Electrochemical cell, electrochemical cell device, module, and module-accommodating device

Abstract

This electrochemical cell includes a first electrode, a first conductive member, and a second conductive member. The first electrode contains a first material having ionic conductivity in which a first element is solid-solubilized, and a second material having electronic conductivity. A first element is solid-solubilized in the first material. The first conductive member contains a second element different from the first element, and a second material. A second conductive member is located between the first electrode and the first conductive member, and contains a first element, a second element, and a second material. The first element is at least one element selected from among Mg, Ca, and rare earth elements. The second element is at least one element selected from among Mg, Ca, Ti, Al, Si, and rare earth elements.

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] Special table 2014-524655 publication

[0004] An electrochemical cell according to one aspect of the embodiment includes a first electrode, a first conductive member, and a second conductive member. The first electrode contains a first material having ionic conductivity and a second material having electronic conductivity. A first element is dissolved in the first material. The first conductive member contains a second element different from the first element and the second material. The second conductive member is located between the first electrode and the first conductive member and contains the first element, the second element, and the second material. The first element is one or more elements selected from Mg, Ca, and rare earth elements. The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements.

[0005] The electrochemical cell device of the present disclosure also includes a cell stack including the electrochemical cell described above.

[0006] The module of the present disclosure includes the electrochemical cell device described above and a container that houses the electrochemical cell device.

[0007] The module housing device of the present disclosure includes the module described above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0008] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. FIG. 1B is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the interconnector side. FIG. 2A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. FIG. 2B is a cross-sectional view taken along line X-X shown in FIG. 2A. FIG. 2C is a top view showing an example of an electrochemical cell device according to the first embodiment. FIG. 3 is a cross-sectional view showing an enlarged region R1 shown in FIG. 1A. FIG. 4 is an external perspective view showing an example of a module according to the first embodiment. FIG. 5 is an exploded perspective view schematically showing an example of a module housing device according to the first embodiment. FIG. 6 is a cross-sectional view of an electrochemical cell device according to the second embodiment. FIG. 7 is a cross-sectional view showing an example of an electrochemical cell according to the second embodiment. FIG. 8 is a cross-sectional view showing an enlarged region R2 shown in FIG. 7. FIG. 9A is a cross-sectional view showing an example of an electrochemical cell according to a third embodiment. FIG. 9B is a cross-sectional view showing another example of an electrochemical cell according to the third embodiment. Fig. 9C is a cross-sectional view showing another example of an electrochemical cell according to embodiment 3. Fig. 10 is an enlarged cross-sectional view of region R3 shown in Fig. 9A.

[0009] The above-described fuel cell stack device has room for improvement in terms of durability.

[0010] 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.

[0011] 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.

[0012] 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.

[0013] 1A to 1C, an electrochemical cell constituting an electrochemical cell device according to a first embodiment will be described using an example of a solid oxide fuel cell. 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.

[0014] FIG. 1A is a cross-sectional view showing an example of an electrochemical cell according to the first embodiment. FIG. 1B is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a side view of an example of an electrochemical cell according to the first embodiment, viewed from the interconnector side. Note that FIGS. 1A to 1C 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.

[0015] 1A to 1C, the cell 1 is a hollow, flat, elongated plate. As shown in Fig. 1B, the shape of the entire cell 1 as viewed from the side is, for example, a rectangle with a side length in the length direction L of 5 cm to 50 cm and a length in the width direction W perpendicular to the length direction L of 1 cm to 10 cm. The thickness of the entire cell 1 in the thickness direction T is, for example, 1 mm to 5 mm.

[0016] 1A, the cell 1 includes a conductive support substrate 2, an element portion 3, and an interconnector 4. The support substrate 2 is columnar, having a pair of opposing first and second surfaces n1 and n2, and a pair of arc-shaped side surfaces m connecting the first and second surfaces n1 and n2.

[0017] The element section 3 is provided on a first surface n1 of the support substrate 2. The element section 3 has an anode 5, a solid electrolyte layer 6, and a cathode 8. In the example shown in FIG. 1A , an interconnector 4 is located on a second surface n2 of the cell 1. The cell 1 may also have an intermediate layer 7 between the solid electrolyte layer 6 and the cathode 8.

[0018] 1B, the air electrode 8 does not extend to the lower end of the cell 1. At the lower end of the cell 1, only the solid electrolyte layer 6 is exposed on the surface of the first face n1. As shown in FIG. 1C, the interconnector 4 may extend to the lower end of the cell 1. At the lower end of the cell 1, the interconnector 4 and the solid electrolyte layer 6 are exposed on the surface. As shown in FIG. 1A, the solid electrolyte layer 6 is exposed on the surface of a pair of arc-shaped side faces m of the cell 1. The interconnector 4 does not have to extend to the lower end of the cell 1.

[0019] Each of the components that make up the cell 1 will be described below.

[0020] The support substrate 2 has gas flow channels 2a therein through which gas flows. The example of the support substrate 2 shown in FIG. 1A has six gas flow channels 2a. The support substrate 2 has gas permeability, and allows the fuel gas flowing through the gas flow channels 2a to permeate to the anode 5. The support substrate 2 may be conductive. The conductive support substrate 2 collects electricity generated in the element section 3 to the interconnector 4.

[0021] The material of the support substrate 2 includes, for example, an iron-group metal component and an inorganic oxide. The iron-group metal component may be, for example, Ni (nickel) and / or NiO. The inorganic oxide may be, for example, a specific rare earth element oxide. The rare earth element oxide may include, for example, one or more rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. Details of the support substrate 2 will be described later.

[0022] The fuel electrode 5 may be made of porous conductive ceramics. Examples of the material for the fuel electrode 5 include calcium oxide, magnesium oxide, and ZrO in which a rare earth element oxide is solid-solved. ２ and 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. ２The stabilized zirconia may also be referred to as stabilized zirconia. The stabilized zirconia may include partially stabilized zirconia. The fuel electrode 5 is an example of a first electrode.

[0023] The fuel electrode 5 is made of cerium oxide (CeO ２ The fuel electrode 5 may contain BaMO in which a rare earth element is dissolved. ３ , SrMO ３ (wherein M is Zr and / or Ce).

[0024] ZrO in which rare earth element oxide is solid-dissolved in the fuel electrode 5 ２ , CeO ２ , BaMO ３ , SrMO ３ The content of these may be in the range of 35% to 65% by volume. The content of Ni and / or NiO may be in the range of 65% to 35% by volume. The porosity of the anode 5 may be 15% or more, particularly in the range of 20% to 40%. The thickness of the anode 5 may be 1 μm to 30 μm.

[0025] 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.

[0026] The solid electrolyte layer 6 contains Zr. The material of the solid electrolyte layer 6 is, for example, ZrO in which 3 mol % to 15 mol % of a rare earth element oxide, calcium oxide, or magnesium oxide is solid-solved. 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 material of the solid electrolyte layer 6 may be, for example, stabilized zirconia containing Sc, Y, or Yb. The solid electrolyte layer 6 may be, for example, BaZrO in which a rare earth element such as Sc, Y, La, Nd, Sm, Gd, Dy, or Yb is dissolved. ３ , SrZrO ３ It may contain perovskite type compounds such as:

[0027] The air electrode 8 is gas permeable. The air electrode 8 is an example of a second electrode. The open porosity of the air electrode 8 may be in the range of, for example, 20% to 50%, and particularly 30% to 50%.

[0028] 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.

[0029] 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.

[0030] Furthermore, when the element section 3 has the intermediate layer 7, the intermediate layer 7 functions as a diffusion suppression layer. When elements such as Sr (strontium) contained in the air electrode 8 diffuse into the solid electrolyte layer 6, the solid electrolyte layer 6 is filled with, for example, SrZrO ３ The intermediate layer 7 is formed as a resistive layer by making it difficult for Sr to diffuse. ３ It makes it difficult for other oxides with electrical insulating properties to form.

[0031] The material of the intermediate layer 7 is not particularly limited as long as it generally prevents diffusion of elements between the air electrode 8 and the solid electrolyte layer 6. The material of the intermediate layer 7 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).

[0032] Furthermore, the interconnector 4 is dense and makes it difficult for leakage of the fuel gas flowing through the gas flow passage 2a located inside the support substrate 2 and the oxygen-containing gas flowing outside the support substrate 2 to occur. The interconnector 4 may have a relative density of 93% or more, particularly 95% or more.

[0033] The material of the interconnector 4 is a lanthanum chromite-based perovskite oxide (LaCrO ３ -based oxides), lanthanum strontium titanium-based perovskite-type oxides (LaSrTiO ３ These materials are electrically conductive and are not easily reduced or oxidized even when in contact with a fuel gas such as a hydrogen-containing gas and an oxygen-containing gas such as air. Alternatively, a metal or an alloy may be used as the material for the interconnector 4.

[0034] <Configuration of Electrochemical Cell Device> Next, an electrochemical cell device according to this embodiment using the above-described electrochemical cell will be described with reference to Figures 2A to 2C. Figure 2A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. Figure 2B is a cross-sectional view taken along line XX shown in Figure 2A. Figure 2C is a top view showing an example of an electrochemical cell device according to the first embodiment.

[0035] As shown in FIG. 2A, the cell stack device 10 includes a cell stack 11 having a plurality of cells 1 arranged (stacked) in the thickness direction T of the cells 1 (see FIG. 1A), and a fixing member 12.

[0036] 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, for example, metal and are electrically conductive.

[0037] 2B, 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.

[0038] 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.

[0039] In the example shown in Fig. 2A, fuel gas is stored in an internal space 22 formed by a support 15, which is the support member 14, and a gas tank 16. A gas circulation pipe 20 is connected to the gas tank 16. The fuel gas is supplied to the gas tank 16 through this gas circulation pipe 20, and is supplied from the gas tank 16 to a gas flow path 2a (see Fig. 1A) inside the cell 1. The fuel gas supplied to the gas tank 16 is generated in a reformer 102 (see Fig. 4), which will be described later.

[0040] 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.

[0041] In the example shown in FIG. 2A , the cell stack device 10 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 each of the supports 15. The gas tank 16 has two through-holes on its top surface. A support 15 is disposed in each of the through-holes. An internal space 22 is formed by the one gas tank 16 and the two supports 15. Although FIG. 2A shows the cell stack device 10 having two rows of cell stacks 11, the cell stack device may have one row of cell stacks 11, or three or more rows of cell stacks 11.

[0042] The shape of the insertion hole 15a is, for example, an oval shape when viewed from above. For example, the length of the insertion hole 15a in the arrangement direction of the cells 1, i.e., the thickness direction T, 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 W (see FIG. 1A ).

[0043] 2B , 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.

[0044] 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.

[0045] 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.

[0046] 2B , a conductive member 18 is interposed between adjacent cells 1 among the plurality of cells 1. The conductive member 18 electrically connects the anode 5 of one adjacent cell 1 to the cathode 8 of the other cell 1 in series. More specifically, the conductive member 18 connects the interconnector 4 electrically connected to the anode 5 of one adjacent cell 1 to the cathode 8 of the other cell 1. When the interconnector 4 is made of a metal or an alloy, the interconnector 4 and the conductive member 18 may be integrated, or the conductive member 18 may also serve as the interconnector 4.

[0047] 2B, an end current collecting member 17 is electrically connected to the cell 1 positioned outermost in the arrangement direction of the multiple cells 1. The end current collecting member 17 is connected to a conductive portion 19 that protrudes outside 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. 2A.

[0048] 2C, 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.

[0049] The positive terminal 19A is a positive electrode when the power generated by the cell stack 11 is output to the outside, and is electrically connected to the positive-side end current collecting member 17 of the cell stack 11A. The negative terminal 19B is a negative electrode when the power generated by the cell stack 11 is output to the outside, and is electrically connected to the negative-side end current collecting member 17 of the cell stack 11B.

[0050] 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.

[0051] <Details of Electrochemical Cell> Next, details of the electrochemical cell including the support substrate 2 according to the first embodiment will be described with reference to Fig. 3. Fig. 3 is an enlarged cross-sectional view of a region R1 shown in Fig. 1A.

[0052] 3 , the cell 1 includes a solid electrolyte layer 6, an anode 5 as a first electrode, a support substrate 2 as a first conductive member, and a second conductive member 2b. For example, the first electrode may be made of an ion-conductive material containing a first element to improve the performance of the element section 3, while the first conductive member may be made of a material containing a second element different from the first element. This allows the thermal expansion coefficients of the first electrode and the first conductive member to be adjusted, making it difficult for the first electrode to peel off from the first conductive member.

[0053] The solid electrolyte layer 6 contains a first material including a first element. The first element may be solid-solved in the first material. The first element is one or more elements selected from Mg, Ca, and rare earth elements. The rare earth elements may include, for example, one or more elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. The first material may include an oxide-based solid electrolyte material in which an oxide of the first element is solid-solved. The first material may include, for example, stabilized zirconia containing Sc, Y, or Yb.

[0054] The anode 5 contains a first material having ionic conductivity and a second material having electronic conductivity. The second material may be, for example, Ni or NiO.

[0055] The support substrate 2 contains a second element and a second material. The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements, and is an element different from the first element. The support substrate 2 may contain an oxide of the second element. For example, the support substrate 2 may contain Sc ２ O ３ , Y ２ O ３ , or Yb ２ O ３ It may also include the following.

[0056] The second conductive member 2b is located between the fuel electrode 5 as a first electrode and the support substrate 2 as a first conductive member. The second conductive member 2b contains a first element, a second element, and a second material. The second conductive member 2b may contain an oxide of the first element and an oxide of the second element. The second conductive member 2b may also contain the first material.

[0057] The contents of the first element, the second element, the first material, and the second material can be confirmed by, for example, elemental analysis using EPMA. Specifically, for example, a cross section of the element portion 3 in the stacking direction is mirror-polished, and a predetermined area is subjected to semi-quantitative analysis of the first element, the second element, the first material, and the second material, respectively, to calculate the respective contents per unit area. The content of the first element may be evaluated, for example, as the ratio of the first element to the total of the metal elements constituting the first element, the second element, and the first material.

[0058] In this way, second conductive member 2b containing the first element contained in anode 5 and the second element contained in support substrate 2 is located between anode 5 and support substrate 2, thereby reducing the difference in thermal expansion between anode 5 and support substrate 2. Therefore, cell 1 according to this embodiment can improve durability.

[0059] Furthermore, the content of the first element contained in the anode 5 may decrease toward the support substrate 2 in the cross section of the element portion 3 in the stacking direction. The content of the first element in the anode 5 may be distributed so as to decrease toward the boundary between the anode 5 and the second conductive member 2b. This further improves the durability of the cell 1.

[0060] The fuel electrode 5, the second conductive member 2b, and the support substrate 2 may have a portion where the content of the first element takes a maximum value and / or a minimum value in a cross section in the stacking direction of the element portion 3. A maximum value is a local maximum value, and a minimum value is a local minimum value.

[0061] The boundary between second conductive member 2 b and anode 5 is, for example, the portion where the content of the first element is at a minimum and closest to solid electrolyte layer 6. The content of the first element contained in the boundary between second conductive member 2 b and anode 5 may be, for example, ⅓ or less of the content of the first element in the anode 5 near solid electrolyte layer 6.

[0062] The boundary between the second conductive member 2b and the support substrate 2 is, for example, a portion where the distance from the solid electrolyte layer 6 is greater than the distance to the boundary between the second conductive member 2b and the fuel electrode 5 and where the content of the first element is equal to the content of the first element at the boundary between the second conductive member 2b and the fuel electrode 5.

[0063] The second conductive member 2b may have a portion between the boundary between the second conductive member 2b and the fuel electrode 5 and the boundary between the second conductive member 2b and the support substrate 2, where the content of the first element has a maximum value.

[0064] The second conductive member 2b may contain a larger amount of the first material containing the first element in a portion closer to the anode 5 than in a portion farther from the anode 5. This makes the anode 5 less likely to peel off from the support substrate 2. The second conductive member 2b may contain a larger amount of an oxide of the first element in a portion closer to the support substrate 2 than in a portion farther from the support substrate 2. This makes the anode 5 less likely to peel off from the support substrate 2. The second conductive member 2b may contain a first material containing the second element in a portion closer to the anode 5.

[0065] The content of the second material in the fuel electrode 5, the support substrate 2, and the second conductive member 2b may be the same or different.

[0066] <Module> Next, a module according to this embodiment using the electrochemical cell device described above will be described with reference to Fig. 4. Fig. 4 is an external perspective view showing the module according to the first embodiment. Fig. 4 shows a state in which the front and rear surfaces, which are parts of the storage container 101, have been removed and the cell stack device 10 of the fuel cell stored inside has been pulled out to the rear.

[0067] 4, the module 100 includes a storage container 101 and a cell stack device 10 housed in the storage container 101. A reformer 102 is disposed above the cell stack device 10.

[0068] 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.

[0069] The fuel gas produced in the reformer 102 is supplied to the gas flow channel 2 a of the cell 1 (see FIG. 1A) through the gas distribution pipe 20 , the gas tank 16 , and the support member 14 .

[0070] 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.

[0071] In such a module 100, as described above, the highly durable cell stack device 10 is housed therein, and thus the module 100 can be made highly durable.

[0072] <Module Enclosure Device> Fig. 5 is an exploded perspective view showing 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. 4, and auxiliary equipment (not shown). The auxiliary equipment operates the module 100. The module 100 and the auxiliary equipment are housed in the outer case 111. Note that some components are omitted in Fig. 5.

[0073] An exterior case 111 of a module accommodating device 110 shown in Fig. 5 has support columns 112 and an exterior plate 113. A partition plate 114 divides the interior of the exterior case 111 into upper and lower sections. The space above the partition plate 114 in the exterior case 111 is a module accommodating chamber 115 that accommodates the module 100, and the space below the partition plate 114 in the exterior case 111 is an auxiliary equipment accommodating chamber 116 that accommodates auxiliary equipment for operating the module 100. Note that in Fig. 5, the auxiliary equipment accommodated in the auxiliary equipment accommodating chamber 116 is omitted from the illustration.

[0074] 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.

[0075] 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.

[0076] In the above embodiment, a case where a hollow flat plate-type support substrate is used is exemplified, but the present invention can also be applied to a cell stack device that uses a cylindrical support substrate.

[0077] Second Embodiment Next, an electrochemical cell and an electrochemical cell device according to a second embodiment will be described with reference to FIGS.

[0078] In the above-described embodiment, a so-called "vertical stripe type" is exemplified in which only one element unit including a fuel electrode layer, a solid electrolyte layer, and an air electrode layer is provided on the surface of a support substrate. However, the present invention can also be applied to a horizontal stripe type electrochemical cell device in which so-called "horizontal stripe type" electrochemical cells are arranged, in which element units are provided at multiple locations spaced apart from each other on the surface of a support substrate and adjacent element units are electrically connected.

[0079] Fig. 6 is a cross-sectional view of an electrochemical cell device according to the second embodiment, and Fig. 7 is a transverse cross-sectional view showing an example of an electrochemical cell according to the second embodiment.

[0080] 6, in a cell stack device 10A according to the second embodiment, multiple cells 1A extend in a longitudinal direction L from a pipe 22a through which fuel gas flows. Each cell 1A has multiple element units 3 on a support substrate 2. A gas flow path 2a through which fuel gas flows from the pipe 22a is provided inside the support substrate 2.

[0081] The cells 1A are electrically connected to one another via connecting members 31. The connecting members 31 are located between the element units 3 of the cells 1A, and connect the adjacent cells 1A. Specifically, the connecting members 31 electrically connect the air electrode 8 of the element unit 3 of one of the adjacent cells 1A to the fuel electrode 5 of the element unit 3 of the other cell 1A.

[0082] 7, the cell 1A includes a support substrate 2, a pair of element units 3, and a sealing unit 30. The support substrate 2 is columnar and has a pair of opposing flat surfaces, that is, a first surface n1 and a second surface n2, and a pair of arc-shaped side surfaces m connecting the first surface n1 and the second surface n2.

[0083] The pair of element portions 3 are located opposite each other on the first surface n1 and the second surface n2 of the support substrate 2. The sealing portion 30 is located so as to cover the side surface m of the support substrate 2.

[0084] The cell 1A may have a symmetrical shape with respect to a plane that passes through the center in the thickness direction T and is parallel to the first surface n1 and the second surface n2 of the support substrate 2. The element unit 3 includes an anode 5, a solid electrolyte layer 6, and a cathode 8. The element unit 3 may include an intermediate layer 7 between the solid electrolyte layer 6 and the cathode 8.

[0085] Fig. 8 is an enlarged cross-sectional view of region R2 shown in Fig. 7. As shown in Fig. 8, cell 1A includes solid electrolyte layer 6, fuel electrode 5, and insulating support substrate 2.

[0086] The solid electrolyte layer 6 contains a first material in which a first element is dissolved. The first element is one or more elements selected from Mg, Ca, and rare earth elements. The first material may include, for example, stabilized zirconia containing Sc, Y, or Yb.

[0087] The anode 5 includes an anode functional layer 5 a as a first electrode, an anode current collecting layer 5 b as a first conductive member, and a second conductive member 5 c. The anode functional layer 5 a contains a first material having ion conductivity and a second material having electron conductivity.

[0088] The anode current collecting layer 5b is a first conductive member and contains a second element and a second material. The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements, and is an element different from the first element. The anode current collecting layer 5b may contain, for example, stabilized zirconia containing Sc, Y, Yb, or the like. The insulating support substrate 2 may or may not contain stabilized zirconia containing, for example, Sc, Y, or Yb, or the like.

[0089] The second conductive member 5c is located between the anode functional layer 5a (as the first electrode) and the anode current collecting layer 5b (as the first conductive member). The second conductive member 5c contains the first element, the second element, and the second material.

[0090] In this manner, the second conductive member 5 c containing the first element contained in the anode functional layer 5 a and the second element contained in the anode current collecting layer 5 b is located between the anode functional layer 5 a and the anode current collecting layer 5 b, thereby reducing the difference in thermal expansion between the anode functional layer 5 a and the anode current collecting layer 5 b. As a result, the durability of the cell 1A according to this embodiment can be improved.

[0091] 9A is a cross-sectional view showing an example of an electrochemical cell according to a third embodiment, and FIGS. 9B and 9C are cross-sectional views showing another example of the electrochemical cell according to the third embodiment.

[0092] As shown in FIGS. 9A to 9C , the cell 1B includes an element unit 3B including an anode 5, a solid electrolyte layer 6, and a cathode 8, and a support substrate 2. The element unit 3B may include an intermediate layer 7 between the solid electrolyte layer 6 and the cathode 8. The support substrate 2 has through-holes or pores in a portion in contact with the element unit 3B, and includes a member 120 located outside the gas flow path 2a. The support substrate 2 allows gas to flow between the gas flow path 2a and the element unit 3B. The support substrate 2 may be composed of, for example, one or more metal plates. The material of the metal plate may contain chromium. The metal plate may have a conductive coating layer. The support substrate 2 electrically connects adjacent cells 1B. The element unit 3B is bonded to the support substrate 2 by bonding materials 23 and 24.

[0093] In the example shown in Fig. 9A, the side surface of the anode 5 is covered with a solid electrolyte layer 6, which airtightly seals a gas flow channel 2a through which the fuel gas flows. As shown in Fig. 9B, the side surface of the anode 5 may be covered and sealed with a dense sealant 9 containing glass or ceramic. The sealant 9 covering the side surface of the anode 5 may have electrical insulating properties.

[0094] Furthermore, the gas flow path 2a of the support substrate 2 may be formed by a member 120 having projections and recesses as shown in FIG. 9C.

[0095] Fig. 10 is an enlarged cross-sectional view of region R3 shown in Fig. 9A. As shown in Fig. 10, cell 1B includes solid electrolyte layer 6, fuel electrode 5 as a first electrode, bonding material 23 as a first conductive member, and bonding material 24 as a second conductive member. Note that Fig. 10 can also be applied to the examples of Figs. 9B and 9C.

[0096] The solid electrolyte layer 6 contains a first material in which a first element is dissolved in a solid solution. The first element is one or more elements selected from Mg, Ca, and rare earth elements.

[0097] The fuel electrode 5 contains a first material having ion conductivity and a second material having electron conductivity.

[0098] The bonding material 23 contains a second element and a second material. The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements, and is an element different from the first element. The bonding material 23 may contain an oxide of the second element. For example, the bonding material 23 may contain TiO ２ , Al ２ O ３ , SiO ２ It may also include the following.

[0099] The bonding material 24 serving as the second conductive member is located between the fuel electrode 5 serving as the first electrode and the bonding material 23 serving as the first conductive member. The bonding material 24 contains a first element, a second element, and a second material.

[0100] In this way, bonding material 24 containing the first material that includes the first element contained in anode 5 and the second element contained in bonding material 23 is positioned between anode 5 and bonding material 23, thereby reducing the difference in thermal expansion between anode 5 and bonding material 23. Therefore, cell 1B according to this embodiment can improve durability.

[0101] Other Embodiments Next, electrochemical cell devices according to other embodiments will be described.

[0102] 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. The electrolysis cell has a first electrode layer and a second electrode layer, 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 an electrolysis cell, electrolysis cell stack device, electrolysis module, and electrolysis device can improve durability.

[0103] 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.

[0104] In one embodiment, (1) an electrochemical cell includes: a first electrode containing a first material having ionic conductivity in which a first element is dissolved, and a second material having electronic conductivity; a first conductive member containing a second element different from the first element and the second material; and a second conductive member located between the first electrode and the first conductive member, containing the first element, the second element, and the second material, wherein the first element is one or more elements selected from Mg, Ca, and rare earth elements, and the second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements.

[0105] (2) In the electrochemical cell of (1) above, the first conductive member may contain an oxide of the second element.

[0106] (3) In the electrochemical cell of (1) or (2) above, the second conductive member may contain an oxide of the first element and an oxide of the second element.

[0107] (4) In the electrochemical cell of any one of (1) to (3) above, the second conductive member may contain the first material.

[0108] (5) In the electrochemical cell of any one of (1) to (4) above, the second conductive member may have a portion where the content of the first element takes a maximum value between the boundary between the first electrode and the second conductive member and the boundary between the first conductive member and the second conductive member.

[0109] In one embodiment, the electrochemical cell device (6) has a cell stack including any one of the electrochemical cells (1) to (5) above.

[0110] In one embodiment, (7) a module includes the electrochemical cell device of (6) above, and a container that houses the electrochemical cell device.

[0111] In one embodiment, (8) a module housing device includes the module of (7) above, an auxiliary device for operating the module, and an exterior case for housing the module and the auxiliary device.

[0112] In one embodiment, (9) an electrochemical cell includes: a first electrode containing a first material containing a first element and having ionic conductivity and a second material having electronic conductivity; a first conductive member containing a second element different from the first element and the second material; and a second conductive member located between the first electrode and the first conductive member and containing the first element, the second element, and the second material, wherein the first element is one or more elements selected from Mg, Ca, and rare earth elements, and the second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements.

[0113] 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.

[0114] REFERENCE SIGNS LIST 1 cell 2 support substrate 2b second conductive member 5 fuel electrode 6 solid electrolyte layer 10 cell stack device 11 cell stack 12 fixing member 13 fixing material 14 support member 15 support body 16 gas tank 17 end current collecting member 18 conductive member 100 module 110 module accommodating device

Claims

1. a first electrode containing a first material having ionic conductivity in which a first element is dissolved and a second material having electronic conductivity; a first conductive member containing a second element different from the first element and the second material; a second conductive member located between the first electrode and the first conductive member and containing the first element, the second element, and the second material; Equipped with the first element is one or more elements selected from Mg, Ca, and rare earth elements; The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements. Electrochemical cell.

2. The first conductive member contains an oxide of the second element.

10. The electrochemical cell of claim 1.

3. The second conductive member contains an oxide of the first element and an oxide of the second element.

10. The electrochemical cell of claim 1.

4. The second conductive member contains the first material.

10. The electrochemical cell of claim 1.

5. The second conductive member has a portion where the content of the first element takes a maximum value between the boundary between the first electrode and the second conductive member and the boundary between the first conductive member and the second conductive member.

10. The electrochemical cell of claim 1.

6. A first electrode containing a first material having ionic conductivity and a second material having electronic conductivity; a first conductive member containing a second element different from the first element and the second material; a second conductive member located between the first electrode and the first conductive member and containing the first element, the second element, and the second material; Equipped with the first element is one or more elements selected from Mg, Ca, and rare earth elements; The second element is one or more elements selected from Mg, Ca, Ti, Al, Si, and rare earth elements. Electrochemical cell.

7. A cell stack including the electrochemical cell according to any one of claims 1 to 6. Electrochemical cell apparatus.

8. The electrochemical cell device according to claim 7 ; a container for housing the electrochemical cell device; A module comprising:

9. A module according to claim 8; Auxiliary equipment for operating the module; an exterior case that houses the module and the auxiliary equipment; A module housing device comprising: