WO2005015671A1

WO2005015671A1 - Solid oxide fuel cell

Info

Publication number: WO2005015671A1
Application number: PCT/JP2004/011368
Authority: WO
Inventors: Kenichi Hiwatashi; Hironobu Murakami; Tomoyuki Nakamura; Mitsunobu Shiono
Original assignee: Toto Ltd.
Priority date: 2003-08-06
Filing date: 2004-08-06
Publication date: 2005-02-17
Also published as: CA2553074A1; JP4362832B2; JPWO2005015671A1

Abstract

A solid oxide fuel cell is disclosed which is excellent in output performance and durability. The solid oxide fuel cell comprises at least an electrolyte, an air electrode and a fuel electrode, and the air electrode includes a perovskite oxide containing at least manganese. A layer which is in contact with the fuel electrode is formed to contain 0.3-4 weight% of manganese in the surface facing the fuel electrode. This invention has been made basing on the finding such that, in a solid oxide fuel cell having an air electrode composed of a perovskite oxide containing manganese, the manganese content in the fuel electrode side surface of a layer which is in contact with the fuel electrode greatly affects the performance of the fuel cell, and thus an excellent fuel cell can be obtained by controlling this manganese content.

Description

Specification

Solid oxide fuel cell

Background of the Invention

[0001] ^^ Moon Village

The present invention relates to a solid oxide fuel cell, and more particularly, to a solid oxide fuel cell excellent in output performance and durability.

[0002] sampling

Solid oxide fuel cells have high operating temperatures (900-1000 ° C) and are expected to be efficient fuel cells. Various proposals have been made to realize a solid oxide fuel cell having excellent output performance and durability.

[0003] For example, in a solid oxide fuel cell, in order to improve oxygen ion conductivity stability and high-temperature strength stability of an electrolyte composed of dinorecoure in which scandia is dissolved, groups 4A, 5A, and 7A are used. Japanese Patent Application Laid-Open Nos. 2003-22821 and 2003-22822 propose to add at least one oxide selected from the group consisting of Group 4B and Group 4B elements.

[0004] However, these publications do not disclose a combination with an air electrode composed of a lobskite oxide containing manganese, and manganese is added as an oxide Mn of the 7A group.

2 It is said that it will be added, but the amount added is not clear.

[0005] Further, Japanese Patent Application Laid-Open No. 2003-187811 discloses that an oxygen gas generated in an air electrode and an electrolyte reacts with an electron to generate an oxygen ion. It has been proposed to provide a mixed material of a perovskite oxide having electronic conductivity and a high-melting dielectric oxide between electrolytes. As a representative of the perovskite-type oxide used here, there is lanthanum manganite in which Sr or Ca is dissolved, and its composition is (La, Sr) MnO, (La, Ca) MnO, (La, Sr) (Mn Fe) 0

1 δ 3 1 δ 3 1 δ y 1—y 3 In addition, cerium containing SmO or GdO as a solid solution

2 3 2 3

Oxides have been proposed.

[0006] In addition, Japanese Patent Application Laid-Open No. 8-41674 (Koyama, (La Sr) Mn〇 (However, 0.1 l≤xl≤0.4)

1-xl xl 3

40 to 60 parts by weight of zirconia obtained by dissolving yttria in lanthanum manganite represented by It has been proposed that the use of the mixed material for the air electrode of a solid oxide fuel cell not only improves the electrode reaction between the air electrode and the electrolyte but also excels in durability.

[0007] JP-A-8-180886 discloses that a thin layer of zirconia in which yttria is dissolved as a solid solution is provided between an air electrode and an electrolyte to reduce the contact resistance between the air electrode and the electrolyte. It is disclosed that performance can be improved. The cathode material used here is lanthanum manganite in which Sr is dissolved.

[0008] Further, Japanese Patent Application Laid-Open No. 2000-44245 discloses a mixed powder of lanthanum manganite in which Ca and Z or Sr are formed as a solid solution between an air electrode and an electrolyte and zirconia in which yttria is formed as a solid solution. It has been proposed that a layer be provided to reduce the contact resistance between the air electrode and the electrolyte, thereby improving the output performance.

[0009] Also, Japanese Patent Application Laid-Open No. 2003-173801 discloses that in a solid oxide fuel cell, in order to prevent a reaction between an electrolyte and a fuel electrode, Ce Ln〇 (porosity is 25% or less) is used.

1-x x 2-δ However, it has been proposed to provide a layer made of a cerium-containing oxide represented by Ln: a rare earth element and 0.05 ≦ x ≦ 0.3).

[0010] However, even in these prior arts, to the knowledge of the present inventors, there is no disclosure or suggestion of controlling the diffusion of manganese through an electrolyte.

On the other hand, Japanese Patent Application Laid-Open No. 2002-134132 discloses a solid oxide fuel cell in which an air electrode made of a perovskite-type oxide containing manganese and an electrolyte made of dinoreconia are co-sintered. There is a proposal to suppress the diffusion of manganese into the fuel electrode by providing an oxide layer containing yttria, dinoreconia and ceria between the electrode and the electrolyte. However, oxides containing yttria, zirconia and ceria required a sintering temperature of around 1500 ° C to form an electrolyte with low sinterability and no gas permeability. For this reason, it seems difficult to control the amount of manganese that diffuses through the electrolyte to the fuel electrode.

[0012] The present inventors have recently found that in a solid oxide fuel cell having an air electrode made of a perovskite oxide containing at least manganese, a layer in contact with the fuel electrode is located on the fuel electrode side. It has been found that the manganese content on the surface has a significant effect on the performance of the fuel cell, and that by controlling the manganese content, an excellent fuel cell can be obtained. The present invention is based on strong knowledge.

Accordingly, an object of the present invention is to provide a solid oxide fuel cell having excellent output performance and durability.

[0014] The fuel cell according to the present invention is a solid oxide fuel cell including at least an electrolyte, an air electrode, and a fuel electrode, wherein the air electrode includes at least manganese. The layer containing an oxide, wherein the manganese content in the surface of the layer in contact with the fuel electrode on the side of the fuel electrode is 0.34% by weight.

Brief Description of Drawings

FIG. 1 is a diagram showing a cross section of a cylindrical solid oxide fuel cell.

FIG. 2 is an enlarged cross-sectional view illustrating a basic configuration of a solid oxide fuel cell according to the present invention. The solid oxide fuel cell according to the present invention has a basic configuration including an air electrode support 1, an electrolyte 3, and an anode 4. In this figure, an air-side electrode reaction layer 5 as an embodiment of the air electrode is provided between the air electrode support 1 and the electrolyte 3, and between the electrolyte 3 and the fuel electrode 4. A porous layer 6 is provided. Air (oxygen) flows in the direction of the arrow inside the air support 1, and fuel gas (hydrogen, carbon monoxide, methane, etc.) flows in the direction of the arrow along the anode 4, and the air electrode and the fuel respectively flow. Make contact with poles.

[FIG. 3] is an enlarged cross-sectional view of a solid oxide fuel cell in which the fuel-side electrode reaction layer 4a is provided between the electrolyte 3 without the porous layer 6 and the fuel electrode 4 in the structure of FIG. It is.

FIG. 4 is an enlarged view of a solid oxide fuel cell in which the air-side electrode reaction layer 5 has a plurality of layers (5a, 5b) in the structure of FIG.

FIG. 5 is an enlarged view of a solid oxide fuel cell in which a porous layer 6 is provided between a fuel-side electrode reaction layer 4a and an electrolyte 3 in addition to the structure of FIG.

FIG. 6 is an enlarged view of a solid oxide fuel cell in which the air-side electrode reaction layer 5 has a plurality of layers (5a, 5b) in the configuration of FIG.

FIG. 7 is a diagram showing a battery configuration for measuring a reaction overvoltage for evaluating electrode characteristics. Detailed description of the invention

[0016] Eyes

The structure of the solid oxide fuel cell according to the present invention is not particularly limited as long as the structure and composition of the present invention described below are satisfied. For example, it may be either a flat plate type or a cylindrical type. The solid oxide fuel cell of the present invention is of the microtube type (outer diameter

10 mm or less, more preferably 5 mm or less). For example, the case of a cylindrical configuration is as follows. That is, FIG. 1 is a diagram showing a cross section of a cylindrical solid oxide fuel cell. In this solid oxide fuel cell, a strip-shaped interconnector 2, an electrolyte 3, and a fuel electrode 4 are provided on a cylindrical air electrode support 1 so as not to contact the interconnector 2 on the electrolyte 3. It is configured. When air (oxygen) flows inside the cathode support and fuel gas flows outside, oxygen ions are generated at the interface between the cathode and the electrolyte as shown below.

1/20 + 2e— → 〇 ² (1)

2

The oxygen ions reach the fuel electrode through the electrolyte. Then, at the fuel electrode near the electrolyte, the fuel gas and oxygen ions react to form water and carbon dioxide. These reactions are represented by the following equations.

H + 0 → H 0 + 2e (2)

twenty two

CO + O ² → CO + 2e— (3)

2

By connecting the fuel electrode 4 and the interconnector 2, electricity can be extracted to the outside.

FIG. 2 is an enlarged cross-sectional view illustrating a basic configuration of a solid oxide fuel cell according to the present invention. The solid oxide fuel cell according to the present invention has a basic configuration including an air electrode support 1, an electrolyte 3, and an anode 4. In FIG. 2, an air-side electrode reaction layer 5 as an embodiment of an air electrode is provided between the air electrode support 1 and the electrolyte 3, and between the electrolyte 3 and the fuel electrode 4. A porous layer 6 is provided. The air-side electrode reaction layer 5 and the porous layer 6 are not essential in the present invention, but are preferably provided.

Further, according to another preferred embodiment of the present invention, as shown in FIG. 3, in the solid oxide fuel cell according to the present invention, the fuel-side electrode reaction layer 4a as one embodiment of the fuel electrode has Provided May be.

According to another preferred embodiment of the present invention, as shown in FIG. 4, in the solid oxide fuel cell according to the present invention, the air-side electrode reaction layer 5 has a plurality of layers (5a, 5b). May be constituted by

Further, according to another aspect of the present invention, there is provided an aspect in which the above components are combined. For example, as shown in FIG. 5, a solid oxide fuel cell provided with a porous layer 6 between a fuel electrode 4 (a concept including a fuel-side electrode reaction layer 4a) and an electrolyte 3 is provided. Is performed. Further, according to another aspect, there is provided a solid oxide fuel cell in which the air-side electrode reaction layer has a plurality of layers in the configuration shown in FIG.

The present invention is characterized in that the content of manganese on the surface of the layer in contact with the fuel electrode on the fuel electrode side is 0.334% by weight.

Therefore, when the electrolyte is provided in contact with the fuel electrode, the content of manganese on the surface of the electrolyte on the fuel electrode side is 0.3 to 4% by weight. According to a preferred embodiment of the present invention, the manganese content on the anode side of the electrolyte is 0.6-3.5% by weight, more preferably 0.9-3% by weight. . In this embodiment, the manganese content on the air electrode side surface of the electrolyte is preferably less than about 10% by weight, more preferably less than 6% by weight. According to a further preferred aspect of the present invention, it is preferable that the content of manganese on the surface of the electrolyte on the air electrode side is larger than the content of the manganese component on the surface of the electrolyte on the fuel electrode side.

When a porous layer is provided between the fuel electrode and the electrolyte, the manganese content on the surface of the porous layer on the fuel electrode side is 0.3 to 4% by weight. is there. According to a preferred embodiment of the present invention, the manganese content on the surface of the porous layer on the fuel electrode side is preferably 0.6-3.5% by weight, more preferably 0.93% by weight. Further, according to a further preferred aspect of the present invention, it is preferable that the manganese content on the air electrode side surface of the electrolyte is larger than the manganese content on the fuel electrode side surface of the porous layer. ,.

In the present invention, “manganese content on the surface of the layer” in “content of manganese on the surface of the layer in contact with the fuel electrode on the side of the fuel electrode” refers to a depth of 3 μm from the surface of the fuel electrode. m Means the manganese content in the layer in contact with the fuel electrode within. In addition, the measurement may be either analysis from the fuel electrode side, formation of a cross section, and analysis from the cross section direction.

[0025] In the present invention, as described above, the manganese content on the surface on the fuel electrode side is controlled in the layer in contact with the fuel electrode. This manganese is considered to be diffused from perovskite oxide containing manganese constituting the air electrode during sintering during its production. By controlling the amount of this diffusion, it has excellent output characteristics. A solid oxide fuel cell that maintains its performance even after thermal cycling, that is, has excellent durability, has been realized. The reason why a good solid oxide fuel cell can be realized by controlling the amount of manganese is not clear, but the reason is as follows, provided that the present invention is not limited thereby. That is, if the amount of manganese is within the above range at the interface between the fuel electrode and the layer in contact with it, the adhesion between the two layers is greatly improved by sufficient sintering, and the electrolyte ensures good ionic conductivity. It is thought that this contributes to the improvement of its properties.

In the present invention, control of the amount of manganese on the fuel electrode side surface of the layer in contact with the fuel electrode can be realized by controlling the composition and physical configuration of the battery and the manufacturing conditions. Hereinafter, the elements constituting the solid oxide fuel cell according to the present invention, including the specific means for controlling the amount of manganese, will be described in detail.

[0027] Electrolysis

In the present invention, the electrolyte is a layer showing high conductivity of oxygen ions (O ² —) at high temperature and having no gas permeability, and a layer made of zirconium in which scandia and / or yttria are dissolved. Is preferably used. In the present specification, the ginoreconia in which scandia is dissolved is referred to as `` SSZ '', the zirconia in which scandia and yttria are dissolved is referred to as `` ScYSZ '' or `` SSZ / YSZ '', and the zirconia in which yttria is dissolved is referred to. Is called "YSZ".

According to a preferred embodiment of the present invention, the solid solution amount of scandia in SSZ, the total solid solution amount of scandia and yttria in ScYSZ, and the solid solution amount of yttria in YSZ are as high as about 312 mol%. A more preferable lower limit is preferably about 8 mol% because ionic conductivity can be realized. Further, according to a preferred embodiment of the present invention, oxygen ion conduction Ce〇, Sm〇, Gd〇, Yb O, Gd〇, Er〇, Nd O,

2 2 3 2 3 2 3 2 3 2 3 2 3

Eu〇, Ey〇, Tm O, Pr O, La O and Bi O force

2 3 2 3 2 3 2 3 2 3 2 3

At least one kind of oxide may be solid-dissolved in a total amount of about 5 mol% or less. Further, in order to enable sintering at a low temperature, Bi 2 O 3, Al 2 O 3, SiO 2 or the like may be added.

2 3 2 3 2

[0029] Further, according to a preferred embodiment of the present invention, when the electrolyte has a 3% diameter of 3 am or more and a 97% diameter of 20 µm or less of the crystal grain size on the fuel electrode side membrane surface, It preferably has a certain particle size distribution. By being in this range, an electrolyte having no gas permeability due to good sinterability and having good adhesion to the fuel electrode can be realized.

Here, the crystal grain size of the electrolyte surface on the fuel electrode side means a grain size distribution obtained by the Branimetric method. That is, first, a picture of the surface of the electrolyte is taken by SEM, and a circle with an approximate area (S) is drawn on this picture, and the number of particles in the circle, the force on the circumference, and the number of particles n Calculate the number of particles N per unit area.

G

N = (n + l / 2n) / (S / m ² )

G c i

Here, m is the magnification of the photograph. 1 / N force This is the area occupied by SI particles.

G

If the grain size is a circle-equivalent diameter, it is obtained as 2 / ^ (πΝ), and if it is a square, it is obtained as Ν.

G G

The

Further, in the present invention, the 3% diameter of the crystal grain diameter of the electrolyte corresponds to the third diameter when 100 crystal grain diameters are measured by the Branimetric method and arranged in ascending order of the particle diameter. The 97% diameter refers to the 97th particle diameter.

[0032] In the present invention, the fact that the electrolyte does not have gas permeability is specifically evaluated by providing a pressure difference between one side of the electrolyte and the opposite side thereof and measuring the gas permeation amount of N gas passing through the gap.

2

S power According to a preferred embodiment of the present invention, the electrolyte is a gas permeation amount Q is Q≤ 2. 8 X 10- ⁹ ms- ^ more preferably it is preferred instrument is a- ¹ Q≤2. 8 X 10- ms — ^ A— ¹

[0033] In the present invention, the thickness of the electrolyte may be appropriately determined.

From the viewpoint of durability and the like.

[0034] The electrolyte according to the present invention may be prepared from raw material powder of zirconium in which scandia and / or yttria are dissolved. Able to form appropriate crystal grain size without gas permeability In view of this, the BET value is 0.5-20 m ² g- ¹ , the 3% size is 0.1 / im or more, the 97% size is 2 μm or less, and the average particle size is 0. Raw material powder controlled to about 3-1 μm is more preferable. In the present invention, the BET value is preferably a value obtained by measurement using a fluid type specific surface area measuring apparatus Flow Soap Model 2300 manufactured by Shimadzu Corporation. The particle size distribution is preferably a value obtained by measurement using a laser diffraction type particle size distribution analyzer SA LD-2000 manufactured by Shimadzu Corporation. Further, the average particle diameter is preferably a value of a median diameter (50% diameter) obtained by using a laser diffraction particle size distribution analyzer SALD-2000 manufactured by Shimadzu Corporation.

[0035] The method for producing the electrolyte is not particularly limited, but a viewpoint of excellent mass productivity and low cost, a slurry coating method, a screen printing method, and a sheet bonding method are preferable.

[0036] The method for producing the raw material for the electrolyte is not particularly limited as long as it can uniformly dissolve the yttria and / or scandia, and the coprecipitation method is generally preferable.

[0037] According to another preferred embodiment of the present invention, the electrolyte is composed of at least two layers, a layer made of dinoreconia (YSZ) in which yttria is dissolved as a solid on the air-side electrode reaction layer side, and a fuel electrode side. A zirconia (SSZ) force layer in which scandia is dissolved as a solid solution may be provided, or vice versa.

[0038] Further, according to another preferred embodiment of the present invention, the electrolyte has at least a three-layer structure, and is formed by sequentially laminating a layer made of SSZ, a layer made of YSZ, and a layer made of SSZ. Can be.

Further, according to another preferred embodiment of the present invention, the electrolyte may have a different composition ratio of SSZ / YSZ. For example, the air electrode side of the electrolyte can be set to SSZ / YSZ = 3/1, and the fuel electrode side can be set to SSZ / YSZ = l / 3. Further, according to another example, SSZZYSZ = 3Zl, SSZ / YSZ = 1/3, and SSZ / YSZ = 3/1 may be changed toward the cathode side and the anode side. Here, SSZ / YSZ = 3/1 means solid solution in zircon

For example, 88molZrO—9Sc O—3Y へ

2 2 3 2 3 etc. correspond to this.

[0040] air electrode

In the present invention, the air electrode is an oxygen gas having a high electron conductivity in an air atmosphere. It is preferable to efficiently generate oxygen ions having high permeability. In the present invention, the air electrode is configured as an air electrode support having the function of the air electrode while maintaining the strength of the battery.

In the present invention, the air electrode contains a perovskite oxide containing at least manganese. According to a preferred embodiment of the present invention, the cathode is (La A) M

1— x x y n〇 (where A 〖Ca and Sr represent the x 〖0.15≤x≤0.3 and the y 〖0.97≤y≤l

Three

Lantern manga knight.

According to a preferred embodiment of the present invention, the air electrode or the air electrode support is made of a mixed conductive material in which a perovskite oxide containing manganese and nickel and an oxide having oxygen ion conductivity are uniformly mixed. It can be configured to be made of a conductive ceramic material. Preferable examples are, for example, (La A) (Mn Ni) O (where A represents Ca or Sr

1— x x y 1— z z 3

Satisfies 0.15≤x≤0.3, 0.97≤y≤l, 0.02≤z≤0.10.) And a mixture of SSZ with lanthanum manganite. Here, the proportion of the open bouskite-type oxide containing manganese and nickel is preferably 30 to 70% by weight. The air electrode has an appropriate pore size and porosity from the viewpoint of oxygen gas permeability, and preferably has a pore size of 0.5 / im or more and a porosity of 5% or more. Further, a composition having a high effect of suppressing the diffusion of manganese into the electrolyte is more preferable from the viewpoint of improving the durability performance.

According to a preferred embodiment of the present invention, the composition of the perovskite-type oxide containing manganese and nickel is (Ln A) (Mn Ni) O (where Ln is Sc, Y, La, Ce, Pr, N

1— x x y 1— z z 3

d, Pm, Sm, Eu, Gd, D, b, Dy, Ho, Er, Tm, Yb, and: represents one or more selected from the group consisting of Lu force, and 表し represents Ca or Sr , 0 · 15 ≤ x ≤ 0.3, 0.97 ≤ y ≤ 1, 0.02 ≤ z ≤ 0.10. When z is in the range of 0.02≤z≤0.10, the stability of solid solution is high. ぺ The effect of suppressing the diffusion of manganese in the lobskite structure to other electrodes is greatest. . When X satisfies 0.15≤x≤0.3, it is possible to secure good electronic conductivity and efficiently generate oxygen ions. Also, when y is in the range of 0.97≤y≤l, the amount of manganese in the perovskite structure is adjusted appropriately, and the excess lanthanum component absorbs moisture and changes to lanthanum hydroxide, and the stability of the material itself Is effectively prevented from decreasing. [0044] The oxide having oxygen ion conductivity constituting the air electrode is preferably an oxide containing at least dinorecon, a cerium-containing oxide, or a lanthanum gallate-based oxide. Further, as the oxide containing zirconia, SSZ, ScYSZ, and YSZ are more preferable.

[0045] The solid solution amount of scandia in the SSZ as the air electrode is preferably in the range of 3 12 mol%. Further, the total solid solution amount of scandia and yttria in ScYSZ is preferably in the range of 3 to 12 mol%. Furthermore, the solid solution amount of yttria in YSZ is in the range of 312 mol%. When the amount of solid solution of scandia or yttria becomes excessive, rhombohedral crystals are formed in addition to the cubic crystal phase, and oxygen ion conductivity is reduced, and scandia and yttria are expensive materials and oxygen ion conductivity is low. Care must be taken because it is not practical to form a solid solution to a lower point. SSZ and ScYSZ further include CeO, SmO, and Gd G

twenty three

At least one oxide selected from the group consisting of YbO and ErO is solid solution of 5 mol% or less.

3, 2, 3, 2 3

Let's go, let's go. Good oxygen ion conductivity can be ensured.

The cerium-containing oxide as the oxide having oxygen ion conductivity at the air electrode includes a general formula (CeO) Q Ο (where J is any one of Sm, Gd, and Y.

2 1-2X1 2 3 XI

05≤Χ1≤0.15). This compound requires a sintering temperature of 1500 ° C or more to form an electrolyte with low sinterability and no gas permeability, and the manganese-containing perovskite-type oxide is used for sintering at high temperatures. Manganese diffusion into the electrolyte is suppressed by the inclusion of nickel, which tends to increase the diffusion of manganese into the electrolyte.

[0047] Further, as the lanthanum gallate-based oxide which is an oxide having oxygen ion conductivity at the air electrode, a general formula La D Ga E〇 or La D Ga E L O (where D

1— a a 1— b b 3 1— a a 1— b— c b c 3

Represents one or more of Sr, Ca, Ba, E represents one or more of Mg, Al, In, and L represents one or more of Co, Fe, Ni, Cr) Are preferably used. When co-sintered with a perovskite-type oxide containing manganese, mutual diffusion tends to occur and manganese tends to be easily diffused.However, by including nickel, the diffusion of manganese can be effectively suppressed. .

[0048] 'Fire basket

In the present invention, the fuel electrode is usually used as a fuel electrode of a solid oxide fuel cell. It may be. That is, the fuel electrode reacts with the fuel gas in the fuel gas atmosphere of the solid oxide fuel cell, which has moved through the electrolyte, which has high electron conductivity and high fuel gas permeability, to become water and carbon dioxide. It is only necessary that the reaction be carried out efficiently.

[0049] According to a preferred aspect of the present invention, the fuel electrode is preferably formed by sintering nickel oxide and zirconia. Nickel oxide is reduced in a fuel gas atmosphere to become nickel, and exhibits catalytic activity and electronic conductivity.

[0050] According to a preferred embodiment of the present invention, it is preferable to use nickel oxide and a dinoreconia (NiOZYSZ) obtained by dissolving yttrium as a fuel electrode. This is because this substance has high electronic conductivity and can reduce IR loss. The Ni〇 / YSZ ratio of 50/50 to 90/10 by weight is preferable because high electronic conductivity can be realized and durability performance can be effectively prevented from lowering due to aggregation of Ni particles.

According to a preferred embodiment of the present invention, as a material of the fuel electrode, zirconia in which Ni / SSZ or NiO / calcium is dissolved (hereinafter, referred to as NiO / CSZ) can be exemplified. YSZ is cheaper than SSZ, so YSZ is more preferred. CSZ is even cheaper than YSZ, so NiO / CSZ is the most preferred in terms of cost. Ni / CSZ also becomes Ni / CSZ under the fuel gas atmosphere of the solid oxide fuel cell.

[0052] The method of preparing the fuel electrode raw material is not particularly limited as long as the fuel electrode materials such as NiO / SSZ and NiO / YSZ are uniformly mixed, and examples thereof include a coprecipitation method and a spray drying method. .

It is preferable to provide a fuel-side electrode reaction layer between the electrolyte and the fuel electrode in order to make the reaction between oxygen ions and the fuel gas efficient, but details of the fuel-side electrode reaction layer will be described later. I do.

[0054] Ki, Tsukuda J

According to a preferred embodiment of the present invention, at the interface between the air electrode and the electrolyte,

1/20 + 2e— → 〇 ² —

2

An air-side electrode reaction layer should be provided between the air electrode and the electrolyte to promote the reaction of Is preferred.

In the present invention, the air-side electrode reaction layer preferably has high oxygen ion conductivity.

Further, it is more preferable that the composition further has electronic conductivity because the above reaction can be further promoted. Further, it is preferable that the material has a low coefficient of thermal expansion with the electrolyte and a material having low reactivity with the air electrode and good adhesion.

In view of the above, according to a preferred embodiment of the present invention, as a preferred material for the air-side electrode reaction layer, a lanthanum manganese represented by LaAMnO (where A is Ca or Sr)

Three

And a layer formed by mixing SSZ uniformly. Here, according to a preferred embodiment of the present invention, from the viewpoints of electron conductivity at 700 ° C. or higher, stability of the material, and the like, when this material is expressed as (La Ax) MnO, 0.15≤x≤0.3, 0.97≤y≤l¾r lx y 3

It is preferable that the composition has a satisfactory composition. By being in this composition range, high electron conductivity can be secured, lanthanum hydroxide is prevented from being generated, and a high-output fuel cell can be realized.

According to a preferred embodiment of the present invention, the lanthanum manganite is dissolved in Ce, Sm, Gd, Pr, Nd, Co, Al, Fe, Cr, Ni, etc., in addition to Sr or Ca. Even if it is good. In particular, those having the composition represented by (La, A) (Mn, Ni) O in which Ni is dissolved in solid form are La Zr O

It is preferable because it can only suppress the formation of an insulating layer called lanthanum zirconate represented by 322 and can suppress the diffusion of manganese.

[0058] The SSZ of the air-side electrode reaction layer in the present invention further includes Ce S, Sm〇, GdO, Bi

2 2 3 2 3

O or the like may be dissolved in a solid solution of about 5 mol% or less. Also, two or more kinds may be dissolved. this

twenty three

The solid solution of these materials is preferable because improvement in oxygen ion conductivity can be expected. According to a preferred embodiment of the present invention, the solid solution amount of scandia in the SSZ of the air-side electrode reaction layer is about 312 mol%, more preferably about 812 mol% from the viewpoint of oxygen ion conductivity.

According to a preferred embodiment of the present invention, the air-side electrode reaction layer is composed of lanthanum manganite, S SZ, and a general formula (Ce〇) (BO) (where B is any one of Sm, Gd, and Y) Or X

2 1-2X 2 3 X

Satisfies 0.05 ≤ される ≤ 0.15), which may be a layer uniformly mixed with cerium oxide represented by the formula: Presence of cerium oxide Thus, suppression of the reaction between the air electrode and the electrolyte is expected. The mixing amount of cerium oxide is

About 3-30 wt% of the total power, which is preferable from the viewpoint of suppressing the reaction between the air electrode and the electrolyte and ensuring the adhesion between the two.

[0060] According to another preferred embodiment of the present invention, the air-side electrode reaction layer comprises a perovskite oxide containing manganese and nickel oxide, an oxide containing dinoreconia, a cerium oxide, or lanthanum and gallium. It is preferable to be made of a mixed conductive ceramic with a perovskite-type oxide containing, and to have open pores communicating with each other.

Here, the perovskite-type oxide containing manganese and nickel is preferably (Ln

One

A) (Mn Ni) 〇 (where, is Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd,

—X x y 1— z z 3

Group power consisting of Tb, Dy, Ho, Er, Tm, Yb, and Lu Any four or more of the selected powers, A represents either Ca or Sr, and X represents 0.15 ≤x≤0.3, y satisfies 0.97≤y≤l, and z satisfies 0.02≤z≤0.10).

[0062] The oxide containing zirconia preferably refers to zirconia in which scandia is dissolved or zirconia in which scandia and yttria are dissolved.

[0063] Further, cerium oxide is preferably a compound of the formula (Ce〇) Q Q) (where J is Sm

2 1-2X1 2 3 XI

, Gd, or Y, and XI satisfies 0 · 05≤Χ1≤0.15).

[0064] In this embodiment, the content of the perovskite oxide containing manganese and nickel in the air-side electrode reaction layer is preferably about 30 to 70% by weight.

[0065] Further, according to another preferred embodiment of the present invention, the air-side electrode reaction layer is composed of at least two layers: a first layer on the air electrode side and a second layer on the electrolyte side. It's preferable.

[0066] In this embodiment, it is preferable that the first layer is a layer in which an oxide having electron conductivity and an oxide having oxygen ion conductivity are uniformly mixed and has open pores communicating with each other. .

Here, the oxide having electronic conductivity is preferably an oxide having electronic conductivity and being stable in the air atmosphere of a solid oxide fuel cell. More specifically, Sr or Ca is preferably solidified. Melted Lantern manga night. Considering that the diffusion of manganese into the electrolyte is small, and that the electron conductivity is high, (La A) MnO (where A represents Ca or Sr,

1—

x satisfies 0.15≤x≤0.3, and y satisfies 0.97≤y≤1). The lanthanum manganite may be a solid solution of Ce, Sm, Pr, Nd, Co, Al, Fe, Ni, Cr and the like. In particular, it is preferable to dissolve Ni. As a solid solution of Ni, (La A) (Mn Ni) 〇 (where A = Ca or Sr

1— x x y 1— z z 3

The displacement force, which is 0.15≤x≤0.3, 0.97≤y≤l, 0.02≤z≤0.10) is the force S preferred.

[0068] Examples of the oxide having oxygen ion conductivity in the first layer include oxygen ion conductivity, which may be stable as long as it is stable in an air atmosphere of a solid oxide fuel cell. Examples thereof include SSZ, ScYSZ, YSZ, cerium-containing oxides, and perovskite-type oxides containing at least lanthanum and gallium (hereinafter referred to as lanthanum gallate-based oxides).

[0069] The solid solution amount of scandia in the SSZ as the first layer is preferably in the range of 3 to 12 mol%. Further, the total solid solution amount of scandia and yttria in ScYSZ as the first layer is preferably in the range of 3 to 12 mol%. Further, the preferred amount of yttria in YSZ for the first layer is in the range of 3 to 12 mol%. If the amount of solid solution of scandia or yttria becomes excessive, the crystal phase will generate rhombohedral crystals in addition to cubic, and oxygen ion conductivity will decrease.Scandia and yttria are expensive materials and oxygen ion conductivity. It should be noted that it is not practical to form a solid solution to the point where In addition, SSZ and ScYSZ include a small amount selected from Ce ら, Sm〇, Gd O Yb O, and Er O forces.

2 2 3 2 3, 2 3, 2 3

At least one kind of oxide may be dissolved in 5 mol% or less. Good oxygen ion conductivity can be ensured.

[0070] The cerium-containing oxide as the first layer is represented by the general formula (Ce〇) Q〇)

2 1-2X1 2 3 XI

(However, J is any one of Sm, Gd, and Y, and is represented by 0.05 ± 1≤ 0.15).

[0071] Further, as the lanthanum gallate-based oxide as the first layer, the general formula La D Ga

1— a a 1-b

E〇 or La D Ga EL〇 (where D is one or more of Sr, Ca, Ba, E b 3 1 aa 1— b— cbc 3 Is preferably one or more of Mg, Al, and In, and L is one or more of Co, Fe, Ni, and Cr).

[0072] As described above, the oxide having preferable electron conductivity and the oxide having oxygen ion conductivity have been exemplified as the first layer. However, the first layer has both electron conductivity and oxygen ion conductivity. May be. Examples thereof include a lanthanum cobaltite-based oxide which is an oxide containing at least lanthanum and cobalt.

[0073] It is preferable that the second layer has at least oxygen ion conductivity, has an action of suppressing the diffusion of a manganese component into the electrolyte, and has open pores communicating therewith.

Here, it is preferable to have at least oxygen ion conductivity in order to efficiently supply oxygen ions, which are considered to be mainly generated in the first layer, to the electrolyte. Further, it is preferable to have an action of suppressing the diffusion of the manganese component into the electrolyte because it is possible to suppress the development of electronic conductivity in the electrolyte and the particles on the fuel electrode side of the electrolyte generated by the improvement in sinterability are large. This is because it is possible to suppress a decrease in the adhesion to the fuel electrode, which is caused by too much bending. Further, it is preferable to have open pores communicating with each other, because if the gas does not have gas permeability, the manganese component diffused from the first layer and the air electrode is efficiently diffused. The point that controls the amount of manganese diffusion is the microstructure in the second layer, and it is particularly important to optimize the pore size, porosity, and thickness. The pore size is preferably 0.1 to 10 μΐη, the porosity is preferably 3 to 40%, and the thickness is preferably 5 to 50 / im.

In this embodiment, as the second layer, a material having high oxygen ion conductivity and low sinterability, that is, a material that does not easily diffuse manganese into the electrolyte is preferable for the above reason. Further, a material having an action of absorbing manganese diffused from the air electrode is preferable. From this viewpoint, SSZ and cerium-containing oxides are representative. Although the sinterability is higher than that of SSZ, the use of ScYSZ is also preferable from the viewpoint of improving the adhesion between the first layer and the electrolyte. It is preferable that manganese diffused from the air electrode has an action of absorbing manganese. When manganese enters the second layer, electronic conductivity is developed in the second layer, and oxygen ions are generated similarly to the first layer. Can be generated. This effect is an advantageous aspect of the present invention in that higher output performance can be realized. [0076] In this embodiment, the SSZ and the cerium-containing oxide as the second layer may be the same as those described in the first layer. Also, ScYSZ may be the same as that of the first layer, but the ratio of scandia to the total amount of scandia and yttria in ScYSZ is preferably 20 mol% or more. If the scandium is too small, the effect of suppressing the diffusion of manganese is reduced. In addition, ScYSZ contains Ce〇 and Sm O

twenty two

, Gd〇 Yb〇 and Er〇 force At least one oxide selected is 5 mol% or less

3 2 3, 2 3, 2 3

It may be dissolved.

[0077] Therefore, as an embodiment in which the air-side electrode reaction layer of the present invention is composed of two layers,

The first layer is a mixture of a perovskite-type oxide containing manganese and zirconia in which scandia and / or yttria are dissolved and has open pores communicating with each other. Zirconia in which scandia is dissolved as a solid solution having a higher porosity than the electrolyte,

The first layer is a mixture of a perovskite-type oxide containing manganese and a cerium-containing oxide and having open pores communicating with each other, and the second layer is a solid solution of scandia. A zirconia which has a higher porosity than the electrolyte,

The first layer is a mixture of a perovskite-type oxide containing manganese and a perovskite-type oxide containing lanthanum and gallium and having open pores communicating with each other. A zirconia in which a solid solution is formed, having a porosity larger than that of the electrolyte;

The first layer is a perovskite-type oxide containing lanthanum and cobalt and has open pores communicating with each other, and the second layer is dinorecoure in which scandia is dissolved as a solid solution. Also having a large porosity,

The first layer is a mixture of a perovskite-type oxide containing manganese and zirconia in which scandia and z or yttria are dissolved, and has a continuous open pore; The second layer is made of cerium oxide having a higher porosity than the electrolyte.

Is provided. Further, according to a preferred embodiment of the present invention, in the aspect in which the air-side electrode reaction layer has two layers, the diameter dl of the pores of the air electrode and the diameter d2 of the pores of the first layer In addition, it is preferable to satisfy the relationship of the pore diameter d3 of the second layer and the force dl>d2> d3 from the viewpoint of realizing a fuel cell having excellent power output characteristics.

Further, according to another preferred embodiment of the present invention, when the air-side electrode reaction layer has two layers, the porosity al of the air electrode, the porosity a2 of the first layer, It is preferable that the porosity a3 of the second layer and the porosity a4 of the electrolyte satisfy the relationship of al≥a2≥a3> a4.

[0080] The thickness of the first layer and the thickness of the second layer may be determined as appropriate, but preferably the thickness of the second layer is 550 µm, and the thickness of the first layer is Is 550 μm.

[0081] Porous layer

According to a preferred embodiment of the present invention, a porous layer is provided between the fuel electrode and the electrolyte. In the present invention, this porous layer is made of a fluorite-type oxide containing zirconia, has a thickness of 5-40 / im, and has a porosity larger than that of the electrolyte. . In the present invention, as described above, the manganese content on the surface of the porous layer on the fuel electrode side is 0.3 to 4% by weight. .

Further, according to a preferred embodiment of the present invention, the content of the manganese component on the surface of the porous layer on the fuel electrode side is preferably 0.6 to 3.5% by weight, more preferably 0 to 3.5% by weight. 9-3% by weight.

[0083] In the present invention, the porous layer functions not only to suppress the diffusion of manganese to the fuel electrode, but also to efficiently move oxygen ions that have moved the electrolyte to the fuel electrode. . From this viewpoint, the porous layer preferably has high oxygen ion conductivity. It is also important to control the thickness of the porous layer so that manganese from the electrolyte is not diffused to the anode and the output performance is not reduced by the resistance of the material itself. According to a preferred embodiment of the present invention, the thickness of the porous layer is preferably 5 to 40 zm. Further, the porous layer preferably has a porosity of 330% from the viewpoint of output performance and durability performance, and the pore diameter of the porous layer is preferably about 0.05 to 2 zm. On the other hand, to prevent H gas from reaching the electrolyte surface from the fuel electrode side,

2 There are no holes that lead to, and things are preferred.

According to a preferred embodiment of the present invention, the porosity al of the electrolyte, the porosity a2 of the porous layer made of the fluorite-type oxide, and the porosity a3 of the fuel electrode are & 1 <& 2. <It is preferable to satisfy the relationship of & 3.

[0085] According to a preferred embodiment of the present invention, the fluorite-type oxide containing zirconia constituting the porous layer is stable under a fuel gas atmosphere of a solid oxide fuel cell and has an oxygen ion conductivity. Higher materials are preferred SSZ, ScYSZ, and YSZ are preferred. These SSZ, ScYSZ, and YSZ may be the same as those constituting the air-side electrode reaction layer except for physical properties required for the porous layer. Further, the preferred embodiment may be the same.

[0086] Unsho J

According to a preferred embodiment of the present invention, it is preferable to provide a fuel-side electrode reaction layer between the electrolyte and the fuel electrode in order to efficiently perform the reaction at the fuel electrode and improve the output performance. In the present invention, since the fuel-side electrode reaction layer is one mode of the fuel electrode, the meaning of the term “layer in contact with the fuel electrode” means that the fuel-side electrode reaction layer is provided. This means a layer in contact with the fuel-side electrode reaction layer.

In the present invention, as the fuel-side electrode reaction layer, NiO / SSZ or Ni / SSZ, which has both excellent electron conductivity and oxygen ion conductivity, is preferably used. Here, NiO is reduced in a fuel atmosphere to become Ni, and the fuel-side electrode reaction layer becomes Ni / SSZ.

[0088] According to a preferred embodiment of the present invention, the ratio of NiO / SSZ is preferably 10 / 90-50 / 50 by weight, because good electronic conductivity and oxygen ion conductivity can be realized.

[0089] In addition, the solid solution amount of scandia in the SSZ constituting the fuel-side electrode reaction layer is preferably about 3 to 12 mol% because the reaction in the fuel electrode having high oxygen ion conductivity can be promoted. Masire, This SSZ is further divided into Ce さらに, Sm〇, Gd〇, Bi〇

One, two or more of 2 2 3 2 3 2 3 may be dissolved in 5 mol% or less. By dissolving them, not only the improvement of oxygen ion conductivity but also the improvement of electron conductivity under fuel gas atmosphere can be expected.

According to a preferred embodiment of the present invention, NiO, SSZ, and cerium are used as the fuel-side electrode reaction layer. A layer in which oxides are uniformly mixed at a predetermined weight ratio (hereinafter, NiO / SSZ / cerium oxide) can be preferably used. This layer has the advantage of high oxygen ion conductivity and high electron conductivity in a fuel gas atmosphere. Ni〇 is reduced to Ni in a fuel gas atmosphere, and this layer becomes Ni / SSZZ cerium oxide. Here, the cerium oxide is not particularly limited as long as it is an oxide containing cerium, but the general formula (CeO)

2 1-2

(B〇) (where B represents one of Sm, Gd, or Y, and X is 0.05 ± ≤

X 2 3 X

(Which satisfies 0.15) is preferable because it can realize high oxygen ion conductivity.

[0091] Interconnector

The interconnector of the solid oxide fuel cell according to the present invention has high electronic conductivity, no gas permeability, and redox atmosphere in the air atmosphere and fuel gas atmosphere at the power generation temperature of the solid oxide fuel cell. Those that are stable to are preferred. From this viewpoint, the use of lanthanum chromite is preferred.

[0092] Since lanthanum chromite is difficult to sinter, the firing temperature of solid oxide fuel cells

(1500 ° C or less), it is difficult to produce an interconnector without gas permeability. It is preferable to use Ca, Sr, or Mg as a solid solution to improve sinterability. Solid solution of Ca from the point that a membrane without gas permeability can be produced at the same temperature as when sintering other electrodes such as the electrolyte of a solid oxide fuel cell with the highest sinterability. Preferably.

[0093] The greater the solid solution amount of lanthanum chromite in which Ca is dissolved in the interconnector is, the higher the electronic conductivity is, but the stability of the material may be reduced. I like it.

[0094] According to a preferred embodiment of the present invention, (La Ax) is provided between the air electrode and the interconnector.

1—x y

Mn〇 (where, represents Sr or f or Ca, xf is 0.15≤x≤0.3, yf is 0.97≤v≤l

Three

And a dense pre-coat layer may be provided. This precoat layer is advantageous because the calcium chromate component, which is a sintering aid component of lanthanum chromite in which Ca is dissolved, can be effectively prevented from diffusing into the air electrode. Here, the dense pre-coat layer means a pressure between one side of the pre-coat layer and the opposite side. When provided with a force difference, it is evaluated in a gas permeation quantity of transmitted therebetween, gas permeation Q≤1.4 X 10 - preferably those at ^{7 ms-} ^ a- ¹ or more.

[0095] When the solid oxide fuel cell has a flat plate shape, the interconnector is called a separator, and the role is the same as that of the interconnector. In the case of a separator, a heat-resistant metal such as ferrite stainless steel may be used.

[0096] Eye {book> 开

The solid oxide fuel cell according to the present invention can be manufactured by a suitable manufacturing method in consideration of its shape and the like. In the case of a cylindrical type as shown in FIG. 1, it can be manufactured as follows.

[0097] First, an air electrode portion serving as a support is mixed with a perovskite-type oxide containing at least manganese as a raw material and other components, preferably together with a binder, and the mixture is extruded and molded by a molding method. Then, after removing the binder at a temperature of about 300 to 500 ° C, baking is performed at about 1400 to 500 ° C to obtain a high strength porous air electrode support. As the firing method, there are a hanging firing method and a horizontal firing method, but a horizontal firing method is preferable.

Subsequently, an air-side electrode reaction layer, an electrolyte, an interconnector, and a fuel electrode are formed on the surface of the obtained air electrode support. As a method for forming these electrodes, a wet method is preferable from the viewpoint of cost. As a wet method, a dipping method in which a slurry is prepared from a raw material powder, a binder, and a solvent, and immersed in the slurry to form an electrode, and a screen that forms a film through a screen using a paste having a higher viscosity than the slurry Examples of the method include a printing method and a sheet bonding method in which a sheet formed on another substrate such as a pet film is attached to the cell surface. In the case of the cylindrical cell shown in Figure 1, the air-side electrode reaction layer and the electrolyte are interconnected and the fuel electrode are preferably selected by the diving method. For this, a screen printing method or a sheet bonding method, which is a masking-less method, is preferable.

[0099] After removing the binder at a temperature of about 300 to 500 ° C, the cell formed by the above method is sintered at a temperature of about 1300 to 1500 ° C below the temperature of the air electrode support. Is preferably performed. There are two firing methods: a sequential firing method in which each layer is fired, and a co-firing method in which several layers are fired simultaneously. Co-firing from a cost perspective Although a synthesis method is preferable, in the present invention using a perovskite-type oxide containing at least manganese as the air electrode support, there is a possibility that the output performance may be significantly reduced due to the diffusion of manganese. There is also.

[0100] Co-firing with the air electrode molded body is also possible. However, in the case of the air electrode support firing, firing is performed at a higher temperature than the other electrodes. It is good.

Example

[0101] The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples.

Test methods for various physical properties, performance, and the like in Examples were as follows.

[0102] Measurement of crystal grain size of lightning film

The surface of the electrolyte membrane was observed by SEM using S-4100 manufactured by Hitachi, Ltd., and the fuel electrode side surface of the electrolyte was photographed at a magnification of 300 times. Furthermore, the particle size distribution of the particles was calculated by the Branimetric method using the photographed images. The average crystal grain size was also measured. That is, a circle with a known area (A) is drawn on a photograph, and the number of particles N per unit area is obtained from the number of particles n in the circle and the number of particles n exerted on the circumference by the following formula.

N = (n + l / 2n) / (A / m ² )

G c i

Where m is the magnification of the picture. The area occupied by 1 / N force particles

G

Is equivalent to a circle with a diameter of 2 / (π 、), and one side of a square is 1 / Ν.

G G

The 3% diameter in the particle size distribution on the film surface refers to the third equivalent particle size when 100 crystal grain sizes are measured by the Branimetric method and arranged in ascending order of particle size. The diameter refers to the particle size corresponding to the 97th. It should be noted that even when particles seemed to be joined by sintering, if a grain boundary was observed, the measurement was performed by regarding the particles as separate particles.

[0103] Gas leak test

Before the power generation test, nitrogen gas was flown into the inside of the cathode support, a pressure of IMPA was applied from inside the cathode, and the amount of gas permeated through the electrolyte was measured. This was used to evaluate whether the electrolyte had no gas permeability and was a membrane.

[0104] Power generation test A power generation test was performed using the prepared battery (fuel electrode effective area: 150 cm ² ). The operating conditions were as follows.

Fuel: (H + 11% HO): N = 1: 2

2 2 2

Oxidant: Air

Power generation temperature: 800 ° C

Current density: 0.3 Acm— ²

[0105] Hisashi exam

After holding for 1000 hours under the same conditions as in the power generation test, the temperature was lowered to room temperature with the current density lowered to OAcm- ^2, and then the temperature was raised again to 800 ° C and held for 500 hours under the same conditions. After the temperature was lowered to room temperature while the current density was lowered to OAcm- ² again, the temperature was raised to 800 ° C and maintained for 500 hours under the same conditions. In this way, a total of 2,000 hours of durability tests including two heat cycles were performed.

[0106] Composition analysis of thunder solution

Using a battery fabricated under the same conditions as the power generation test battery, the manganese content on the fuel electrode side surface of the electrolyte was examined. The manganese content was measured using a Shimadzu electron beam microanalyzer EPMA-8705 manufactured by Shimadzu Corporation. The measurement conditions were as follows.

Accelerating voltage: 15kW

Irradiation current: 50nA

Dispersion crystal: LiF

Analysis line: ΜηΚ α-ray (2 · 103 A)

[0107] Porosity

The cell was cut, and the cut surface from the air electrode to the fuel electrode was polished until a mirror surface appeared. Electrolyte force A cross-sectional photograph of the fuel electrode was taken with an SEM, and the voids and particles were traced on a transparent film with different colors. It was determined by subjecting the color-coded film to image processing and calculating the ratio of voids.

[0108] Pores

The pore diameter was determined by the following method. Disconnect the battery and cut from the air electrode to the fuel electrode Polish the surface until a mirror surface appears. From the air electrode to the electrode reaction layer, take a cross-sectional photograph with SEM, and trace the gaps and particles on a transparent film by color coding. The size of the void is measured. For example, when the void is equivalent to a circle, the diameter is the pore diameter, and when the void is equivalent to a square, the length of one side is calculated as the pore diameter. The pore diameter of 0.1 to 10 zm means that the pore diameter was measured in the third to 97th range when 100 pore diameters were measured by the above-described method and arranged in ascending order of diameter. It refers to the one corresponding to the second pore size. That is, it means that the pore diameter in the range of 3% to 97% and corresponding to the 50% diameter is 0.1 0μΐη.

[0109]

(1) Preparation of cathode support

Lanthanum manganite with Sr as solid solution represented by La Sr MnO composition

0.75 0.25 3

It was. After preparation by a coprecipitation method, a heat treatment was performed to obtain an air electrode raw material powder. The average particle size was 30 / m. A cylindrical molded body was produced by an extrusion molding method, and was further calcined at 1500 ° C to obtain an air electrode support.

(2) Preparation of air-side electrode reaction layer

La Sr Mn Ni O / 90mol% ZrO -lOmol as air side electrode reaction layer

0.75 0.25 0.95 0.05 3 2

% Sc O = 50/50 was used. Nitrate of La, Sr, Mn, Ni, Zr, and Sc

twenty three

After the solution was prepared so as to have the above composition, coprecipitation with oxalic acid was performed. Further, heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 μΐη. 40 parts by weight of this powder are 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed into a film on the above-mentioned air electrode support (outside diameter: 15 mm, wall thickness: 1.5 mm, effective length: 400 mm) by a slurry coating method, and then sintered at 1400 ° C. The thickness was 20 μm.

(3) Preparation of electrolyte slurry:

The electrolyte was 90 mol% ZrO-10 mol% ScO. Aqueous nitrate solution for each of Zr and Sc And coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 μΐη. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 140 mPas.

[0112] (4) Preparation of electrolyte

The prepared slurry was formed into a film on the air-side electrode reaction layer by a slurry coating method and fired at 1400 ° C. The thickness of the obtained electrolyte was 30 × m. The portion where the interconnector film is formed in a later step is masked so that the film is not applied.

(5) Preparation of slurry for fuel-side electrode reaction layer

The fuel-side electrode reaction layer was NiO / 90 mol% ZrO-10 mol% ScO. Ni

2 2 3, Zr and

After each Sc was prepared to have the above-mentioned composition using a nitrate aqueous solution, coprecipitation with oxalic acid was performed. Further, after heat treatment was performed to control the particle size, a raw material was obtained. The composition of the fuel-side electrode reaction layer is Ni〇 / 90mol% Zr〇_10mol% Sc O = 20/80, 50/50

2 2 3

Types were made. The average particle diameter was 0.5 μΐη in all cases. 100 parts by weight of this powder, 500 parts by weight of an organic solvent (ethanol), 10 parts by weight of Noku Inda (ethyl cellulose), 5 parts by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing 1 part by weight and 5 parts by weight of plasticizer (DBP), the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 70 mPas.

(6) Slurry preparation of fuel electrode:

The fuel electrode was NiOZ90mol% ZrO-10mol% YO = 70/30. Ni

Each of the aqueous solutions of 222, Zr, and Y was mixed so as to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further, after heat treatment was performed to control the particle size, a raw material was obtained. The average particle size was 2 xm. 100 parts by weight of this powder, 500 parts by weight of an organic solvent (ethanol), 20 parts by weight of a binder (ethyl cellulose), 5 parts by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) 1 part by weight, plasticizer (DBP) 5 parts by weight After mixing the parts, the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 250 mPas.

(7) Preparation of fuel electrode

The electrolyte prepared in (4) above is masked so that the effective area becomes 150 cm ^2, and the slurry on the fuel-side electrode reaction layer is first coated on the electrolyte by a slurry coating method to obtain ΝΪΟ / 90 mol% ZrO—10 mol% Sc〇 (average particle size) = 2θΖ80 (0.5 μm), 50/50 (0.5

2 2 3

μm). The thickness (after firing) was 10 μm. A fuel electrode slurry was formed thereon by a slurry coating method. The thickness (after firing) was 90 zm. Further, firing was performed at 1400 ° C.

(8) Fabrication of interconnector:

La with a Ca solid solution represented by the composition of the interconnector La Ca CrO

0.80 0.20 3

Chromite. The raw material powder was prepared by spray pyrolysis and then heat-treated. The average particle size of the obtained powder was 1 μm. 40 parts by weight of the powder are 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) 1 After that, the mixture was mixed sufficiently with the mixture and stirred sufficiently to prepare a slurry. The viscosity of this slurry was 100 mPas. An interconnector was formed by a slurry coating method and fired at 1400 ° C. The thickness after firing was 40 μm.

Example A1-2

A solid oxide fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1360 ° C.

[0118] Example Al_3

A fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1380 ° C.

[0119] Example Al_4

A fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1420 ° C.

[0120] Example Al_5 A fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1440 ° C.

[0121] Comparative example A1-1

A fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1340 ° C.

[0122] Comparative example A1-2

A fuel cell was obtained in the same manner as in Example 1, except that the firing temperature of the electrolyte was 1460 ° C.

Example 2 Electrolyte Force A fuel cell which is a layer composed of YSZ. Examples A1-1 and A-1 were the same except that the electrolyte composition was 90 mol% Zr〇_10 mol% YO.

2 2 3

Similarly, a fuel cell was obtained.

Example A2-2

The composition of the electrolyte is 90 mol% Zr〇-10 mol% YO, and the sintering temperature of the electrolyte is 135 mol%.

2 2 3

A fuel cell was obtained in the same manner as in Example A1-1 except that the temperature was 0 ° C.

Example A2—3

The composition of the electrolyte is 90 mol% Zr〇-10 mol% YO, and the firing temperature of the electrolyte is 138%.

2 2 3

Example A2—4

The composition of the electrolyte is 90 mol% Zr〇 -10 mol% YO, and the sintering temperature of the electrolyte is 141 mol%.

2 2 3

[0127] Example A2_5

The composition of the electrolyte is 90molQ /. Zr〇 -10 mol% Y O, and the sintering temperature of the electrolyte was 142

2 2 3

[0128] Comparative example A2-1

The composition of the electrolyte is 90molQ /. Zr〇 -10 mol% Y O, and the sintering temperature of the electrolyte is 133

2 2 3

[0129] Comparative Example A2-2 The composition of the electrolyte is 90 mol% Zr〇-10 mol% YO, and the firing temperature of the electrolyte is

2 2 3

A fuel cell was obtained in the same manner as in Example Al-1, except that the temperature was 0 ° C.

Example 3: Fuel cell in which the electrolyte is a layer composed of SSZZYSZ

Example A3_l

Except that the composition of the electrolyte is 90 mol% Zr〇 -5 mol% ScO -5 mol% YO

2 2 3 2 3

A fuel cell was obtained in the same manner as in Example A1-1.

[0131] Example A3_2

The composition of the electrolyte is 90 mol% ZrO -5 mol% ScO -5 mol% YO,

2 2 3 2 3

A fuel cell was obtained in the same manner as in Example Al-1, except that the firing temperature was 1350 ° C.

[0132] Example A3_3

The composition of the electrolyte is 90 mol% ZrO -5 mol% ScO -5 mol% YO,

2 2 3 2 3

A fuel cell was obtained in the same manner as in Example Al-1, except that the firing temperature was 1380 ° C.

Example A3—4

The composition of the electrolyte is 90 mol% ZrO_5 mol% ScO_5 mol% YO,

2 2 3 2 3

A fuel cell was obtained in the same manner as in Example Al-1, except that the firing temperature was 1420 ° C.

Example A3—5

The composition of the electrolyte is 90 mol% ZrO_5 mol% ScO_5 mol% YO,

2 2 3 2 3

A fuel cell was obtained in the same manner as in Example Al-1, except that the firing temperature was 1,430 ° C.

[0135] The fuel cell obtained as described above was subjected to a particle size distribution, a gas leak test, a power generation test, and a durability test. The results were as shown in the following display.

[table 1]

3% diameter 9 7% diameter Average crystal grain size Mn amount Gas permeation amount

(jm) (m) (wt%) (xlO '^ ms-' Pa ' ¹ ) Example A 1 3 8 5 0.9 3.5 Example A 2 3 5 4 0.3 25.5 Example A1-3 3 7 4.5 0.6 12.7 Example A 1-4 3 12 7.5 1.5 3.0 Example A 1-5 4 20 12 2.9 3.7 Comparative example Al-1 1 4 2 0.1 320 Comparative example A1-2 5 26 15 4.3 5.5 [Table 2]

[Table 3]

[Table 4]

Initial potential After 1000 hours After 1500 hours After 2000 hours (V) (V) (V) (V) Example A2- 1 0.58 0.58 0.58 0.58 Example A2-2 0.57 0.57 0.57 0.57 Example A2-3 0.58 0.58 0.58 0.58 Example A2-4 0.58 0.58 0.58 0.58 Example A2-5 0.57 0.57 0.57 0.57 Comparative example A2- 1 0.42 0.41 0.40 0.39 Comparative example A2- 2 0.56 0.56 0.55 0.54

[Table 5]

[Table 6]

After 1000 hours 脚 ¾5ς, l¾l

(V) (V) (V) (V)

Example A3-1 0.68 0.68 0.68 0.68 Example A3 -2 0.66 0.66 0.66 0.66 Example A3-3 0.67 0.67 0.67 0.67 Example A3-4 0.68 0.68 0.68 0.68 Example A3 -5 0.67 0.67 0.67 0.67 Compare Example A3-1 0.46 0.45 0.44 0.43 Comparative example A3 -2 0.66 0.66 0.65 0.64

Example A4: Fuel cell having, as an electrolyte, a layer made of SSZ on the air electrode side and a layer made of YSZ on the fuel electrode side

Example A4-1

On the air-side electrode reaction layer, a layer composed of SSZ of 90 mol% ZrO — 10 mol% ScO was formed by a slurry coating method. A YSZ layer of 90 mol% ZrO -10 mol% Y〇 was formed thereon by a slurry coating method, and then fired at 1400 ° C. The thickness of the obtained electrolyte was 30 μm (layer made of SSZ: 15 μm, layer made of YSZ: 15 / m). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A4-2

On the air-side electrode reaction layer, a layer composed of 90 mol% ZrO and 10 mol% Sc〇 SSZ was formed by a slurry coating method. A YSZ layer of 90 mol% ZrO-10 mol% Y 2 O was formed thereon by a slurry coating method, and then fired at 1350 ° C. The thickness of the obtained electrolyte was a layer composed of SOzn ^ SSZ force: 15 μπι, a layer composed of YSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A4-3

On the air-side electrode reaction layer, a layer composed of SSZ of 90 mol% ZrO -10 mol% Sc〇 was formed by a slurry coating method. A YSZ layer of 90 mol% ZrO -10 mol% Y〇 was formed thereon by a slurry coating method, and then fired at 1380 ° C. Of the resulting electrolyte The thickness was 30/1111 (332 layers: 15111, YSZ layer: 15 / im). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A4—4

On the air-side electrode reaction layer, a layer consisting of 90 mol% ZrO -10 mol% Sc〇 SSZ

2 2 3

A film was formed by a slurry coating method. On top of this, 90 mol% ZrO -10 mol% Y〇 YSZ

2 2 3

After forming a strong layer by a slurry coating method, it was baked at 1415 ° C. The thickness of the obtained electrolyte was a layer composed of SOzn ^ SSZ force: 15 x m, and a layer composed of YSZ: 15 µm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0140] Example A4_5

2 2 3

After forming a strong layer by a slurry coating method, it was sintered at 1425 ° C. The thickness of the obtained electrolyte was 30 111 (a layer composed of 332: 15/1111, a layer composed of YSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0141] Comparative example A4-1

On the air-side electrode reaction layer, a layer consisting of 90 mol% ZrO and 10 mol% Sc

2 2 3

A film was formed by a slurry coating method. On top of this, 90 mol% ZrO _ 10 mol% Y〇 YSZ

2 2 3

After forming a strong layer by the slurry coating method, it was baked at 1330 ° C. The thickness of the obtained electrolyte was 30/1 111 (a layer composed of 332: 15 111, a layer composed of YSZ: 15 / im). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0142] Comparative example A4-2

2 2 3

After forming a strong layer by the slurry coating method, it was sintered at 1440 ° C. The thickness of the obtained electrolyte was 30 × m (SSZ force, layer composed of 15 μπι, layer composed of YSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0143] The fuel cell obtained as described above was subjected to a particle size distribution, a gas leak test, a power generation test, and a durability test. The results were as shown in the following display. [Table 7]

[¾8]

Example A5: As an electrolyte, a fuel cell having a layer made of YSZ on the air electrode side and a layer made of SSZ on the fuel electrode side

Example A5-1

On the air-side electrode reaction layer, a layer composed of 90 mol% ZrO and 10 mol% Y

2 2 3

A film was formed by a slurry coating method. On top of this, 90mol% ZrO _10mol% Sc〇 SSZ

After a layer having a strength of 2 23 was formed by the slurry coating method, it was baked at 1400 ° C. The thickness of the obtained electrolyte was 30 111 (丫 32, a layer composed of 15111, a layer composed of SSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A5-2 On the air-side electrode reaction layer, a layer composed of 90 mol% ZrO and 10 mol% Y

2 2 3

After forming a layer having a high strength by a slurry coating method, it was baked at 1350 ° C. The thickness of the obtained electrolyte was 30〃111 (丫 32, a layer composed of 15〃111, a layer composed of SSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0146] Example A5_3

On the air-side electrode reaction layer, a layer consisting of a 90 mol% ZrO -10 mol% Y

2 2 3

After forming a layer having a high strength by a slurry coating method, it was baked at 1380 ° C. The thickness of the obtained electrolyte was 30〃111 (丫 32, a layer composed of 15〃111, a layer composed of SSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0147] Example A5_4

2 2 3

After forming a layer having a high strength by a slurry coating method, it was baked at 1420 ° C. The thickness of the obtained electrolyte was 30/1111 (層 32 layers: 15/1111, SSZ layer: 15 / im). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A5—5

2 2 3

After forming a layer having a high strength by a slurry coating method, it was baked at 1430 ° C. The thickness of the obtained electrolyte was 30〃111 (丫 32, a layer composed of 15〃111, a layer composed of SSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0149] Comparative Example A5-1

2 2 3

After forming a layer having a high strength by a slurry coating method, it was baked at 1330 ° C. The thickness of the obtained electrolyte was 30〃111 (丫 32, a layer composed of 15〃111, a layer composed of SSZ: 15 μm). It A fuel cell was obtained in the same manner as in Example Al-1, except for the above.

[0150] Comparative Example A5-2

On the air-side electrode reaction layer, a layer consisting of 90 mol% ZrO-10 mol% YO

2 2 3

A film was formed by a slurry coating method. On top of this, SSZ which is 90mol% ZrO _10mol% Sc O

After a layer having a strength of 2 23 was formed by the slurry coating method, it was baked at 1450 ° C. The thickness of the obtained electrolyte was 30〃111 (丫 32, a layer composed of 15〃111, a layer composed of SSZ: 15 μm). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0151] The fuel cell obtained as described above was subjected to a particle size distribution, a gas leakage test, a power generation test, and a durability test. The results were as shown in the following display.

[Table 9]

[Table 10] Initial potential After 1000 hours After 1500 hours After 2000 hours

(V) (V) (V) (V) Example A5-1 0.67 0.67 0.67 0.67 Example A5-2 0.66 0.66 0.66 0.66 Example A5-3 0.67 0.67 0.67 0.67 Example A5-4 0.67 0.67 0.67 0.67 Example A5-5 0.66 0.66 0.66 0.66 Comparative example A5-1 0.45 0.44 0.43 0.42 Comparative example A5-2 0.65 0.65 0.64 0.63 [0152] Example A6: Fuel cell in which the electrolyte has a three-layer structure

Example A6-1

On the air-side electrode reaction layer, a layer consisting of 90 mol% ZrO 10 mol% Sc〇 SSZ

2 2 3

A film was formed by a slurry coating method. On top of this, the YSZ force, which is 90 mol% ZrO _ 10 mol% Y〇,

2 2 3

This layer was formed by a slurry coating method. In addition, 90 mol% ZrO -10 mol% ScO

After a layer of SSZ was formed by a slurry coating method, it was baked at 1400 ° C. The thickness of the obtained electrolyte was 30 μm (layer composed of SSZ on the air side: 10 μm, layer composed of YSZ: 10 μm, layer composed of SSZ on the fuel electrode side: 10 μm). Was. Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0153] Example A6_2

2 2 3

This layer was formed by a slurry coating method. In addition, 90 mol% ZrO_10 mol% ScO

After a layer of SSZ was formed by the slurry coating method, it was baked at 1360 ° C. The thickness of the obtained electrolyte was 30 μm (layer composed of SSZ on the air side: 10 μm, layer composed of YSZ: 10 / im, layer composed of SSZ on the fuel electrode side: 10 / m). Was. Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A6-3

2 2 3

A film was formed by a slurry coating method. On top of this, 90 mol% ZrO _ 10 mol% Y〇

2 2 3

After a layer of SSZ was formed by the slurry coating method, it was baked at 1380 ° C. The thickness of the obtained electrolyte was 30 μm (layer composed of SSZ on the air side: 10 μm, layer composed of YSZ: 10 μm, layer composed of SSZ on the fuel electrode side: 10 μm). Was. Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

Example A6_4

2 2 3

2 2 3 This layer was formed by a slurry coating method. In addition, 90 mol% ZrO_10 mol% ScO

After a layer made of SSZ was formed by the slurry coating method, it was baked at 1420 ° C. The thickness of the obtained electrolyte was 30 μm (the layer composed of SSZ on the air side: 10 μm, the layer composed of YSZ: 10 / im, the layer composed of SSZ on the fuel electrode side: 10 μm). Was. Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0156] Example A6_5

2 2 3

After a layer of SSZ was formed by the slurry coating method, it was baked at 1440 ° C. The thickness of the obtained electrolyte was 30 μm (layer composed of SSZ on the air side: 10 μm, layer composed of YSZ: 10 μm, layer composed of SSZ on the fuel electrode side: 10 μm). Was. Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0157] Comparative Example A6-1

2 2 3

After a layer made of SSZ was formed by a slurry coating method, it was sintered at 1330 ° C. The thickness of the obtained electrolyte was 30 μm (the layer composed of SSZ on the air side: 10 μm, the layer composed of YSZ: 10 / im, the layer composed of SSZ on the fuel electrode side: 10 μΐη). Otherwise, in the same manner as in Example A1-1, a fuel cell was obtained.

[0158] Comparative Example A6-2

2 2 3

After a layer of SSZ was formed by the slurry coating method, it was sintered at 1450 ° C. The thickness of the obtained electrolyte was 30 μm (layer composed of SSZ on the air side: 10 μm, layer composed of YSZ: 10 μm, layer composed of SSZ on the fuel electrode side: 10 × m). Otherwise, as in Example A1-1 Thus, a fuel cell was obtained.

The fuel cell obtained as described above was subjected to a particle size distribution, a gas leak test, a power generation test, and a durability test. The results were as shown in the following display.

11]

[Table 12]

Example A7: Regarding thickness of electrolyte membrane

The composition of the electrolyte membrane is 90 mol% Zr〇 -5 mol% ScO -5 mol% YO, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example A1-1, except that the thickness was 8 zm.

[0161] Example A7_2 The composition of the electrolyte membrane is 90 mol% Zr〇-5 mol% ScO-5 mol% YO, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example Al-1, except that the thickness was 10 / m.

[0162] Example A7-3

The composition of the electrolyte membrane is 90 mol% Zr〇 -5 mol% Sc〇 -5 mol% YO, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example A1-1, except that the thickness was 15 zm.

[0163] Example A7-4

The composition of the electrolyte membrane is 90 mol% Zr〇 -5 mol% ScO -5 mol% Y〇, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example Al-1, except that the thickness was 30 zm.

Example A7-5

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example A1-1, except that the thickness was 50 / m.

Example A7-6

The composition of the electrolyte membrane is 90 mol% Zr〇 -5 mol% ScO— 5 mol% YO, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example Al-1, except that the thickness was 80 / m.

Example A7-7

The composition of the electrolyte membrane is 90 mol% ZrO— 5 mol% ScO— 5 mol% Y〇, 1420 ° C

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example Al-1, except that the thickness was 100 μπι.

Example A7-8

2 2 3 2 3

And a fuel cell was obtained in the same manner as in Example A1-1, except that the thickness was 120 μπι.

With respect to the fuel cell obtained as described above, a particle size distribution, a gas leak test, a power generation test , And a durability test. The results were as shown in the display below

[Table 13]

[Table 14]

Example B1

(1) Preparation of electrolyte

(1-1) Preparation of electrolyte raw material powder

An SSZ material represented by 90 mol% ZrO -10 mol% ScO was prepared as an electrolyte material.

2 2 3

It was. That is, ZrO was dissolved in concentrated nitric acid of 3N or more heated at 100 ° C, and diluted with distilled water to obtain a nitrate aqueous solution. For ScO, a nitrate aqueous solution was prepared using the same method.

twenty three Obtained. Each nitrate aqueous solution was prepared so as to have the above composition, and oxalic acid aqueous solution was added thereto for coprecipitation. The liquid obtained by co-precipitation was dried at about 200 ° C, pyrolyzed at 500 ° C, and heat-treated at 800 ° C to obtain a raw material powder. The average particle size was 0.5 / im.

[0170] (1_2) Production of pressed body

After adding 1% by weight of the binder PVA to the SSZ material and kneading and drying the powder, the powder was uniaxially molded with a disk-shaped mold and pressed to 1000 kg / cm ² to form the powder.

[0171] (1-3) Preparation of fired pressed body

The pressed body was sintered at 1430 ° C. After sintering, it was ground to a thickness of Slmm.

[0172] (1-1-4) Porosity measurement

The porosity of the fired pressed body was measured by the Archimedes method. The porosity was 0.8%, confirming that the electrolyte had no gas permeability.

[0173] (2) Preparation of mixed conductive ceramic electrode

(2-1) Preparation of raw materials

A mixed conductive ceramic material was prepared by uniformly mixing a perovskite-type oxide containing manganese and nickel and an oxide having oxygen ion conductivity. Its composition is (La

0.

SSZ (Sr) (Mn Ni) 〇 and 90mol% Zr〇 _10mol% Sc〇

75 0.25 0.98 0.95 0.05 3 2 2 3

Hereinafter, (La Sr) (Mn Ni) 〇 / 90 mol% Zr〇10 mol% Sc〇

0.75 0.25 0.98 0.95 0.05 3 2 2 3 ) And the weight ratio was 50/50. First, (La Sr) (Mn Ni) 〇

0.75 0.25 0.98 0.95 0.05 3

Was obtained as follows. The aqueous solution of each of La, Sr, Mn and Ni was mixed so as to have the above-mentioned composition, and then oxalic acid was precipitated by precipitation. The precipitate was further heat treated. After pulverizing the raw material, it was further fired at 1300 ° C. to obtain a raw material powder. Also, 90 mol% ZrO-10 mol% ScO was obtained as follows. 3N or more heated ZrO at 100 ° C

2 2 3 2

After dissolving in concentrated nitric acid and diluting with distilled water, a nitrate aqueous solution was obtained. About Sc O

twenty three

A nitrate aqueous solution was obtained in the same manner. Each nitrate aqueous solution was prepared so as to have the above-mentioned composition, and oxalic acid aqueous solution was collected and coprecipitated. The solution obtained by coprecipitation was dried at about 200 ° C, pyrolyzed at 500 ° C, and heat-treated at 1200 ° C to obtain a raw material powder. Further, each raw material was mixed and heat-treated at 1300 ° C to obtain a raw material powder. By controlling the particle size, The average particle size of the powder was 2 μm.

[2-2] Preparation of Paste

(La Sr) (Mn Ni) 0/90 mol% ZrO -10 mol% ScO = 5

0.75 0.25 0.98 0.95 0.05 3 2 2 3

10 parts by weight of ethyl cellulose as a binder and 90 parts by weight of terbineol as a solvent were added to 100 parts by weight of the raw material powder composed of 0/50, and mixed for 30 minutes to prepare a paste.

(2-3) Preparation of Electrode

The paste was applied to one surface of the electrolyte of the pressed body by a screen printing method so as to have a diameter of 6 mm, and sintered at 1400 ° C. The thickness of the electrode after firing was 20 zm. Further, a platinum electrode was applied on the electrode and the opposite side of the pressed body by a screen printing method so as to have a diameter of 6 mm, and sintered at 1100 ° C to obtain a fuel cell test piece.

[0176] Example B2

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.99 0.01 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

[0177] Example B3

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.98 0.02 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

Example B4

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.92 0.08 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

[0179] Example B5

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.90 0.10 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained. [0180] Example B6

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.87 0.13 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

[0181] Comparative example B1

Mixed conductive ceramic electrode (La Sr) MnO / 90mol% ZrO -lOmol

0.75 0.25 0.98 3 2

A fuel cell was prepared in the same manner as in Example 1 except that the mixture was prepared so that% ScO = 50Z50.

twenty three

A test piece was obtained.

[0182] Vortex pressure I constant

The test piece obtained as described above was configured as shown in FIG. 7, and the reaction overvoltage was measured. That is, an electrode 11 made of mixed conductive ceramics is formed on one surface of an electrolyte 13 made of an SSZ material, a platinum electrode 12 is formed on the surface of the electrode 11, and a counter electrode 14 made of platinum is formed on the opposite surface. A reference electrode 15 made of platinum is formed on the side surface of the electrolyte 13, and two lead wires 16 are attached to the platinum electrode 12, and one lead wire 17 and 18 are attached to the counter electrode and the reference electrode, respectively. ing. After raising the temperature of the battery to 800 ° C in the atmosphere, the overvoltage was measured by the current interruption method. Here, the current interruption method is a method of instantaneously interrupting the current flowing in the battery, and quantifying the overvoltage due to the reaction and the overvoltage due to the ohmic resistance from the voltage change at that time. In this test, the reaction overvoltage under the condition of 0.2 Acm- ² was calculated. Generally, it is said that the lower the reaction overpotential is measured, the better the electrode characteristics are.

[Table 15]

(Lao .75 Sro .25) 0.99 (Mniz iz) O3 reaction overvoltage

Z value (mV) at Example B 1 0.05 25 Example B 2 0.01 70 Example B 3 0.02 45 Example B 4 0.08 24 Example B 5 0.10 38 Example B 6 0.13 60 Comparative example B 1 0 80

[0183] As is clear from the comparison with Comparative Example B1, the reaction overvoltage is reduced by the addition of Ni. This is presumed to be because the diffusion of manganese into the electrolyte was suppressed by the inclusion of Ni. From this, it was confirmed that the diffusion of manganese was suppressed by the inclusion of Ni, and that it had good electrode characteristics. In addition, when compared with the Ni content, the reaction overpotential decreases when the Ni content exceeds 0.02, while the reaction overvoltage tends to increase when the Ni content exceeds 0.10. It can be said that Ni is more preferably in the range of 0.02-0.10.

[01841] Hereinafter, (La Sr) (Mn Ni) 0 / 90mol% ZrO -10mol% ScO = 50

0.75 0.25 y 0.95 0.05 3 2 2 3

/ 50 was tested.

Example B7

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.96 0.95 0.05 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

Example B8

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.97 0.95 0.05 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

[0187] Example B9

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.99 0.95 0.05 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3 Thus, a fuel cell test piece was obtained.

Example B 10

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% ZrO

0.75 0.25 0.95 0.05 3 2

Same as Example BIO except that it was prepared so that -10 mol% ScO = 50/50.

twenty three

Thus, a fuel cell test piece was obtained.

[0189] Example B 11

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 1.01 0.95 0.05 3

O -10 mol% Sc O Same as Example Bl except that it was prepared to be 50/50.

2 2 3

Thus, a fuel cell test piece was obtained.

[0190] Eddy voltage evaluation test

The reaction overvoltage was measured by the same overvoltage measurement method as described above. The results were as shown in the table below.

[Table 16]

[0191] When the y value is in the range of 0.97-1, the reaction overvoltage is small, but when the y value is less than 0.97 and exceeds 1.00, it rapidly increases. From the above results, it was confirmed and confirmed that a more preferable range for the y value was 0.97≤y≤l.00.

[0192] Hereinafter, the test was performed while changing the weight ratio.

Example B 12

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3 mol% ZrO-1 mol% Sc〇 = 20/80

2 2 3 Similarly, a fuel cell test piece was obtained.

[0194] Example B 13

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3 mol% ZrO -10 mol% Sc〇 = 30/70

2 2 3

Similarly, a fuel cell test piece was obtained.

[0195] Example B 14

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3 mol% ZrO -10mol% Sc〇 = 40/60

2 2 3

Similarly, a fuel cell test piece was obtained.

[0196] Example B 15

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3 mol% ZrO -10 mol% Sc〇 = 60/40

2 2 3

Similarly, a fuel cell test piece was obtained.

Example B 16

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3 mol% ZrO- 10 mol% Sc〇 = 70/30 except that it was prepared so as to be 70/30.

2 2 3

Similarly, a fuel cell test piece was obtained.

[0198] Example B 17

The weight ratio of mixed conductive ceramic electrodes is (La Sr) (Mn Ni) 0/90

0.75 0.25 0.98 0.95 0.05 3mol% ZrO — 10mol% Sc〇 = 80/20

2 2 3

Similarly, a fuel cell test piece was obtained.

[0199] Comparative Example B2

The mixed conductive ceramic electrode was adjusted to (La Sr) (Mn Ni) 0.

0.75 0.25 0.98 0.95 0.05 3

A fuel cell test piece was obtained in the same manner as in Example Bl, except that the average particle size after firing at 1300 ° C was controlled to 2 µm.

[0200] Comparative Example B3

SS with 90mol% Zr〇-10mol% ScO composition

2 2 3

Example Bl except that the average particle size after firing at 1200 ° C was controlled to 2 μm using Z material. In the same manner as described above, a fuel cell test piece was obtained.

[0201] Eddy voltage evaluation test

[Table 17]

[0202] When the weight ratio is in the range of 30 to 70% by weight, the overvoltage tends to decrease.

[0203] Hereinafter, the effects of rare earth elements other than La were tested.

[0204] Example B 18

Mixed conductive ceramic electrode (Y Sr) (Mn Ni) O / 90mol% Zr

0.75 0.25 0.98 0.95 0.05 3

A fuel cell test piece was obtained in the same manner as in Example Bl, except that the composition was adjusted so that O ₂ -10 mol% Sc ₂ O = 50/50.

Example B 19

Mixed conductive ceramic electrode (Sm Sr) (Mn Ni) O / 90mol% Z

0.75 0.25 0.98 0.95 0.05 3

A fuel cell test piece was obtained in the same manner as in Example Bl, except that r〇 ₂ -10 mol% Sc ₂ 〇 ₃ = 50/50.

[0206] Eddy voltage evaluation test

The reaction overvoltage was measured by the same overvoltage measurement method as described above. The results were as shown in the table below. [Table 18]

[0207] As a perovskite-type oxide containing at least manganese and nickel, (Ln A) (M

It was confirmed that Ln could be Sm or Y when expressed as 1—xxynNi) 〇. This power Ln

1—z z

, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. However, it was easy to estimate that the same effect could be obtained, and it was possible to confirm that it was preferable.

[0208] Hereinafter, the effect of a material having oxygen ion conductivity was tested.

[0209] Example B20

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.95 0.05 3

O-10 mol% Y O = 50/50, except that it was prepared in the same manner as in Example Bl.

2 2 3

Thus, a fuel cell test piece was obtained.

[0210] Example B21

Mixed conductive ceramic electrode (La Sr) (Mn Ni) 0 / 90mol% Zr

0.75 0.25 0.98 0.95 0.05 3

Example except that it was prepared so that 0 -5 mol% Y O -5 mol% ScO = 50/50

2 2 3 2 3

A fuel cell test piece was obtained in the same manner as in B1.

[0211] Example B22

The mixed conductive ceramic electrode is made of (La Sr) (Mn Ni) O and (CeO) (

0.75 0.25 0.98 0.95 0.05 3 2 0.8

Cerium-containing oxide represented by Sm 2 O 3 (hereinafter referred to as (La Sr) (Mn Ni

2 3 0.1 0.75 0.25 0.98 0.95 0.05

) 0 / (CeO) (Sm O). ) Was adjusted to be 50Z50 by weight.

3 2 0. 8 2 3 0. 1

Was used. (CeO) (SmO) is oxalic acid from each nitric acid solution of Ce and Sm

2 0.8 2 3 0.1

Prepared by co-precipitation method and heat-treated at 1200 ° C (La Sr) (Mn N

0.75 0.25 0.98 0.95

1) Powder mixed with 0 and fired at 1300 ° C. This electrode was sintered at 1500 ° C.

0.05 3 Except for, the procedure was the same as in Example 1.

[0212] Example B23

Mixed conductive ceramic electrodes (La Sr) (Mn Ni) 0 and 90mol% Zr

0.75 0.25 0.98 0.95 0.05 3

Cerium-containing oxide represented by O-10mol% ScO and (CeO) (Sm〇)

2 2 3 2 0.8 2 3 0.1

, (La Sr) (Mn Ni) 0 / 90mol% ZrO -10mol% Sc O / (CeO

0.75 0.25 0.98 0.95 0.05 3 2 2 3 2

) (Sm O). ) Is 50/25/25 by weight.

0.8 2 3 0 0.1

Was. (La Sr) (Mn Ni) 〇, 90 mol% ZrO -10 mol% ScO and

0.75 0.25 0.98 0.95 0.05 3 2 2 3 and (CeO 2) (Sm 2 O 3) prepared by the coprecipitation method were powder mixed, and 1300 ° C

2 0.8 2 3 0.1

A fuel cell test piece was obtained in the same manner as in Example Bl, except that it was fired.

[0213] Example B24

The mixed conductive ceramic electrode is made of (La Sr) (Mn Ni) O and La Sr G

0.75 0.25 0.98 0.95 0.05 3 0.80 0.2 a Mg lanthanum gallate-based oxide (hereinafter referred to as (La Sr) (Mn

0.8 0.8 0.2 3 0 0.75 0.25 0.98 0.9

Ni) 0 / LaSrGaMgO. ) Is 50/50 by weight

5 0.05 3 0.8 0.2 0.8 0.2 3

The prepared one was used. La Sr Ga Mg 〇 is La O, SrCO, Ga〇, Mg

0.8 0 0.2 0 0.8 0 0.2 3 2 3 3 2 3

O was blended so as to have the above composition, mixed by a ball mill, and heat-treated at 1200 ° C. Thereafter, a fuel cell test piece was obtained in the same manner as in Example B1, except that the respective powders were mixed and fired at 1300 ° C.

[0214] Comparative Example B4

Mixed conductive ceramic electrode (La Sr) MnO / 90mol% ZrO -lOmol

0.75 0.25 0.98 3 2

% Y O = 50/50 (weight ratio), except that it was prepared in the same manner as in Example Bl.

twenty three

Thus, a fuel cell test piece was obtained.

[0215] Comparative Example B5

Mixed conductive ceramic electrode (La Sr) MnO / 90mol% ZrO -5mol%

0.75 0.25 0.98 3 2

Example Bl except that it was prepared so that Sc O -5 mol% Y O = 50/50 (weight ratio)

2 3 2 3

In the same manner as described above, a fuel cell test piece was obtained.

[0216] Comparative Example B6

Mixed conductive ceramic electrode (La Sr) MnO / (CeO) (Sm〇)

0.75 0.25 0.98 3 2 0.8 2 3 0.1

= 50/50. (CeO) (SmO) is the nitric acid of each of Ce and Sm

2 0.8 2 3 0.1 The solution was prepared by coprecipitation using oxalic acid and heat-treated at 1200 ° C (La Sr

0.75 0.

) The powder was mixed with Mn〇 and baked at 1300 ° C in the same manner as in Example B22.

25 0.99 3

Thus, a fuel cell test piece was obtained.

[0217] Comparative Example B7

Mixed conductive ceramic electrode (La Sr) MnO / 90mol% ZrO -lOmol

0.75 0.25 0.98 3 2

% Sc O / (CeO) (Sm〇) = 50Z25Z25

2 3 2 0. 8 2 3 0. 1

It was. (La Sr) Mn〇, 90 mol% ZrO _10 mol% ScO and (Ce〇) (

0.75 0.25 0.98 3 2 2 3 2 0.8

Sm O) prepared by the coprecipitation method were powder mixed and fired at 1300 ° C

2 3 0.1

Except for the above, a fuel cell test piece was obtained in the same manner as in Example B1.

[0218] Comparative Example B8

(La Sr) MnO / La Sr Ga Mg

0.75 0.25 0.98 3 0.8 0.8 0.2 0.8 0.8

Those prepared so that O = 50/50 were used. La Sr Ga Mg O

3 0.8 0.8 0.2 0.8 0.2 3 2

O, SrCO, Ga〇, MgO are blended so as to have the above-mentioned composition, and after mixing with a ball mill, 1

3 3 2 3

Heat treated at 200 ° C. Thereafter, a fuel cell test piece was obtained in the same manner as in Example B1, except that the respective powders were mixed and fired at 1300 ° C.

[0219] Eddy voltage evaluation test

[Table 19]

[0220] Forces using YSZ, ScYSZ, cerium-containing oxides, mixed materials of SSZ and cerium oxide, and lanthanum gallate-based oxides as materials having oxygen ion conductivity. Perovskite containing at least manganese and nickel When mixed with oxides, the reaction overvoltage was low, but when nickel was not included, the reaction overvoltage was large, and nickel was added to perovskite-type oxides containing manganese. It was confirmed that the characteristics were significantly improved. In each case, it is inferred that the diffusion of manganese into the electrolyte was suppressed and the electrode characteristics were improved.

[0221] eyes

Example B25

(1) Preparation of cathode support

0.75 0.25 3

And After preparation by the coprecipitation method, heat treatment was performed to obtain air electrode raw material powder. The average particle size was 30 zm. A cylindrical molded body was produced by an extrusion molding method, and was baked at 1500 ° C to obtain an air electrode support. The pore diameter of the cathode support is 14 zm, the porosity is 45%, The thickness was 1.5 mm.

[0222] (2) Preparation of air-side electrode reaction layer

The air-side electrode reaction layer is a layer in which a perovskite-type oxide containing manganese and nickel and YSZ are uniformly mixed, and the composition and its weight ratio are (La Sr) (Mn

0.75 0.25 0.95

Ni) 0 / 90mol% ZrO_10mol% Y〇 = 50/50

0.05 3 2 2 3

. Using the respective nitrate aqueous solutions of La, Sr, Mn, Ni, Zr and Y, they were prepared to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 xm. 40 parts by weight of this powder were mixed with 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate). After mixing, the slurry was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. The slurry was formed on the surface of the above-prepared air electrode support (outside diameter: 15 mm, wall thickness: 1.5 mm, effective length: 400 mm) by a slurry coating method, and then sintered at 1400 ° C. The pore size of the formed layer was 5 _βm , the porosity was 28%, and the thickness was 30 μm.

(3) Preparation of Electrolyte Slurry:

The material of the electrolyte was YSZ, and its composition was 90 mol% ZrO_10 mol% YO. Zr

2 2 3,

Y was prepared by using each nitrate aqueous solution to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 μm. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. This slurry had a viscosity of 140 mPas.

[0224] (4) Preparation of electrolyte

The prepared slurry was formed into a film by the slurry coating method on the surface of the air-side electrode reaction layer prepared in (2) above, and sintered at 1400 ° C. The thickness of the obtained electrolyte was 30 x m. The portion where the interconnector was to be formed in a later step was masked, and the film was not coated so as to be removed.

(5) Slurry preparation of fuel-side electrode reaction layer The material of the fuel-side electrode reaction layer is Ni〇 / SSZ, and its composition is NiO / (ZrO) (Sc

2 0. 90 2

O). Using the nitrate aqueous solution of each of Ni, Zr and Sc,

3 0. 10

After that, oxalic acid was added for precipitation. After the precipitate and the supernatant were dried, they were further subjected to a heat treatment to control the particle size to obtain a raw material. Two types of the fuel-side electrode reaction layer were produced, with the weight ratio of NiO / (ZrO) (ScO) = 20Z80 and 50/50. Average grain

2 0.90 2 3 0.10

The diameters were all 0. 100 parts by weight of this powder and an organic solvent (ethanol) 5

00 parts by weight, binder (ethyl cellulose) 10 parts by weight, dispersant (polyoxyethylene alkyl phosphate ester) 5 parts by weight, defoamer (sorbitan sesquiolate) 1 part by weight, and plasticizer (DBP) 5 After mixing the parts by weight, the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 70 mPas.

(6) Preparation of Fuel-Side Electrode Reaction Layer

The electrolyte layer prepared in (4) above is masked so that the effective area becomes 150 cm ² , and the slurry NiO / (ZrO) prepared in (5) is coated on the electrolyte layer by a slurry coating method.

2 0.

(Sc O) = 20/80 (average particle diameter 0.55 η), and 50/50 (average particle diameter 0

90 2 3 0.10

5 / m). The film thickness (after sintering) was 10 μm.

(7) Slurry preparation of fuel electrode:

The fuel electrode material was NiO / YSZ and the composition was NiO / (ZrO) (Y ().

2 0.90 2 3 0.10

. Using the respective nitrate aqueous solutions of Ni, Zr and Y, the mixture was prepared to have the above-mentioned composition, and oxalic acid was precipitated. After the precipitate and the supernatant were dried, they were further subjected to a heat treatment to control the particle size and obtain a raw material. Its composition and its weight ratio is NiO / (ZrO) (

2 0. 90

YΟ) = 70/30, and the average particle size was 2 im. 100 parts by weight of this powder

2 3 0. 10

500 parts by weight of solvent (ethanol), 20 parts by weight of binder (ethyl cellulose), 5 parts by weight of dispersant (polyoxyethylene alkyl phosphate), 1 part by weight of defoamer (sorbitan sesocholate), and plastic After mixing 5 parts by weight of the agent (DBP), the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 250 mPas.

[0228] (8) Preparation of fuel electrode

The slurry prepared in (7) was formed on the fuel-side electrode reaction layer prepared in (6) by a slurry coating method. The film thickness (after sintering) was 90 xm. In addition, the fuel-side electrode reaction The layer and anode were co-sintered at 1400 ° C.

(9) Fabrication of interconnector:

Composition of lanthanum chromite in which Ca represented by composition La Ca CrO is dissolved

0.70 0.30 3

Kuta was made. Powder was prepared by spray pyrolysis and then heat-treated. The average particle size of the obtained powder was 1 μm. 40 parts by weight of this powder are 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) 1 After that, the mixture was mixed well with the mixture and stirred sufficiently to prepare a slurry. The slurry viscosity was 100 mPas. An interconnector was formed by a slurry coating method and sintered at 1400 ° C. The thickness after sintering was 40 x m.

[0230] Comparative Example B9

As the air-side electrode reaction layer, the composition and weight ratio are La Sr MnO / 90mol% ZrO_1

0.75 0.25 3 2

It was assumed that 0 mol% Y O = 50/50. La, Sr, Mn, Zr and Y each nitric acid

twenty three

Using a salt aqueous solution, the mixture was prepared so as to have the above composition, and then coprecipitation with oxalic acid was performed.

. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 μΐη. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethylcellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (sorbitan sesquis) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. The slurry was formed into a film on the surface of the air electrode support by a slurry coating method and then sintered at 1400 ° C. The thickness was 30 μm. A fuel cell was obtained in the same manner as Example B25 except for the above.

[0231] The fuel cell obtained as described above was subjected to the Mn content, gas leak test, power generation test, and durability test on the surface of the electrolyte on the fuel electrode side. The results were as shown in the display below.

[Table 20] Gas permeation amount M n amount Initial potential

(xlO! Oms! Pa ¹ ) (wt%) (V) Example B 25 6.5 2.9 0.57 Comparative example B 9 6.5 5.5 0.48

[Table 21]

[0232] Table 7 shows the estimated potential after 40,000 hours, because the lifetime required for a stationary fuel cell is 40,000 hours. In general, it is considered that there is no problem if the potential decrease rate after 40,000 hours is 10% or less.

[0233] Hereinafter, the thickness of the air-side electrode reaction layer was tested.

[0234] Example B26

A fuel cell was obtained in the same manner as in Example 25 except that the thickness of the air-side electrode reaction layer was 3 μm.

Example B27

Except that the thickness of the air-side electrode reaction layer and 5 _beta m in the same manner as in Example Beta25, a fuel cell was obtained.

[0236] Example B28

A fuel cell was obtained in the same manner as in Example 25 except that the thickness of the air-side electrode reaction layer was set to 20 _βm .

[0237] Example B29

The thickness of the air-side electrode reaction layers except that the 50 _beta m in the same manner as in Example Beta25, to obtain a fuel cell.

[0238] Example B30 A fuel cell was obtained in the same manner as in Example 25 except that the thickness of the air-side electrode reaction layer was 55 μm.

[0239] The fuel cell obtained as described above was subjected to the same gas leak test, power generation test, durability test, and composition analysis of the electrolyte surface as described above. The results were as shown below.

[Table 22]

[Table 23]

[0240] From the above, it can be seen that the thickness of the air-side electrode reaction layer is more preferably in the range of 5-50 / m from the viewpoint of output performance and durability performance.

[0241] Effect of double layer of air-side electrode reaction layer

Example B31

The material of the second air-side electrode reaction layer is SSZ, and its composition is 90 mol% ZrO -lOmol

2

% Sc O. Using the aqueous nitrate solutions of Zr and Sc, adjust to the above composition.

twenty three

After combining, coprecipitation with oxalic acid was performed. Raw material powder that has been subjected to heat treatment to control the particle size I got the end. The average particle size was 2 μΐη. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (sorbitan sesquiolate) After mixing 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed into a film by slurry coating on the surface of the air-side electrode reaction layer obtained in Example B25 (2), and then sintered at 1400 ° C. The pore size of the second layer was 1.5 zm, the porosity was 14%, and the thickness was 10 zm. A fuel cell was obtained in the same manner as Example B25 except for the above.

[0242] Example B32

A fuel cell was obtained in the same manner as in Example B31, except that the thickness of the second air-side electrode reaction layer was changed to 3 μm.

[0243] Example B33

A fuel cell was obtained in the same manner as in Example B31, except that the thickness of the second air-side electrode reaction layer was set to 5 μm.

Example B34

A fuel cell was obtained in the same manner as in Example B31, except that the thickness of the second air-side electrode reaction layer was set to 30 μm.

Example B35

A fuel cell was obtained in the same manner as in Example B31, except that the thickness of the second air-side electrode reaction layer was set to 50 μm.

[0246] Example B36

A fuel cell was obtained in the same manner as in Example B31, except that the thickness of the second air-side electrode reaction layer was set to 55 μm.

[0247] The fuel cell obtained as described above was subjected to the same gas leak test, power generation test, durability test, and composition analysis of the electrolyte surface as described above. In the composition analysis, in addition to the surface of the electrolyte in contact with the fuel electrode, the manganese content on the surface of the electrolyte in contact with the second air-side electrode reaction layer was similarly measured. The measurement was also performed for Comparative Example B9 in the same manner. The results were as shown below. [Table 24]

[Table 25]

[0248] It can be seen that it is more preferable to provide the second air-side electrode reaction layer, and it is more preferable that the thickness is in the range of 5-50 µΐη.

[0249] Hereinafter, the configuration of the electrolyte was tested.

[0250] Example B37

The material of the electrolyte is ScYSZ, and its composition is 90 mol% ZrO_5 mol% ScO-5 mol%

2 2 3

Y O. Using each nitrate aqueous solution of Zr Y Sc, adjust to the above composition.

twenty three

After combining, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. A fuel cell was obtained in the same manner as Example B25 except for the above. [0251] Example B38

The material of the electrolyte was SSZ, and its composition was 90 mol% Zr〇_10 mol% ScO. Zr

2 2 3,

After each Sc was mixed to have the above-mentioned composition using each nitrate aqueous solution, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. A fuel cell was obtained in the same manner as Example B25 except for the above.

[0252] Example B39

The material of the electrolyte is SSZ with a composition of 90 mol% ZrO -10 mol% Sc〇, and a composition of 90 mol%

2 2 3

YSZ of l% ZrO-10mol% YO was used. YSZ slurry on the surface of the air-side electrode reaction layer

2 2 3

After the film was formed by one coat method, SSZ was formed on the YSZ surface by the slurry coat method and sintered at 1400 ° C. The thickness of each layer was 15 x m. A fuel cell was obtained in the same manner as Example B25 except for the above.

[0253] Example B40

The material of the electrolyte was SSZ with a composition of 90 mol% ZrO_10 mol% ScS, and a composition of 90 mol%

2 2 3

YSZ of l% ZrO-10mol% YO was used. Slurry SSZ on the surface of the air-side electrode reaction layer

2 2 3

After forming the film by one coating method, YSZ was formed on the SSZ surface by the slurry coating method, and further, SSZ was formed on the YSZ surface by the slurry coating method. Each layer was co-sintered at 1400 ° C. The thickness of each layer was 10 μm. Except for the above, the procedure was the same as that of Example B25.

[0254] The fuel cell obtained as described above was subjected to the same gas leak test, power generation test, durability test, and composition analysis of the electrolyte surface as described above. The results were as shown below.

[Table 26]

[Table 27] 40000 hours

¾7tB lightning <f r after 1000 between 1500 hours after 2000 hours

Estimated potential after (V) (V) (V) (V)

(V) Example B 25 0.57 0.57 0.57 0.57 0.54 Example B 37 0.60 0.60 0.60 0.60 0.57 Example B 38 0.61 0.61 0.61 0.61 0.58 Example B 39 0.61 0.61 0.61 0.61 0.58 Example B 40 0.62 0.62 0.62 0.62 0.59

[0255] Example CI

(1) Preparation of cathode support

0.75 0.25 3

It was. After preparation by the coprecipitation method, heat treatment was performed to obtain air electrode raw material powder. The average particle size was 30 / m. A cylindrical molded body was produced by an extrusion molding method. Furthermore, sintering was performed at 1500 ° C to obtain an air electrode support. The pore diameter of the air electrode support was 14 / m, the porosity was 45%, and the wall thickness was 1.5 mm.

[0256] (2) Preparation of air-side electrode reaction layer (first layer)

The first layer is a layer in which (La A) MnO and YSZ are uniformly mixed, and its composition and

13

The weight ratio is La Sr MnO / 90mol% ZrO— 10mol% Y〇 = 50/50

0.75 0.25 3 2 2 3

Was prepared and used. The aqueous solution of each of La, Sr, Mn, Zr and Y was mixed to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 zm. 40 parts by weight of the powder of the first layer were mixed with 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (sorbitan). (Sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. The slurry was formed on a surface of an air electrode support (outside diameter: 15 mm, wall thickness: 1.5 mm, effective length: 400 mm) by a slurry coating method, and then sintered at 1400 ° C. The pore size of the first layer was 5 μΐη, the porosity was 28%, and the thickness was 20 μΐη. [0257] (3) Preparation of air-side electrode reaction layer (second layer)

The material of the second layer was SSZ, and the composition was 90 mol% ZrO-10 mol% ScO. Z

The respective compositions were prepared using the respective aqueous nitrate solutions of 230 r and Sc so as to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 μm. 40 parts by weight of this powder are mixed with 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate ester), and an antifoaming agent (sorbitan sesquiolate). After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was sintered at 1400 ° C. after forming a film on the surface of the first layer by a slurry coating method. The pore size of the second layer was 1.5 μm, the porosity was 14%, and the thickness was 10 μm.

( ⁴ ) Preparation of Slurry of Electrolyte:

The material of the electrolyte was YSZ, and the composition was 90 mol% ZrO-10 mol% YO. Zr

2 2 3,

Y was prepared by using each nitrate aqueous solution to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 μm. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 140 mPas.

[0259] (5) Preparation of electrolyte

The prepared slurry was formed on the second layer by a slurry coating method, and sintered at 1400 ° C. The thickness of the obtained electrolyte was 30 / im. In the post-process, the portion where the interconnector was to be formed was subjected to masking, so that the film was not applied.

[0260] (6) Preparation of slurry for fuel-side electrode reaction layer

The material of the fuel-side electrode reaction layer is Ni〇 / SSZ, and its composition is Ni〇 / (ZrO) (Sc

2 0. 90 2

O). Using the nitrate aqueous solution of each of Ni, Zr and Sc,

3 0. 10

After that, oxalic acid was added for precipitation. After drying the precipitate and the supernatant, it was further subjected to a heat treatment to control the particle size to obtain a raw material. The weight ratio of the fuel-side electrode reaction layer was NiO / (ZrO) (ScO) = 20/80 and 50Z50.

2 0.90 2 3 0.10 Was 0.5 μΐη. 100 parts by weight of this powder, 500 parts by weight of an organic solvent (ethanol), 10 parts by weight of a binder (ethyl cellulose), 5 parts by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesozoate) Rate) and 5 parts by weight of a plasticizer (DBP), and then sufficiently stirred to prepare a slurry. The viscosity of this slurry was 70 mPas.

(7) Preparation of Fuel-Side Electrode Reaction Layer

The electrolyte layer prepared in (5) above is masked so that the effective area becomes 150 cm ² , and Ni〇 / (Zr〇) (Sc O) (average particle diameter) is applied onto the electrolyte layer by a slurry coating method.

2 0.90 2 3 0.10

Films were formed in the order of 20/80 (0.5 μm) and 50/50 (0.5 μm). The film thickness (after sintering) was 10 μm.

(8) Preparation of slurry for fuel electrode:

The fuel electrode material was Ni〇 / YSZ and its composition was Ni〇 / (Zr〇) (Y O).

2 0.90 2 3 0.10

. After using the respective nitrate aqueous solutions of Ni, Zr and Y to prepare the above composition, oxalic acid was precipitated. After the precipitate and the supernatant were dried, they were further subjected to a heat treatment to control the particle size and obtain a raw material. The composition and its weight ratio is Ni〇 / (Zr〇) (Y O

2 0. 90 2

) = 70/30 and the average particle size was 2 / m. 100 parts by weight of this powder and organic solvent

3 0. 10

500 parts by weight of medium (ethanol), 20 parts by weight of binder (ethyl cellulose), 5 parts by weight of dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of defoamer (sorbitan seso cholate), plasticizer After mixing 5 parts by weight of (DBP), the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 250 mPas.

[0263] (9) Preparation of fuel electrode

A fuel electrode slurry was formed on the fuel-side electrode reaction layer by a slurry coating method. The film thickness (after sintering) was 90 x m. Furthermore, the fuel electrode reaction layer and the fuel electrode were co-sintered at 1400 ° C.

(10) Fabrication of interconnector:

The composition of lanthanum chromite with a solid solution of Ca, whose composition is represented by La Ca CrO

0.70 0.30 3

Nectar was prepared. After being produced by the spray pyrolysis method, it was obtained by performing a heat treatment. The average particle size of the obtained powder was 1 μm. 40 parts by weight of this powder are mixed with 100 parts by weight of solvent (ethanol) Parts, a binder (ethyl cellulose) 2 parts by weight, a dispersant (polyoxyethylene alkyl phosphate) 1 part by weight, and an antifoaming agent (sorbitan sesquiolate) 1 part by weight, and then sufficiently stirred. To prepare a slurry. The slurry viscosity was 100 mPas. An interconnector was formed by a slurry coating method and sintered at 1400 ° C. The thickness after sintering was 40 xm.

[0265] Comparative Example C1

The material of the air-side electrode reaction layer was YSZ, and its composition and weight ratio were 90 mol% ZrO-10 mol% YO. Using the respective nitrate aqueous solutions of Zr and Y,

2 2 3

After that, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 × m. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate ester), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed into a film on the surface of the air electrode support by a slurry coating method, and then sintered at 1400 ° C. The thickness was 30 / im. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0266] Comparative Example C2

The air-side electrode reaction layer is a layer in which (La A) MnO and YSZ are uniformly mixed,

13

And its weight ratio is La Sr MnO / 90mol% ZrO -10mol% Y O = 50 /

0.75 0.25 3 2 2 3

What was 50 was prepared and used. Using the aqueous solutions of the respective nitrates of La, Sr, Mn, Zr, and Y, the mixture was prepared to have the above-mentioned composition, and then coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 zm. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (Sorbitan sesquio) Rate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed into a film on the surface of the cathode support by a slurry coating method, and then sintered at 1400 ° C. The thickness was 30 xm. A fuel cell was obtained in the same manner as Example C1, except for the above. [0267] Comparative Example C3

The air-side electrode reaction layer is represented by (La A) MnO and the general formula (Ce〇) (Y Ο)

1— 3 2 0. 8 2 3 0. 1

A layer in which a cerium-containing oxide is uniformly mixed (hereinafter referred to as (La A) MnO / (CeO) (

1— x x y 3 2 0.8

Y〇). ) And its composition and its weight ratio are La Sr MnO / (Ce

2 3 0.1 0.75 0.25 3

〇) Those with (Y〇) = 50/50 were prepared and used. About La Sr MnO

20.8 2 3 0.10.15 0.25 3 After using La, Sr and Mn nitrate aqueous solutions to prepare the above composition, coprecipitation with oxalic acid was performed. Was. Further, heat treatment was performed at 1200 ° C. (CeO)

2 0

For (Y O), use the aqueous nitrate solutions of Ce and Y to achieve the above composition.

. 8 2 3 0. 1

After that, coprecipitation with oxalic acid was performed. Further, heat treatment was performed at 1200 ° C. La Sr Mn〇 powder and (Ce〇) (Y Ο) powder heat treated at 1200 ° C

After mixing 0.75 0.25 3 2 0.82 30.1 by the powder mixing method, the mixture was heat-treated at 1400 ° C., and the particle size was controlled to obtain a raw material powder. The average particle size was 5 x m. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. The slurry was formed into a film on the surface of the cathode support by a slurry coating method and then sintered at 1400 ° C. The thickness was 30 μΐη. A fuel cell was obtained in the same manner as Example C1 except for the above.

[0268] Comparative Example C4

A fuel cell was obtained in the same manner as in Comparative Example C3, except that the electrolyte was sintered at 1500 ° C.

[0269] The fuel cell obtained as described above was subjected to the Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 28] Toru Sword: id Mn amount Initial potential

(xlO ^ ms! Pa ¹ ) (wt%) (V)

Example C 1 1.8 2.8 0.61

Comparative Example C 1 3.0 4.8 0.40

Comparative Example C 2 6.5 5.5 0.48

Comparative Example C 3 210 0.1 0.41

Comparative Example C4 17.5 4.8 0.54

[Table 29]

[0270] Hereinafter, the pore size of the second layer of the air-side electrode reaction layer was tested.

[0271] Example C2

The average particle diameter of the raw material of the second layer was set to 0, and the film was formed on the surface of the first layer by the slurry coating method, and then sintered at 1350 ° C. A fuel cell was obtained.

[0272] Example C3

The average particle diameter of the raw material of the second layer was set to 0.5 μπι, and a film was formed on the surface of the first layer by a slurry coating method, and then sintered at 1380 ° C in the same manner as in Example C1. A fuel cell was obtained.

[0273] Example C4

The average particle size of the raw material of the second layer is set to 0.5 μπι, and the slurry coating method Then, a fuel cell was obtained in the same manner as in Example C1, except that sintering was performed at 1400 ° C.

[0274] Example C5

In the same manner as in Example C1, except that the average particle diameter of the raw material of the second layer was set to 2 μm, a film was formed on the surface of the first layer by a slurry coating method, and then sintered at 1430 ° C. Thus, a fuel cell was obtained.

[0275] Example C6

In the same manner as in Example C1, except that the average particle diameter of the raw material of the second layer was set to 5 μm, and a film was formed on the surface of the first layer by a slurry coating method, and then sintered at 1430 ° C. Thus, a fuel cell was obtained.

[0276] Example C7

In the same manner as in Example C1, except that the average particle diameter of the raw material of the second layer was set to 5 μm, a film was formed on the surface of the first layer by a slurry coating method, and then sintered at 1450 ° C. Thus, a fuel cell was obtained.

[0277] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 30] Pore size Porosity Gas permeation amount M n amount Initial potential

(%) (x lO! Oms! Pa- ¹ ) (wt%) (V) Example C 1 2 14 1.8 2.8 0.61 Example C 2 0.2 6 1.5 2.3 0.61 Example C 3 0.1 3 1.1 4.0 0.60 Example C 4 0.08 2 0.6 4.6 0.55 Example C 5 5 25 3.2 3.5 0.60 Example C 6 10 40 8.5 3.2 0.60 Example C 7 12 43 14.5 4.4 0.55 [Table 31]

[0278] In Example 5-7 to compare the gas permeability of the electrolyte layer preferably Q≤2.8X10- ⁹ ms- ^ a- In ¹ preferred than a force Q≤2.8X10- ¹ ^<3 ms- ^ a- 1 Not in the range. On the other hand, in Example C14, more preferable Q≤2.8X10— “s—Pa— ¹ . Considering the gas permeability of the electrolyte, the pore diameter dl of the air electrode and the pore diameter d2 of the first layer are considered. It can be seen that the pore diameter d3 of the second layer is preferably dl>d2> d3.

Further, it can be seen that the porosity of the second layer is more preferably 3-40%.

[0279] Hereinafter, the thickness of the second layer of the air-side electrode reaction layer was tested.

[0280] Example C8

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the second layer was 3 μm. [0281] Example C9

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the second layer was set to 5 μm.

[0282] Example C 10

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the second layer was 30 xm.

Example C 11 A fuel cell was obtained in the same manner as in Example CI, except that the thickness of the second layer was set to 50 μΐη.

Example C 12

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the second layer was 55 μm.

[0285] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 32]

[Table 33]

40000 hours After initial potential After 1000 hours After 1500 hours After 2000 hours

(V) (V) (V) (V) Estimated potential

(V) Example C 1 0.61 0.61 0.61 0.61 0.58 Example C 8 0.55 0.55 0.55 0.55 0.51 Example C 9 0.59 0.59 0.59 0.59 0.56 Example C 10 0.62 0.62 0.62 0.62 0.59 Example C 11 0.60 0.60 0.60 0.60 0.57 Example C12 0.55 0.55 0.55 0.55 0.52 [0286] From the above, it is understood that the thickness of the second layer is more preferable than the force in the range of 5-50 / im.

It can be seen that the manganese component content on the fuel electrode side surface of the electrolyte is more preferably 0.3-4% by weight.

[0287] Hereinafter, the thickness of the first layer of the air-side electrode reaction layer was tested.

Example C 13

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the first layer was 3 μm.

Example C 14

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the first layer was 5 μm.

[0290] Example C 15

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the first layer was 30 μm.

[0291] Example C 16

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the first layer was changed to 50 μm.

[0292] Example C 17

A fuel cell was obtained in the same manner as in Example C1, except that the thickness of the first layer was 55 μm.

[0293] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

34] Thickness Gas permeation amount M n amount Initial potential (^ m) (xlO! Oms! Pa ¹ ) (wt%) (V) Example C 1 20 1.8 2.8 0.61 Example C 13 3 4.0 4.5 0.55 Example C 14 5 2.5 4.0 0.58 Example C 15 30 1.5 2.7 0.61 Example C 16 50 2.8 2.5 0.59 Example C 17 55 4.0 2.4 0.55 [Table 35]

[0294] From the above, it is understood that the thickness of the first layer is more preferably in the range of 5-50 / im.

[0295] Hereinafter, tests were performed by changing the materials in the first layer and the second layer of the air-side electrode reaction layer.

[0296] Example C 18

The material of the second layer is ScYSZ, and the composition is 90 mol% ZrO— 5 mol% Sc〇— 5 mol% Y

2 2 3

O was set. Using the respective nitrate aqueous solutions of Zr, Sc and Y,

twenty three

After the preparation, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 μπι. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

Example C 19

The first layer is a layer in which (La A) MnO and SSZ are uniformly mixed, and the composition and

-x 3

The weight ratio is La Sr MnO / 90mol% ZrO -10mol% Sc O = 50/50

0.75 0.25 3 2 2 3 was prepared and used. Using the respective nitrate aqueous solutions of La, Sr, Mn, Zr, and Sc, they were prepared to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 m. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0298] Example C20 The first layer is a layer in which (La A) (Mn Ni) O and SSZ are uniformly mixed, and its composition

1— 1— ό

And its weight ratio is (La Sr) (Mn Ni) 〇 / 90mol% ZrO 1 lOmol

0.75 0.25 0.95 0.05 3 2

% Sc O = 50/50 was prepared and used. La, Sr, Mn, Ni, Zr, and Sc

twenty three

Were prepared to have the above-mentioned composition using the respective nitrate aqueous solutions, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 μm. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0299] Example C21

The first layer is a layer in which (La A) (Mn Ni) O and ScYSZ are uniformly mixed.

1— 1— 3

The composition and its weight ratio are (La Sr) (Mn Ni) 〇 / 90mol% ZrO-5

0.75 0.25 0.95 0.055 2 mol% Sc〇 -5 mol% Y〇 = 50/50 was prepared and used. La, Sr, Mn,

2 3 2 3

Using the nitrate aqueous solution of each of Ni, Zr, Y, and Sc, they were prepared to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 μΐη. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0300] The fuel cell obtained as described above was subjected to the Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 36]

[Table 37] 40000 hours After initial lightning 1000 hours 1500 hours 2000 hours

(V) (V) (V) (V) Estimated potential

(V) Example C 1 0.61 0.61 0.61 0.61 0.58 Example C18 0.59 0.59 0.59 0.59 0.56 Example C19 0.64 0.64 0.64 0.64 0.61 Example C20 0.69 0.69 0.69 0.69 0.66 Example C21 0.68 0.68 0.68 0.68 0.65

[0301] Composition of electrolyte

2 2 3

Y O. Using the aqueous nitrate solutions of Zr, Y, and Sc, adjust to the above composition.

twenty three

After combining, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 / m. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0302] Example C23

The material of the electrolyte was SSZ, and its composition was 90 mol% Zr〇_10 mol% ScO. Zr,

2 2 3

After each Sc was mixed to have the above-mentioned composition using each nitrate aqueous solution, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0303] Example C24

The material of the electrolyte is SSZ and YSZ, and its composition is 90 mol% Zr〇 -10 mol% ScO

22 and 90 mol% ZrO-10 mol% YO. YSZ slurry on the surface of the second layer

3 2 2 3

After forming the film by the coating method, SSZ was formed on the YSZ surface by the slurry coating method. Sintered at 1400 ° C. The thickness of each layer was 15 × m. A fuel cell was obtained in the same manner as Example C1, except for the above.

[0304] Example C25

The electrolyte material is SSZ and YSZ, and its composition is 90 mol% Zr〇 _10 mol% ScO

twenty two And 90 mol% ZrO -10 mol% YO. Slurry SSZ on the second layer surface

3 2 2 3

After forming the film by the coating method, YSZ was formed on the SSZ surface by the slurry coating method, and then SSZ was formed on the YSZ surface by the slurry coating method. Each layer was co-sintered at 1400 ° C. The thickness of each layer was 10 zm. Except for the above, a fuel cell was obtained in the same manner as in Example C1.

[0305] The fuel cell obtained as described above was subjected to the Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 38]

[Table 39]

Example D1

(1) Preparation of cathode support For the air electrode, a solid solution of Sr prepared to be La Sr MnO composition

0.75 0.25

: Air electrode raw material powder was obtained by heat treatment after production by a coprecipitation method. The average particle size was 30 μΐη. A cylindrical molded body was produced by an extrusion molding method. Further, firing was performed at 1500 ° C. to obtain an air electrode support. The pore size was 14 zm, the porosity was 45%, and the wall thickness was 1.5 mm.

(2) Preparation of air-side electrode reaction layer

13

La Sr MnO / 90mol% Zr〇—10mol% Y〇 = 50/5

0.75 0.25 3 2 2 3

What was 0 was prepared and used. Using the aqueous nitrate solutions of La, Sr, Mn, Zr, and Y, the mixture was prepared to have the above-mentioned composition, and coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 zm. 40 parts by weight of this powder are 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed into a film on the surface of the cathode support by a slurry coating method and then sintered at 1400 ° C. The thickness was 30 μm.

(3) Preparation of Electrolyte Slurry:

The material of the electrolyte is YSZ, and the composition is 90 mol% ZrO-10 mol% YO.

2 2 3

Prepared and used. Using the respective nitrate aqueous solutions of Zr and Y, the mixture was adjusted to have the above composition, and then coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 / m. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing with parts by weight, the slurry was sufficiently stirred to prepare a slurry. The slurry viscosity was 140 mPas.

(4) Preparation of electrolyte

The prepared slurry was formed into a film on the surface of the air-side electrode reaction layer by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained electrolyte was 30 xm. It should be noted that, in the subsequent step, the portion where the interconnector is to be formed is masked and the film is not applied. I did it. The porosity was 1%.

(5) Slurry preparation of porous layer composed of fluorite-type oxide containing dinoreconia

The material of the porous layer made of fluorite-type oxide containing dinoreconia was SSZ, and the composition was 90 mol% ZrO-10 mol% ScS. Zr

Each of the aqueous solutions of 22 3 and Sc was mixed so as to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 5 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing with the mixture, the mixture was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 200 mPas.

[0311] (6) Preparation of porous layer composed of fluorite-type oxide containing dinoreconia

The prepared slurry was formed into a film on the surface of the electrolyte layer by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 μΐη. The portion where the interconnector film is formed in a later step is masked so that the film is not applied. The porosity was 15% and the pore size was 0.3 μΐη.

[0312] (7) Preparation of slurry for fuel-side electrode reaction layer

The material of the fuel-side electrode reaction layer is Ni〇 / SSZ, and its composition is NiO / (ZrO) (Sc

2 0. 90 2

O). Using the nitrate aqueous solution of each of Ni, Zr and Sc,

3 0. 10

After that, oxalic acid was added for precipitation. After drying the precipitate and the supernatant, the mixture was further subjected to a heat treatment to control the particle size to obtain a raw material. Two types of the fuel-side electrode reaction layer were manufactured, in which the weight ratio of NiO / (ZrO) (ScO) = 20/80 and 50/50. Average particle size

2 0.90 2 3 0.10

Was 0. 100 parts by weight of this powder, 500 parts by weight of an organic solvent (ethanol), 10 parts by weight of a binder (ethyl cellulose), 5 parts by weight of a dispersant (polyoxyethylene alkynoleic acid ester), and an antifoaming agent (sorbitan sesozoate) Rate) and 5 parts by weight of a plasticizer (DBP), and then sufficiently stirred to prepare a slurry. The viscosity of this slurry was 70 mPas.

[0313] (8) Preparation of fuel-side electrode reaction layer

Mask the porous layer prepared in (6) above so that the effective area is 150 cm ² , Ni〇 / (Zr〇) (Sc O) (average particle size) = on the porous layer by slurry coating method

2 0.90 2 3 0.10

Films were formed in the order of 20/80 (0.5 μm) and 50/50 (0.5 / im). The film thickness (after sintering) was 10 / im.

(9) Slurry preparation of fuel electrode:

2 0.90 2 3 0.10

2 0. 90 2

) = 70/30, and the average particle size was 2 μm. 100 parts by weight of this powder and organic solvent

3 0. 10

₅₀₀ parts by weight of a medium (ethanol), 20 parts by weight of a binder (ethyl cellulose), ₅ parts by weight of a dispersant (polyoxyethylene alkyl phosphate), 1 part by weight of an antifoaming agent (sorbitan sesquioleate), After mixing with 5 parts by weight of a plasticizer (DBP), the slurry was sufficiently stirred to prepare a slurry. The viscosity of this slurry was 250 mPas.

[0315] (10) Preparation of fuel electrode

A fuel electrode slurry was formed on the fuel-side electrode reaction layer by a slurry coating method. The film thickness (after sintering) was 90 μΐη. Further, the fuel electrode reaction layer and the fuel electrode were co-sintered at 1400 ° C.

[0316] (11) Preparation of interconnectors

0.70 0.30 3

Kuta 1 was made. The raw material powder was prepared by a spray pyrolysis method and then heat-treated. The average particle size of the obtained powder was 1 μΐη. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. An interconnector was formed by a slurry coating method and sintered at 1400 ° C. The thickness after sintering was 40 μm.

The thickness shown here was obtained by cutting the cell, observing the cross section from the air electrode to the fuel electrode by SEM, and calculating from the scale of the photograph. [0317] Example D2

A fuel cell was obtained in the same manner as in Example Dl, except that the thickness of the porous layer was set to 5 / m.

[0318] Example D3

A fuel cell was obtained in the same manner as in Example D1, except that the thickness of the porous layer was changed to 10 zm.

[0319] Example D4

A fuel cell was obtained in the same manner as in Example D1, except that the thickness of the porous layer was changed to 30 zm.

[0320] Example D5

A fuel cell was obtained in the same manner as in Example D1, except that the thickness of the porous layer was set to 40 zm.

[Table 40]

[Table 41] 40000 hours After initial power 1000 hours After 1500 hours After 2000 hours

(V) (V) (V) (V)

(\ V ^v ) NO Example. 1 0.59 0.59 0.59 0.59 0.56 Example D 2 0.54 0.54 0.54 0.54 0.51 Example D 3 0.58 0.58 0.58 0.58 0.55 Example! ) 4 0.58 0.58 0.58 0.58 0.55 Example D 5 0.55 0.55 0.55 0.55 0.52

[0321] Hereinafter, tests were performed by changing the porosity and pore diameter of the porous layer.

[0322] Example D6

The material of the porous layer made of a fluorite-type oxide containing dinoreconia was SSZ, and the composition was 90 mol% ZrO-10 mol% Sc〇. Using the respective nitrate aqueous solutions of Zr and Sc,

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing with the mixture, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 / im, the porosity was 3%, and the pore diameter was 0.1 / im. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

Example D7

The material of the porous layer made of a fluorite-type oxide containing dinoreconia was SSZ, and the composition was 90 mol% ZrO — 10 mol% Sc〇. Using the respective nitrate aqueous solutions of Zr and Sc,

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing, the mixture was sufficiently stirred to prepare a slurry. Prepared The slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1380 ° C. The thickness of the obtained porous layer was 20 / im, the porosity was 8%, and the pore diameter was 0.05 μΐη. A fuel cell was obtained in the same manner as Example D1 except for the above.

[0324] Example D8

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was l x m. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 / im, the porosity was 15%, and the pore diameter was 0.8 / im. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

[0325] Example D9

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 1 μΐη. 20 parts by weight of this powder are mixed with 100 parts by weight of a solvent (ethanol), 5 parts by weight of a solid indica (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method, and sintered at 1400 ° C. The thickness of the obtained porous layer is 20 × m, and the porosity is 20. / ο, the pore size was 2 x m. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

[0326] Example D 10

The material of the porous layer made of a fluorite-type oxide containing dinoreconia was SSZ, and its composition was 90 mol% ZrO-10 mol% ScS. Using the respective nitrate aqueous solutions of Zr and Sc,

2 2 3 After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 1 μΐη. 20 parts by weight of this powder are mixed with 100 parts by weight of a solvent (ethanol), 5 parts by weight of a solid indica (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1350 ° C. The thickness of the obtained porous layer is 20 xm, and the porosity is 30. / ο, the pore size was 1. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

Example D 11

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.2 μΐη. 30 parts by weight of this powder are mixed with 100 parts by weight of a solvent (ethanol), 2 parts by weight of a solid indica (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 / im, the porosity was 2%, and the pore diameter was 0.04 / im. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

Example D 12

2 2 3

After being prepared to have the composition described above, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 xm. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 5 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitansesquiolate) After mixing with the mixture, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method, and sintered at 1400 ° C. Got The thickness of the porous layer was 20 μπι, the porosity was 32%, and the pore diameter was 2.5 / im. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

42]

[Table 43]

[0329] Hereinafter, the material of the porous layer was tested.

[0330] Example D 13

The material of the porous layer is ScYSZ, and its composition is 90 mol% ZrO_5 mol% ScO_5 mol

2 2 3 % YO. Using the aqueous solutions of nitrates of Zr, Sc, and Y, respectively,

twenty three

After the preparation, coprecipitation with oxalic acid was performed. Except for the above, a fuel cell was obtained as in Example D1.

[0331] Example D 14

The material of the porous layer was YSZ, and the composition was 90 mol% ZrO-10 mol% YO. Zr

2 2 3

, And Y were mixed so as to have the above-mentioned composition, and then coprecipitated with oxalic acid. A fuel cell was obtained in the same manner as Example D1 except for the above.

[0332] Comparative Example D5

Cerium-containing (CeO) (SmO) between the electrolyte and the fuel-side electrode reaction layer

2 0.8 2 3 0.1

An oxide layer was provided. After using the aqueous nitrate solutions of Ce and Sm to prepare the above composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size is 0, the porosity is 18%, and the pore size is 0.

5 / m. A fuel cell was obtained in the same manner as in Example D1, except that this layer was provided.

[0333] The fuel cell obtained as described above was subjected to the Mn content, gas leak test, power generation test, and durability test on the surface of the electrolyte on the fuel electrode side. The results were as shown in the display below.

[Table 44]

[Table 45] 40000 hours After initial power supply 1000 hours after 1500 hours after 2000 hours

Estimated potential after (V) (V) (V) (V)

(V) Example D 1 0.59 0.59 0.59 0.59 0.56 Example D 13 0.58 0.58 0.58 0.58 0.55 Example D 14 0.56 0.56 0.56 0.56 0.53 Comparative example D 5 0.55 0.55 0.545 0.54 0.35

[0334] Hereinafter, the material of the air-side electrode reaction layer was tested.

Example D 15

The air-side electrode reaction layer is a layer in which (La A) (Mn Ni) 〇 and SSZ are uniformly mixed.

1— 1—

And its composition and its weight ratio are (La Sr) (Mn Ni) 0 / 90mol% Z

0.75 0.25 0.95 0.05 3

Those having r〇−10 mol% Sc〇 = 50/50 were prepared and used. La, Sr, Mn, Ni, Zr

2 2 3

After mixing with the respective nitrate aqueous solutions of Sc and Sc so as to have the above-mentioned composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 μm. A fuel cell was obtained in the same manner as Example D1 except for the above.

[0336] The fuel cell obtained as described above was subjected to a Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 46]

[Table 47] 40000 hours After initial potential After 1000 hours After 1500 hours After 2000 hours

Estimated potential (V) (V) (V) (V)

(V) Example D 1 0.59 0.59 0.59 0.59 0.56 Example D 15 0.66 0.66 0.66 0.66 0.63

[0337] Hereinafter, tests were performed with the electrolyte composition changed.

[0338] Example D 16

The electrolyte material is ScYSZ, and its composition is 90 mol% Zr〇 _5 mol% ScO _5 mol

2 2 3

% Y O. Using the nitrate aqueous solution of each of Zr, Y, and Sc,

twenty three

After the preparation, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 / m. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

[0339] Example D 17

The material of the electrolyte was SSZ, and the composition was 90 mol% ZrO-10 mol% Sc〇. Zr

2 2 3

, Sc were prepared using the respective nitrate aqueous solutions to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. A fuel cell was obtained in the same manner as Example D1 except for the above.

Example D 18

The electrolyte material is SSZ and YSZ, and the composition is 90 mol% Zr〇 _10 mol%

2

Sc 2 O and 90 mol% Zr〇-10 mol% Y〇. Air-side electrode

2 3 2 2 3

After SSZ was formed by the slurry coating method, YSZ was formed on the SSZ surface by the slurry coating method. Sintered at 1400 ° C. The thickness of each layer was 15 / im. Except for the above, a fuel cell was obtained in the same manner as in Example D1.

[0341] Example D 19

The material of the electrolyte is SSZ and YSZ, and its composition is 90mol% Zr〇 _10mol% Sc〇

22 and 90 mol% ZrO_10 mol% YO. SSZ on the surface of the air-side electrode reaction layer

3 2 2 3

Was formed by the slurry coating method, YSZ was formed on the SSZ surface by the slurry coating method, and SSZ was formed on the YSZ surface by the slurry coating method. Each layer was co-sintered at 1400 ° C. The thickness of each layer was 10 zm. Except for the above, the same as in Example D1, Battery was obtained.

[0342] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 48]

[Table 49]

[0343] Example E1

A fuel cell was obtained in the same manner as in Example D1, except that the air-side electrode reaction layer was changed to two layers as follows.

[0344] (1) Preparation of air-side electrode reaction layer (first layer)

The first layer is a layer in which (La A) Mn〇 and YSZ are uniformly mixed, and the composition and its

13

Weight ratio of La Sr Mn〇 / 90mol% ZrO—10mol% Y〇 = 50/50

0.75 0.25 3 2 2 3

Were prepared and used. La, Sr, Mn, Zr, and Y Then, after being prepared to have the above-mentioned composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 μΐη. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and an antifoaming agent (sorbitan sesquiolate) After mixing with 1 part by weight, the slurry was sufficiently stirred to prepare a slurry. The slurry viscosity was 100 mPas. This slurry was formed on a surface of an air electrode support (outside diameter: 15 mm, wall thickness: 1.5 mm, effective length: 400 mm) by a slurry coating method, and then sintered at 1400 ° C. The pore size of the first layer was 5 μm, the porosity was 28%, and the thickness was 20 μm.

[0345] (2) Preparation of air-side electrode reaction layer (second layer)

The second layer was SSZ, and the composition was 90 mol% Zr〇_10 mol% ScO. Zr and Sc

2 2 3

After mixing using the various nitrate aqueous solutions so as to have the above composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 μm. 40 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and a defoamer (sorbitan sesquiolate) After mixing with 1 part by weight, a slurry was prepared by sufficiently stirring. The slurry viscosity was 100 mPas. The slurry was formed on the surface of the first layer by a slurry coating method and then sintered at 1400 ° C. The pore size of the second layer was 1.5 μ μη, the porosity was 14%, and the thickness was 10 μΐη.

[0346] Example E2

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the porous layer was set to 5 μm. [0347] Example E3

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the porous layer was changed to 10 μm.

[0348] Example E4

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the porous layer was changed to 30 μm.

[0349] Example E5 A fuel cell was obtained in the same manner as in Example El, except that the thickness of the porous layer was changed to 40 μm.

[0350] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 50]

[Table 51]

[0351] The pore size of the second layer of the air-side electrode reaction layer was tested.

Example E6

Same as Example E1 except that the average particle size of the raw material of the second layer was 0.5 μππ, the film was formed on the surface of the first layer by the slurry coating method, and then sintered at 1350 ° C. Thus, a fuel cell was obtained. [0353] Example E7

Same as Example E1 except that the average particle size of the raw material of the second layer was 0.5 μΐη, the film was formed on the surface of the first layer by the slurry coating method, and then sintered at 1380 ° C. Thus, a fuel cell was obtained.

[0354] Example E8

The average particle diameter of the raw material of the second layer was set to 0, and the film was formed on the surface of the first layer by the slurry coating method, and then sintered at 1400 ° C in the same manner as in Example E1. A fuel cell was obtained.

Example E9

The average particle diameter of the material of the second layer was set to 2 μm, and a film was formed on the surface of the first layer by the slurry coating method, and then sintered at 1430 ° C in the same manner as in Example E1. And a fuel cell was obtained.

[0356] Example E 10

The average particle diameter of the raw material of the second layer was set to 5 _βm, and a film was formed on the surface of the first layer by a slurry coating method, and then sintered at 1430 ° C. Thus, a fuel cell was obtained.

[0357] Example E 11

The same procedure as in Example E1 was performed, except that the average particle diameter of the raw material of the second layer was set to 5 _βm, and a film was formed on the surface of the first layer by a slurry coating method and then sintered at 1450 ° C. Thus, a fuel cell was obtained.

[Table 52]

¾ i porosity-Sword H Smart ι¾: ΐΐ¾ m Μ π amount Initial electricity

(jm) (%) (xlO " ¹⁰ ms"! Pa '(wt%) (V) Example E 1 2 14 2.3 1.1 0.66 Example E 6 0.2 6 1.3 1.4 0.66 Example E 7 0.1 3 1.1 1.4 0.66 Example E 8 0.08 2 0.6 1.5 0.63 Example E 9 5 25 3.2 2.5 0.66 Example E 10 10 40 8.5 2.2 0.65 Example Ell 12 43 14.5 3.3 0.63

[Table 53]

[0358] In Example 9 one 11 compares the gas permeability of the electrolyte preferably Q≤2. 8X 10 ^_9 ms ^→ Pa preferred than a force in the range of ¹ Q≤2. Of 8 X 10 ms ^¹ Pa ¹ range Inside, On the other hand, examples E1, 6 8 are the more preferred Q≤2. 8X 10- ^1Q ms- Pa- ¹ range. Considering the gas permeability of the electrolyte, it can be seen that the pore diameter dl of the air electrode, the pore diameter d2 of the first layer, and the pore diameter d3 of the second layer are preferably dl>d2> d3.

[0359] Hereinafter, the thickness of the second layer of the air-side electrode reaction layer was tested.

[0360] Example E 12

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the second layer was 3 μm. [0361] Example El 3

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the second layer was set to 5 _βm .

Example E 14

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the second layer was 30 μm.

Example E 15

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the second layer was set to 50 μm.

[0364] Example E 16

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the second layer was 55 μm.

[0365] The fuel cell obtained as described above was subjected to the Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the table below.

54]

[Table 55] 40000 hours After initial potential After 1000 hours After 1500 hours After 2000 hours "Wt

(V) (V) (V) (V)

(V) Example E 1 0.66 0.66 0.66 0.66 0.63 Example E 12 0.62 0.62 0.62 0.62 0.59 Example E 13 0.65 0.65 0.65 0.65 0.62 Example E 14 0.66 0.66 0.66 0.66 0.63 Example E 15 0.65 0.65 0.65 0.65 0.62 Example E 16 0.62 0.62 0.62 0.62 0.59

[0366] Hereinafter, the thickness of the first layer of the air-side electrode reaction layer was tested.

[0367] Example E 17

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the first layer was _{3 μm} .

Example E 18

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the first layer was changed to 5 _μm .

[0369] Example E 19

A fuel cell was obtained in the same manner as in Example El, except that the thickness of the first layer was _{30 μm} .

[0370] Example E20

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the first layer was changed to 50 μm.

[0371] Example E 21

A fuel cell was obtained in the same manner as in Example E1, except that the thickness of the first layer was 55 × m.

[0372] The fuel cell obtained as described above was subjected to the Mn content on the fuel electrode side surface of the electrolyte, a gas leak test, a power generation test, and a durability test. The results were as shown in the table below.

[Table 56]

[Table 57]

[0373] Hereinafter, the porosity and the pore diameter of the porous layer were tested.

Example E 22

The porous layer material composed of fluorite-type oxide containing dinorecoure was SSZ, and its composition was 90 mol% ZrO-1 10 mol% ScO. Using the aqueous nitrate solutions of Zr and Sc,

2 2 3

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.3 μΐη. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing, the slurry was sufficiently stirred to prepare the slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method, and sintered at 1400 ° C. Got The thickness of the porous layer was 20 μΐη, the porosity was 3%, and the pore diameter was 0.1 / im. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

Example E 23

The porous layer material composed of a fluorite-type oxide containing dinoreconia was SSZ, and its composition was 90 mol% ZrO-10 mol% ScO. Zr

After using the aqueous solution of each of 222 and Sc to prepare the above-mentioned composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing with the mixture, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1380 ° C. The thickness of the obtained porous layer was 20 × m, the porosity was 8%, and the pore diameter was 0.05 zm. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0376] Example E 24

23 Using the respective nitrate aqueous solution of Sc,

2

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 1 μΐη. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitanses chelate) 1 After mixing with parts by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed into a film on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 x m, the porosity was 15%, and the pore size was 0. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0377] Example E 25

The porous layer material composed of a fluorite-type oxide containing dinoreconia was SSZ, and its composition was 90 mol% ZrO-10 mol% ScO. Using the aqueous nitrate solutions of Zr and Sc,

2 2 3

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Further heat treatment, grain A raw material powder having a controlled diameter was obtained. The average particle size was 1 μΐη. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 5 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitanses chelate) 1 After mixing with parts by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed into a film on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 xm, the porosity was 20%, and the pore size was 2 zm. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0378] Example E 26

The porous layer material composed of a fluorite-type oxide containing dinoreconia was SSZ, and the composition was 90 mol% ZrO-10 mol% ScO. Using the aqueous nitrate solutions of Zr and Sc,

2 2 3

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was l x m. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 5 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate ester), and 1 part by weight of an antifoaming agent (sorbitanes sesquiate) 1 After mixing with parts by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method and sintered at 1350 ° C. The thickness of the obtained porous layer was 20 μΐη, the porosity was 30%, and the pore diameter was 1.2 / im. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0379] Example E 27

After using the aqueous solution of each of 222 and Sc to prepare the above-mentioned composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. 30 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate ester), and 1 part by weight of an antifoaming agent (sorbitan sesquiolate) After mixing with the mixture, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed on the surface of the electrolyte by a slurry coating method, and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 xm, the porosity was 2%, and the pore diameter was 0.04 zm. Up Except for the above, a fuel cell was obtained in the same manner as in Example El.

Example E 28

The porous layer material composed of a fluorite-type oxide containing dinoreconia was SSZ, and the composition was 90 mol% ZrO-1 10 mol% ScO. Using the aqueous nitrate solutions of Zr and Sc,

2 2 3

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2 × m. 20 parts by weight of this powder, 100 parts by weight of a solvent (ethanol), 5 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), and 1 part by weight of an antifoaming agent (sorbitanses chelate) 1 After mixing with parts by weight, the mixture was sufficiently stirred to prepare a slurry. The prepared slurry was formed into a film on the surface of the electrolyte by a slurry coating method and sintered at 1400 ° C. The thickness of the obtained porous layer was 20 × m, the porosity was 32%, and the pore diameter was 2. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[Table 58]

[Table 59] 40000 hours Initial train 11Z 丄 υυυ υυυ f¾ ¾ 丄 oUU f ¾ ¾ time 時間

(V) Estimated potential after (V) (V) (V)

(V) Example E 1 0.66 0.66 0.66 0.66 0.63 Example E 22 0.65 0.65 0.65 0.65 0.62 Example E 23 0.66 0.66 0.66 0.66 0.63 Example E 24 0.66 0.66 0.66 0.66 0.63 Example E 25 0.66 0.66 0.66 0.66 0.63 Example E 26 0.65 0.65 0.65 0.65 0.62 Example E 27 0.62 0.62 0.62 0.62 0.59 Example E 28 0.62 0.62 0.62 0.62 0.59

[0381] Hereinafter, the materials of the first layer and the second layer of the air-side electrode reaction layer were tested.

[0382] Example Ε 29

The second layer is made of ScYSZ, and its composition is 90 mol% ZrO-5 mol% ScO-5 mol% YO

2 2 3 2 Using the aqueous nitrate solutions of Zr, Sc and Y, adjust to the above composition.

Three

After combining, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 2.m. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

Example E30

13

The weight ratio is La Sr MnO / 90mol% Zr〇 -10mol% Sc〇 = 50/50

0.75 0.25 3 2 2 3

Was prepared and used. Using the respective nitrate aqueous solutions of La, Sr, Mn, Zr, and Sc, they were prepared to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 zm. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

Example E 31

The first layer is a layer in which (La A) (Mn Ni) O and SSZ are uniformly mixed, and its composition and its weight ratio are (La Sr) (Mn Ni) 0 / 90mol% ZrO -lOmol

0.75 0.25 0.95 0.05 3 2 % Sc O = 50/50 was prepared and used. La, Sr, Mn, Ni, Zr and Sc

twenty three

Each of the aqueous nitrate solutions was blended to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 zm. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0385] Example E 32

The composition and its weight ratio are (La Sr) (Mn Ni) 0 / 90mol% ZrO -5

0.75 0.25 0.95 0.055 2 mol% ScO-5 mol% Y2O = 50/50 was prepared and used. La, Sr, Mn,

2 3 2 3

Using the nitrate aqueous solution of each of Ni, Zr, Y, and Sc, they were prepared to have the above-mentioned composition, and then coprecipitated with oxalic acid. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 5 x m. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0386] The fuel cell obtained as described above was subjected to the Mn content on the surface of the electrolyte on the fuel electrode side, a gas leak test, a power generation test, and a durability test. The results were as shown in the display below.

[Table 60]

[Table 61]

[0387] Hereinafter, the material of the porous pore layer was tested.

[0388] Example Ε 33

The material of the porous layer composed of a fluorite-type oxide containing dinoreconia was ScYSZ, and its composition was 90 mol% ZrO-5 mol% ScO-5 mol% YO. Each nitrate of Zr, Sc and Y

2 2 3 2 3

After the aqueous solution was prepared to have the above composition, coprecipitation with oxalic acid was performed. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0389] Example E 34

The material of the porous layer made of a fluorite-type oxide containing dinoreconia was YSZ, and its composition was 90 mol% ZrO-10 mol% YO. Using the respective nitrate aqueous solutions of Zr and Y,

2 2 3

After being prepared to have a composition, coprecipitation with oxalic acid was performed. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0390] Comparative Example Ε8

Cerium containing (CeO) (Sm O) between the electrolyte and the fuel-side electrode reaction layer

2 0.8 2 3 0.1

An oxide layer was provided. After using the aqueous nitrate solutions of Ce and Sm to prepare the above composition, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0, the porosity was 18%, and the pore size was 0. A fuel cell was obtained in the same manner as in Example E1, except that this layer was provided instead of the porous layer.

[Table 62] Mn amount Initial potential

(xlO-! Oms! Pa ¹ ) (wt) (V)

Example E 1 2.3 1.1 0.66

Example E 33 1.7 1.5 0.65

Example E 34 1.7 1.7 0.63

Comparative Example E 8 4.8 0.1 0.65

[Table 63]

[0391] Hereinafter, tests were performed with different configurations of the electrolyte.

[0392] Example E 35

The electrolyte material is ScYSZ, and its composition is 90 mol% ZrO -5 mol% ScO -5 mol%

2 2 3

twenty three

After combining, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0. Except for the above, a fuel cell was obtained as in Example E1.

[0393] Example E 36

2 2 3

After each Sc was mixed to have the above-mentioned composition using each nitrate aqueous solution, coprecipitation with oxalic acid was performed. Further heat treatment was performed to obtain a raw material powder having a controlled particle size. The average particle size was 0.5 μΐη. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0394] Example E 37 The electrolyte material is SSZ and YSZ, and its composition is 90 mol% Zr〇 _10 mol% ScO

22 and 90 mol% ZrO_10 mol% YO. YSZ slurry on the surface of the second layer

3 2 2 3

After forming the film by the coating method, SSZ was formed on the YSZ surface by the slurry coating method. Sintered at 1400 ° C. The thickness of each layer was 15 × m. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0395] Example E 38

22 and 90 mol% ZrO-10 mol% YO. Slurry SSZ on the second layer surface

3 2 2 3

After forming the film by the coating method, YSZ was formed on the SSZ surface by the slurry coating method. Sintered at 1400 ° C. The thickness of each layer was 15 × m. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[0396] Example E 39

22 and 90 mol% ZrO_10 mol% YO. Slurry SSZ on the second layer surface

3 2 2 3 Wi

After forming the film by the coating method, YSZ was formed on the SSZ surface by the slurry coating method, and then SSZ was formed on the YSZ surface by the slurry coating method. Each layer was co-sintered at 1400 ° C. The thickness of each layer was 10 / m. Except for the above, a fuel cell was obtained in the same manner as in Example E1.

[Table 64] Gas permeation amount Initial potential

(x lO '^ ms ^ Pa ^-1 ) (V)

Example E 1 2.3 1.1 0.66

Example E 35 1.4 1.0 0.68

Example E 36 10.1 0.4 0.68

Example E 37 1.8 0.6 0.69

Example E 38 2.5 0.6 0.69

Example E 39 2.1 0.4 0.69 [Table 65]

Estimated potential after (V) (V) (V) (V)

(V) Example E 1 0.66 0.66 0.66 0.66 0.63 Example E 35 0.68 0.68 0.68 0.68 0.65 Example E 36 0.68 0.68 0.68 0.68 0.65 Example E 37 0.69 0.69 0.69 0.69 0.66 Example E 38 0.69 0.69 0.69 0.69 0.66 Example E 39 0.69 0.69 0.69 0.69 0.66

Claims

The scope of the claims

[1] A solid oxide fuel cell comprising at least an electrolyte, an air electrode, and a fuel electrode,

The air electrode includes a perovskite-type oxide containing at least manganese, and the manganese content on the fuel electrode side surface of the layer in contact with the fuel electrode is 0.3 to 4% by weight. A solid oxide fuel cell.

2. The solid oxide fuel cell according to claim 1, wherein the layer in contact with the fuel electrode is the electrolyte.

[3] A porous layer is provided between the fuel electrode and the electrolyte,

The layer in contact with the fuel electrode is the porous layer,

The porous layer is made of a fluorite-type oxide containing zirconia and has a thickness of 5 to 40 / im.

And whose porosity is greater than that of the electrolyte

2. The solid oxide fuel cell according to claim 1, wherein

4. The solid oxide fuel cell according to claim 13, wherein an air-side electrode reaction layer is provided between the air electrode and the electrolyte.

5. The method according to claim 14, wherein the manganese content on the air electrode side surface of the electrolyte is larger than the manganese component content on the fuel electrode side surface of the electrolyte. Solid oxide fuel cell.

6. The solid oxide fuel cell according to claim 15, wherein the content of manganese on the fuel electrode side surface of the electrolyte is 0.6 to 3.5% by weight.

[7] The manganese content on the fuel electrode side surface of the electrolyte is 0.9 to 3% by weight.

The solid oxide fuel cell according to any one of claims 11 to 16.

[8] The manganese content on the air electrode side surface of the electrolyte is less than 10% by weight.

The solid oxide fuel cell according to any one of claims 17 to 17.

9. The solid oxide fuel cell according to claim 17, wherein the manganese content on the air electrode side surface of the electrolyte is less than 6% by weight.

[10] The air-side electrode reaction layer is made of a mixed conductive ceramic of a perovskite-type oxide containing manganese and nickel and an oxide containing zirconia, and is connected to open air. 10. The solid oxide fuel cell according to claim 4, wherein the solid oxide fuel cell has pores.

[11] The air-side electrode reaction layer is made of a mixed conductive ceramic of a perovskite-type oxide containing manganese and nickel oxide and cerium oxide, and has open pores communicating with each other. 10. The solid oxide fuel cell according to any one of items 4 to 9.

[12] The air-side electrode reaction layer is a mixed conductive ceramic of a perovskite-type oxide containing manganese and nickel and a perovskite-type oxide containing lanthanum and gallium, and has open pores communicating with each other. 10. The solid oxide fuel cell according to any one of claims 419, wherein:

13. The solid oxide fuel according to claim 10, wherein a content of the perovskite oxide containing manganese and nickel in the air-side electrode reaction layer is 3070% by weight. battery.

[14] The perovskite-type oxide containing manganese and nickel is (Ln A) (Mn

1— x x y 1 z

Ni) 0 (where Ln is Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, z 3

Er, Tm, Yb, and Lu force group force Any one or more of the selected forces. Indicates the misalignment force of Αί, Ca, or Sr. χί 0.15≤χ≤ 0.3, yi or 0.97≤y≤1, and z satisfies 0.02≤ζ≤0.10). The solid oxide fuel cell according to claim 1.

15. The solid oxide fuel cell according to claim 10, 13, or 14, which is a zirconia obtained by dissolving the zirconia-containing oxide power scandia.

16. The solid oxide fuel cell according to claim 10, 13 or 14, which is a zirconia in which scandia and yttria are dissolved in a solid solution containing the zirconia.

[17] The cerium oxide force formula (CeO) (J O) (where J is Sm, Gd, or Y

2 1-2X1 2 3 XI

15. The solid oxide fuel cell according to claim 11, 13 or 14, wherein XI satisfies 0.05 ≦ Χ1 ≦ 0.15).

18. The air-side electrode reaction layer according to claim 41, wherein the air-side electrode reaction layer is constituted by at least a two-layer force of a first layer on the air electrode side and a second layer on the electrolyte side. The solid oxide fuel cell according to any one of the preceding claims.

[19] The first layer is a mixture of a perovskite-type oxide containing manganese and zirconia in which scandia and / or yttria are dissolved, and has a continuous open pore,

The second layer is made of zirconia in which scandia is dissolved, and has a larger porosity than the electrolyte.

19. The solid oxide fuel cell according to claim 18, wherein

[20] The first layer is a mixture of a perovskite-type oxide containing manganese and a cerium-containing oxide, and has a continuous open pore,

19. The solid oxide fuel cell according to claim 18, wherein

[21] The first layer is a mixture of a perovskite-type oxide containing manganese and a perovskite-type oxide containing lanthanum and gallium, and having a continuous open pore,

19. The solid oxide fuel cell according to claim 18, wherein

[22] The first layer is a perovskite-type oxide containing lanthanum and cobalt, and has a continuous open pore,

19. The solid oxide fuel cell according to claim 18, wherein

[23] The first layer is a mixture of a perovskite oxide containing manganese and zirconia in which scandia and Z or yttria are dissolved, and has a continuous open pore,

The second layer is made of cerium oxide and has a higher porosity than the electrolyte.

19. The solid oxide fuel cell according to claim 18, wherein

24. The solid oxide fuel cell according to any one of claims 18 to 23, wherein a diameter of the pores of the second layer is 0.1-10 / im.

[25] The relationship between the diameter dl of the pores of the air electrode, the diameter d2 of the pores of the first layer, and the diameter d3 of the pores of the second layer and the force dl> d2> d3 25. The solid oxide fuel cell according to claim 18, which satisfies the following.

26. The solid oxide fuel cell according to claim 18, wherein the porosity of the second layer is 340%.

[27] The porosity al of the air electrode, the porosity a2 of the first layer, the porosity a3 of the second layer, and the porosity a4 of the electrolyte are al≥a2≥ 25. The solid oxide fuel cell according to claim 18, wherein the relationship a3> a4 is satisfied.

[28] The solid oxide fuel cell according to any one of claims 18 to 24, wherein the thickness of the second layer is 5 to 50 zm.

29. The solid oxide fuel cell according to any one of claims 18 to 24, wherein the thickness of the first layer is 5-50 / im.

[30] The cerium oxide constituting the second layer is represented by the formula (Ce〇) Q Ο) (where

2 1-2X1 2 3 XI

J represents Sm, Gd, or Y, and XI satisfies 0 · 05≤Χ1≤0.15), and is represented by any one of claims 23 to 29. Solid oxide fuel cell.

[31] The perovskite oxide containing manganese constituting the first layer is (La A) M

1— x x y n〇 (where Αί represents Ca or Sr, and x satisfies 0.15≤x≤0.3, yi satisfies 0.97≤y≤l

Three

31. The solid oxide fuel cell according to any one of claims 20, 21, 23 to 30, wherein the solid oxide fuel cell is lanthanum manganite represented by the following formula:

[32] The perovskite oxide containing manganese constituting the first layer is (La A) (

1— x x y

Mn Ni) 〇 (where A represents Ca or Sr, x is 0.15≤x≤0.3, y is 0.97≤

1—z z

31. The lanthanum manganite represented by y≤l, z satisfying the relationship 0.02≤z≤0.10. Solid oxide fuel cell.

[33] The cerium oxide constituting the first layer is represented by the formula (Ce〇) Q Ο, wherein J is

2 1-2X1 2 3 XI

33. Sm, Gd, or Y, and XI satisfies 0 · 05≤Χ1≤0.15), which is represented by any one of claims 20 to 24 to 32. Solid oxide fuel cell

[34] The solid oxide fuel cell according to any one of [133] to [133], wherein the electrolyte is a layer composed of dinoreconi in which scandia and / or yttria are dissolved.

[35] The electrolyte is composed of at least two layers, a layer made of zirconia in which yttria is dissolved as a solid solution on the air-side electrode reaction layer side, and a layer made of zirconium in which scandia is dissolved in the fuel electrode side. 35. The solid oxide fuel cell according to any one of claims 114, wherein the fuel cell is provided.

[36] The electrolyte is composed of at least a two-layered structure, and a layer made of dinoreconia in which scandia is dissolved as a solid solution on the air-side electrode reaction layer side, and a layer made of zirconia in which yttria is dissolved as solid solution on the fuel electrode side. 35. The solid oxide fuel cell according to claim 34, wherein:

[37] The electrolyte is composed of at least a three-layer structure, and is laminated in the order of a layer made of zirconia with solid solution of scandia, a layer made of zirconia with solid solution of yttria, and a layer made of zirconia with solid solution of scandia 35. The solid oxide fuel cell according to any one of claims 1 to 34, comprising:

[38] The air electrode is (La A) Mn〇 (where A represents Ca or Sr, and X is 0 · 15≤x

1— x x y

38. The solid oxide fuel according to any one of claims 1 to 37, wherein the solid oxide fuel is lanthanum manganite represented by ≤0.3 and y satisfies 0.97≤y≤l). battery.

39. The method according to claim 3, wherein the manganese content on the air electrode side surface of the electrolyte is larger than the manganese content on the fuel electrode side surface of the fluorite-type oxide porous layer. 39. The solid oxide fuel cell according to any one of the items 38.

40. The solid oxide fuel according to claim 39, wherein the content of the manganese component on the fuel electrode side surface of the porous layer made of the fluorite oxide is 0.6 to 3.5% by weight. battery.

[41] The manganese component on the fuel electrode side surface of the porous layer comprising the fluorite oxide The solid oxide fuel cell according to claim 39, wherein the content is 0.9 to 3% by weight.

42. The solid oxide fuel cell according to claim 3, wherein the porous layer made of the fluorite-type oxide has a porosity of 3 to 30%.

[43] The porosity al of the electrolyte, the porosity a2 of the porous layer made of the fluorite-type oxide, and the porosity a3 of the fuel electrode satisfy a relationship of al <a2 <a3. 343. The solid oxide fuel cell according to any one of claims 342, wherein

44. The solid oxide fuel cell according to any one of claims 3-43, wherein the pore size of the porous layer made of the fluorite-type oxide is 0.052 x m.

45. The solid oxide fuel cell according to claim 344, wherein the fluorite-type oxide is zirconia in which scandia is dissolved.

46. The solid oxide fuel cell according to any one of claims 3-44, wherein the fluorite-type oxide is zirconia in which scandia and yttria are dissolved.

[47] The electrolyte, wherein the electrolyte has a 3% diameter of 3 µm or more and a 97% diameter of 20 / im or less in a crystal grain size on a fuel electrode side membrane surface. Item 3. The solid oxide fuel cell according to Item 2.