Electrochemical cell, solid oxide fuel cell, solid oxide electrolysis cell, and method for manufacturing electrochemical cell

Abstract

The present invention comprises: a cell main body part in which a first electrode layer, an electrolyte layer, and a second electrode layer are stacked in this order; and a metal support body which supports the cell main body part. The metal support body comprises a support part which comprises a support surface that supports the first electrode layer-side main surface of the cell main body part, and an opposite surface on the reverse side of the support surface, and which can communicate a gas between the support surface and the opposite surface. An adhesive layer that is bonded to the support surface is disposed in a facing region of the support surface, the facing region facing the peripheral edge part of the first electrode layer. The region of the first electrode layer positioned inside the peripheral edge part is bonded to the support surface, and the peripheral edge part of the first electrode layer is bonded to the adhesive layer.

Description

Electrochemical cell, solid oxide fuel cell, solid oxide electrolysis cell, and method for manufacturing electrochemical cell

[0001] The present invention relates to an electrochemical cell, a solid oxide fuel cell, a solid oxide electrolysis cell, and a method for manufacturing an electrochemical cell.

[0002] JP6800297B discloses an electrochemical cell in which an electrode layer material and an electrolyte layer material are laminated in this order on a metal support having a plurality of through holes, and then fired to laminate the electrode layer and the electrolyte layer on the metal support.

[0003] However, in the structure of JP6800297B, peeling occurs at the interface between the metal support and the electrode layer during firing, making it difficult to integrate the metal support and the electrode layer.

[0004] Therefore, an object of the present invention is to provide an electrochemical cell, a solid oxide fuel cell, a solid oxide electrolysis cell, and a method for manufacturing an electrochemical cell that reduce peeling between a metal support and an electrode layer when the material of the electrode layer disposed on the metal support is fired.

[0005] According to one aspect of the present invention, a cell includes a cell main body portion in which a first electrode layer, an electrolyte layer, and a second electrode layer are stacked in this order, and a metal support supporting the cell main body portion, the metal support including a support surface supporting the main surface of the cell main body portion on the side of the first electrode layer, and an opposite surface of the support surface, and a support portion that allows gas to communicate between the support surface and the opposite surface, an adhesive layer that adheres to the support surface is arranged in an opposing region of the support surface that faces the peripheral edge of the first electrode layer, the inside of the peripheral edge of the first electrode layer is adhered to the support surface, and the peripheral edge of the first electrode layer is adhered to the adhesive layer.

[0006] FIG. 1 is a cross-sectional view of an electrochemical cell of the first embodiment. FIG. 2 is a plan view of a metal support constituting the electrochemical cell of the first embodiment. FIG. 3 is a diagram showing the adhesion state between the anode support layer, the adhesive layer, and the support. FIG. 4 is a flow diagram showing the manufacturing process of the electrochemical cell of the first embodiment. FIG. 5 is a diagram showing the adjacent region of the anode support layer adjacent to the adhesive layer and the region other than the adjacent region of the anode support layer in the electrochemical cell after firing. FIG. 6 is a cross-sectional view of an electrochemical cell of a first comparative example. FIG. 7 is a cross-sectional view of an electrochemical cell of a second comparative example. FIG. 8 is a cross-sectional view of an electrochemical cell of the second embodiment. FIG. 9 is a schematic diagram of the electrochemical cell of this embodiment when used as a solid oxide electrolysis cell.

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0008] [First embodiment] Fig. 1 is a cross-sectional view of an electrochemical cell of the first embodiment. Fig. 2 is a plan view of a metal support 1 constituting the electrochemical cell of the first embodiment. The electrochemical cell of the first embodiment is composed of the metal support 1 and a cell main body 6 (anode support layer 2 (first electrode layer), anode active layer 3 (first electrode layer), electrolyte layer 4, and air cathode layer 5 (second electrode layer)).

[0009] The cell body 6 (electrolyte layer 4) is a ２－ In the first embodiment, the cell body 6 functions as a solid oxide fuel cell that generates electricity by supplying an anode gas (hydrogen gas) to the first electrode layer (anode support layer 2, anode active layer 3) and a cathode gas (air, oxygen) to the second electrode layer (air cathode layer 5).

[0010] The metal support 1 has a plate shape with a predetermined thickness. For example, the metal support 1 has a rectangular shape in plan view as shown in Fig. 2, but may have other shapes. A plurality of through holes 123 are formed in the metal support 1, and the region where the through holes 123 are formed becomes the support portion 12, and the portion on the outer periphery of the support portion becomes the outer periphery portion 13.

[0011] The through holes 123 have a cross-sectional shape that is, for example, circular, and communicate with the support surface 121 and the opposite surface thereof, the gas flow surface 122. The arrangement pattern of the through holes 123 can be set arbitrarily, but it is preferable to arrange them so that they are distributed approximately uniformly in the support part 12 in a plan view.

[0012] The through-holes 123 can be formed by mechanical processing (for example, punching), laser processing, or chemical processing (for example, etching), but in this embodiment, they are preferably formed by a fiber laser.

[0013] The through holes 123 allow gas to pass between the support surface 121 and the flow surface 122. However, instead of forming the through holes 123, the metal support 1 may be made of a porous metal to be permeable to gas, thereby supplying gas to the anode support layer 2 and the anode active layer 3.

[0014] The diameter of the through-hole 123 is preferably 100 μm to 500 μm, and the thickness of the metal support 1 (support portion 12) is preferably 50 μm to 500 μm.

[0015] The metal support 1 (support portion 12) is preferably made of Fe-Cr alloy steel (for example, stainless steel such as SUS304), but Ni-Cr alloy steel or the like can also be used. ２ ) and Al (Al ２ O ３ ) may be contained.

[0016] An adhesive layer 7 is disposed on the peripheral edge and outer periphery 13 of the support surface 121 of the support portion 12 so as to surround (go around) the inside of the peripheral edge and outer periphery 13. The adhesive layer 7 adheres to the anode support layer 2 and the electrolyte layer 4, thereby fixing the anode support layer 2 and the electrolyte layer 4 to the metal support 1.

[0017] The adhesive layer 7 is preferably disposed at a position on the support portion 12 (support surface 121) that is more outer than the through-holes 123. As shown in Fig. 2 , in the metal support 1, a rectangular ring-shaped region sandwiched between the inner periphery of the adhesive layer 7 and a rectangular dashed line indicating the boundary between the support portion 12 and the outer periphery 13 is a facing region that faces (adheres to) the peripheral edge of the anode support layer 2 in the support portion 12, and the rectangular ring-shaped region sandwiched between the dashed line and the outer periphery of the adhesive layer 7 is a region that adheres to the electrolyte layer 4 in the outer periphery 13.

[0018] The material constituting the adhesive layer 7 contains cerium oxide. Cerium oxide is more likely to interdiffuse with the stainless steel constituting the metal support 1 than, for example, zirconia constituting the electrolyte layer 4. Therefore, the inclusion of cerium oxide in the adhesive layer 7 improves the adhesive strength (peel strength) between the adhesive layer 7 and the support portion 12 (support surface 121) of the metal support 1. There are no particular restrictions on the thickness of the adhesive layer 7, but it can be, for example, 1 μm to 2 μm.

[0019] The fuel electrode support layer 2 (fuel electrode layer) is supported by a support portion 12 formed on the metal support 1, and is disposed on a support surface 121 of the support portion 12. The peripheral edge of the fuel electrode support layer 2 is disposed on the upper surface of the adhesive layer 7.

[0020] The fuel electrode support layer 2 communicates with the flow surface 122 side of the support portion 12 via the through-holes 123 .

[0021] The anode support layer 2 is preferably porous. The porosity (100% - filling rate) of the anode support layer 2 is not particularly limited, but may be, for example, 20% to 70%. The thickness of the anode support layer 2 is not particularly limited as long as it is thicker than the thickness of the adhesive layer 7, but may be, for example, 2 μm to 100 μm.

[0022] In the first embodiment, an anode gas (for example, hydrogen gas) is supplied to the fuel electrode support layer 2, and the fuel electrode support layer 2 functions as the anode of the solid oxide fuel cell.

[0023] The fuel electrode support layer 2 is made of NiO-GDC (gadolinium-doped ceria), Ni-GDC, NiO-YSZ (yttria-stabilized zirconia), Ni-YSZ, or CuO-CeO ２ , Cu—CeO ２ It can be made of composite materials such as:

[0024] The method for forming the fuel electrode support layer 2 is not particularly limited, and the layer can be formed by a screen printing method, a press molding method, a tape casting method, a firing method, a spray coating method (such as a thermal spraying method, an aerosol deposition method, an aerosol gas deposition method, a powder jet deposition method, a particle jet deposition method, or a cold spray method), a PVD method (such as a sputtering method or a pulsed laser deposition method), or a CVD method.

[0025] The anode active layer 3 is disposed on the anode support layer 2. There are no particular restrictions on the thickness of the anode active layer 3, but it can be, for example, 1 μm to 100 μm.

[0026] The anode active layer 3 preferably has oxide ion (oxygen ion) conductivity. The anode active layer 3 more preferably has electron conductivity. The anode active layer 3 can be made of YSZ, GDC, SSZ (scandium-stabilized zirconia), SDC (samarium-doped ceria), or the like. There are no particular limitations on the method for forming the anode active layer 3, and it can be formed by screen printing, press molding, tape casting, firing, spray coating, PVD, CVD, or the like.

[0027] The electrolyte layer 4 is disposed on the anode active layer 3. The electrolyte layer 4 is disposed so as to cover at least the upper surface of the anode active layer 3. The electrolyte layer 4 is disposed so as to extend to a position overlapping the main surface of the outer periphery 13 in a plan view and to extend toward the adhesive layer 7 disposed on the outer periphery 13. The electrolyte layer 4 surrounds (goes around) the side surfaces of the anode active layer 3 and the anode support layer 2, and is disposed so as to cover and adhere to these side surfaces. The electrolyte layer 4 is also adhered to the upper surface of the portion of the adhesive layer 7 disposed on the main surface of the outer periphery 13, surrounding (going around) that portion.

[0028] As described above, the electrolyte layer 4 contains oxygen ions (O ２－ ) The electrolyte layer 4 has gas barrier properties sufficient to prevent mixing of the anode gas and the cathode gas. The electrolyte layer 4 may have a multi-layer structure, but it is preferable that at least one layer is a dense layer. The porosity of the dense layer is preferably 10% or less, more preferably 5% or less, and even more preferably 2% or less. The thickness of the electrolyte layer 4 is not particularly limited, but can be, for example, 1 μm to 10 μm.

[0029] The electrolyte layer 4 can be made of YSZ, GDC, SSZ, SDC, LSGM, etc. The method for forming the electrolyte layer 4 is not particularly limited, and the electrolyte layer 4 can be formed by a screen printing method, a press molding method, a firing method, a spray coating method, a PVD method, a CVD method, etc.

[0030] The cathode layer 5 is disposed on the electrolyte layer 4. The electrolyte layer 4 is thus sandwiched between the cathode layer 5 and the anode active layer 3.

[0031] The air electrode layer 5 is formed, for example, such that its outer shape in plan view is accommodated inside the outer shapes of the anode support layer 2 and the anode active layer 3. The adhesive layer 7 is disposed so as to be spaced apart from the region that overlaps with the air electrode layer 5 in plan view (the region used for the power generation reaction). In other words, the adhesive layer 7 is disposed so that the outer shape of the air electrode layer 5 is accommodated inside the inner periphery of the frame-shaped adhesive layer 7 in plan view.

[0032] This prevents the adhesive layer 7 from interfering with the power generation region between the air electrode layer 5 and the anode support layer 2 and the anode active layer 3, thereby preventing a decrease in power generation performance.

[0033] The air electrode layer 5 is preferably porous. The porosity of the air electrode layer 5 is not particularly limited, but may be, for example, 20% to 70%. The thickness of the air electrode layer 5 is not particularly limited, but may be, for example, 1 μm to 100 μm.

[0034] As described above, a cathode gas (air, oxygen) is supplied to the air electrode layer 5, and the air electrode layer 5 functions as a cathode of the solid oxide fuel cell. The air electrode layer 5 can be composed of LSCF, LSF, LSC, LNF, LSM, or the like. In particular, the air electrode layer 5 preferably contains a perovskite-type oxide containing two or more elements selected from the group consisting of La, Sr, Sm, Mn, Co, and Fe.

[0035] There are no particular limitations on the method for forming the air electrode layer 5, and it can be formed by screen printing, press molding, firing, spray coating, PVD, CVD, or the like.

[0036] [Adhesion State Between Anode Support Layer 2, Adhesive Layer 7, and Support 12] FIG. 3 is a diagram showing the adhesion state between the anode support layer 2, adhesive layer 7, and support 12. As shown in FIG.

[0037] 3, the surface (support surface 121) of support portion 12 (metal support 1) is a smooth stainless steel plate, whereas anode support layer 2 is a sintered body of first particles 21A, 21B, and 21C having particle diameters on the order of microns. Therefore, the adhesive strength is weak due to the small adhesive area (contact area) per unit area between support portion 12 (support surface 121) and anode support layer 2, and peeling is likely to occur, particularly starting from the peripheral edge of anode support layer 2 during firing.

[0038] On the other hand, because adhesive layer 7 is a sintered body of second particles 71A, 71B having particle diameters on the submicron order, it has a larger adhesive area per unit area with support portion 12 (support surface 121) and can obtain high adhesive strength compared to anode support layer 2. Furthermore, since the diameters of second particles 71A, etc. are smaller than those of first particles 21A, etc. (for example, 1 / 10 or less) as described above, they can enter between the multiple first particles 21A, etc. that make up anode support layer 2.

[0039] 3 , the adhesive layer 7 includes, for example, a plurality of second particles 71A arranged on the support portion 12 (support surface 121) and a plurality of second particles 71B arranged on the second particles 71A. The second particles 71A are in direct contact (adhered) with the support portion 12 (support surface 121), and a pair of adjacent second particles 71A are also in contact (adhered) with each other. The second particles 71B are in contact (adhered) with the second particles 71A, and a pair of adjacent second particles 71B are in contact (adhered) with each other.

[0040] As shown in FIG. 3 , the fuel electrode support layer 2 includes, for example, first particles 21C that are in contact with (adhered to) the support portion 12 (support surface 121) and are arranged at positions spaced apart from the second particles 71A and the second particles 71B, first particles 21B that are in contact with (adhered to) the support portion 12 (support surface 121) and are in contact with (adhered to) the second particles 71A and the second particles 71B that form the side surfaces of the adhesive layer 7, and first particles 21A that are arranged on the adhesive layer 7 and are in contact with (adhered to) the second particles 71B (and the second particles 71A).

[0041] The first particle 21C is adhered to the support portion 12 (support surface 121) only by contact with the support portion 12 (support surface 121).

[0042] First particle 21B adheres to support 12 (support surface 121) and is further fixed to support 12 via second particles 71A and 71B that form the side surfaces of adhesive layer 7. Therefore, the adhesive strength (peel strength) of first particle 21B to support 12 is higher than that of first particle 21C.

[0043] The first particles 21A are separated from the support portion 12 (they may be in contact (adhered) with the support portion 12), but are fixed to the metal support 1 via the second particles 71A and 71B. The number of first particles 21C in contact (adhered) with the second particles 71A and 71B is greater than that of the first particles 21B, and the adhesion area of ​​the first particles 21C to the second particles 71A and 71B is greater than that of the first particles 21B. Therefore, the adhesion strength (peel strength) of the first particles 21A to the support portion 12 is higher than that of the first particles 21B.

[0044] Therefore, the peripheral edge of the anode support layer 2 is adhered to the adhesive layer 7 and fixed to the support 12 (support surface 121) via the adhesive layer 7, which reduces peeling of the anode support layer 2 from the support 12 (support surface 121) that starts from the peripheral edge of the anode support layer 2. The adhesive layer 7 may be disposed so as to continuously surround (complete a full circle) in the opposing region of the support 12 that faces the peripheral edge of the anode support layer 2, or may be disposed in a plurality of discrete positions at predetermined intervals so as to surround (complete a full circle) in the opposing region.

[0045] [Manufacturing Process of Electrochemical Cell] FIG. 4 is a flow diagram showing the manufacturing process of the electrochemical cell of the first embodiment.

[0046] As shown in FIG. 4, the manufacturing process of the electrochemical cell of this embodiment comprises steps S1 to S4.

[0047] In step S1, a plurality of through holes 123 are formed in the support portion 12 of the metal support body 1. The through holes 123 are formed, for example, by irradiating a fiber laser from the support surface 121 of the support portion 12 to engrave from the support surface 121 to the flow surface 122, or by performing a punching process using a press in which a punching member having an outer diameter equal to the inner diameter of the through holes 123 is passed from the support surface 121 to the flow surface 122.

[0048] In step S2, the adhesive layer 7, the anode support layer 2, the anode active layer 3, and the electrolyte layer 4 are laminated in this order on the support 12. Any method, such as screen printing, tape casting, or spray coating, can be used to form each layer. The adhesive layer 7 is arranged in a rectangular ring shape that covers the peripheral edge of the support surface 121 and the main surface of the outer periphery 13, an inner region adjacent to the support surface 121 ( FIG. 2 ). The anode support layer 2 and the anode active layer 3 are arranged on the support surface 121 so as to conform to the contour of the support surface 121. At this time, the peripheral edge of the anode support layer 2 is arranged so as to rest on the adhesive layer 7. The electrolyte layer 4 is arranged so as to cover the top surface of the anode active layer 3, to surround (completely encircle) the side surfaces of the anode active layer 3 and the anode support layer 2, and to surround (completely encircle) the portion of the adhesive layer 7 located at the outer periphery 13 and to connect (adhere) to that portion.

[0049] In step S3, the anode support layer 2, the anode active layer 3, and the electrolyte layer 4 are fired at a high temperature (1000°C to 1500°C) in an inert gas (nitrogen, argon) or reducing atmosphere (hydrogen gas atmosphere) to prevent deformation of the stainless steel due to high-temperature oxidation.

[0050] In step S4, the air electrode layer 5 is laminated on the electrolyte layer 4 by, for example, screen printing, and the air electrode layer 5 is solidified by heat treatment at a predetermined temperature.

[0051] In steps S2 and S3, the anode support layer 2 may be laminated on the support surface 121 and fired, the anode active layer 3 may be laminated on the fired anode support layer 2 and fired, and the electrolyte layer 4 may be laminated on the fired anode active layer 3 and fired. Alternatively, in steps S2 to S4, the anode support layer 2, the anode active layer 3, the electrolyte layer 4, and the air cathode layer 5 may be laminated in this order and then fired simultaneously.

[0052] [Anode Support Layer 2 After Firing] FIG. 5 is a diagram showing an adjacent region 22 of the anode support layer 2 adjacent to the adhesive layer 7 and a region of the anode support layer 2 other than the adjacent region 22 in the electrochemical cell after firing.

[0053] The shrinkage rate during sintering of the material (second particles 71A, etc. ( FIG. 3 )) constituting adhesive layer 7 is higher than the shrinkage rate during sintering of the material (first particles 21A, etc. ( FIG. 3 )) constituting anode support layer 2. Therefore, in adjacent region 22 of anode support layer 2 adjacent to adhesive layer 7, the spacing between particles (first particles 21A, etc. ( FIG. 3 )) becomes narrower as a result of shrinkage due to sintering of adhesive layer 7 than in other regions of anode support layer 2 other than adjacent region 22, resulting in a decrease in porosity (an increase in filling rate).

[0054] As shown in FIG. 5, the adjacent region 22 is formed to cover the upper and side surfaces of the adhesive layer 7 and further connects to the support surface 121 of the support portion 12 and the inner side surface of the electrolyte layer 4 .

[0055] Therefore, the adhesive area per unit area of ​​the peripheral portion of the anode support layer 2 to the adhesive layer 7, the adhesive area per unit area to the electrolyte layer 4, and the adhesive area per unit area to the support surface 121 increase, and the adhesive strength (peel strength) between the peripheral portion of the anode support layer 2 and the adhesive layer 7, the adhesive strength (peel strength) between the peripheral portion of the anode support layer 2 and the inner side surface of the electrolyte layer 4, and the adhesive strength (peel strength) between the peripheral portion of the anode support layer 2 and the adhesive layer 7 is higher than the adhesive strength (peel strength) between the peripheral portion of the anode support layer 2 and the inner side surface of the electrolyte layer 4 and the adhesive strength (peel strength) between the peripheral portion of the anode support layer 2 and the support surface 121.

[0056] Therefore, the sintered fuel electrode support layer 2 and adhesive layer 7 can efficiently reduce peeling from the support portion 12 starting from the peripheral edge portion (adjacent region 22) on the support portion 12 side.

[0057] Comparative Examples Fig. 6 is a cross-sectional view of an electrochemical cell of a first comparative example, and Fig. 7 is a cross-sectional view of an electrochemical cell of a second comparative example.

[0058] As shown in Fig. 6 , the first comparative example has a configuration in which adhesive layer 7 is omitted from the first embodiment. In this configuration, as described above, the adhesion area between first particles 21A, 21B (Fig. 3) constituting anode support layer 2 and support surface 121 is low at the peripheral edge and inside thereof of anode support layer 2. Therefore, in the first comparative example, it is difficult to reduce peeling of anode support layer 2 from support portion 12 (support surface 121) that originates from the peripheral edge of anode support layer 2.

[0059] 7 , in the second comparative example, an anode support layer 2 and an anode active layer 3 are laminated in this order on a support 12 (support surface 121), and then an adhesive layer 7 is laminated so as to cover the top surface of the anode active layer 3 and the side surfaces of the anode support layer 2 and the anode active layer 3 and to connect to the main surface of the outer periphery 13 of the metal support 1. An electrolyte layer 4 is then laminated so as to cover the top surface and side surfaces of the adhesive layer 7, and an air cathode layer 5 is laminated on the electrolyte layer 4.

[0060] In the second comparative example, it is conceivable that the adhesive strength to the support surface 121 of the side surface of the anode support layer 2 that comes into contact with the adhesive layer 7 after sintering will be improved in the same manner as described above. However, in the second comparative example, the peripheral portion of the anode support layer 2 is not disposed on the upper surface of the adhesive layer 7 as in the first embodiment, and the improvement in adhesive strength is therefore limited.

[0061] Furthermore, in the second comparative example, the adhesive layer 7 is disposed as a layer between the anode active layer 3 and the electrolyte layer 4, and the adhesive layer 7 exists as an ohmic resistor between the anode active layer 3 and the air cathode layer 5, resulting in a decrease in power generation efficiency.

[0062] However, in this embodiment, the anode support layer 2 is disposed such that its peripheral edge is placed on the adhesive layer 7 as described above ( FIG. 1 ). This results in the peripheral edge of the anode support layer 2 being firmly bonded to the adhesive layer 7, which is firmly bonded to the support 12 (support surface 121). This effectively reduces peeling of the anode support layer 2 from the support 12 (support surface 121) that starts from the peripheral edge of the anode support layer 2.

[0063] Furthermore, in this embodiment, the adhesive layer 7 is disposed so as to be separated from the area that overlaps with the air cathode layer 5 in a plan view (the area used for the power generation reaction), and therefore, a decrease in power generation efficiency can also be suppressed.

[0064] Second Embodiment FIG. 8 is a cross-sectional view of an electrochemical cell according to a second embodiment.

[0065] In the second embodiment, the portion of the electrolyte layer 4 that is bonded to the adhesive layer 7 extends so as to be further bonded to the side surface of the adhesive layer 7 and the upper surface of the outer periphery 13. This allows the electrolyte layer 4, which has a dense structure, to cover the adhesive layer 7 and the bonded position between the adhesive layer 7 and the outer periphery 13, thereby reducing gas leakage from the adhesive layer 7 or the interface between the adhesive layer 7 and the outer periphery 13.

[0066] In the second embodiment, a coating 111 (passive coating) of an oxide of at least one metal selected from Al (aluminum), Co (cobalt), Mn (manganese), Cu (copper), Zr (zirconium), Si (silicon), and Ce (cerium) is formed on the support surface 121 and the main surface of the outer peripheral portion 13 of the support portion 12 of the metal support 1. The coating 111 is formed by surface application using sputtering, spraying, plating, or the like. Arranging the adhesive layer 7 and the anode support layer 2 on this coating 111 improves the adhesive strength between the support portion 12 and the adhesive layer 7 and between the support portion 12 and the anode support layer 2. This reduces gas leakage at the interface between the support portion 12 (support surface 121) and the adhesive layer 7 and the interface between the support portion 12 (support surface 121) and the anode support layer 2, thereby improving yield.

[0067] In the second embodiment, when forming the stainless steel that is the material of the metal support 1, it is also possible to dope the stainless steel base material with at least one (one or more metals) of Al (aluminum), Co (cobalt), Mn (manganese), Cu (copper), Zr (zirconium), Si (silicon), and Ce (cerium), thereby forming a coating 111 (passive coating) of the doped material (oxide of the doped material) on the surface of the stainless steel. As described above, the electrochemical cell of the first embodiment is made of stainless steel, and a coating 111 (passive coating) of chromium oxide (not shown in FIG. 1 ) is formed on the surface of the stainless steel.

[0068] [Solid Oxide Electrolysis Cell] FIG. 9 is a schematic diagram of the electrochemical cell of this embodiment used as a solid oxide electrolysis cell.

[0069] The electrochemical cell of this embodiment can also be used as a solid oxide electrolysis cell. Fig. 9 shows a solid oxide electrolysis cell using the electrochemical cell of the first embodiment, but the electrochemical cell of the second embodiment can also be applied.

[0070] 9, water is supplied to the anode support layer 2 side, and a DC voltage is applied to the cell body, with the cathode layer 5 on the positive side of the DC voltage and the metal support 1 (anode support layer 2 and anode active layer 3) on the negative side of the DC voltage.

[0071] Water molecules (2H ２ O) reacts with hydrogen ions (4H ＋ ) and oxygen ions (2O ２－ )

[0072] Hydrogen ion (4H ＋ ) is converted into hydrogen molecules (2H) by the supply of electrons in the anode support layer 2 or the anode active layer 3. ２ )

[0073] Oxygen ions (2O ２－ ) is conducted through the electrolyte layer 4 to reach the air electrode layer 5, where electrons are taken away, resulting in oxygen molecules (O ２ )

[0074] [Effects of this embodiment] The electrochemical cell of this embodiment includes a cell body 6 in which a first electrode layer (anode support layer 2, anode active layer 3), an electrolyte layer 4, and a second electrode layer (air cathode layer 5) are laminated in this order, and a metal support 1 that supports the cell body 6. The metal support 1 includes a support surface 121 that supports the main surface of the cell body 6 on the side of the first electrode layer (anode support layer 2, anode active layer 3), and a surface opposite to the support surface 121 (flow surface 122). The gas passage is formed on the support surface 121 in a region facing the peripheral edge of the first electrode layer (anode support layer 2, anode active layer 3). An adhesive layer 7 is arranged on the support surface 121 in a region facing the peripheral edge of the first electrode layer (anode support layer 2, anode active layer 3). The inner side of the peripheral edge of the first electrode layer (anode support layer 2, anode active layer 3) is adhered to the support surface 121, and the peripheral edge of the first electrode layer (anode support layer 2, anode active layer 3) is adhered to the adhesive layer 7.

[0075] With the above configuration, the peripheral portion of the first electrode layer (fuel electrode support layer 2) is fixed to the support surface 121 via the adhesive layer 7, thereby reducing peeling of the first electrode layer (fuel electrode support layer 2) from the support portion 12 (support surface 121) that starts from the peripheral portion of the first electrode layer (fuel electrode support layer 2).

[0076] In this embodiment, the adhesive layer 7 is disposed so as to (continuously) surround (completely go around) the opposing region.

[0077] With the above-described configuration, the peripheral portion of the first electrode layer (fuel electrode support layer 2) can be adhered to the adhesive layer 7 without any omissions, and therefore peeling of the first electrode layer (fuel electrode support layer 2) from the support portion 12 (support surface 121) that starts from the peripheral portion of the first electrode layer (fuel electrode support layer 2) can be efficiently reduced.

[0078] In this embodiment, the support portion 12 has through holes 123 that allow gas to communicate between the support surface 121 and the opposite surface (flow surface 122).

[0079] With the above configuration, the support portion 12 can be constructed with a simple configuration.

[0080] In this embodiment, the particle diameter of the material (second particles 71A, etc.) that constitutes the adhesive layer 7 is smaller than the particle diameter of the material (first particles 21A, etc.) that constitutes the first electrode layer (fuel electrode support layer 2).

[0081] With the above configuration, the adhesive layer 7 has a larger adhesive area per unit area with the support 12 (support surface 121) than the first electrode layer (anode support layer 2), resulting in high adhesive strength. Furthermore, the peripheral portion of the first electrode layer (anode support layer 2) is fixed to the support 12 (support surface 121) via the adhesive layer 7, but multiple particles of the material (second particles 71A, etc.) constituting the adhesive layer 7 are embedded between the materials (first particles 21A, etc.) constituting the first electrode layer (anode support layer 2), supporting the materials (first particles 21A, etc.) constituting the first electrode layer (anode support layer 2). Therefore, the adhesive strength of the peripheral portion of the first electrode layer (anode support layer 2) to the adhesive layer 7 is stronger than the adhesive strength of the region inside the peripheral portion of the first electrode layer (anode support layer 2) to the support 12 (support surface 121). Therefore, the peripheral edge of the first electrode layer (fuel electrode support layer 2 ) can be firmly fixed to the support portion 12 (support surface 121 ) via the adhesive layer 7 .

[0082] In this embodiment, the metal support 1 further includes an outer periphery 13 that forms the outer periphery of the support portion 12, the adhesive layer 7 extends from the facing region to the outer periphery 13 and is disposed so as to (continuously) surround (go around) the outer periphery 13, and the electrolyte layer 4 surrounds (go around) the side surface of the first electrode layer (anode support layer 2, anode active layer 3), covering the side surface and adhering to the adhesive layer 7 disposed in the outer periphery 13 while (continuously) surrounding (going around) the adhesive layer 7.

[0083] With the above configuration, the dense electrolyte layer 4 can reduce gas leakage from the first electrode layer (anode support layer 2, anode active layer 3), the interface between the first electrode layer (anode support layer 2, anode active layer 3) and adhesive layer 7, and the interface between the electrolyte layer 4 and adhesive layer 7.

[0084] In this embodiment, the electrolyte layer 4 (completely) covers the adhesive layer 7 arranged in the outer peripheral portion 13 and (continuously) surrounds (circumvents) the outer region that is outside the electrolyte layer 4 of the outer peripheral portion 13, adhering to the outer region.

[0085] With the above-described configuration, the electrolyte layer 4 having a dense structure can reduce gas leakage from the adhesive layer 7 and the interface between the adhesive layer 7 and the outer peripheral portion 13 (metal support 1).

[0086] In this embodiment, the material constituting the adhesive layer 7 includes cerium oxide.

[0087] With the above-described configuration, interdiffusion is more likely to occur between the adhesive layer 7 and the stainless steel constituting the metal support 1 than between the adhesive layer 7 and the zirconia constituting the electrolyte layer 4. Therefore, by including cerium oxide in the adhesive layer 7, the adhesive strength (peel strength) between the adhesive layer 7 and the support portion 12 (support surface 121) of the metal support 1 can be improved.

[0088] In this embodiment, a coating 111 containing an oxide of at least one of aluminum, chromium, silicon, manganese, cobalt, and nickel is formed on the main surface of the metal support 1 on which the cell body portion 6 is disposed.

[0089] With the above configuration, when the adhesive layer 7 and the first electrode layer (fuel electrode support layer 2) are disposed on the coating 111, the adhesion between the support 12 and the adhesive layer 7 and the adhesion between the support 12 and the first electrode layer (fuel electrode support layer 2) are improved. This makes it possible to suppress gas leaks at the interface between the support 12 (support surface 121) and the adhesive layer 7 and the interface between the support 12 (support surface 121) and the fuel electrode support layer 2, thereby improving yield.

[0090] In this embodiment, the porosity of the adjacent region 22 of the first electrode layer (fuel electrode support layer 2) adjacent to the adhesive layer 7 is lower than the porosity of the region other than the adjacent region 22 of the first electrode layer (fuel electrode support layer 2).

[0091] In the above configuration, the shrinkage rate during sintering of the material (second particles 71A, etc. ( FIG. 3 )) constituting the adhesive layer 7 is higher than the shrinkage rate during sintering of the material (first particles 21A, etc. ( FIG. 3 )) constituting the first electrode layer (anode support layer 2). Therefore, in the adjacent region 22 of the first electrode layer (anode support layer 2) adjacent to the adhesive layer 7, the spacing between the particles (first particles 21A, etc. ( FIG. 3 )) becomes narrower as the adhesive layer 7 shrinks due to sintering than in other regions of the first electrode layer (anode support layer 2) other than the adjacent region 22, resulting in a decrease in porosity (an increase in packing factor). Therefore, with the above configuration, the adhesive area per unit area of ​​the first electrode layer (anode support layer 2) to the adhesive layer 7 increases, and the adhesive strength (peel strength) between the peripheral portion of the first electrode layer (anode support layer 2) and the adhesive layer 7 increases. Therefore, the first electrode layer (fuel electrode support layer 2) and adhesive layer 7 after sintering can efficiently reduce peeling from support portion 12 starting from the peripheral edge portion (adjacent region 22) on the support portion 12 side.

[0092] In this embodiment, the second electrode layer (air electrode layer 5) is disposed so that the outer shape of the second electrode layer (air electrode layer 5) is located more inward than the outer shapes of the first electrode layer (anode support layer 2, anode active layer 3) in a planar view, and the adhesive layer 7 is disposed so as to be spaced apart from the region overlapping with the second electrode layer (air electrode layer 5) in a planar view.

[0093] This configuration prevents the adhesive layer 7 from interfering with the power generation region between the air electrode layer 5 and the anode support layer 2 and anode active layer 3, thereby preventing a decrease in power generation performance.

[0094] The solid oxide fuel cell of this embodiment is a solid oxide fuel cell that uses the above-described electrochemical cell, in which the electrolyte layer 4 is made of an oxygen ion conductive oxide, and the cell main body 6 is capable of generating electricity by supplying a cathode gas (air, oxygen) to the second electrode layer (air cathode layer 5) and an anode gas (hydrogen) to the first electrode layer (anode support layer 2, anode active layer 3) via the support part 12.

[0095] With the above configuration, a solid oxide fuel cell can be constructed with a simple configuration.

[0096] The solid oxide electrolysis cell of this embodiment is a solid oxide electrolysis cell using the electrochemical cell described above, in which the electrolyte layer 4 is composed of an oxygen ion conductive oxide, and water is supplied to the first electrode layer (anode support layer 2, anode active layer 3) via the support part 12, and a voltage is applied between the first electrode layer (anode support layer 2, anode active layer 3) and the second electrode layer (air cathode layer 5), thereby enabling electrolysis of the water supplied to the first electrode layer (anode support layer 2, anode active layer 3).

[0097] With the above configuration, a solid oxide electrolysis cell can be constructed with a simple configuration.

[0098] The method for manufacturing an electrochemical cell of this embodiment involves laminating a first electrode layer (anode support layer 2, anode active layer 3), an electrolyte layer 4, and a second electrode layer (air cathode layer 5) in this order on a metal support 1, and the metal support 1 includes a support surface 121 that supports the first electrode layer (anode support layer 2, anode active layer 3) and a surface (flow surface 122) opposite to the support surface 121, and gas can be communicated between the support surface 121 and the surface (flow surface 122).The method involves laminating an adhesive layer 7 on the peripheral portion of the support surface 121, and laminating the first electrode layer (anode support layer 2, anode active layer 3) on the support surface 121, with the peripheral portion of the first electrode layer (anode support layer 2, anode active layer 3) being placed on the adhesive layer 7.

[0099] By using the above method, the peripheral portion of the first electrode layer (fuel electrode support layer 2) is fixed to the support surface 121 via the adhesive layer 7, and therefore peeling of the first electrode layer (fuel electrode support layer 2) from the support portion 12 (support surface 121) that starts from the peripheral portion of the first electrode layer (fuel electrode support layer 2) can be reduced.

[0100] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments.

Claims

1. An electrochemical cell comprising: a cell body portion formed by stacking a first electrode layer, an electrolyte layer, and a second electrode layer in this order; and a metal support supporting the cell body portion, wherein the metal support includes a support surface supporting the main surface of the cell body portion on the side of the first electrode layer, and a support portion including an opposite surface to the support surface and allowing gas to pass between the support surface and the opposite surface, wherein an adhesive layer adhering to the support surface is disposed in an opposing region of the support surface facing the peripheral edge of the first electrode layer, the inside of the peripheral edge of the first electrode layer being adhered to the support surface, and the peripheral edge of the first electrode layer being adhered to the adhesive layer.

2. The electrochemical cell according to claim 1, wherein the adhesive layer is disposed so as to surround the opposing region.

3. The electrochemical cell according to claim 1, wherein the support portion has through holes that allow gas to communicate between the support surface and the opposite surface.

4. The electrochemical cell according to claim 1, wherein the particle size of the material constituting the adhesive layer is smaller than the particle size of the material constituting the first electrode layer.

5. An electrochemical cell as described in claim 1, wherein the metal support further includes an outer periphery that forms the periphery of the support part, the adhesive layer is disposed so as to extend from the facing region to the outer periphery and surround the outer periphery, and the electrolyte layer surrounds and covers the side surface of the first electrode layer and is adhered to the adhesive layer disposed on the outer periphery while surrounding the adhesive layer.

6. An electrochemical cell as described in claim 5, wherein the electrolyte layer covers the adhesive layer arranged on the outer periphery and surrounds an outer region that is outside the electrolyte layer on the outer periphery while being adhered to the outer region.

7. The electrochemical cell of claim 1, wherein the material constituting the adhesion layer includes cerium oxide.

8. The electrochemical cell according to claim 1, wherein a coating containing an oxide of at least one of aluminum, chromium, silicon, manganese, cobalt, and nickel is formed on the main surface of the metal support on which the cell body is disposed.

9. The electrochemical cell according to claim 1, wherein the porosity of the first electrode layer in the adjacent region adjacent to the adhesive layer is lower than the porosity of the region other than the adjacent region of the first electrode layer.

10. An electrochemical cell as described in claim 1, wherein the second electrode layer is arranged so that the outer shape of the second electrode layer is more inward than the outer shape of the first electrode layer in a planar view, and the adhesive layer is arranged so as to be spaced apart from the area that overlaps with the second electrode layer in a planar view.

11. A solid oxide fuel cell using the electrochemical cell according to any one of claims 1 to 9, wherein the electrolyte layer is made of an oxygen ion conductive oxide, and a cathode gas is supplied to the second electrode layer, and an anode gas is supplied to the first electrode layer via the support, thereby enabling the cell main body to generate electricity.

12. A solid oxide electrolysis cell using the electrochemical cell according to any one of claims 1 to 9, wherein the electrolyte layer is made of an oxygen ion conductive oxide, and water is supplied to the first electrode layer via the support part, and a voltage is applied between the first electrode layer and the second electrode layer, thereby making it possible to electrolyze the water supplied to the first electrode layer.

13. A method for manufacturing an electrochemical cell in which a first electrode layer, an electrolyte layer, and a second electrode layer are laminated in this order on a metal support, the metal support including a support surface that supports the first electrode layer and an opposite surface to the support surface, and gas can be communicated between the support surface and the opposite surface, the method comprising laminating an adhesive layer on the peripheral edge of the support surface, and laminating the first electrode layer on the support surface while disposing the first electrode layer so that the peripheral edge rests on the adhesive layer.

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