KR20190004012A - A cathode of a lithium-air battery, a lithium-air battery including the same, and fabrication method of the cathode of the lithium-air battery - Google Patents

Abstract

The present invention relates to a manufacturing method for a positive electrode for a lithium air battery, which comprises: a step of providing a carbon sheet; and a step of forming a coating layer including a solid electrolyte on at least one surface of the carbon sheet. In addition, the step of forming a coating layer comprises: a step of providing a solid electrolyte solution on at least one surface of the carbon sheet; a step of drying the solid electrolyte solution; and a step of conducting heat treatment on the dried solid electrolyte solution. Herein, the solid electrolyte includes at least one among Li_2S-P_2S_5, Li_3.25Ge_0.25P_0.75S_4, Li_10GeP_2S_12, LiNbO_3, Li_3PO_4, Li_7La_3Zr_2O_12, Li_3BO_3, and Li_0.5La_0.5TiO_3. Therefore, the manufacturing method for a positive electrode for a lithium air battery can contribute to increase in a charging capacity and a discharging capacity.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive electrode for a lithium air battery, a lithium air battery including the positive electrode, and a method for manufacturing a positive electrode for a lithium air battery. BACKGROUND OF THE INVENTION BATTERY}

The present invention relates to a positive electrode for a lithium air battery, a lithium air battery including the positive electrode, and a method for manufacturing a positive electrode for a lithium air battery. More particularly, the present invention relates to a lithium ion battery, An anode for a lithium-air battery, a lithium-air battery including the same, and a method for manufacturing an anode for a lithium-air battery.

Lithium air cells are attracting attention as the next generation medium and large batteries for electric vehicle batteries because of their theoretical capacity more than 10 times higher than conventional lithium ion batteries. However, the instability of the liquid electrolyte used as a separation membrane, such as a discharge product having high reactivity during discharge and negative reaction with the negative electrode, hinders the reversibility of the lithium air battery and limits its service life. The liquid electrolyte is liable to be volatile and leaking, which can cause explosion and explosion at high temperature, which is a risk of running the vehicle. In the structure of the lithium air battery system, air diffusion is required to make internal and external parts of the battery and air passages. This causes leakage of liquid electrolyte and vaporized electrolyte, thereby increasing the risk of volatilization and explosion.

Recently, the stability of the lithium air battery is improved by replacing the liquid electrolyte with a solid electrolyte. The present invention proposes a positive electrode for a lithium air battery which not only has stability but also has a sufficient lithium ion passage, an oxygen passage and an electron passage, and has a high charging capacity and a discharging capacity.

Korean Patent Publication No. 10-2015-0059678

An object of the present invention is to provide a method of manufacturing an anode for a lithium air battery which can contribute to enhancement of the charging capacity and the discharge capacity.

Another object of the present invention is to provide a positive electrode for a lithium air battery capable of contributing to increase the charging capacity and the discharging capacity.

It is another object of the present invention to provide a lithium air battery capable of contributing to increase the charging capacity and the discharging capacity.

A method of manufacturing a positive electrode for a lithium air battery according to an embodiment of the present invention includes the steps of providing a carbon sheet and forming a coating layer including a solid electrolyte on at least one side of the carbon sheet. The forming of the coating layer may include providing a solid electrolyte solution on at least one surface of the carbon sheet, drying the solid electrolyte solution, and heat treating the dried solid electrolyte solution. The solid electrolyte is Li ₂ SP ₂ S ₅ , Li _{3 . 25 Ge 0 .25 P 0. 75 S} 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0. 5} La _{0 . 5,} TiO ₃ of at least one.

The solid electrolyte may include Li ₂ SP ₂ S ₅ , and the molar ratio of Li ₂ S and P ₂ S ₅ may be 50:50 to 90:10.

The step of providing the solid electrolyte solution may be performed by a dip coating method.

The drying step may be performed in a vacuum atmosphere at 80 to 150 DEG C for 2 to 4 hours.

The heat-treating step may be performed at 200 to 700 ° C in an inert atmosphere.

The method of manufacturing a positive electrode for a lithium air battery according to an embodiment of the present invention may further include a step of cooling the heat-treated solid electrolyte solution. The cooling step may be performed by natural cooling or quenching.

A positive electrode for a lithium air battery according to an embodiment of the present invention includes a carbon sheet and a coating layer provided on at least one side of the carbon sheet and including a solid electrolyte. The solid electrolyte is Li ₂ SP ₂ S ₅ , Li _{3 . 25 Ge 0 .25 P 0. 75 S} 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0. 5} La _{0 .} Of ₅ TiO ₃ may be one including at least one.

The solid electrolyte may include Li ₂ SP ₂ S ₅ , and the molar ratio of Li ₂ S and P ₂ S ₅ may be 50:50 to 90:10.

The porosity of the anode may be 50 to 75%.

The carbon content of the anode may be 60 to 80% by weight based on the anode.

A lithium air battery according to an embodiment of the present invention includes a cathode, a cathode, and an electrolyte. The anode includes a carbon sheet, and a coating layer provided on at least one surface of the carbon sheet and including a solid electrolyte. The solid electrolyte is _{Li 2 SP 2 S 5, Li} 3.25 Ge 0.25 P 0.75 S 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0 . 5} La _{0 .} Of ₅ TiO ₃ may be one including at least one. The negative electrode faces the positive electrode. The electrolyte is impregnated between the anode and the cathode.

According to the method for manufacturing a positive electrode for a lithium air battery according to an embodiment of the present invention, it is possible to provide a positive electrode capable of improving a charging capacity and a discharging capacity of the lithium air battery.

The positive electrode for a lithium air battery according to an embodiment of the present invention can improve the charging capacity and the discharging capacity of the lithium air battery.

A lithium air battery according to an embodiment of the present invention has a high charging capacity and a discharging capacity.

1 is a cross-sectional view of a lithium ion battery according to an embodiment of the present invention.
2A is a cross-sectional view of a cathode for a lithium air battery according to an embodiment of the present invention. 2B is a plan view of an anode for a lithium air battery according to an embodiment of the present invention.
3A is a cross-sectional view of a cathode for a lithium air battery according to an embodiment of the present invention.
3B is a plan view of a cathode for a lithium air battery according to an embodiment of the present invention.
4A and 4B are schematic flowcharts of a method of manufacturing an anode for a lithium air battery according to an embodiment of the present invention.
5 is a cross-sectional view sequentially illustrating a method of manufacturing a positive electrode for a lithium-ion battery according to an embodiment of the present invention.
6A and 6B are SEM photographs of the positive electrode for a lithium air battery according to Example 2. FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description of preferred embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art.

Like reference numerals are used for like elements in describing each drawing. In the accompanying drawings, the dimensions of the structures are shown enlarged from the actual for the sake of clarity of the present invention. The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Also, where a portion such as a layer, film, region, plate, or the like is referred to as being "on" another portion, this includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. On the contrary, when a part such as a layer, film, region, plate or the like is referred to as being "under" another part, it includes not only the case where it is "directly underneath" another part but also another part in the middle.

1 is a cross-sectional view of a lithium ion battery according to an embodiment of the present invention.

Referring to FIG. 1, a lithium ion battery 10 according to an embodiment of the present invention includes an anode 100, a cathode 300, and a separator 200. The lithium air battery 10 is a battery system in which lithium is used for the cathode 300 and oxygen in the air is used for the active material in the anode 100. [ In the cathode (300), oxidation and reduction of lithium occur, and in the anode (100), reduction and oxidation of oxygen introduced from the outside occur.

The following formulas (1) and (2) show reactions occurring in the cathode (300) and the anode (100) at the time of discharging the lithium air cell (10).

[Chemical Formula 1]

(Cathode) Li Li ⁺ + e ^-

(2)

_{(Positive): 2Li + + O 2 +} 2e - Li 2 O 2

The lithium metal of the cathode 300 is oxidized to generate lithium ions and electrons. The lithium ions move through the separator 200, and the electrons move to the anode 100 through the current collector and the external lead. Since the anode 100 is porous, external air can be introduced. The oxygen contained in the outside air is reduced by the electrons in the anode 100, and Li ₂ O ₂ is formed as a discharge product.

The charge reaction proceeds in the opposite way. Li ₂ O ₂ is decomposed in the anode 100 as shown in the following Chemical Formula 3 to generate lithium ions and electrons.

(3)

(Positive electrode) Li ₂ O ₂ 2Li + + O ₂ + 2e ^-

The separator 200 is impregnated between the anode 100 and the cathode 300. The separator 200 may be one comprising a solid electrolyte. The separator 200 may comprise a lithium salt. The lithium salt is dissolved in a solvent to act as a supply source of lithium ions in the battery and serves to promote the movement of lithium ions between the cathode 300 and the lithium ion and the separation membrane 200.

If this is the lithium salt is usually used in not particularly limited, for _{example, LiPF 6, LiBF 4, LiSbF} 6, LiAsF 6, LiN (SO 2 C 2 F 5) 2, Li (CF 3 SO 2) 2 N, _{LiC 4 F 9 SO 3, LiClO} 4, LiAlO 2, LiAlCl 4, LiF, LiBr, LiCl, LiI, LiB (C 2 O 4) 2, LiCF 3 SO 3, LiN (SO 2 CF 3) 2 (LiTFSI), _{LiN (SO 2 C 2 F 5} ) 2 and LiC (SO ₂ CF ₃₎ may be used one or more selected from the group consisting of _3.

2A is a cross-sectional view of a cathode for a lithium air battery according to an embodiment of the present invention. 2B is a plan view of an anode for a lithium air battery according to an embodiment of the present invention. 3A is a cross-sectional view of an anode for a lithium-ion battery according to an embodiment of the present invention, and is more specifically shown in FIG. 2A. FIG. 3B is a plan view of an anode for a lithium air battery according to an embodiment of the present invention, and is more specifically shown in FIG. 2A.

1, 2A, 2B, 3A, and 3B, an anode 100 for a lithium-air battery according to an embodiment of the present invention includes a carbon sheet 110, And a coating layer 120, 130 provided with a solid electrolyte 140.

The carbon sheet 110 is a framework structure of the anode 100. The carbon sheet 110 is an electron passage. The carbon sheet 110 is porous and comprises a plurality of pores, which are air passages.

The coating layers 120 and 130 may be provided on at least one surface of the carbon sheet 110. The coating layers 120 and 130 are movement paths of lithium ions. The coating layers 120 and 130 include a first coating layer 120 provided on the carbon sheet 110. The coating layers 120 and 130 may further include a second coating layer 130 provided under the carbon sheet 110.

The coating layers 120 and 130 include a solid electrolyte 140. The solid electrolyte 140 may be, for example, Li ₂ SP ₂ S ₅ , Li _{3 . 25 Ge 0 .25 P 0. 75 S} 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0. 5} La _{0 .} TiO ₅ may be at least one of the _three. The coating layers 120 and 130 may include Li ₂ SP ₂ S ₅ and the molar percentage of Li ₂ S and P ₂ S ₅ may be 50:50 to 90:10. If the ratio of Li ₂ S and P ₂ S ₅ is less than 60:40, the amount of lithium can not be sufficiently secured and the charging capacity and the discharging capacity can be lowered. When the ratio of Li ₂ S and P ₂ S ₅ is 90:10 , The amount of lithium may excessively interfere with the movement of oxygen and electrons.

The porosity of the anode 100 may be 50 to 75%. When the porosity of the anode 100 is less than 50%, it is difficult to ensure a sufficient air flow by interrupting the flow of air when the discharge product is formed inside the anode 100. More specifically, it is difficult to secure an oxygen flow path. Whereby the penetration rate of the electrolyte and / or air can be reduced. If the porosity of the anode 100 is more than 75%, it may be difficult to sufficiently secure the movement path of electrons and lithium ions in the anode 100.

The carbon content of the anode 100 may be 60 to 80% by weight based on the anode 100. When the carbon content of the anode 100 is less than 60% by weight based on the anode 100, it is difficult to sufficiently secure the electron transfer path in the anode 100, and the carbon content of the anode 100 is low, If it exceeds 80% by weight, it may be difficult to secure air, more specifically, a passage for oxygen.

A conventional positive electrode for a lithium air battery was formed by mixing a carbon powder and a solid electrolyte powder. Accordingly, it is difficult to sufficiently secure the pores which are the movement paths of oxygen, and the movement path of lithium and the movement path of electrons are not distinguished from each other, making it difficult to utilize the lithium ion battery having high charging capacity and discharge capacity.

The positive electrode for a lithium air battery according to an embodiment of the present invention can sufficiently secure a movement path of oxygen by using a porous carbon sheet and separately form a coating layer having a carbon sheet and a solid electrolyte, It is possible to independently secure the moving path of the motor. Accordingly, the charging capacity and the discharging capacity of the lithium ion battery can be improved.

Hereinafter, a method of manufacturing a positive electrode for a lithium air battery according to an embodiment of the present invention will be described. Hereinafter, the difference from the anode 100 for a lithium-ion battery according to an embodiment of the present invention will be described in detail below, and a portion not described will be described with reference to a cathode for a lithium air battery according to an embodiment of the present invention .

4A and 4B are schematic flowcharts of a method of manufacturing an anode for a lithium air battery according to an embodiment of the present invention. 5 is a cross-sectional view sequentially illustrating a method of manufacturing a positive electrode for a lithium-ion battery according to an embodiment of the present invention.

4A, 4B, and 5, a method of manufacturing an anode 100 for a lithium-air battery according to an embodiment of the present invention includes the steps of providing a carbon sheet 110 and forming a carbon sheet 110, And forming a coating layer (120, 130) including a solid electrolyte on at least one side of the substrate (S200). The step of forming the coating layers 120 and 130 includes the step S210 of providing the solid electrolyte solution 500 on at least one surface of the carbon sheet 110, the step S220 of drying the solid electrolyte solution 500, And a step S230 of heat treating the solid electrolyte solution 500.

First, a carbon sheet 110 is provided (S100). The carbon sheet 110 is a framework structure of the anode 100. Coating layers 120 and 130 including a solid electrolyte are formed on at least one surface of the carbon sheet 110 (S200). The step S200 of forming the coating layers 120 and 130 is not particularly limited as long as it is generally used, but it may be formed by a solution method. Step S200 of forming the coating layers 120 and 130 may include forming the first coating layer 120 on the carbon sheet 110. [ The step of forming the coating layers 120 and 130 (S200) may further include forming a second coating layer 130 below the carbon sheet 110.

Step S200 of forming the coating layers 120 and 130 includes providing the solid electrolyte solution 500 (S210). The solid electrolyte solution 500 may include, for example, Li ₂ SP ₂ S ₅ , Li _3.25 Ge _0.25 P _0.75 S ₄ , Li ₁₀ GeP ₂ S ₁₂ , LiNbO ₃ , Li ₃ PO ₄ , Li ₇ La ₃ Zr ₂ O ₁₂ , Li ₃ BO ₃ and Li _{0 . 5} La _{0 . 5} TiO ₃ may be dissolved in a solvent and a binder may be added. The solvent is not particularly limited as long as it is ordinarily used, but may be, for example, toluene. The binder is not particularly limited as long as it is commonly used, but may be, for example, a NBR (Nitrile Butadiene Rubber) binder. Step S210 of providing the solid electrolyte solution 500 may be performed by a dip coating method. The solid electrolyte solution can be evenly dispersed on the surface of the carbon sheet 110 through the dip coating method.

The solid electrolyte solution 500 may include, for example, a solid electrolyte 140, a solvent, and a binder. But the present invention is not limited thereto, and the solid electrolyte solution 500 may further include additional compounds. The solid electrolyte 140 may include, for example, Li ₂ SP ₂ S ₅ , Li _3.25 Ge _0.25 P _0.75 S ₄ , Li ₁₀ GeP ₂ S ₁₂ , LiNbO ₃ , Li ₃ PO ₄ , Li ₇ La ₃ Zr ₂ O ₁₂ , Li ₃ BO ₃ and Li _{0 . 5} La _{0 . 5,} TiO ₃ of at least one. The solid electrolyte 140 may have a molar ratio of Li ₂ S and P ₂ S ₅ of 50:50 to 90:10. If the molar ratio of Li ₂ S and P ₂ S ₅ is less than 50:50, the amount of lithium can not be sufficiently secured and the charging capacity and the discharge capacity can be lowered, and the molar percentage of Li ₂ S and P ₂ S ₅ Exceeds 90:10, the amount of lithium is excessive and does not exist in a stable phase, and precipitates as an impurity, which may interfere with the movement of lithium ions.

Next, the solid electrolyte solution 500 is dried (S220). The drying step S220 may be performed in a vacuum atmosphere at 80 to 150 DEG C for 2 to 4 hours. The solid electrolyte solution 500 may be dried within the temperature range and the time range to sufficiently remove the solvent, binder, etc. by sublimation or vaporization.

Next, the dried solid electrolyte solution 500 is heat-treated (S230). The heat-treating step (S230) may be performed at 200 to 700 占 폚 in an inert atmosphere. The solid electrolyte 140 may be fired in the heat treatment step S230. The inert atmosphere may be an atmosphere containing an inert gas, for example Ar, which is an element of Group 18.

If the heat treatment step S230 is performed at a temperature lower than 200 占 폚, the coating layers 120 and 130 may not be sufficiently heated to lower the durability of the coating layers 120 and 130. In the heat treatment step S230, The carbon sheet 110 or the coating layers 120 and 130 may be defective due to the high temperature.

Although not shown, the method of manufacturing the positive electrode (100 of FIG. 1) for a lithium air battery according to an embodiment of the present invention may further include cooling the heat-treated solid electrolyte solution. The cooling step may be performed, for example, by natural cooling or quenching.

Although not shown, the manufacturing method of the positive electrode (100 of FIG. 1) for a lithium air battery according to an embodiment of the present invention may further include a step of rolling. The contact ratio between the carbon sheet 110 and the solid electrolyte 140 can be improved in the rolling step.

In a conventional method for manufacturing a positive electrode for a lithium air battery, a carbon powder and a solid electrolyte powder are mixed to form a positive electrode. Accordingly, it is difficult to sufficiently secure the pores which are the movement paths of oxygen, and the movement path of lithium and the movement path of electrons are not distinguished from each other, making it difficult to utilize the lithium ion battery having high charging capacity and discharge capacity.

The method of manufacturing a positive electrode for a lithium air battery according to an embodiment of the present invention can sufficiently secure a movement path of oxygen by using a porous carbon sheet and can separate a coating layer having a carbon sheet and a solid electrolyte separately So that the movement path of electrons and the movement path of lithium can be independently ensured. Accordingly, the charging capacity and the discharging capacity of the lithium ion battery can be improved.

Hereinafter, the present invention will be described more specifically by way of specific examples. The following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

Example 1

A carbon sheet having a thickness of 350 탆 and a porosity of less than 87% was prepared. A solid electrolyte solution containing 80 Li ₂ S-20P ₂ S ₅ as a solid electrolyte, toluene as a solvent and NBR as a binder was prepared. At this time, based on the solid electrolyte solution, 80 Li ₂ S-20P ₂ S ₅ was contained at 25 wt%. The carbon sheet was immersed in the solid electrolyte solution, taken out, and dried at 120 캜 for 3 hours in a vacuum atmosphere. Dried and then heat-treated at 400 캜 in an Ar atmosphere to prepare a positive electrode

Example 2

The procedure of Example 1 was repeated except that 80 Li ₂ S-20P ₂ S ₅ was contained in the solid electrolyte solution in an amount of 30 wt%. SEM photographs of the positive electrode of Example 2 are shown in Figs. 6A and 6B. 6A and 6B, a carbon sheet and a coating layer formed of a solid electrolyte on a carbon sheet can be identified.

Example 3

The procedure of Example 1 was repeated except that 80 Li ₂ S-20P ₂ S ₅ was contained in the solid electrolyte solution in an amount of 35 wt%.

Comparative Example 1

The procedure of Example 1 was repeated except that the positive electrode was prepared only from the carbon sheet of Example 1.

Comparative Example 2

2 mg of carbon powder and 80 Li ₂ S-20P ₂ S ₅ powder were mixed to prepare a positive electrode.

Preparation and properties evaluation of lithium air battery

Comparative Examples 1 and 2 and Examples 1 to 3 were used as positive electrodes, respectively, and a solid electrolyte Li ₁₀ GeP ₂ S ₁₂ was used as a separation membrane and a receding metal foil to form a 500 탆 negative electrode. Porosity was measured by Porosimeter, and lithium ion conductivity and electrical resistance were measured by Impedance. Charge capacity and the discharge capacity was measured in the potential range 2V-4.6V and a current density of 0.25mA / cm ^2, oxygen (99.995%) atmosphere (2bar), 80 ℃.

Experiment result

Solid electrolyte ratio
(weight%) Porosity (%) Lithium ion conductivity (Scm ^-1 ) Electronic resistance
(m? · cm 2) Comparative Example 1 0 <87 - <10 Example 1 25 <72 2 x 10 ^-6 <35 Example 2 30 <68 3x10 ^-5 <50 Example 3 35 <53 8x10 ^-5 <86

Carbon content in anode
(weight%) Anode loading amount
(mg) Charging capacity
(mAh / cm ² ) Discharge capacity
(mAh / cm ² ) Comparative Example 1 100 12.3 0 0 Comparative Example 2 5 0.5 2.1 3.1 Example 1 75 15.4 5.0 5.2 Example 2 70 16.0 9.2 9.4 Example 3 65 16.6 4.5 4.6

Referring to Table 1, it can be confirmed that the lithium ion conductivity of Examples 1 to 3 is higher than that of Comparative Example 1. In addition, referring to Table 2, it can be confirmed that, in the case of Comparative Example 1, there is no passage of lithium ions in the positive electrode, discharge products are not generated, and thus the capacity does not develop. It can be confirmed that Examples 1 to 3 had better anode loading, charge capacity, and discharge capacity than Comparative Example 2 in which a carbon powder and a solid electrolyte powder were mixed to form a cathode.

It was confirmed that the lithium ion passage was insufficient in the case of Example 1 with less solid electrolyte coating than in Example 2, so that the charging capacity and the discharging capacity were lower than those of Example 2. [ Further, in the case of Example 3, the excess oxygen is shielded by blocking the pores in the carbon sheet with the solid electrolyte by the solid electrolyte coating. As a result, it was confirmed that the electrochemical reaction site of the discharge product was reduced and the charge capacity and the discharge capacity were lower than those of Example 2. [

In the case of Example 2, it was confirmed that the optimized porosity, the electron conductivity, and the lithium ion passage were secured, and the efficiency of the electrochemical reaction site was high, so that the maximum charging capacity and the discharge capacity were obtained.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative and non-restrictive in every respect.

Lithium air cells: 10 Bipolar: 100
Carbon sheet: 110 Coating layer: 120, 130
Solid electrolyte: 140 Membrane: 200
Cathode: 300 Solid electrolyte solution: 500

Claims (11)

Providing a carbon sheet; And
And forming a coating layer including a solid electrolyte on at least one side of the carbon sheet,
The step of forming the coating layer
Providing a solid electrolyte solution on at least one side of the carbon sheet;
Drying the solid electrolyte solution; And
And heat treating the dried solid electrolyte solution,
The solid electrolyte is Li ₂ SP ₂ S ₅ , Li _{3 . 25 Ge 0 .25 P 0. 75 S} 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0. 5} La _{0 . 5} TiO ₃ of the method for producing the lithium-air cell cathode comprises at least one. The method according to claim 1,
Wherein the solid electrolyte comprises Li ₂ SP ₂ S ₅ , and the molar ratio of Li ₂ S and P ₂ S ₅ is 50:50 to 90:10. The method according to claim 1,
Wherein the step of providing the solid electrolyte solution is performed by a dip coating method. The method according to claim 1,
The drying step
In a vacuum atmosphere, at 80 to 150 DEG C for 2 to 4 hours. The method according to claim 1,
The step of heat-
In an inert atmosphere, at 200 to 700 &lt; 0 &gt; C. The method according to claim 1,
Further comprising the step of cooling the heat-treated solid electrolyte solution,
The cooling step
Wherein the negative electrode is carried out by natural cooling or quenching. Carbon sheet; And
And a coating layer provided on at least one side of the carbon sheet and including a solid electrolyte,
The solid electrolyte is Li ₂ SP ₂ S ₅ , Li _{3 . 25 Ge 0 .25 P 0. 75 S} 4, Li 10 GeP 2 S 12, LiNbO 3, Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3 BO 3 , and Li _{0. 5} La _{0 . 5} TiO ₃ of the lithium-air cell cathode comprises at least one. 8. The method of claim 7,
Wherein the solid electrolyte comprises Li ₂ SP ₂ S ₅ , and the molar% ratio of Li ₂ S and P ₂ S ₅ is 50:50 to 90:10. 8. The method of claim 7,
The porosity of the anode
50 to 75%. 8. The method of claim 7,
The carbon content of the anode
And 60 to 80% by weight based on the positive electrode. A positive electrode according to claim 7;
A negative electrode facing the positive electrode; And
And a separator impregnated between the anode and the cathode.

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