WO2017155188A1

WO2017155188A1 - Solid oxide fuel cell and method for manufacturing same

Info

Publication number: WO2017155188A1
Application number: PCT/KR2016/014686
Authority: WO
Inventors: 배홍열; 안진수; 박영민; 배원수
Original assignee: 재단법인 포항산업과학연구원
Priority date: 2016-03-11
Filing date: 2016-12-15
Publication date: 2017-09-14
Also published as: KR20170106030A

Abstract

The present invention relates to a solid oxide fuel cell (SOFC) and, more specifically, to an SOFC comprising a reaction preventing layer between an electrolyte and an anode.

Description

Solid oxide fuel cell and manufacturing method thereof

The present invention relates to a solid oxide fuel cell (SOFC), and more particularly, to a solid oxide fuel cell including a reaction preventing layer between an electrolyte and a fuel electrode.

A fuel cell is a device that generates electricity by reacting fuel such as hydrogen or natural gas with oxygen, and is recognized as one of the main energy technologies of the future because of its high efficiency, pollution-free, and noise-free characteristics.

Solid Oxide Fuel Cells (SOFCs) use solid oxides as electrolytes to pass oxygen ions.The electrolyte materials include zirconia (ZrO ₂ ) oxides, ceria (CeO ₂ ) oxides, and lanthanum-strontium-gadolinium. Magnesium oxide (LSGM) or the like is used.

The electrolyte is yttria (Y ₂ O ₃ ), ceria (CeO ₂ ), scandia (Sc ₂ O ₃ ), gadolinium oxide (Gd ₂ O ₃ ) and the like for the purpose of improving thermal stability and ionic conductivity at high temperature. Contains some stabilizer.

The unit cell of a solid oxide fuel cell (SOFC) has the solid electrolyte described above, and is formed in such a manner that an air electrode is attached to one side and a fuel electrode is attached to the other side. As a conventional anode, a mixture of nickel oxide (NiO) and yttrium stabilized zirconia (YSZ) is used. Lanthanum-strontium-cobalt oxide (LSC), lanthanum-strontium-manganese oxide (LSM), and lanthanum-strontium- Cobalt-iron oxide (LSCF), barium-strontium-cobalt-iron oxide (BSCF), etc. are used.

Recently, a lanthanum-strontium-cobalt-iron oxide (LSCF) system or a barium-strontium-cobalt-iron oxide (BSCF) system, which is known to have superior electrochemical properties of a fuel cell than a lanthanum-strontium-manganese oxide (LSM) -based electrode Air cathodes are used a lot.

However, the lanthanum-strontium-cobalt-iron oxide (LSCF) -based or barium-strontium-cobalt-iron oxide (BSCF) -based cathode material has a property of reacting with a zirconia (ZrO ₂ ) -based electrolyte, thereby sintering the cathode. During the process and operation of the cell at high temperatures, complex ions with low ion conductivity, such as lanthanum zirconate (La ₂ Zr ₂ O ₇ ) or strontium zirconate (SrZrO ₃ ), are formed at the interface between the cathode and the electrolyte .

The formation of the reaction compound as described above decreases the rate at which oxygen ions formed in the cathode diffuse through the electrolyte and react with hydrogen in the anode, thereby degrading the overall performance of the fuel cell and causing thermal and mechanical stability by causing a difference in thermal expansion coefficient. This causes a decrease.

In this way, in order to suppress the reaction between the electrolyte and the cathode material, a reaction preventing layer is introduced between the two. As the reaction prevention layer, a ceria-based oxide doped with gadolinium (Gd), samarium (Sm), or yttrium (Y) is typically used.

The method for producing the reaction prevention layer can be largely divided into a high temperature process method and a low temperature process method.

As the high temperature process method, there is a method such as applying a sintered ceria doped with Gd or the like by screen printing method or the like and sintering as in Patent Document 1. Since the ceria-based material is poor in sintering property, if the sintering is not performed at a high temperature, the density of the ceria-based material may not be able to act as a reaction prevention layer, and the bonding strength may be reduced to peel off from the electrolyte.

However, when sintering at a high temperature to improve the sintering properties, a chemical reaction occurs between the ceria-based reaction prevention layer and the zirconia electrolyte layer to form a phase of high resistance, thereby increasing the electrical resistance of the cell Performance is degraded. For example, zirconium reacts to form high resistance cerium zirconia (Ce ₂ Zr ₂ O _{7 + x} ). Since the phase has a large activation energy of electrical conductivity according to temperature, as the operating temperature of the fuel cell decreases, the electrical conductivity decreases even more, so that the cell performance increases toward the medium and low temperature region (600 to 700 ° C). There is a problem that is sharply lowered.

On the other hand, the low temperature process method does not go through the high temperature process in the cell manufacturing process of the reaction prevention layer formation and the cathode formation. Specifically, the whole process of manufacturing a cell is performed at 1100 degrees C or less. As such, when the reaction prevention layer is formed by a low temperature process, a chemical reaction between the ceria-based reaction prevention layer and the Zirkorea electrolyte layer generated at a high temperature can be prevented, and thus phase generation can be suppressed. Therefore, since the cell produced by the low temperature process method has a small activation energy of the electric conductivity according to the temperature, the cell produced by the low temperature process exhibits excellent performance in the medium and low temperature regions because the decrease in the electric conductivity according to the temperature is alleviated. As said low temperature process method, there exist methods, such as a pulse laser, aerosol vapor deposition (patent document 2), sputtering, an electron beam vapor deposition.

However, since the low-temperature process method is deposited on an atomic basis, the interface portion between the zirconia-based electrolyte and the ceria-based reaction prevention layer is very sensitive to various process conditions. In other words, thermal, mechanical, and electrical inconsistencies at the interface between two materials increase the electrical resistance of the cell, weaken the bonding strength, and cause delamination of the intercalation, or the loose strontium (Sr) contained in the cathode layer. As a result, diffusion causes a problem such as generation of a high resistance strontium zirconia (SrZrO ₃ ) phase, causing variation in cell performance, thereby making it difficult to secure stable cell performance.

(Patent Document 1) Korean Unexamined Patent Publication No. 10-2015-0123527

(Patent Document 2) Korean Unexamined Patent Publication No. 10-2013-0065221

One aspect of the present invention is to provide a solid oxide fuel cell and a method of manufacturing the same, which has excellent performance even in the mid- and low temperature range and can secure stable cell performance by minimizing deviation.

The problem to be solved by the present invention is not limited to the above-mentioned problem, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

The present invention includes a fuel electrode, an electrolyte and an air electrode,

It includes a reaction prevention layer formed between the electrolyte and the air electrode,

It provides a solid oxide fuel cell comprising a relaxation layer formed between the electrolyte and the reaction prevention layer.

In addition, the present invention comprises the steps of preparing a half cell formed with the anode and the electrolyte;

Forming a relaxation layer on the electrolyte of the half cell using a low temperature process method;

Forming a reaction prevention layer on the alleviation layer by using a low temperature process method; And

It provides a method for producing a solid oxide fuel cell comprising the step of forming an air electrode on the reaction prevention layer.

According to the present invention, since the reaction prevention layer is formed between the electrolyte and the cathode by using a low temperature process, the chemical reaction between the ceria-based reaction prevention layer and the zirconia-based electrolyte layer generated at a high temperature can be prevented. Through this, not only excellent output performance can be secured, but also reduction of electrical conductivity can be alleviated, thereby ensuring excellent electrical performance in the mid- and low temperature regions.

In addition, by forming a relaxation layer formed between the electrolyte and the reaction prevention layer to mitigate sudden changes in the lattice constant and crystal structure between the electrolyte and the reaction prevention layer to ensure thermal and mechanical stability, as well as to ensure stable cell performance There is.

1 is a graph evaluating the performance of a fuel cell in which a reaction prevention layer is manufactured by a high temperature process method and a low temperature process method.

FIG. 2 is a photograph of observing and analyzing a phase formed at an interface between the reaction prevention layer and the electrolyte layer in a fuel cell in which the reaction prevention layer is manufactured by a low temperature process method.

3 is a graph evaluating the performance of a fuel cell in which a reaction prevention layer is manufactured by a low temperature process method.

4 is a schematic view showing a fuel cell of the present invention.

5 is a photograph of observing and analyzing the relaxation layer formed between the reaction prevention layer and the electrolyte layer in the present invention.

6 is a graph evaluating the performance of a fuel cell in which a relaxed layer of the present invention is formed.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

4, the solid oxide fuel cell of the present invention will be described in detail. 4 is for understanding the present invention, and shows one embodiment of the present invention.

The solid oxide fuel cell of the present invention includes a fuel electrode 10, an electrolyte 20, and an air electrode 30, and a reaction preventing layer 40 is formed between the electrolyte 20 and the air electrode 30. In addition, a relaxation layer 50 is formed between the electrolyte 20 and the reaction prevention layer 40. A solid oxide fuel cell generally has an electrolyte 20 in the center, and a fuel electrode 10 and an air electrode 30 on both sides of the electrolyte.

At the cathode 30 (also called anode) of the fuel cell, oxygen receives electrons and becomes oxygen ions and passes through the electrolyte 20. At the anode (10, also called cathode), oxygen ions release electrons and react with hydrogen gas. Water vapor is formed.

The electrolyte 20 of the solid oxide fuel cell should not be permeable due to its compactness, and should not have electron conductivity but high oxygen ion conductivity, and the electrode should be porous to allow gas to diffuse well and have high electron conductivity. .

The anode 10 may be divided into an anode support layer 11 and an anode functional layer 12. The anode support layer 11 and the anode functional layer 12 may be formed of a composite of nickel and stabilized zirconia. It is preferable to have a porous structure for smooth fuel gas flow.

The electrolyte uses an ion conductive solid oxide, and specifically, zirconia (ZrO ₂ ) -based oxide, ceria (CeO ₂ ) -based oxide, lanthanum-strontium-gadolinium-magnesium oxide (LSGM), and the like may be used. Of these, zirconia-based oxides are preferable, and as an example, yttrium stabilized zirconia (YSZ), scandium stabilized zirconia (ScSZ) and the like can be used. Preferably, at least one of yttrium (Y) and scandium (Sc) is zirconia included in the range of 1 at.% To 40 at.%. As will be described later, when one or more of the yttrium (Y) and scandium (Sc) is less than 1 at.%, The concentration of oxygen vacancies is too low, leading to a decrease in the oxygen ion conductivity and the electrical conductivity of the electrolyte material. On the other hand, if it exceeds 40at.%, The oxygen ion mobility may be lowered due to the incorporation of oxygen vacancies, which may cause a decrease in oxygen ion conductivity and electrical conductivity of the electrolyte material.

The cathode may be lanthanum-strontium-manganese oxide (LSM), lanthanum-strontium-cobalt oxide (LSC), lanthanum-strontium-cobalt-iron oxide (LSCF), barium-strontium-cobalt-iron oxide (BSCF), or the like. Lanthanum-strontium-cobalt-iron oxide (LSCF) may be preferably used. In addition, the lanthanum-stromium-cobalt-iron oxide (LSCF) used as the cathode material may be used alone, or may be mixed with zirconia or ceria-based oxide.

The reaction prevention layer serves to prevent the material constituting the cathode (eg, LSCF) from reacting with zirconium (Zr) constituting the electrolyte.

More specifically, the reaction layer is a sintered cathode to produce a solid oxide fuel cell, or the zirconium of the electrolyte reacts with the material constituting the cathode while the battery is operating at a high temperature, lanthanum zirconia (La ₂ Zr ₂ O ₇ ) or strontium zirconia (SrZrO ₃ ) to inhibit high resistance phase generation. The high resistance phase, such as lanthanum zirconia (La ₂ Zr ₂ O ₇ ) or strontium zirconia (SrZrO ₃ ), reduces the rate at which oxygen ions generated in the anode diffuse through the electrolyte and react with hydrogen in the cathode. By lowering, it becomes a cause of reducing overall fuel cell performance.

The material used for the reaction prevention layer is preferably ceria-based oxide, and more preferably doped ceria (GDC) doped with gadolinium (Gd), ceria (SDC) doped with samarium (Sm), or yttrium (Y) doped. Ceria (YDC), lanthanum (La) doped ceria (LDC) and the like may be used. Preferably, at least one of the gadolinium (Gd), samarium (Sm), yttrium (Y), and lanthanum (La) is included in the range of 1at.% To 40at.%. When at least one of the gadolinium (Gd), samarium (Sm), yttrium (Y), and lanthanum (La) is less than 1 at.%, The concentration of oxygen vacancies is too low to reduce the oxygen ion conductivity and the electrical conductivity of the reaction prevention layer material. Cause. On the other hand, if it is greater than 40at.%, The oxygen ion mobility may be lowered due to the incorporation of oxygen vacancies, which may cause a decrease in oxygen ion conductivity and electrical conductivity of the reaction prevention layer material.

The reaction prevention layer is preferably formed in a pore-free structure, the pores may be locally formed according to the process conditions, in this case it is preferable that the pore size has a size of 0.1㎛ or less.

The thickness of the reaction prevention layer is preferably 0.1 ~ 2.0㎛. When the thickness of the reaction prevention layer is less than 0.1 μm, not only the formation of the film quality is difficult, but also the thickness of the film may be uneven during film formation, so that the reaction between the cathode and the electrolyte may occur locally. On the other hand, if the thickness is more than 2㎛ can effectively prevent the reaction between the electrolyte and the cathode, in this case, since the reaction prevention layer itself acts as a resistance, it is preferable not to exceed 2㎛.

The mitigating layer 50 constituting the fuel cell of the present invention is positioned between the two layers to resolve structural inconsistency between the electrolyte and the reaction preventing layer, inconsistency of the thermal expansion coefficient, and the like. That is, the relaxation layer serves to alleviate the sudden change in the lattice constant and crystal structure of the electrolyte and the reaction prevention layer, not only improves the bonding strength between the two layers, but also serves to reduce the difference in the coefficient of thermal expansion thermally, It has structural robustness against mechanical change. As a result, there is a technical significance to secure stable battery performance.

The alleviation layer may be composed of a composite of an electrolyte material (M) and a reaction prevention layer material (N). The relaxation layer preferably has an electrolyte material and a reaction prevention layer in an atomic ratio (atomic%, M: N) of 1: 9-9: 1. If the atomic ratio between the materials is out of the above range, the amount of one of the two materials is so insufficient that it is difficult to form a composite, whereby the structural mismatch using the composite and the relaxation of the mismatch of the thermal expansion coefficient cannot be secured.

More specifically, the electrolyte material (M) is a zirconia-based oxide electrolyte material, it may be represented by A _x Zr _1-x O _2-δ , wherein A is at least one of yttrium (Y), scandium (Sc) And x may range from 0.01 to 0.4. On the other hand, the reaction layer material (N) is a ceria-based oxide, may be represented by B _y Ce _1-y O _2-δ , wherein B is gadolinium (Gd), samarium (Sm), yttrium (Y), lanthanum (La) may be one or more, and y may have a range of 0.01 to 0.4. When x and y are less than 0.01, the concentration of oxygen vacancies is too low, leading to a decrease in oxygen ion conductivity and electrical conductivity of the electrolyte material and the reaction prevention layer material. On the other hand, when it is larger than 0.4, oxygen ion mobility may be reduced due to coalescing of oxygen vacancies, which may cause oxygen ion conductivity and electrical conductivity of the electrolyte material and the reaction prevention layer material to decrease. On the other hand, δ means the concentration of oxygen vacancies (site where oxygen is missing in the lattice). For example, when Z is added to ZrO ₂ , the corresponding oxygen is released (if two Y are added, one oxygen is released to create an empty spot. However, the concentration of the vacancies also depends on other factors such as oxygen partial pressure. It is not represented by x / 2 because it is affected, and is usually expressed mainly by 2-δ).

It is preferable that the thickness of the relaxation layer is about 10 to 30% of the thickness of the reaction prevention layer. That is, since the thickness of the reaction prevention layer has a range of 0.1 ~ 2.0㎛, it is preferable that the thickness of the relaxation layer is 0.01 ~ 0.6㎛. When the thickness of the alleviation layer is too thin, it is difficult to secure the structural mismatch, the thermal expansion coefficient mismatch relaxation effect, while if too thick, the electrical resistance of the alleviation layer itself increases, causing a decrease in cell performance.

On the other hand, as will be described later, in the present invention, the alleviation layer and the reaction prevention layer is preferably manufactured using a low temperature process method. As the low temperature process method, there are pulse laser deposition, aerosol deposition, sputtering deposition, electron beam deposition, and the like. The heat treatment may be performed to manufacture a fuel cell after heating or deposition during the deposition process, but the temperature does not exceed 1100 ° C. is referred to as a low temperature process method. When the high temperature process method over 1100 ° C. is used for the manufacture of the alleviation layer and the reaction prevention layer, zirconium (Zr) in the electrolyte and the cerium (Ce) of the relaxation layer or the reaction prevention layer react with each other at a high temperature, and thus high resistance cerium Phases of zirconia (Ce ₂ Zr _a O _{7 + x} ) are formed, resulting in increased battery resistance due to increased resistance.

The low temperature process method for forming the alleviation layer and the reaction prevention layer may use different methods, but it is advantageous to perform the same method in terms of simplifying the process and reducing the cost.

On the other hand, it is preferable to use the electron beam deposition method which has a fast deposition rate even at low temperature in the low temperature process method, and can also deposit on a large range of large area substrate using a small target.

Hereinafter, a method of manufacturing the solid oxide fuel cell of the present invention will be described in detail.

Preferred manufacturing method in the present invention comprises the steps of preparing a half cell formed with the anode and the electrolyte; Forming a relaxation layer on the electrolyte of the half cell using a low temperature process method; Forming a reaction prevention layer on the alleviation layer by using a low temperature process method; And forming an air electrode on the reaction prevention layer.

The method for forming the anode and the electrolyte is not particularly limited in the present invention, and a half cell is manufactured by a conventional method performed in the technical field to which the present invention belongs. As a preferable example, a tape casting method or the like can be used.

For example, to form the fuel electrode, a mixture of nickel oxide (NiO) and zirconia (ZrO ₂ ) may be formed by a tape casting method, and the electrolyte layer may be formed by casting a material such as yttria stabilized zirconia (YSZ). It can form using a method.

After forming the cathode layer and the electrolyte layer, a sintering heat treatment may be performed to manufacture a half cell.

A relaxation layer is formed on the prepared electrolyte of the half cell, and a reaction prevention layer is formed on the relaxation layer. As mentioned above, it is preferable to perform the method of forming the said relaxation layer and a reaction prevention layer by a low temperature process method. The low temperature process includes pulse laser deposition, aerosol deposition, sputtering deposition, electron beam deposition, and the like. On the other hand, it is preferable to use the electron beam deposition method which has a fast deposition rate even at low temperature, and can also deposit on a large range of large area substrate using a small target.

For example, the relaxation layer and the reaction prevention layer are sequentially formed by an electron beam deposition method, but no additional heat treatment is performed. This is because the heat treatment is included in the formation of the air electrode in the future. However, even when the low temperature process method is used, heat treatment may be performed during the relaxation layer formation process or the reaction prevention layer formation process. However, the heat treatment at this time is preferably not more than 1100 ℃. If the heat treatment temperature exceeds 1100 ℃, as mentioned earlier, the formation of a high-resistance phase of cerium zirconia (Ce ₂ Zr _a O _{7 + x} ) to increase the resistance causes the battery performance degradation .

On the other hand, after forming up to the reaction prevention layer, to form an air cathode. As described above, the cathode material may be LSCF, or the like, and may be used in combination with zirconia or ceria oxide as well as single use. The method for forming the air electrode is not particularly limited in the present invention, and is based on a conventional method performed in the technical field to which the present invention belongs. In one example, the cathode material is coated by screen printing, and heat treatment is performed at a temperature in the range of 800 to 1100 ° C.

Hereinafter, embodiments of the present invention will be described in detail. The following examples are only for the understanding of the present invention, but not for limiting the present invention.

(Reference example)

The reference example is a result of analyzing the performance for each operation temperature between the cell formed the reaction layer in the high temperature process and the cell formed the reaction layer in the low temperature process in forming the reaction layer between the electrolyte and the cathode.

First, in order to form an anode (fuel electrode support and anode functional layer), a mixture of nickel oxide (NiO) and zirconia (ZrO ₂ ) was formed by tape casting. Subsequently, the electrolyte was formed by yttria stabilized zirconia (YSZ) by tape casting, followed by sintering to prepare a half cell.

In forming the anti-reaction layer on the electrolyte of the half cell, Gd-doped ceria (GDC) oxide was coated by screen printing, which is a high temperature process, and sintered by heat treatment at 1250 ° C. The low temperature process was deposited at 100 ° C. by an electron beam deposition method, and no additional heat treatment was performed.

After that, the cathode material mixed with LSCF and GDC is coated by screen printing, and sintered and heat treated at 1000 ° C. to finally manufacture the fuel cell manufactured by the high temperature process method and the fuel cell manufactured by the low temperature process method, respectively. It was.

For each fuel cell manufactured as described above, the current-voltage-output characteristics were evaluated according to the operating temperature, and the results are shown in FIGS. 1A and 1B.

As shown in (a) and (b) of FIG. 1, in the case of a fuel cell in which a reaction prevention layer is manufactured by a high temperature process method, it is confirmed that the performance decreases as the operating temperature reaches the mid-low temperature region (600 to 700 ° C.). Can be.

(Comparative Example)

The comparative example is a result of analyzing the reaction prevention layer and the electrolyte of the fuel cell in which the reaction prevention layer is manufactured by the low temperature process method based on the reference example, and manufacturing a plurality of fuel cells and evaluating the same.

A reaction prevention layer was formed on the half cell formed by the same method as the reference example by using an electron beam deposition method at 100 ° C. using a target made of GDC oxide on the electrolyte of the half cell. Thereafter, the cathode material in which the LSCF and GDC were mixed was applied by screen printing, and the fuel cell was manufactured by sintering heat treatment at 1000 ° C. Six fuel cells were fabricated in the same manner six times. In this case, the GDC oxide was a material containing 20 at.% Of GD, and the deposition thickness was about 0.3 to 0.4 μm.

With the fuel cell sample fabricated for the third time in the sixth manufacturing process, the cross section was observed and the result is shown in FIG. 2. As shown in Figure 2 (a), it was confirmed that a high resistance strontium zirconia phase was formed along the interface between the reaction prevention layer and the electrolyte. In particular, when the component is analyzed in FIG. 2 (b), it can be seen that the components of the reaction prevention layer and the electrolyte layer interface are mainly oxides of Sr and Zr.

On the other hand, for the six fuel cells manufactured as described above, it could be confirmed through Figure 3 that the variation in performance occurs. 3 is a result of separating the resistance (impedance) component according to the fuel cell frequency into a real part and an imaginary part using a plurality of elements (Z = Z '+ iZ "). Several semicircles appear in an overlapping form, and the smaller the size, the smaller the overall resistance.

From the results of FIG. 3, even in a fuel cell in which a reaction prevention layer is formed using a low temperature process method, an interface between the reaction prevention layer and the electrolyte is sensitively affected by insignificant process variables, which may cause a sudden deviation in battery performance. It could be confirmed.

(Invention example)

A half cell was prepared in the same manner as the reference example and the comparative example. Subsequently, on the electrolyte of the half cell, the target was formed of a composite of GDC and YSZ, and was deposited at 100 ° C. by electron beam deposition to form a relaxed layer. At this time, the GDC oxide was a material containing 20at.% Of Gd, and YSZ was a material containing 16at.% Of Y. Meanwhile, the atomic ratio between the GDC and YSZ was maintained at 5: 5, and the relaxed layer formed had a thickness of about 0.05 μm. No additional heat treatment was performed during the relaxation layer formation.

After the relaxation layer was formed, it was deposited at 100 ° C. by an electron beam deposition method using a target made of GDC oxide to form a reaction prevention layer. At this time, the GDC oxide was a material containing 20at.% Gd. No additional heat treatment was performed during the reaction prevention layer formation process. The thickness of the reaction prevention layer was formed to a thickness of about 0.3 ~ 0.4㎛.

Thereafter, the cathode material in which the LSCF and GDC were mixed was applied by screen printing, and the fuel cell was manufactured by sintering heat treatment at 1000 ° C. Six fuel cells were fabricated in the same manner six times.

After manufacturing six fuel cells having the form of FIG. 4 by the above method, the reaction between the reaction layer and the electrolyte of the first fuel cell was analyzed and the results are shown in FIG. 5. In FIG. 5 (a), it can be seen that a relaxation layer is formed between the reaction prevention layer and the electrolyte. In FIG. 5 (b), Ce and Zr are observed as main materials of the relaxation layer.

Meanwhile, the performance deviation of the six fuel cells is analyzed and the results are shown in FIG. 6. The result of FIG. 6 is the same as that of FIG. 3. As shown in FIG. 6, in the low temperature process method of the present invention, a fuel cell in which a mitigating layer and a reaction prevention layer are formed shows very stable cell performance regardless of manufacturing order. That is, it can be seen that the performance of the battery is very robust against the micro fluctuation factor of the process.

Claims

A fuel electrode, an electrolyte and an air electrode,

It includes a reaction prevention layer formed between the electrolyte and the air electrode,

Solid oxide fuel cell comprising a relaxation layer formed between the electrolyte and the reaction prevention layer.
The method according to claim 1,

The electrolyte is a zirconia solid oxide fuel cell containing at least one of yttrium (Y) and scandium (Sc) in the range of 1at.% To 40at.%.
The method according to claim 1,

The reaction prevention layer is a solid oxide fuel cell of ceria including at least one of gadolinium (Gd), samarium (Sm), yttrium (Y), and lanthanum (La) in a range of 1 at.% To 40 at.%.
The method according to claim 1,

The thickness of the reaction prevention layer is a solid oxide fuel cell of 0.1 ~ 2.0㎛.
The method according to claim 1,

The relaxation layer is a solid oxide fuel cell in which the electrolyte material (M) and the reaction prevention layer material (N) have an atomic ratio (at.%, M: N) of 1: 9 to 9: 1.
The method according to claim 1,

The thickness of the alleviation layer is a solid oxide fuel cell of 10-30% of the thickness of the reaction prevention layer.
Preparing a half cell on which an anode and an electrolyte are formed;

Forming a relaxation layer on the electrolyte of the half cell using a low temperature process method;

Forming a reaction prevention layer on the alleviation layer by using a low temperature process method; And

Forming an air electrode on the reaction prevention layer

Solid oxide fuel cell manufacturing method comprising a.
The method according to claim 7,

The low temperature process is any one of a pulsed laser deposition, aerosol deposition, sputter deposition and electron beam deposition method of manufacturing a solid oxide fuel cell.
The method according to claim 7,

The forming of the alleviation layer and the forming of the reaction prevention layer may be performed using the same low temperature process.
The method according to claim 7,

A method of manufacturing a solid oxide fuel cell, wherein the heat treatment is performed during or after the relaxation layer and the reaction prevention layer are formed, and the heat treatment is performed at 1100 ° C. or less.