JP2013077396A - Anode support substrate and anode support type cell using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anode support substrate capable of further enhancing mechanical strength of a cell while suppressing deterioration of power generation performance of the cell, and to provide an anode support type cell using the same.SOLUTION: An anode support type cell 1 comprises: an anode 11 including an anode support substrate 111; a cathode 12; and an electrolyte layer 13 arranged between the anode support substrate 111 and the cathode 12. The electrolyte layer 13 and the cathode 12 are supported by the anode support substrate 111. The anode support substrate 111 contains a conductive component and a skeleton component containing zirconia. The zirconia contains 2-11 mol% of a rare-earth metal oxide or alkaline earth metal oxide as a stabilizer, and further contains an Al atom so that a molar ratio (Al/Zr) of the Al atom with respect to a Zr atom becomes 0.10-2.50.

Description

  The present invention relates to an anode support substrate for a solid oxide fuel cell and an anode support cell using the anode support substrate.

  In recent years, fuel cells have attracted attention as clean energy sources. Among the fuel cells, solid oxide fuel cells (hereinafter referred to as “SOFC”) that use solid ceramics as the electrolyte can utilize exhaust heat because of their high operating temperature, and are more efficient and power efficient. It is expected to be used in a wide range of fields from household power sources to large-scale power generation.

  The SOFC has a structure in which an electrolyte layer made of ceramic is disposed between a cathode (air electrode) and an anode (fuel electrode) as a basic structure. For example, in a flat SOFC, a single cell is formed by stacking a cathode, an electrolyte layer, and an anode, and a high output is obtained by stacking a plurality of the single cells with an interconnector interposed therebetween. Here, in order to improve the power generation performance of SOFC, it is effective to make the electrolyte layer dense and thin. This is because the electrolyte layer is required to have a denseness that reliably prevents mixing of the fuel gas serving as a power generation source and air and an excellent ionic conductivity that can suppress a conductive loss as much as possible. However, the thinner the electrolyte layer, the easier the cell breaks due to the stacking load when many cells are stacked. Accordingly, in order to make the electrolyte layer thinner, an anode-supporting cell has been proposed in which the anode is used as a support substrate (anode support substrate) and the strength of the cell is maintained.

  In order to ensure good power generation performance of the anode-supported cell, the anode support substrate is required to have sufficient gas permeability in addition to conductivity. This is because the anode support substrate needs to pass and diffuse the fuel gas and air serving as the power generation source and the exhaust gas (such as carbon dioxide and water vapor) generated by the oxidation of the fuel. Therefore, the anode support substrate is made of a porous ceramic material to ensure sufficient gas permeability. On the other hand, the anode support substrate is also required to have high mechanical strength. However, it is difficult to ensure high mechanical strength with a porous material. Therefore, development of an anode support substrate that can achieve both sufficient gas permeability and high mechanical strength is underway. For example, Patent Document 1 proposes an anode support substrate having sufficient gas permeability and high mechanical strength, which is obtained by improving the material of the anode support substrate.

Japanese Patent No. 4580681

  However, in recent years, there has been a further demand for thinner SOFC, and it is also required to reduce the thickness of the anode support substrate in the anode support cell. However, since the strength of the anode support substrate itself is reduced when the thickness of the anode support substrate is reduced, there arises a problem that, for example, the anode support substrate is cracked during cell assembly. When power generation is performed in a cell constituted by a cracked anode support substrate, oxygen and fuel (hydrogen) are used for the combustion reaction, so the output decreases. Therefore, in order to reduce the thickness of the anode support substrate, it is necessary to further improve the strength of the anode support substrate itself.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an anode support substrate capable of further improving the mechanical strength of a cell while maintaining important characteristics such as gas permeability and suppressing a decrease in power generation performance of the cell. To do. Another object of the present invention is to provide an anode supporting cell using the anode supporting substrate.

The present invention
An anode support substrate for SOFC,
Including a conductive component and a skeleton component;
The skeletal component comprises zirconia,
The zirconia contains 2 to 11 mol% of a rare earth metal oxide or an alkaline earth metal oxide as a stabilizer, and further contains Al atoms in a molar ratio of Al atoms to Zr atoms (Al / Zr) of 0.10. Including to be ~ 2.50,
An anode support substrate is provided.

The present invention also provides:
The anode support substrate of the present invention,
A cathode,
An electrolyte layer disposed between the anode support substrate and the cathode;
With
The electrolyte layer and the cathode are supported by the anode support substrate,
An anode supported cell is also provided.

  The anode support substrate of the present invention contains zirconia stabilized with a rare earth metal oxide or an alkaline earth metal oxide as a skeleton component. This zirconia contains Al atoms such that the molar ratio of Al atoms to Zr atoms (Al / Zr) is 0.10 to 2.50. By including such a skeleton component, the anode support substrate of the present invention can realize higher mechanical strength than the conventional anode support substrate. In addition, in the anode support substrate of the present invention, other characteristics necessary for the anode support substrate can be maintained, so that a decrease in the power generation performance of the cell can also be suppressed.

  The anode supporting cell of the present invention uses the anode supporting substrate having the high mechanical strength as described above. Therefore, the anode-supported cell of the present invention can maintain high cell strength even when the thickness of the anode support substrate is reduced as compared with the conventional one. That is, according to the anode-supported cell of the present invention, it is possible to reduce the thickness without reducing the mechanical strength of the cell.

It is sectional drawing which shows one Embodiment of the anode support type cell of this invention. It is a graph which shows a battery performance evaluation result about the cell of Example 1, and the cell of the comparative example 1.

  Embodiments of the anode-supported cell and anode support substrate of the present invention will be specifically described.

  FIG. 1 shows a cross-sectional view of the anode-supported cell of the present embodiment. The anode supported cell 1 of the present embodiment includes an anode 11, a cathode 12, and an electrolyte layer 13 disposed between the anode 11 and the cathode 12.

  The anode 11 is formed by an anode support substrate 111 and an anode layer 112 disposed on the surface of the anode support substrate 111 on the electrolyte layer 13 side. Note that the anode layer 112 may not be provided when the anode support substrate 111 itself can sufficiently function as an anode. The electrolyte layer 13 and the cathode 12 are supported by an anode support substrate 111.

  The anode support substrate 111 is formed of a material containing a conductive component and a skeleton component. The conductive component is a component for imparting conductivity to the anode support substrate 111. The skeletal component is a component that forms the skeleton of the anode support substrate 111 and is an important component in securing the strength necessary for the anode support substrate 111.

  The skeletal component of the anode support substrate 111 includes zirconia. This zirconia is a stabilized zirconia containing 2 to 11 mol% of a rare earth metal oxide or an alkaline earth metal oxide as a stabilizer, and further contains Al atoms. The amount of Al atoms contained in the zirconia is within a range where the molar ratio of Al atoms to Zr atoms (Al / Zr) satisfies 0.10 to 2.50.

  For example, stabilized zirconia containing 2.5 to 15 mol% of a rare earth metal oxide such as Sc, Y and Ce as a stabilizer, and 5 to 20 mol% of an alkaline earth metal oxide such as Mg and Ca. Is exemplified by stabilized zirconia containing as a stabilizer. These may be used in combination of two or more as required. Particularly preferred among these stabilized zirconia are 3-6 mol% yttria stabilized zirconia (YSZ) and 3-6 mol% scandia stabilized zirconia (ScSZ). .

  As described above, the amount of Al atoms contained in the stabilized zirconia is within a range where the molar ratio of Al atoms to Zr atoms (Al / Zr) is 0.10 to 2.50, preferably 0.25. It is in the range which becomes -2.00, More preferably, it exists in the range which becomes 0.50-1.50. Examples of the Al atom source added to the stabilized zirconia include alumina, aluminum hydroxide, and aluminum chloride. For example, when alumina is used as an additive, it is preferable to add 5 to 40% by mass of alumina with respect to the entire skeletal component, and to add 7.5 to 30% by mass. More preferably, it is more preferable to add so that it may become 10-25 mass%.

  A particularly preferable example is zirconia in which the zirconia contained in the anode support substrate 111 is stabilized with 3 to 6 mol% yttria in which 20 mass% of alumina is uniformly dispersed.

  By including stabilized zirconia to which alumina is added in the above-described range, anode support substrate 111 of the present embodiment can realize high mechanical strength of the cell. It is desirable that the alumina is uniformly dispersed in the stabilized zirconia. Therefore, it is preferable that the stabilized zirconia powder in which alumina is uniformly dispersed is used as a raw material, and the sintered body of the zirconium powder forms the anode support substrate 111 of the present embodiment. In the anode support substrate 111, 5% by mass or more of the skeletal component is preferably stabilized zirconia containing Al atoms in the above range. More preferably, the skeletal component of the anode support substrate 111 is made of stabilized zirconia containing Al atoms in the above range. The skeletal component may contain ceria doped with oxides of rare earth elements such as Gd, Sm, and Y in addition to stabilized zirconia containing Al atoms.

  The conductive component of the anode support substrate 111 is a metal such as nickel, cobalt, iron, platinum, palladium, ruthenium, etc .; changes to a conductive metal in a reducing atmosphere during fuel cell operation, such as nickel oxide, cobalt oxide, and iron oxide. Or a composite metal oxide such as nickel ferrite or cobalt ferrite containing two or more of these oxides. These may be used alone or in combination of two or more as necessary. Among these, metallic nickel, metallic cobalt, metallic iron, and oxides thereof are preferable.

  The ratio of the conductive component to the skeletal component is 30% by mass / 70% by mass or more and 80% by mass when the sum of these is 100% by mass. / 20% by mass or less, more preferably 40% by mass / 60% by mass or more and 70% by mass / 30% by mass or less. In addition, the quantity of a conductive component here is the quantity converted into the quantity when a conductive component exists as an oxide.

  The thickness of the anode support substrate 111 is not particularly limited, but is preferably, for example, 100 μm or more, more preferably 120 μm or more, and further preferably 150 μm or more. The thickness of the anode support substrate 111 is preferably 3 mm or less, more preferably 2 mm or less, still more preferably 1 mm or less, and particularly preferably 500 μm or less. When the thickness of the anode support substrate 111 is within the above range, the mechanical strength and gas permeability of the anode support substrate 111 are easily balanced and balanced.

  The porosity of the anode support substrate 111 is not particularly limited, but the porosity after the reduction treatment is, for example, preferably 10% or more, more preferably 15% or more, and further preferably 20% or more. Further, the porosity of the anode support substrate 111 is preferably 50% or less, more preferably 45% or less, and further preferably 40% or less. When the porosity of the anode support substrate 111 is within the above range, the mechanical strength and gas permeability of the anode support substrate 111 can be easily balanced.

In addition, the porosity here is the porosity calculated | required based on "The measuring method of the apparent porosity of a refractory brick" of JISR2205. The subsequent porosity is also the same. The apparent porosity (P ₀ ) of the sample is expressed by the following formula (1) from the mass of the dry sample (W ₁ ), the mass of the saturated sample in water (W ₂ ), and the mass of the saturated sample (W ₃ ). Calculated.
P ₀ = {(W ₃ −W ₁ ) / (W ₃ −W ₂ )} × 100 (1)

  Similar to the anode support substrate 111, the anode layer 112 includes a conductive component and a skeleton component. The conductive component of the anode layer 112 can be appropriately selected from the materials exemplified as the conductive component of the anode support substrate 111. Materials that can be used as the skeleton component of the anode layer 112 are zirconia, alumina, magnesia, titania, aluminum nitride, mullite, and the like. Among these, stabilized zirconia using a rare earth metal oxide or an alkaline earth metal oxide as a stabilizer is preferable. The stabilized zirconia to which alumina used for the anode support substrate 111 is added can also be used as a skeleton component of the anode layer 112.

  Although the thickness of the anode layer 112 is not specifically limited, For example, 5 micrometers or more are preferable, 7 micrometers or more are more preferable, and 10 micrometers or more are further more preferable. The thickness of the anode layer 112 is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 30 μm or less. When the thickness of the anode layer 112 is within the above range, the electrode reaction is efficiently performed, and the power generation performance is better when the anode-supported cell is formed.

  Since a general SOFC electrolyte layer can be applied to the electrolyte layer 13, the material is not particularly limited. Specifically, the electrolyte layer 13 contains ceramic as a main component. The ceramic material is not particularly limited as long as it is normally used as a material for the SOFC electrolyte layer. For example, zirconia stabilized with yttria, ceria, scandia, ytterbia, etc .; ceria doped with yttria, samaria, gadolinia, etc .; lanthanum gallate and lanthanum gallium in lanthanum or gallium are part of strontium, calcium, barium, magnesium A lanthanum gallate perovskite structure oxide substituted with aluminum, indium, cobalt, iron, nickel, copper, or the like can be used. These may be used alone or in combination of two or more. Among these, zirconia stabilized with yttria, scandia, ytterbia and the like is preferable.

  Particularly, zirconia stabilized with 3 to 10 mol% yttria stabilized as a ceramic material, zirconia stabilized with 4 to 12 mol% scandia, and 8 to 12 mol% scandia. Zirconia stabilized with zirconia, zirconia stabilized with 4 mol% or more and 15 mol% or less of ytterbia, zirconia stabilized with 8 to 12 mol% scandia and 0.5 to 5 mol% ceria Is preferred. A material obtained by adding alumina, silica, titania or the like as a sintering aid or dispersion strengthening agent to these stabilized zirconia can also be suitably used.

  Although the thickness of the electrolyte layer 13 is not specifically limited, For example, 3 micrometers or more are preferable, 4 micrometers or more are more preferable, and 5 micrometers or more are further more preferable. Further, the thickness of the electrolyte layer 13 is preferably 50 μm or less, more preferably 30 μm or less, and further preferably 20 μm or less. If the thickness of the electrolyte layer 13 is within the above range, when an anode-supported cell is used, power generation performance is improved while preventing gas cross-leakage.

  The porosity of the electrolyte layer 13 is not particularly limited, but is preferably 10% or less, more preferably 7% or less, and still more preferably 5% or less. If the porosity of the electrolyte layer 13 is within the above range, the mechanical strength of the electrolyte layer 13 will be sufficient, and the gas tightness of fuel gas and air will be good.

The cathode 12 is generally made of a perovskite oxide that has excellent electron conductivity and is stable even in an oxidizing atmosphere. Specifically, lanthanum manganite in which a part of lanthanum such as La _0.8 Sr _0.2 MnO ₃ , La _0.6 Sr _0.4 CoO ₃ , La _0.6 Sr _0.4 FeO ₃ and La _0.6 Sr _0.4 Co _0.2 Fe _0.8 O ₃ is substituted with strontium. Lanthanum ferrite, lanthanum cobaltite and the like are preferably used. Further, in order to impart ion conductivity to the cathode 12, a stabilized zirconia containing 2.5 to 15 mol% of a rare earth metal oxide such as Sc, Y and Ce or an alkaline earth metal oxide as a stabilizer. Alternatively, ceria doped with a rare earth element oxide or the like can be appropriately mixed.

  Although the thickness of the cathode 12 is not specifically limited, For example, 5 micrometers or more are preferable, 7 micrometers or more are more preferable, and 10 micrometers or more are further more preferable. Further, the thickness of the cathode 12 is preferably 80 μm or less, more preferably 70 μm or less, and further preferably 60 μm or less. When the thickness of the cathode 12 is within the above range, the electrode reaction is efficiently performed, and the power generation performance is improved when the anode-supported cell is used.

  The anode-supported cell 1 of the present embodiment has a configuration in which the electrolyte layer 13 and the cathode 12 are adjacent to each other. However, the anode supported cell 1 of the present invention is not limited to this configuration, and may further include another layer between the electrolyte layer 13 and the cathode 12. For example, depending on the material used for the cathode 12, a barrier layer may be provided between the electrolyte layer 13 and the cathode 12. This barrier layer can be expected to have an effect of suppressing the generation of an insulating material occurring between the electrolyte layer 13 and the cathode 12 or an effect of promoting power generation in a high temperature atmosphere during cell production or during power generation. In general, a ceria doped with an oxide of rare earth elements such as Gd, Sm, and Y is used as a material having oxide ion conductivity.

  Next, a method for manufacturing the anode supported cell 1 will be described. An example of a method for manufacturing the anode-supported cell 1 includes a step of producing a multilayer fired body including the anode 11 and the electrolyte layer 13, and a step of cutting and / or punching the obtained multilayer fired body into a predetermined shape. And a step of producing a cathode 12 on a surface opposite to the anode 11 in the multilayer fired body cut into a predetermined shape.

The multilayer fired body
(1) A configuration in which a green layer for the anode layer 112 (not required in the case where the anode layer 112 is not provided), a green layer for the electrolyte layer 13, and a barrier layer are provided on the green sheet for the anode support substrate 111. In the case of, after forming a laminate in which the green layer for the barrier layer and the layer are sequentially stacked, a method of firing these whole at once,
Or
(2) A green sheet for the anode support substrate 111 is baked to produce the anode support substrate 111, and a green layer for the anode layer 112 (not necessary in the case of the configuration without the anode layer 112) thereon, and an electrolyte layer In the case of a configuration in which a green layer for 13 and a barrier layer are provided, a green body for a barrier layer is formed in order, and then a method of firing them,
Can be used. Here, the method for producing a multilayer fired body will be described by taking the method (1) as an example.

  First, a green sheet for the anode support substrate 111 is prepared. The green sheet for the anode support substrate 111 is prepared by mixing a raw material powder (conductive component powder and skeletal component powder), a pore-forming agent, a binder and a solvent, and further adding a dispersant, a plasticizer, and the like as necessary. Add slurry to prepare a slurry, and form the slurry into a sheet having a predetermined thickness by any method such as doctor blade method, calender roll method, extrusion method, etc., and dry this to volatilize and remove the solvent. Is obtained by

  Examples of substances that can be used as the conductive component are as described above. The size of the conductive component powder is not particularly limited. However, the conductive component powder preferably has an average particle size of 0.2 μm or more and 5 μm or less, a 90% by volume diameter of 15 μm or less, an average particle size of 0.3 μm or more and 3 μm or less, and More preferably, the 90 volume% diameter is 10 μm or less, the average particle diameter is 0.4 μm or more and 2 μm or less, and the 90 volume% diameter is 8 μm or less. In addition, the average particle diameter in this specification is a median diameter calculated | required from particle size distribution, ie, the particle diameter (D50) equivalent to 50% of volume accumulation. The 90 volume% diameter is a particle diameter (D90) corresponding to 90% of the volume particle diameter from the smaller particle diameter side in the particle size distribution. Here, the particle size of the powder specified in this specification is a particle size measured based on a laser diffraction scattering method.

  The skeletal component contains, for example, 2 to 11 mol% of rare earth metal oxide or alkaline earth metal oxide as a stabilizer, and further stabilized zirconia powder containing 5 to 40 mass% of alumina as an additive. Can be used. Such stabilized zirconia powder containing alumina can be produced by a method such as a coprecipitation method or a Pecini method. The stabilized zirconia powder obtained by such a method is preferable because alumina is more uniformly dispersed.

  The size of the powder of the skeleton component is not particularly limited. However, the powder of the skeleton component preferably has an average particle size of 0.1 μm or more and 3 μm or less, a 90% by volume diameter of 6 μm or less, and an average particle size of 0.1 μm or more and 1.5 μm or less. More preferably, the 90 volume% diameter is 3 μm or less, the average particle diameter is 0.2 μm or more and 1 μm or less, and the 90 volume% diameter is 2 μm or less.

  The pore forming agent is not particularly limited as long as it burns away when the green sheet is fired. For example, cross-linked fine particle aggregates made of acrylic resin, etc .; natural organic powders such as wheat flour, corn starch (corn starch), sweet potato starch, potato starch, tapioca starch; thermal decomposable or sublimable resin powder such as melamine cyanurate Body: Carbonaceous powder such as carbon black and activated carbon, and the like. These may be used alone or in combination of two or more.

  The average particle diameter of the pore forming agent is preferably 0.5 μm or more and 100 μm or less, and more preferably 3 μm or more and 50 μm or less. Also. The pore-forming agent has a 10% by volume diameter (a particle diameter corresponding to 10% of the volume particle diameter from the smaller particle size distribution in the particle size distribution), preferably 0.1 μm to 10 μm, and more preferably 1 μm to 5 μm. .

  The amount of the pore-forming agent added is preferably 2 parts by mass or more, and more preferably 5 parts by mass or more with respect to 100 parts by mass in total of the conductive component powder and the skeleton component powder. The amount of the pore-forming agent added is preferably 40 parts by mass or less, and more preferably 30 parts by mass or less, with respect to 100 parts by mass in total of the conductive component powder and the skeleton component powder. By setting the use amount of the pore forming agent within the above range, pores are appropriately formed by thermal decomposition during firing, and the gas permeability and mechanical strength of the anode support substrate 111 become better.

  The binder is not particularly limited, and can be appropriately selected from organic binders known in conventional production methods for anode-supported cells. Examples of organic binders include ethylene copolymers, styrene copolymers, acrylate and methacrylate copolymers, vinyl acetate copolymers, maleic acid copolymers, vinyl butyral resins, and vinyl acetal series. Examples thereof include resins, vinyl formal resins, vinyl alcohol resins, waxes, and celluloses such as ethyl cellulose. These may be used alone or in combination of two or more.

  The solvent is not particularly limited, and various organic solvents such as alcohols, glycol ethers, aliphatic hydrocarbons, ketones, esters, and aromatic hydrocarbons can be used. Specific examples of the organic solvent include α-terpineol, dihydroterpineol, methanol, ethanol, isopropyl alcohol, 1-butanol, 1-hexanol, glycerin, polyethylene glycol and other alcohols; butyl carbitol acetate, butyl carbitol and the like. Glycol ethers; aliphatic hydrocarbons such as pentane, hexane, heptane, kerosene and cyclohexane; ketones such as acetone and 2-butanone; esters such as ethyl acetate, methyl acetate, butyl acetate, terpineol acetate and dihydroterpineol acetate And aromatic hydrocarbons such as toluene and xylene. These may be used alone or in combination of two or more. Among these, ethyl acetate, methyl acetate, butyl acetate, methanol, ethanol, acetone, xylene, pentane, hexane, heptane and the like are preferable in order to accelerate drying after coating.

  The dispersant promotes peptization and dispersion of the ceramic powder. Examples of the dispersant include polyelectrolytes such as polyacrylic acid and ammonium polyacrylate; organic acids such as citric acid and tartaric acid; copolymers of isobutylene or styrene and maleic anhydride and ammonium salts or amine salts thereof; Examples thereof include a copolymer of butadiene and maleic anhydride, and an ammonium salt thereof.

  The plasticizer imparts flexibility to the anode support substrate 111. Plasticizers include phthalates such as dibutyl phthalate, dioctyl phthalate, and ditridecyl phthalate; glycols and glycol ethers such as propylene glycol; phthalic polyesters, adipic acid polyesters, sebacic acid polyesters, etc. Polyesters.

  A green layer for the anode layer 112 is formed on the green sheet for the anode support substrate 111 using the paste for the anode layer 112. The paste for the anode layer 112 is a mixture of raw material powder (conductive component powder and skeletal component powder), a pore-forming agent, a binder and a solvent, and a dispersant, a plasticizer and the like are added as necessary. To be prepared. This paste is applied onto a green sheet for the anode support substrate 111 by using a method such as screen printing, and dried to form a green layer for the anode layer 112. The conductive component powder, the skeleton component powder, the pore forming agent, the binder, the solvent, the dispersing agent, the plasticizer, and the like are exemplified as materials used when producing a green sheet for the anode support substrate 111. The description can be omitted here.

  A green layer for the electrolyte layer 13 is formed on the green layer for the anode layer 112 by using the paste for the electrolyte layer 13. The paste for the electrolyte layer 13 is prepared by mixing at least a ceramic powder as a ceramic raw material and a solvent.

  The ceramic powder is not particularly limited. For example, it is preferable to use a ceramic powder having an average particle size of 0.3 μm or more and 0.7 μm or less. Moreover, as ceramic powder, the thing with a small particle size distribution is suitable. Specifically, it is preferable that the average particle size is 0.3 μm or more and 0.7 μm or less, and the 90% by volume diameter is 1.2 μm or less, and the average particle size is 0.4 μm or more and 0.6 μm or less. More preferably, the 90% by volume diameter is 1.0 μm or less.

  The solvent used for the paste for the electrolyte layer 13 is not particularly limited, and can be selected and used from the substances exemplified as the solvent used for the slurry for the anode support substrate 111. A solvent may be used independently and may use 2 or more types together.

  In addition to the ceramic powder and the solvent, a binder, a dispersant, a plasticizer, a surfactant, an antifoaming agent, and the like may be added to the paste for the electrolyte layer 13. The binder, the dispersant, and the plasticizer can be selected from substances exemplified as the slurry material for the anode support substrate 111 according to the material of the electrolyte layer 13 to be formed. The paste for the electrolyte layer 13 is prepared by mixing an appropriate amount of the above components. At that time, in order to make each particle fine or to make the particle size uniform, the particles may be mixed while being pulverized using a ball mill or the like. Moreover, the order of addition of each component is not particularly limited, and may be according to a conventional method.

  If necessary, a green layer for a barrier layer is formed on the green layer for the electrolyte layer 13. Similarly to the anode layer 112 and the electrolyte layer 13, the green layer for the barrier layer is prepared by preparing a paste containing the raw material powder constituting the barrier layer, and applying the paste onto the green layer for the electrolyte layer 13 and drying it. Can be formed.

  On the green sheet for the anode support substrate 111, the green layer for the anode layer 112, the green layer for the electrolyte layer 13, and the green layer for the barrier layer in the case where the barrier layer is provided are sequentially stacked. The laminated body formed by the above is fired all at once. The firing temperature of the laminate is not particularly limited, but is preferably 1100 ° C. or higher, more preferably 1200 ° C. or higher, and further preferably 1250 ° C. or higher. The firing temperature is preferably 1500 ° C. or lower, more preferably 1400 ° C. or lower, and further preferably 1350 ° C. or lower. The firing time during firing is not particularly limited, but is preferably 0.1 hours or longer, more preferably 0.5 hours or longer, and even more preferably 1 hour or longer. The firing time is preferably 10 hours or less, more preferably 7 hours or less, and even more preferably 5 hours or less.

  A multilayer fired body is obtained by the method as described above. Next, the obtained multilayer fired body is cut and / or punched into a predetermined shape.

  Next, the cathode 12 is produced on the surface opposite to the anode 11 in the multilayer fired body cut into a predetermined shape. The cathode 12 is produced by forming a green layer for the cathode 12 using the paste for the cathode 12 and firing the green layer. The paste for the cathode 12 is prepared by uniformly mixing together the raw material powder, the binder and the solvent constituting the cathode 12 and, if necessary, the dispersant and the plasticizer. A binder, a solvent, a dispersant, a plasticizer, and the like can be selected from substances exemplified as the material for the slurry for the anode support substrate 111 and used. The prepared paste is applied onto the multilayer fired body by screen printing or the like and dried to form a green layer for the cathode 12. By baking this, the cathode 12 is produced. Although a calcination temperature is not specifically limited, 800 degreeC or more is preferable, 850 degreeC or more is more preferable, and 950 degreeC or more is further more preferable. The firing temperature is preferably 1300 ° C. or lower, more preferably 1250 ° C. or lower, and further preferably 1200 ° C. or lower. The firing time during firing is not particularly limited, but is preferably 0.1 hours or longer, more preferably 0.5 hours or longer, and even more preferably 1 hour or longer. The firing time is preferably 10 hours or less, more preferably 7 hours or less, and even more preferably 5 hours or less.

  By the method as described above, the anode-supported cell 1 having high mechanical strength can be manufactured.

  Next, the present invention will be specifically described using examples. In addition, this invention is not limited at all by the Example shown below.

Example 1
1. 1. Production of anode-supported cell 1-1. Production of Green Sheet for Anode Support Substrate As a conductive component, nickel oxide (NiO, manufactured by Shodo Chemical Industry Co., Ltd.) 60 parts by mass,
40 parts by mass of 3 mol% yttrium-stabilized zirconia powder (trade name “TZ3Y-20A”, manufactured by Tosoh Corporation) to which 20% by mass of alumina is added as a skeleton component;
As a pore forming agent, 10 parts by mass of carbon black (trade name “SGP-3” manufactured by SEC Carbon Co., Ltd.),
As a binder, 30 parts by mass of a methacrylate copolymer (molecular weight: 30,000, glass transition temperature: −8 ° C., solid content concentration: 50% by mass),
As a plasticizer, 2 parts by mass of dibutyl phthalate,
As a solvent, 80 parts by mass of a mixed solvent of toluene / isopropyl alcohol (mass ratio = 3/2),
Were mixed by a ball mill to prepare a slurry. The obtained slurry was used, formed into a sheet by the doctor blade method, and dried at 70 ° C. for 5 hours. As a result, a green sheet for an anode support substrate having a thickness of 300 μm was obtained.

1-2. Production of paste for anode layer As conductive component, 36 parts by mass of nickel oxide (NiO, manufactured by Kishida Chemical Co., Ltd.)
As a skeleton component, 24 parts by mass of 8 mol% yttrium-stabilized zirconia powder (manufactured by Daiichi Rare Element Chemical Co., Ltd., trade name “HSY-8.0”),
As a pore forming agent, 2 parts by mass of carbon black (trade name “SGP-3” manufactured by SEC Carbon Co., Ltd.),
As a solvent, 36 parts by mass of α-terpineol (manufactured by Wako Pure Chemical Industries, Ltd.)
As a binder, 4 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.),
As a plasticizer, 6 parts by mass of dibutyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.)
As a dispersant, 4 parts by mass of a sorbitan fatty acid ester surfactant,
Were mixed using a mortar, and then crushed using a three-roll mill (EXAKT technologies, model “M-80S”, roll material: alumina). As a result, a paste for the anode layer was obtained.

1-3. Preparation of paste for electrolyte layer As ceramic powder, 8 parts by mass of yttrium-stabilized zirconia powder (trade name “HSY-8.0”, manufactured by Daiichi Rare Element Chemical Co., Ltd.), 60 parts by mass,
As a binder, 5 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.)
As a solvent, 40 parts by mass of α-terpineol (manufactured by Wako Pure Chemical Industries, Ltd.),
As a plasticizer, 6 parts by mass of dibutyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.)
As a dispersant, 5 parts by mass of a sorbitan acid ester surfactant (manufactured by Sanyo Kasei Kogyo Co., Ltd., trade name “Ionet S-80”),
Were mixed using a mortar, and then crushed using a three-roll mill (EXAKT technologies, model “M-80S”, roll material: alumina). Thereby, the paste for electrolyte layers was obtained.

1-4. Preparation of paste for barrier layer 60 parts by mass of ceria powder (manufactured by Anan Kasei Co., Ltd.) doped with 10 mol% gadolinia as ceramic powder,
As a binder, 5 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.)
As a solvent, 40 parts by mass of α-terpineol (manufactured by Wako Pure Chemical Industries, Ltd.),
As a plasticizer, 6 parts by mass of dibutyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.)
As a dispersant, 5 parts by mass of a sorbitan acid ester surfactant (manufactured by Sanyo Kasei Kogyo Co., Ltd., trade name “Ionet S-80”),
Were mixed using a mortar, and then crushed using a three-roll mill (EXAKT technologies, model “M-80S”, roll material: alumina). As a result, a barrier layer paste was obtained.

1-5. Formation of Green Layer for Anode Layer On the green sheet for the anode support substrate obtained in 1-1 above, the paste for the pulverized anode layer obtained in 1-2 above is thickened by screen printing. It printed so that it might become 20 micrometers. This was dried at 100 ° C. for 30 minutes to form a green layer for the anode layer.

1-6. Formation of Green Layer for Electrolyte Layer On the green layer for the anode layer formed in 1-5 above, the paste for the crushed electrolyte layer obtained in 1-3 above is formed by screen printing to a thickness of 15 μm. It was printed as follows. This was dried at 100 ° C. for 30 minutes to form a green layer for an electrolyte layer.

1-7. Formation of Green Layer for Barrier Layer On the green layer for electrolyte layer formed in 1-6 above, the paste for barrier layer after pulverization obtained in 1-4 above is 3 μm or less in thickness by screen printing. It was printed as follows. This was dried at 100 ° C. for 30 minutes to form a green layer for the barrier layer.

1-8. After drying the paste for the barrier layer, the green sheet for the anode support substrate on which the green layer for the barrier layer, the green layer for the electrolyte layer, and the green layer for the anode layer obtained above are formed is used for the strength test. For cell preparation, punching was performed so that the diameter after firing would be φ50 mm. For cell production for battery performance evaluation, punching was performed so that one side after firing was a square of 60 mm. After punching, each was fired at 1300 ° C. for 2 hours to prepare the following half cells (1) and (2).
(1) φ50 mm anode supported half cell (round, for strength test) 10 sheets (2) Anode supported half cell (square, battery performance evaluation) 3 sheets of 60 mm per side

1-9. Preparation of cathode paste Perovskite oxide powder La _0.6 Sr _0.4 Co _0.2 Fe _0.8 O ₃ (Aldrich) 60 parts by mass,
As a solvent, 36 parts by mass of α-terpineol (manufactured by Wako Pure Chemical Industries, Ltd.)
As a binder, 4 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.),
As a plasticizer, 6 parts by mass of dibutyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.)
As a dispersant, 4 parts by mass of a sorbitan fatty acid ester surfactant,
Were mixed using a mortar, and then crushed using a three-roll mill (EXAKT technologies, model “M-80S”, roll material: alumina). As a result, a paste for the cathode was obtained.

1-10. Formation of cathode 1-8. On the barrier layer of the half cell obtained in (1) and (2) by screen printing,
(1) The strength test cell is a circle having a diameter of 46 mm. (2) The battery performance evaluation cell is a cathode paste obtained in the above 1-9 so as to be a square having a side of 1 cm. Was applied. This was dried at 90 ° C. for 1 hour and then calcined at 1000 ° C. for 2 hours. As a result, an anode-supported cell was obtained.

2. Strength Test A strength test was carried out on each of the 10 φ50 mm anode-supported cells obtained in (1) of 1-10 above by a method according to ASTM C1499-03. Table 1 shows the average value of the strength test results obtained for 10 anode-supported cells as the strength.

3. Battery performance evaluation test As an evaluation of the anode-supported cell, a battery performance evaluation test based on current-voltage characteristics was performed.
Three anode-supported cells obtained in the above 1-10 (2) were used. First, the anode-supported cell was heated to a measurement temperature (750 ° C.) at a rate of 200 ° C./h while supplying 100 mL / min of nitrogen to the anode and 100 mL / min of air to the cathode. After raising the temperature, the flow rate of the anode and cathode outlet gas was measured using a flow meter, and it was confirmed that there was no gas leakage.
Then, a humidified mixed gas of 6 mL / min hydrogen and 194 mL / min nitrogen was supplied to the anode, and 400 mL / min air was supplied to the cathode. After confirming again that an electromotive force is generated after 10 minutes or more and that there is no leakage, humidified hydrogen is supplied to the anode at a flow rate of 200 mL / min, and current-voltage characteristics (IV), current-output characteristics (IP ) Battery performance evaluation test was conducted. The result of one of the three anode-supported cells is shown in FIG.

(Comparative Example 1)
In the preparation of the green sheet for the anode support substrate of Example 1-1 of Example 1, “3 mol” was used instead of “3 mol% yttrium-stabilized zirconia powder to which 20 mass% alumina was added” as a skeleton component. An anode-supported cell was produced in the same manner as in Example 1 except that “% yttrium-stabilized zirconia powder” was used. The obtained anode-supported cell of Comparative Example 1 was subjected to a strength test and a battery performance evaluation test in the same manner as in Example 1.

(Comparative Example 2)
In the preparation of the green sheet for the anode support substrate of Example 1 of Example 1, instead of “a 3 mol% yttrium-stabilized zirconia powder to which 20 mass% of alumina is added” as a skeleton component, “alumina An anode supported cell was produced in the same manner as in Example 1 except that “powder” was used. The obtained anode-supported cell of Comparative Example 2 was subjected to a strength test in the same manner as in Example 1. As a result, as shown in Table 1, the strength of the cell of Comparative Example 2 was significantly lower than that of the cells of Example 1 and Comparative Example 1.

  From the results shown in Table 1, when yttria-stabilized zirconia containing 20% by mass of alumina as an additive is used as the skeletal component of the anode support substrate, when using zirconia without adding alumina, or using only alumina. It was confirmed that the mechanical strength of the cell was significantly increased. As shown in FIG. 1, the battery performance of the cell of Example 1 was almost the same as the cell of Comparative Example 1. In the cell of Comparative Example 1, general stabilized zirconia is used as a skeletal component of the anode support substrate. That is, the cell of Comparative Example 1 is an anode-supported cell having conventional general power generation performance. Therefore, only the strength of the cell of the cell of Example 1 was significantly improved over the conventional cell while maintaining the power generation performance of the conventional cell.

  According to the anode support substrate of the present invention and the anode support cell using the same, it is possible to further improve the mechanical strength while suppressing a decrease in the power generation performance of the cell. Even when it is reduced more, sufficient cell strength can be secured. Therefore, the anode support substrate of the present invention and the anode support cell using the same can be suitably used for SOFCs that require high strength and SOFCs that require further thickness reduction.

DESCRIPTION OF SYMBOLS 1 Anode support type cell 11 Anode 12 Cathode 13 Electrolyte layer 111 Anode support substrate 112 Anode layer

Claims (2)

An anode support substrate for a solid oxide fuel cell,
Including a conductive component and a skeleton component;
The skeletal component comprises zirconia,
The zirconia contains 2 to 11 mol% of a rare earth metal oxide or an alkaline earth metal oxide as a stabilizer, and further contains Al atoms in a molar ratio of Al atoms to Zr atoms (Al / Zr) of 0.10. Including to be ~ 2.50,
Anode support substrate. An anode support substrate according to claim 1;
A cathode,
An electrolyte layer disposed between the anode support substrate and the cathode;
With
The electrolyte layer and the cathode are supported by the anode support substrate;
Anode-supported cell.

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