the embodiments described above, a fuel cell cell, fuel cell cell stack, fuel cell module, and fuel cell device were shown as examples of "electrochemical cell," "electrochemical cell device," "module," and "module housing device," but other examples may be an electrolytic cell, electrolytic cell stack, electrolytic module, and electrolytic device, respectively. An electrolytic cell has a hydrogen electrode as a first electrode and an oxygen electrode as a second electrode, and decomposes water vapor into hydrogen and oxygen, or carbon dioxide into carbon monoxide and oxygen, by supplying electricity. In the embodiments described above, an oxide ion conductor or a hydrogen ion conductor was shown as an example of the electrolyte material for the electrochemical cell, but a hydroxide ion conductor may also be used. Such electrolytic cells, electrolytic cell stacks, electrolytic modules, and electrolytic devices can improve performance.

[0114] Although the present disclosure has been described in detail above, this disclosure is not limited to the embodiments described above, and various modifications and improvements are possible without departing from the gist of this disclosure.

[0115] In one embodiment, (1) the metal joint comprises a first metal plate having a first surface and a second surface opposite to the first surface, A second metal plate having a third surface facing the first surface and a fourth surface opposite the third surface. Equipped with, The first surface has a first contact surface located at the first end including the first end in the first direction, and extending in a second direction intersecting the first direction. The third surface is located at the first end and has a second contact surface extending in the second direction, The first end has a welded portion where the first metal plate and the second metal plate are welded together. The welded portion has a first welded surface that is continuously connected to the second surface in the second direction.

[0116] (2) In the metal joint described in (1) above, the first welding surface has a first width in the first direction, The maximum value of the first width is W max Let the minimum value be W min When that happens, W min is W max It may be 0.5 times or more.

[0117] (3) In the metal joint described in (1) or (2) above, the welded portion may further have a second welded surface on the fourth surface.

[0118] (4) In the metal joint described in (3) above, the first welding surface has a first width in the first direction, The second welding surface has a second width in the first direction, The average of the preceding first width may be greater than the average of the preceding second width.

[0119] (5) In any one of the metal joints described in (1) to (4) above, the welded portion may have a third welded surface located between the second surface and the fourth surface at the first end.

[0120] (6) In the metal joint described in (5) above, at least a portion of the third weld surface may be connected to the first weld surface.

[0121] (7) In any one of the metal joints described in (1) to (6) above, the first end face located between the first contact surface and the second contact surface and at the first end has one or more openings, When the length of the first end face in the first direction is L0, and the sum of the lengths of the one or more openings in the first direction is L1, L1 may be 80% or less of L0.

[0122] In one embodiment, (8) the electrochemical cell comprises a metal assembly described in any one of (1) to (7) above, An element portion having a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer Equipped with, The second metal plate is a metal support having a gas permeable portion between the third surface and the fourth surface that allows gas to pass through, The element portion is located on the fourth surface of the gas permeable portion.

[0123] In one embodiment, (9) the electrochemical cell comprises a metal assembly described in any one of (1) to (7) above, An element portion having a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer Equipped with, The first metal plate is a metal support having a gas permeable portion between the first surface and the second surface that allows gas to pass through, The element portion is located on the second surface of the gas permeable portion.

[0124] In one embodiment, (10) the electrochemical cell apparatus has a cell stack comprising the electrochemical cells described in (8) or (9) above.

[0125] In one embodiment, module (11) is an electrochemical cell apparatus of the above (10), The system includes a storage container for housing the aforementioned electrochemical cell apparatus.

[0126] In one embodiment, the module housing device (12) includes the module (11) and Auxiliary equipment for operating the aforementioned module, The system comprises the module and an outer case housing the auxiliary equipment.

[0127] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. Indeed, the embodiments described above can be embodied in a variety of forms. Furthermore, the embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0128] 1 cell 3 Element section 5 Fuel electrode 6 Solid electrolyte layer 8. Air pole 10-cell stack device 30 1st metal plate 40 Second metal plate 50 Metal joints 60 Welded section 61 First welding surface 62 Second welding surface 63 Third welding surface 70 aperture 100 modules 110 Module housing device

Claims

1. A first metal plate having a first surface and a second surface opposite to the first surface, A second metal plate having a third surface facing the first surface and a fourth surface opposite the third surface. Equipped with, The first surface is located at the first end including the first end in the first direction and has a first contact surface extending in a second direction intersecting the first direction. The third surface is located at the first end and has a second contact surface extending in the second direction, The first end has a welded portion where the first metal plate and the second metal plate are welded together. The welded portion has a first welded surface that is continuously connected to the second surface in the second direction. Metal joint.

2. The first welding surface has a first width in the first direction, The maximum value of the first width is W. ｍａｘ Let the minimum value be W. ｍｉｎ When that happens, W ｍｉｎ is W ｍａｘ It is more than 0.5 times that amount. The metal joint according to claim 1.

3. The welded portion further has a second welded surface on the fourth surface. The metal joint according to claim 1.

4. The first welding surface has a first width in the first direction, The second welding surface has a second width in the first direction, The average of the first width is greater than the average of the second width. The metal joint according to claim 3.

5. The welded portion has a third welded surface located between the second surface and the fourth surface at the first end. The metal joint according to claim 1.

6. At least a portion of the third welding surface is connected to the first welding surface. The metal joint according to claim 5.

7. Located between the first contact surface and the second contact surface, and having one or more openings on the first end surface located at the first end, When the length of the first end face in the first direction is L0, and the sum of the lengths of the one or more openings in the first direction is L1, L1 is less than 80% of L0. The metal joint according to claim 1.

8. The metal joint described in claim 1, An element portion having a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer Equipped with, The second metal plate is a metal support having a gas permeable portion between the third surface and the fourth surface that allows gas to pass through, The element portion is located on the fourth surface of the gas permeable portion. Electrochemical cell.

9. The metal joint described in claim 1, An element portion having a solid electrolyte layer, a first electrode and a second electrode sandwiching the solid electrolyte layer Equipped with, The first metal plate is a metal support having a gas permeable portion between the first surface and the second surface that allows gas to pass through, The element portion is located on the second surface of the gas permeable portion. Electrochemical cell.

10. A cell stack comprising the electrochemical cell described in claim 8 or 9 Electrochemical cell apparatus.

11. The electrochemical cell apparatus according to claim 10, A storage container for housing the electrochemical cell apparatus and A module equipped with the following features.

12. The module according to claim 11, Auxiliary equipment for operating the aforementioned module, An outer case housing the module and the auxiliary equipment A module housing device equipped with the following features.

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