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

Abstract

An electrochemical cell according to the present invention comprises an element part and a passage member. The passage member comprises: a first flat part facing the element part; and a plurality of protrusions that protrude from the first flat part toward the element part. The passage member comprises: a supply port positioned at a first end of the passage member in a first direction in which a first gas flows; and a discharge port positioned at a second end on the side opposite the first end in the first direction. When viewed in a plan view from the element part side, a line segment connecting the first end and the second end intersects at least one of the plurality of protrusions.

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] International Publication No. 2020 / 218431

[0004] An electrochemical cell according to one aspect of the embodiment includes an element portion and a flow path member. The flow path member has a first flat portion facing the element portion and a plurality of protruding portions protruding from the first flat portion toward the element portion. The flow path member has a supply port located at a first end in a first direction in which a first gas flows and an outlet port located at a second end opposite the first end in the first direction. When viewed in plan from the element portion side, a line segment connecting the first end and the second end intersects with at least one of the plurality of protruding portions.

[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 plan view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a plan view of an example of an electrochemical cell according to the first embodiment, viewed from the flow path member side. FIG. 1D is a cross-sectional view showing another example of an electrochemical cell according to the first embodiment. FIG. 2A is a cross-sectional view taken along line A-A in FIG. 1C. FIG. 2B is an enlarged plan view of region R1 shown in FIG. 1C. FIG. 3A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. FIG. 3B is a cross-sectional view taken along line X-X in FIG. 3A. FIG. 3C is a top view showing an example of an electrochemical cell device according to the first embodiment. 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. 6A is a plan view showing an example of a convex portion provided in a flow path member. FIG. 6B is a plan view showing an example of a convex portion provided in a flow path member. FIG. 6C is a plan view showing an example of a convex portion provided in a flow path member. FIG. 7A is a plan view showing another example of convex portions provided on a flow path member. FIG. 7B is a plan view showing another example of convex portions provided on a flow path member. FIG. 7C is a plan view showing another example of convex portions provided on a flow path member. FIG. 7D is a plan view showing another example of convex portions provided on a flow path member. FIG. 7E is a plan view showing another example of convex portions provided on a flow path member. FIG. 8A is a perspective view showing an example of an electrochemical cell device according to a second embodiment. FIG. 8B is a partial cross-sectional view of the electrochemical cell device shown in FIG. 8A. FIG. 8C is an enlarged view of region R2 shown in FIG. 8B.

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

[0010] Therefore, it is desired to provide an electrochemical cell, an electrochemical cell device, a module, and a module housing device that can improve performance.

[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 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 plan view of an example of an electrochemical cell according to the first embodiment, viewed from the air electrode side. FIG. 1C is a plan view of an example of an electrochemical cell according to the first embodiment, viewed from the flow path member 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 illustrate a three-dimensional Cartesian coordinate system including a Z-axis, with the vertically upward direction being the positive direction and the vertically downward direction being the negative direction. This Cartesian coordinate system may also be shown in other drawings used in the following explanation. Furthermore, the same reference numerals are used to designate components similar to those of the electrochemical cells shown in FIGS. 1A to 1C, and their explanations will be omitted or simplified.

[0016] 1A , the electrochemical cell device according to this embodiment includes a cell 1. The cell 1 includes an element section 3, a support member 2, and a flow path member 30. The element section 3 includes a cathode 8, a solid electrolyte layer 6, and a fuel electrode 5.

[0017] The air electrode 8 is a first electrode that comes into contact with an oxygen-containing gas. The air electrode 8 has gas permeability. The open porosity of the air electrode 8 may be, for example, in the range of 20% to 50%, particularly 30% to 50%. The open porosity of the air electrode 8 may also be referred to as the porosity of the air electrode 8.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] The material of the solid electrolyte layer 6 is, for example, ZrO in which 3 mol % to 15 mol % of rare earth element oxide is dissolved. ２ The rare earth element oxide may contain, for example, one or more rare earth elements selected from Sc, Y, La, Nd, Sm, Gd, Dy, and Yb. The solid electrolyte layer 6 may be, for example, ZrO in which Yb, Sc, or Gd is solid-solved. ２ and CeO in which La, Nd or Yb is solid-solved. ２ and BaZrO in which Sc or Yb is solid-solved. ３ and BaCeO in which Sc or Yb is solid-solved. ３ may include:

[0022] The anode 5 is a second electrode that comes into contact with the fuel gas, which is a reducing gas. The anode 5 has gas permeability. The open porosity of the anode 5 may be, for example, in the range of 30% to 50%, particularly 35% to 45%. The open porosity of the anode 5 may also be referred to as the porosity or void ratio of the anode 5.

[0023] A generally known material can be used for the fuel electrode 5. The fuel electrode 5 is made of a porous conductive ceramic, such as calcium oxide, magnesium oxide, or ZrO in which a rare earth element oxide is solid-solved. 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. ２ The stabilized zirconia may contain partially stabilized zirconia. The anode 5 is made of CeO in which La, Nd, or Yb is solid-solved. ２ may include:

[0024] The element unit 3 may also have an intermediate layer (not shown) located between the solid electrolyte layer 6 and the air electrode 8. When the element unit 3 has an intermediate layer, the intermediate layer functions, for example, as a diffusion suppression layer. For example, when Sr (strontium) contained in the air electrode 8 diffuses into the solid electrolyte layer 6, SrZrO ３ The intermediate layer is formed by making it difficult for a specific element, such as Sr, to diffuse, and thus the resistance layer is formed. ３ This makes it difficult for a resistive layer such as the above to form.

[0025] The material of the intermediate layer 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 is, for example, cerium oxide (CeO ２ ) may be included. Examples of such rare earth elements include Gd (gadolinium) and Sm (samarium).

[0026] The cell 1 may further include a constraining layer located between the element portion 3 and the support member 2. The constraining layer cooperates with the solid electrolyte layer 6 to make the element portion 3 less susceptible to warping, bending, and the like.

[0027] The material of the constraining layer exhibits a shrinkage rate similar to that of the material of the solid electrolyte layer 6 during firing. The material of the constraining layer may be the same as the material of the solid electrolyte layer 6. The element unit 3 obtained by sandwiching the material of the anode 5 of the element unit 3 between the material of the solid electrolyte layer 6 and the material of the constraining layer and firing the resulting element unit 3 has little warping or deformation.

[0028] The constraining layer may or may not be gas permeable. When the constraining layer has gas barrier properties comparable to those of the solid electrolyte layer 6, the constraining layer can be partially disposed so as not to obstruct the inflow of fuel gas to the anode 5.

[0029] The cell 1 may further include a gas diffusion layer. The gas diffusion layer is located between the anode 5 and the support member 2. The gas diffusion layer has gas permeability and allows the fuel gas flowing through a flow path 2a (described later) to pass through to the anode 5. The open porosity of the gas diffusion layer may be in the range of, for example, 30% to 50%, particularly 35% to 45%.

[0030] The material of the gas diffusion layer may be a porous conductive ceramic, such as a ceramic containing calcium oxide, magnesium oxide, or stabilized zirconia or partially stabilized zirconia in which a rare earth element oxide is solid-solved, and Ni and / or NiO. The rare earth element oxide may contain a plurality of rare earth elements selected from, for example, Sc, Y, La, Nd, Sm, Gd, Dy, and Yb.

[0031] The cell 1 may further include an adhesive material. The adhesive material is located between the element portion 3 and the support member 2. The adhesive material bonds the element portion 3 and the support member 2 together, and fixes the element portion 3 to the support member 2.

[0032] The adhesive may be conductive. For example, the adhesive may be a mixture of conductive particles such as Ni and TiO ２ , rare earth element oxides (Y ２ O ３ , CeO２ etc.), transition metal oxides (Fe ２ O ３ The inorganic oxide may include inorganic oxides such as SiO 2 , CuO, etc.

[0033] The adhesive may be gas permeable. The solid electrolyte layer 6 may be positioned so as to cover the side surface of the adhesive.

[0034] The support member 2 is electrically conductive. The support member 2 may be, for example, a metal plate containing chromium. The support member 2 may be, for example, a stainless steel such as a ferritic stainless steel or an austenitic stainless steel having high heat resistance. The support member 2 may be, for example, a nickel-chromium alloy or an iron-chromium alloy. The support member 2 may contain, for example, a metal oxide. The support member 2 may have a coating covering the surface. The support member 2 does not have to have a coating on the surface.

[0035] The support member 2 may also have openings penetrating in the thickness direction (Y-axis direction). Fuel gas flowing through a flow path 2a, which will be described later, is supplied to the fuel electrode 5 of the element section 3 through these openings. The diameter of the openings may be, for example, 0.1 mm to 0.5 mm, particularly 0.3 mm to 0.4 mm. The aperture ratio in the region where the openings are formed may be, for example, 10% or more. The support member 2 may have a coating covering the wall surfaces of the openings. The support member 2 does not need to have a coating on the wall surfaces of the openings.

[0036] The support member 2 may be gas permeable, for example. In such a case, the support member 2 does not need to have an opening penetrating in the thickness direction (Y-axis direction).

[0037] The flow path member 30 is located between the air electrode 8 of the element section 3 and the support member 2. The material of the flow path member 30 is a dense metal or alloy. The flow path member 30 has a surface 31 and a surface 32. The flow path member 30 makes it difficult for the oxygen-containing gas flowing on the surface 31 side and the fuel gas flowing on the surface 32 side to leak. The flow path member 30 may have a coating layer. For example, the surface 31 of the flow path member 30 may have a coating layer that is oxidation-resistant, and the surface 32 may have a coating layer that is reduction-resistant. These coating layers may be conductive.

[0038] The flow path member 30 is fixed and electrically joined to the support member 2 by, for example, welding or the like at the contact portion. The flow path member 30 may be fixed and electrically joined to the support member 2 by a conductive sealing material, brazing material, or the like. A flow path 2a through which the fuel gas flows is located between the surface 32 of the flow path member 30 and the support member 2. The fuel gas flowing through the flow path 2a permeates the support member 2 and is supplied to the anode 5. The flow path member 30 may have one or more protrusions protruding from the surface 32 toward the support member 2.

[0039] The surface 31 is fixed to the air electrode 8 via, for example, a conductive adhesive and electrically joined thereto. A space is located between the flow path member 30 and the air electrode 8, through which an oxygen-containing gas flows.

[0040] 1C , the surface 31 of the flow path member 30 facing the air electrode 8 may have a first portion 311 and a second portion 312. The first portion 311 is located in the center in the X-axis direction facing the air electrode 8. The second portions 312 are located at both ends in the X-axis direction adjacent to the first portion 311.

[0041] The flow path member 30 has a first end 41 and a second end 42 located at opposite ends in the Z-axis direction. The oxygen-containing gas flows, for example, from the first end 41 side toward the second end 42 side between the first portion 311 of the surface 31 and the air electrode 8. Details of the flow path member 30 will be described later.

[0042] 1D is a cross-sectional view showing another example of the electrochemical cell according to the first embodiment. As shown in FIG. 1D, a sealant 9 different from the solid electrolyte layer 6 may be positioned on the side surface 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. Examples of crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO system, La２ O ３ -B ２ O ３ -ZnO-based, SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２ - An MgO-based material may be used. The sealing material 9 may have electrical insulating properties.

[0043] <Details of Flow Channel Member> Next, details of the flow channel member 30 will be further described with reference to Figures 1A to 1C and 2A to 2B. Figure 2A is a cross-sectional view taken along line AA shown in Figure 1C. Figure 2B is an enlarged plan view of region R1 shown in Figure 1C.

[0044] The first portion 311 of the flow path member 30 has a flat portion 31a as a first flat portion and a plurality of protrusions 31b. The flat portion 31a is positioned so as to face the element portion 3.

[0045] The multiple protrusions 31b are positioned so as to protrude from the flat portion 31a toward the element unit 3. As shown in FIG. 2A , the protrusions 31b have tops 31c facing the element unit 3. The tops 31c may be in contact with the element unit 3. This increases the amount of current per unit time flowing between the air electrode 8 of the element unit 3 and the flow path member 30, improving power generation performance. The tops 31c may have flat portions serving as second flat portions. This increases the contact area between the air electrode 8 of the element unit 3 and the flow path member 30, further improving the power generation performance of the cell 1. Here, the flat portion 31a serving as the first flat portion and the flat portion serving as the second flat portion located at the tops 31c refer to portions that are generally parallel to the surface of the element unit 3 that faces the flow path member 30. The flat portion may have irregularities. The flat portion may have irregularities with a maximum height of, for example, one-fifth or less of the height of the protrusions 31b. Flat portion 31a may further have a maximum height of, for example, 3 μm or less. Top portion 31c may have a curved surface that protrudes toward element portion 3 or toward the opposite side from element portion 3. When top portion 31c has a curved surface, the curved surface may have a height that is, for example, one-fifth or more of the height of protrusion 31b.

[0046] Furthermore, a flow path 40 through which an oxygen-containing gas flows is formed in the space formed between the flat portion 31a and the element portion 3. The oxygen-containing gas flows from the first end 41 side toward the second end 42 side shown in FIG. 1C so as to avoid the plurality of protrusions 31b. That is, in the flow path 40 through which the oxygen-containing gas as the first gas flows, the first end 41 corresponds to an inlet through which the oxygen-containing gas is supplied, and the second end 42 corresponds to an outlet through which the oxygen-containing gas is discharged. In this embodiment, the Z-axis direction from the first end 41 side toward the second end 42 side is defined as a first direction in which the oxygen-containing gas flows.

[0047] The width d of the flow path 40 located between the flat portion 31a and the element unit 3 can be, for example, 0.1 mm to 10 mm, or even 0.3 mm to 3.5 mm. Furthermore, in the region of the first portion 311 having the convex portions 31b in a planar view, the area ratio of the convex portions 31b can be, for example, 1% to 60%, or even 3% to 45%. By setting the area ratio of the convex portions 31b to 1% or more, the flat portion 31a is less likely to come into contact with the element unit 3, thereby maintaining the structure of the flow path 40. By setting the area ratio of the convex portions 31b to 60% or less, the oxygen-containing gas can flow without stagnation from the supply port to the discharge port, and the oxygen-containing gas necessary for power generation can be supplied to the air electrode 8 of the element unit 3.

[0048] The region of the first portion 311 having the convex portions 31b is, for example, a region R1 shown in FIG. 1C , which includes multiple convex portions 31b within the region and whose outline is in contact with the convex portion 31b located at the outermost periphery. The shape of the region having the convex portions 31b may be, for example, a shape in which the perimeter of a polygon formed by connecting the outlines of all the convex portions 31b located within the region is minimized. By arranging such a flow path member 30, the power generation performance of the cell 1 is further improved. Note that the multiple convex portions 31b may have convex portions 31b whose tops 31c are spaced apart from the element portion 3.

[0049] 1C , when the surface 31 of the flow path member 30 is viewed in plan from the element section 3 side (the Y-axis positive direction side), the line segment connecting the first end 41 and the second end 42 intersects with at least one of the plurality of convex portions 31 b. For example, the line segment S1 intersects with the convex portion 31 b located in the region 33 close to the first end 41. The line segment S2 does not intersect with the convex portion 31 b located in the region 33, but intersects with the convex portion 31 b located in the region 34. In other words, when the flow path member 30 is viewed from the first end 41 side, the plurality of convex portions 31 b are positioned without any gaps in the flow path 40, as shown in FIG.

[0050] In the cell 1 having such a flow path member 30, the oxygen-containing gas flowing through the flow path 40 collides with at least one convex portion 31b between the first end 41 and the second end 42, and branches in multiple directions. The branched oxygen-containing gas merges at the flat portion 31a with oxygen-containing gas that has branched upon collision with other convex portions 31b. By branching and merging the oxygen-containing gas in this manner, for example, oxygen-containing gases of different temperatures are mixed. As a result, in the cell 1 having the flow path member 30, the thermal uniformity of the element portion 3 and / or the oxygen-containing gas via the flow path member 30 can be improved compared to when the oxygen-containing gas travels straight from the first end 41 to the second end 42, and the power generation performance of the cell 1 is improved.

[0051] The flat portion 31a of the first portion 311 and the second portion 312 may be at different distances from the air electrode 8. The surface 31 located in the second portion 312 may be located, for example, farther from the flat portion 31a than the air electrode 8. The surface 31 may have an intermediate portion located between the first portion 311 and the second portion 312.

[0052] The element unit 3 may be positioned so as to face the entire surface of the first portion 311. This can improve the thermal uniformity of the element unit 3 and / or the oxygen-containing gas, thereby improving the power generation performance of the cell 1. Note that the second portion 312 may have, for example, a portion that does not face the element unit 3. That is, the surface 31 of the flow path member 30 may have, for example, a portion that does not face the element unit 3.

[0053] 2B , the plurality of protrusions 31 b may include two or more first protrusions 31 b 1 and two or more second protrusions 31 b 2. The first protrusions 31 b 1 are protrusions 31 b that are arranged at a distance from each other in a second direction different from the first direction (Z-axis direction) when viewed in a plan view from the element portion 3 side.

[0054] The first convex portion 31b1 may have a portion extending in a direction different from the first direction. The first convex portion 31b1 may have a portion extending in a second direction. The first convex portion 31b1 may have a length L1 in the second direction. This improves the rigidity of the flow path member 30, and further improves the performance of the cell 1.

[0055] In addition, the second convex portions 31b2 are convex portions 31b that are positioned between adjacent first convex portions 31b1 in the second direction, spaced apart from the first convex portions 31b1, and are arranged spaced apart from each other in a third direction that is different from the first and second directions.

[0056] The second protrusions 31b2 may have a portion extending in a direction different from the first direction. The second protrusions 31b2 may have a portion extending in a third direction. This improves the rigidity of the flow path member 30, and further improves the performance of the cell 1.

[0057] Furthermore, the multiple protrusions 31b may be arranged such that the angle between the second direction and / or the third direction and the first direction is 30° or more and 60° or less. For example, the first protrusions 31b1 may be arranged such that the angle between the second direction and the first direction is 30° or more and 60° or less. The second protrusions 31b2 may be arranged such that the angle between the third direction and the first direction is 30° or more and 60° or less. This improves the rigidity of the flow path member 30, further improving the performance of the cell 1.

[0058] Furthermore, when viewed from above from the element unit 3 side, the maximum Feret diameter of adjacent convex portions 31b may be greater than the distance between the geometric centers of adjacent convex portions 31b. This increases the area of ​​contact between the convex portions 31b and the oxygen-containing gas, promoting heat exchange between the flow path member 30 and the oxygen-containing gas. This can improve the thermal uniformity of the element unit 3 and / or the oxygen-containing gas, further improving the performance of the cell 1.

[0059] Furthermore, when the width of the flat portion 31a in the first direction (Z-axis direction) where the plurality of protrusions 31b are located is defined as length L0 (see FIG. 1C ), and the largest of the maximum Feret diameters of the plurality of protrusions 31b is defined as length L1, L1≦1 / 5×L0 may be satisfied. This can improve the thermal uniformity of the element portion 3 and improve the power generation performance of the cell 1. Here, the maximum Feret diameter of the protrusions 31b refers to the maximum length of the line segment connecting two points on the contour of the protrusions 31b connected to the flat portion 31a.

[0060] Furthermore, when the distance between the geometric centers of adjacent convex portions 31b along the first direction (Z-axis direction) is defined as length L2, L2≦3×L1 may be satisfied. This lengthens the path that the oxygen-containing gas flowing through the flow path 40 takes from the first end 41 to the second end 42, thereby promoting heat exchange between the flow path member 30 and the oxygen-containing gas. This improves the thermal uniformity of the element portion 3 and / or the oxygen-containing gas via the flow path member 30, further improving the performance of the cell 1.

[0061] Furthermore, when the distance between the geometric centers of adjacent convex portions 31b along the X-axis direction intersecting the first direction (Z-axis direction) is defined as length L3, L3≦3×L1 may be satisfied. This lengthens the path that the oxygen-containing gas flowing through the flow path 40 takes from the first end 41 to the second end 42, thereby promoting heat exchange between the flow path member 30 and the oxygen-containing gas. This can improve the thermal uniformity of the element unit 3 and / or the oxygen-containing gas via the flow path member 30, further improving the performance of the cell 1.

[0062] Furthermore, when the distance between the geometric centers of adjacent convex portions 31b in the second direction and / or the third direction is defined as length L4, L4≦2×L1 may be satisfied. This lengthens the path that the oxygen-containing gas flowing through the flow path 40 takes from the first end 41 to the second end 42, thereby promoting heat exchange between the flow path member 30 and the oxygen-containing gas. This improves the thermal uniformity of the element portion 3 and / or the oxygen-containing gas via the flow path member 30, further improving the performance of the cell 1.

[0063] 2B, two or more first protrusions 31b1 positioned side by side in the second direction are arranged so as to be positioned on a straight line extending in the second direction, but this is not limited to this. For example, when two or more first protrusions 31b1 are positioned on two or more straight lines extending parallel to the second direction, they are also defined as being positioned side by side in the second direction.

[0064] <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 3A to 3C. Figure 3A is a perspective view showing an example of an electrochemical cell device according to the first embodiment. Figure 3B is a cross-sectional view taken along line X-X shown in Figure 3A. Figure 3C is a top view showing an example of an electrochemical cell device according to the first embodiment.

[0065] As shown in FIG. 3A, the cell stack device 10 includes 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.

[0066] The fixing member 12 has a fixing material 13 and a support member 14. The support member 14 supports the cell 1. The fixing material 13 fixes the cell 1 to the support member 14. The support member 14 also has a support 15 and a gas tank 16. The support 15 and the gas tank 16, which are the support member 14, are made of metal and are electrically conductive.

[0067] 3B, 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.

[0068] 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.

[0069] In the example shown in Fig. 3A, fuel gas is stored in an internal space 22 (see Fig. 3B) formed by a support body 15, which is the support member 14, and a gas tank 16. A gas circulation pipe 20 is connected to the gas tank 16. The fuel gas is supplied to the gas tank 16 through this gas circulation pipe 20, and is supplied from the gas tank 16 to a flow path 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.

[0070] 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.

[0071] The example shown in Fig. 3A includes two rows of cell stacks 11, two supports 15, and a gas tank 16. Each of the two rows of cell stacks 11 has a plurality of cells 1. Each cell stack 11 is fixed to a corresponding support 15. The gas tank 16 has two through-holes on its top surface. A support 15 is disposed in each through-hole. An internal space 22 is formed by the one gas tank 16 and the two supports 15.

[0072] The shape of the insertion hole 15a is, for example, an oval shape when viewed from above. For example, the length of the insertion hole 15a in the arrangement direction of the cells 1, i.e., the thickness direction T, is greater than the distance between the two end current collecting members 17 located at both ends of the cell stack 11. For example, the width of the insertion hole 15a is greater than the length of the cell 1 in the width direction (X-axis direction: see FIG. 1A ).

[0073] 3B, the joints between the inner walls of the insertion holes 15a and the lower ends of the cells 1 are filled with and solidified with fixing material 13. This bonds and fixes the inner walls of the insertion holes 15a to the lower ends of the multiple cells 1, respectively, and also bonds and fixes the lower ends of the cells 1 to each other. The flow paths 2a of each cell 1 communicate with the internal space 22 of the support member 14 at their lower ends.

[0074] 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.

[0075] 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 system, 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.

[0076] 3B , a conductive member 18 is interposed between adjacent cells 1 among the plurality of cells 1. The conductive member 18 electrically connects one adjacent cell 1 to the other adjacent cell 1 in series. More specifically, the conductive member 18 connects the fuel electrode 5 of one cell 1 to the air electrode 8 of the other cell 1.

[0077] 3B, 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. 3A.

[0078] 3C, the cell stack device 10 may be a single battery in which two cell stacks 11A, 11B are connected in series. In such a case, the conductive portion 19 of the cell stack device 10 may have a positive terminal 19A, a negative terminal 19B, and a connection terminal 19C.

[0079] 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.

[0080] 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.

[0081] <Module> Next, a module according to an embodiment of the present disclosure using the above-described cell stack device 10 will be described with reference to Fig. 4. Fig. 4 is an external perspective view showing an example of a 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 removed to the rear.

[0082] 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.

[0083] 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.

[0084] The fuel gas produced in the reformer 102 is supplied to the flow path 2 a of the cell 1 (see FIG. 1A) through the gas distribution pipe 20 , the gas tank 16 , and the support member 14 .

[0085] 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.

[0086] In such a module 100, as described above, by accommodating the cell stack device 10 that improves power generation performance, the module 100 can be made to have improved power generation performance.

[0087] <Module Enclosure Device> Fig. 5 is an exploded perspective view schematically illustrating an example of a module enclosure device according to the first embodiment. The module enclosure device 110 according to this embodiment includes an outer case 111, the module 100 shown in Fig. 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.

[0088] 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.

[0089] 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.

[0090] In such a module accommodating device 110, as described above, by providing the module 100 with improved power generation performance in the module accommodating chamber 115, the module accommodating device 110 can be made to have improved power generation performance.

[0091] 6A to 6C are plan views showing examples of convex portions of a flow path member. To simplify the illustration, each of FIGS. 6A to 6C shows two first convex portions 31b1 aligned along the X-axis.

[0092] As shown in Figures 6A to 6C, the first convex portion 31b1, when viewed in plan from the element portion 3 side (the Y-axis positive direction side), may be elliptical (see Figure 6A), rectangular (see Figure 6B), or oval with semicircles joined to both ends of a rectangle (see Figure 6C). The distance L5 between adjacent first convex portions 31b1 in the second direction may be, for example, 0.1 mm or more. The distance L5 may be any distance that allows the oxygen-containing gas to flow smoothly from the supply port to the exhaust port. Note that the second convex portion 31b2 is not shown in Figures 6A to 6C.

[0093] 6A to 6C may be applied to the second protrusion 31b2 (see FIG. 2A). In such a case, the shapes of the first protrusion 31b1 and the second protrusion 31b2 may be the same or different.

[0094] 7A to 7E are plan views showing other examples of convex portions that the flow path member has.

[0095] 7A , the plurality of protrusions 31b may have protrusions 31b3 that are Λ-shaped (V-shaped) when viewed in a plan view from the element unit 3 side (positive Y-axis direction). The plurality of protrusions 31b may also have protrusions 31b4 that are crescent-shaped when viewed in a plan view from the element unit 3 side. The plurality of protrusions 31b may also have protrusions 31b5 that are Y-shaped when viewed in a plan view from the element unit 3 side. The plurality of protrusions 31b may also have protrusions 31b6 that are X-shaped when viewed in a plan view from the element unit 3 side.

[0096] Furthermore, the multiple convex portions 31b may have a polygonal shape when viewed in a plan view from the element portion 3 side. For example, as shown in FIG. 7B , the multiple convex portions 31b may have a convex portion 31b7 that has a triangular shape when viewed in a plan view from the element portion 3 side. The multiple convex portions 31b may also have a convex portion 31b8 that has a square shape when viewed in a plan view from the element portion 3 side. The multiple convex portions 31b may also have a convex portion 31b9 that has a hexagonal shape when viewed in a plan view from the element portion 3 side. Note that each side of the polygon may be a straight line or may include a curved line. Furthermore, each surface of the convex portion 31b may be a flat surface or may include a curved surface.

[0097] Furthermore, the convex portions 31b7 to 31b9 may have an apex 31c in the central portion when viewed in plan from the element portion 3 side. Such apex 31c may be a second flat portion. As shown in FIG. 7C , the convex portion 31b may include convex portions 31b7 to 31b9 that are located inside the outline of the convex portion where the outline of the apex 31c, which is the second flat portion, intersects with the flat portion 31a, which is the first flat portion, when viewed in plan from the element portion 3 side. The convex portions 31b7 to 31b9 may have a recess 31d in the central portion.

[0098] 7D, the plurality of protrusions 31b may include a circular protrusion 31bA or a trapezoidal protrusion 31bB when viewed from the element unit 3 side (positive Y-axis direction). The protrusions 31bA and 31bB may have an apex 31c in the center when viewed from the element unit 3 side. The apex 31c may be a second flat portion. As shown in FIG. 7E, the protrusions 31b may include protrusions 31bA and 31bB that are located inside the contour of the protrusion where the contour of the apex 31c, which is the second flat portion, intersects with the flat portion 31a, which is the first flat portion, when viewed from the element unit 3 side. The protrusions 31bA and 31bB may have a recess 31d in the center.

[0099] The plurality of protrusions 31b may include one or more of the protrusions 31b3 to 31bB described above. Note that the shapes of the protrusions 31b3 to 31bB shown in Figures 7A to 7E are merely examples, and for example, the protrusions 31b3 to 31bB may have a shape rotated around the Y axis. In this case, the protrusions 31b may include protrusions 31b3 to 31bB having portions extending in the second direction and / or the third direction.

[0100] The above describes an example in which the flow path member 30 has a plurality of protrusions 31b protruding toward the air electrode 8 of the element section 3, but the plurality of protrusions 31b may also protrude toward the support member 2. Furthermore, the flow path member 30 having a plurality of protrusions 31b protruding toward the air electrode 8 and / or the fuel electrode 5 may also be used as an interconnector for a flat cell that does not have a support member 2. Furthermore, the protrusions 31b may have an inclined side surface connecting the flat portion 31a and the top portion 31c.

[0101] [Second Embodiment] Fig. 8A is a perspective view showing an example of an electrochemical cell device according to a second embodiment. Fig. 8B is a partial cross-sectional view of the electrochemical cell device shown in Fig. 8A. Fig. 8C is a partial cross-sectional view of a region R2 shown in Fig. 8B.

[0102] 8A and 8B , the cell stack device 10 has a plurality of cells 1 arranged (stacked) in the thickness direction of the cells 1. Each cell 1 has an element section 3 in which an anode 5, a solid electrolyte layer 6, and an air electrode 8 are stacked, a flow path member 30, and a conductive member 92. In an electrochemical cell device in which a plurality of flat cells are stacked, for example, the plurality of cells 1 are electrically connected by adjacent flow path members 30 and conductive members 92. The flow path member 30 and conductive member 92 electrically connect adjacent cells 1 to each other and also have a gas flow path that supplies gas to the anode 5 or the air electrode 8.

[0103] 8B , the cell 1 has a sealing material that airtightly seals the fuel gas flow path 98 and the oxygen-containing gas flow path 97 of the flat cell stack. The sealing material is a fixing member 96 for the cell 1, and has a bonding material 93 and support members 94 and 95 that serve as a frame. The bonding material 93 may be glass or a metal material such as silver solder.

[0104] The support member 94 may be a so-called separator that separates the flow paths 97 and 98. The material of the support members 94 and 95 may be, for example, a conductive metal or an insulating ceramic. Either or both of the support members 94 and 95 may be made of an insulating material. If the support member 94 is made of metal, the support member 94 may be integrated with the conductive member 92. If the support member 95 is made of metal, the support member 95 may be integrated with the conductive member 91.

[0105] One of the support members 94 and 95 is insulating, and electrically insulates the two conductive members 91 and 92 that sandwich the flat cell from each other.

[0106] The flow path member 30 has a first portion 311 facing the element unit 3. As shown in FIG. 8C , the first portion 311 has a flat portion 31a as a first flat portion and multiple convex portions 31b. The flat portion 31a is positioned to face the element unit 3. The flow path member 30 has a supply port located at a first end, which is one end in a first direction in which the first gas flows (for example, the depth direction of the page), and a discharge port located at a second end, which is the other end in the first direction. When viewed in plan from the element unit 3 side, a line connecting the first end and the second end of the flow path member 30 intersects with at least one of the multiple convex portions 31b. That is, when the flow path member 30 is viewed from the first end side, as shown in FIG. 8C , multiple convex portions 31b are positioned without gaps in the flow path 40.

[0107] In the cell 1 having such a flow path member 30, the oxygen-containing gas flowing through the flow path 40 collides with at least one of the protrusions 31b on the way from the first end to the second end, and branches off in multiple directions. Therefore, compared to when the oxygen-containing gas flows straight through the flow path 40 from the first end to the second end, the thermal uniformity of the element portion 3 and / or the oxygen gas via the flow path member 30 can be improved, and the power generation performance of the cell 1 is improved.

[0108] Other Embodiments In the above-described embodiments, a fuel cell, a fuel cell stack device, a fuel cell module, and a fuel cell device are shown as examples of an "electrochemical cell," "electrochemical cell device," "module," and "module housing device." However, other examples may be an electrolysis cell, an electrolysis cell stack device, an electrolysis module, and an electrolysis device, respectively. The electrolysis 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 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, an electrolysis cell stack device, an electrolysis module, and an electrolysis device can improve electrolysis performance.

[0109] The present disclosure has been described in detail above, but 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.

[0110] In one embodiment, (1) an electrochemical cell includes an element portion and a flow path member having a first flat portion facing the element portion and a plurality of convex portions protruding from the first flat portion toward the element portion, wherein the flow path member has a supply port located at a first end in a first direction in which a first gas flows and a discharge port located at a second end opposite to the first end in the first direction, and when viewed in a plan view from the element portion side, a line segment connecting the first end and the second end intersects with at least one of the plurality of convex portions.

[0111] (2) In the electrochemical cell of (1) above, when viewed in a plan view from the element portion side, the plurality of protrusions may have: two or more first protrusions arranged at a distance from each other in a second direction different from the first direction; and two or more second protrusions arranged at a distance from each other in a third direction different from the first direction and the second direction, the second protrusions being located between the first protrusions adjacent to each other in the second direction and spaced apart from the first protrusions.

[0112] (3) In the electrochemical cell of (2) above, the first convex portion and the second convex portion may have a portion extending in a direction different from the first direction.

[0113] (4) In the electrochemical cell of (2) or (3) above, the first protrusion may have a portion extending in the second direction.

[0114] (5) In the electrochemical cell of any one of (2) to (4) above, the second protrusion may have a portion extending in the third direction.

[0115] (6) In the electrochemical cell of any one of (2) to (5) above, the angle formed between the second direction and / or the third direction and the first direction may be 30° or more and 60° or less.

[0116] (7) In the electrochemical cell of any one of (1) to (6) above, when viewed in a plan view from the element portion side, the maximum Feret diameters of the adjacent protrusions may each be larger than the distance between the geometric centers of the adjacent protrusions.

[0117] (8) In the electrochemical cell of any one of (1) to (7) above, the plurality of protrusions may include a protrusion having a second flat portion at an apex facing the element portion.

[0118] (9) In the electrochemical cell of (8) above, when viewed in a plan view from the element portion side, the plurality of convex portions may include a convex portion located inside the outline of the convex portion where the outline of the second flat portion intersects with the first flat portion.

[0119] In one embodiment, (10) an electrochemical cell device has a cell stack including any one of the electrochemical cells (1) to (9) above.

[0120] In one embodiment, (11) a module includes the electrochemical cell device of (10) above, and a container that houses the electrochemical cell device.

[0121] In one embodiment, (12) a module housing device includes: the module of (11); an auxiliary device for operating the module; and an exterior case for housing the module and the auxiliary device.

[0122] 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.

[0123] REFERENCE SIGNS LIST 1 cell 2 support member 3 element portion 5 fuel electrode 6 solid electrolyte layer 8 air electrode 10 cell stack device 30 flow path member 31a flat portion 31b protruding portion 100 module 110 module receiving device

Claims

1. An electrochemical cell comprising: an element portion; and a flow path member having a first flat portion facing the element portion and a plurality of convex portions protruding from the first flat portion toward the element portion, wherein the flow path member has a supply port located at a first end in a first direction in which a first gas flows, and a discharge port located at a second end opposite the first end in the first direction, wherein, when viewed in a plan view from the element portion side, a line segment connecting the first end and the second end intersects with at least one of the plurality of convex portions.

2. The electrochemical cell described in claim 1, wherein, when viewed in a plan view from the element portion side, the multiple convex portions have: two or more first convex portions aligned at a distance from each other in a second direction different from the first direction; and two or more second convex portions aligned at a distance from each other in a third direction different from the first direction and the second direction, the second convex portions being located between the first convex portions adjacent to each other in the second direction and spaced apart from the first convex portions.

3. The electrochemical cell according to claim 2, wherein the first convex portion and the second convex portion have portions extending in a direction different from the first direction.

4. An electrochemical cell according to claim 2 or 3, wherein the first convex portion has a portion extending in the second direction.

5. An electrochemical cell according to any one of claims 2 to 4, wherein the second convex portion has a portion extending in the third direction.

6. An electrochemical cell according to any one of claims 2 to 5, wherein an angle between the second direction and / or the third direction and the first direction is equal to or greater than 30° and equal to or less than 60°.

7. An electrochemical cell according to any one of claims 1 to 6, wherein, when viewed in a plan view from the element portion side, the maximum Feret diameters of adjacent protrusions are each greater than the distance between the geometric centers of adjacent protrusions.

8. An electrochemical cell according to any one of claims 1 to 7, wherein the plurality of protrusions include a protrusion having a second flat portion at an apex facing the element portion.

9. An electrochemical cell as described in claim 8, wherein, when viewed in a plan view from the element portion side, the plurality of convex portions include a convex portion located inside an outline of the convex portion where the outline of the second flat portion intersects with the first flat portion.

10. An electrochemical cell device comprising a cell stack comprising the electrochemical cell according to any one of claims 1 to 9.

11. A module comprising: the electrochemical cell device according to claim 10; and a container for housing the electrochemical cell device.

12. A module housing device comprising: a module according to claim 11; an auxiliary device for operating said module; and an exterior case for housing said module and said auxiliary device.

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