KR102625579B1 - A lithium composite electrode, method of fabricating the same, and lithium secondary battery comprising the same - Google Patents

Abstract

Provided is a lithium-containing cathode comprising a metal film and lithium ion conductors and electronic conductors dispersed on one surface of the metal film, wherein some of the lithium ion conductors and some of the electronic conductors are distributed from the one surface of the metal film into the metal film. Can be impregnated.

Description

Lithium composite negative electrode, manufacturing method thereof, and lithium secondary battery comprising the same

The present invention relates to a negative electrode for a secondary battery and a secondary battery including the same, and more specifically, to a negative electrode for a lithium secondary battery and a lithium secondary battery including the same.

Lithium-ion secondary batteries are currently used as a core power source for portable electronic communication devices such as mobile phones and laptops. Compared to other energy storage methods such as capacitors and fuel cells, it has a high storage capacity, excellent charging and discharging characteristics, and high processability, so it can be used in wearable devices, electric vehicles, and energy storage systems. It is receiving great attention as a next-generation energy storage device such as ESS).

A lithium secondary battery is a battery composed of an anode, a cathode, an electrolyte that provides a path for lithium ions to move between the anode and the cathode, and a separator. It participates in oxidation and reduction reactions when lithium ions are inserted/deinserted from the anode and cathode. generates electrical energy by Lithium secondary batteries use lithium metal with high energy density as the cathode and a liquid solvent as the electrolyte. The lifespan of these lithium secondary batteries may be reduced due to dendrite phenomenon.

The problem to be solved by the present invention is to provide a lithium composite anode with improved electrical properties and a lithium secondary battery using the same.

Another problem to be solved by the present invention is to provide a lithium composite anode with improved electrical stability and service life and a lithium secondary battery using the same.

Another problem that the present invention aims to solve is to provide a method of manufacturing a lithium composite anode with a simplified manufacturing process.

The problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

The lithium composite anode according to embodiments of the present invention for solving the above-mentioned technical problems may include a metal film, and lithium ion conductors and electronic conductors dispersed on one surface of the metal film. Some of the lithium ion conductors and the electronic conductors may be impregnated into the metal film from the one surface of the metal film.

According to one embodiment, the lithium ion conductors and the electronic conductors may have a one-dimensional linear structure or a two-dimensional plate-shaped structure.

According to one embodiment, the lithium ion conductors and the electronic conductors may include nanowires, nanotubes, or nanoplates.

According to one embodiment, the lithium ion conductors may be bonded to one side of the electronic conductors.

According to one embodiment, the lithium ion conductors and the electronic conductors may have a core/shell structure in which the electronic conductors surround the outer surface of the lithium ion conductors.

According to one embodiment, a binder that crosslinks the lithium ion conductors and the electronic conductors may be further included between the lithium ion conductors and the electronic conductors.

According to one embodiment, the lithium ion conductors and the electronic conductors may not react with lithium at the driving voltage.

According to one embodiment, the lithium ion conductors are Li _{4 - x} Ge _{1 - x} P _x S ₄ (LGPS), Li _3x La _{2 /3- x} TiO ₃ (LLTO) in which lithium salt (Li salt) is mixed. , Li _{1 + x} Ti _{2 - x} M _x (PO ₄ ) ₃ , Li ₃ PS _{4 -} glass-ceramic, Li ₇ P ₃ S ₁₁ glass-ceramic, Li ₄ SnS ₄ , polyethylene oxide (PEO) or It may include mixtures thereof. The M may include aluminum (Al), gallium (Ga), indium (In), or scandium (Sc).

According to one embodiment, the electronic conductors may include stainless steel (SUS), nickel (Ni), or copper (Cu).

Lithium secondary batteries according to embodiments of the present invention for solving the above-described technical problems may include a negative electrode including a lithium composite negative electrode, a positive electrode, and a liquid electrolyte.

The method of manufacturing a lithium composite anode according to embodiments of the present invention to solve the above-described technical problems includes preparing a first solution in which lithium ion conductors and electronic conductors are mixed, adding a binder to the first solution, Preparing a second solution, applying the second solution on a current collector to form a conductive film, transferring the conductive film onto one surface of a metal film, and impregnating the conductive film with elements of the metal film. It can be included.

According to one embodiment, impregnating the conductive film into the metal film may include a pressing process or a heat treatment process.

According to one embodiment, the first solution may further include a solvent. The solvent may include N-Methyl pyrrolidone (NMP) or acetone.

According to one embodiment, applying the second solution on the current collector may include a doctor blade method, spin coating method, or bar coating method.

In the lithium composite anode according to embodiments of the present invention, electrons and lithium ions can be evenly supplied into the lithium composite anode when a secondary battery is driven. A lithium composite anode with high conductivity can be provided, and the generation of lithium dendrites within the lithium composite anode when a secondary battery is driven can be suppressed. Accordingly, the lifespan of the lithium composite anode can be improved.

In addition, the electronic conductors and lithium ion conductors may not chemically react regardless of conditions within the secondary battery, and the electronic conductors and lithium ion conductors can stably perform electronic conduction and lithium ion conduction.

The method for manufacturing a lithium composite electrode according to embodiments of the present invention can form a lithium composite electrode with improved conductivity and lifespan through a simple process such as a mixing process and a pressurization process.

1 and 2 are plan views for explaining lithium composite anodes according to embodiments of the present invention.
Figure 3 is a cross-sectional view to explain the structure of lithium ion conductors and electronic conductors.
Figure 4 is a schematic diagram for explaining a secondary battery according to embodiments of the present invention.
Figure 5 is a flowchart for explaining a method of manufacturing a lithium composite anode according to embodiments of the present invention.
Figure 6 is a photograph of the conductive film according to Experimental Example 1.
Figure 7 shows SEM images of the conductive film according to Experimental Example 1.
Figure 8 is an EDS graph of the conductive film according to Experimental Example 1.
Figure 9 is a photograph of the current collector and conductive film according to Experimental Example 2.
Figure 10 is an SEM photograph of the current collector and conductive film according to Experimental Example 2.
Figure 11 is an EDS graph of the current collector and conductive film according to Experimental Example 2.
Figure 12 is an SEM photograph of the lithium composite anode according to Experimental Example 2.
Figure 13 is a graph comparing and measuring the discharge capacity of Experimental Example 2 and Comparative Example.

In order to fully understand the configuration and effects of the present invention, preferred embodiments of the present invention will be described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, and can be implemented in various forms and various changes can be made. However, the description of the present embodiments is provided to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the present invention of the scope of the invention. Those of ordinary skill in the art will understand that the inventive concepts can be practiced in any suitable environment.

The terminology used herein is for describing embodiments and is not intended to limit the invention. As used herein, singular forms also include plural forms, unless specifically stated otherwise in the context. As used in the specification, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or elements. or does not rule out addition.

In this specification, when a film (or layer) is referred to as being on another film (or layer) or substrate, it may be formed directly on the other film (or layer) or substrate, or may form a third film (or layer) between them. or layer) may be interposed.

In various embodiments of the present specification, terms such as first, second, third, etc. are used to describe various regions, films (or layers), etc., but these regions and films should not be limited by these terms. do. These terms are merely used to distinguish one region or film (or layer) from another region or film (or layer). Accordingly, a film quality referred to as a first film quality in one embodiment may be referred to as a second film quality in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. Parts indicated with the same reference numerals throughout the specification represent the same elements.

Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted as meanings commonly known to those skilled in the art.

Hereinafter, a lithium composite anode according to the concept of the present invention will be described with reference to the drawings.

1 and 2 are plan views for explaining lithium composite anodes according to embodiments of the present invention. Figure 3 is a cross-sectional view to explain the structure of lithium ion conductors and electronic conductors.

1 and 2, the lithium composite anode 10 may include a metal film 100, electronic conductors 210, and lithium ion conductors 220.

The metal film 100 may be a thick film such as metal foil. The metal film 100 may be a lithium (Li) thick film.

Electronic conductors 210 and lithium ion conductors 220 may be disposed on one surface of the metal film 100. The electronic conductors 210 and lithium ion conductors 220 may be uniformly distributed on one surface of the metal film 100. Electronic conductors 210 and lithium ion conductors 220 may be embedded in one surface of the metal film 100 . Specifically, some of the elements of the electronic conductors 210 and lithium ion conductors 220 may be impregnated from one side of the metal film 100 toward the inside of the metal film 100 . As an example, the electronic conductors 210 and lithium ion conductors 220 may permeate between particles of the metal film 100. The interface shape of the metal film 100 impregnated with the electronic conductors 210 and lithium ion conductors 220 will be described in detail with reference to the drawings in Example 2, which will be described later. Electronic conductors 210 and lithium ion conductors 220 may be intertwined. The electronic conductors 210 and lithium ion conductors 220 may transfer lithium ions and electrons to each part of the metal film 100 .

The electronic conductors 210 may have a one-dimensional linear structure (see FIG. 1) or a two-dimensional plate-shaped structure (see FIG. 2). As an example, the electronic conductors 210 may be nanowires, nanotubes, or nanoplates. Unlike shown, the electronic conductors 210 may have a three-dimensional mass structure. The aspect ratio of the electronic conductors 210 may be 1.1 or more. The length or major axis of the electronic conductors 210 may be 1 nm to 500 nm. The mass of the electronic conductors 210 may be 20 wt% to 80 wt% relative to the total weight of the lithium composite anode. The electronic conductors 210 may not react with lithium at the driving voltage of the secondary battery (eg, 0 V to 5 V). Electronic conductors 210 may have high electronic conductivity. The electronic conductors 210 may include stainless steel (SUS), nickel (Ni), or copper (Cu). Alternatively, the electronic conductors 210 may include carbon nanotubes (CNTs) or graphene.

The lithium ion conductors 220 may have a one-dimensional linear structure (see FIG. 1), a two-dimensional plate-like structure (see FIG. 2), or alternatively, a three-dimensional mass structure. As an example, the lithium ion conductors 220 may be nanowires, nanotubes, or nanoplates. The aspect ratio of the lithium ion conductors 220 may be 1.1 or more. The length or major diameter of the lithium ion conductors 220 may be 1 nm to 500 nm. The mass of the lithium ion conductors 220 may be 20 wt% to 80 wt% based on the total weight of the lithium composite anode. The lithium ion conductors 220 may not react with lithium at the driving voltage of the secondary battery (eg, 0 V to 5 V). The lithium ion conductors 220 may have high ionic conductivity for lithium ions. The lithium ion conductors 220 may be made of a polymer conductor containing lithium salt (Li salt). For example, the lithium ion conductors 220 include Li ₂ O-SiO ₂ -TiO ₂ -P ₂ O _{5 (} LSTP), Li4-xGe1 _-x P _x S ₄ (LGPS), Li, which are mixed with lithium salts. _3x La _2/3-x TiO ₃ (LLTO), Li _{1 + x} Ti _{2 - x} M _x (PO ₄ ) ₃ , Li ₃ PS _{4 -} glass-ceramic, Li ₇ P ₃ S ₁₁ glass-ceramic, Li ₄ It may include SnS ₄ , polyethylene oxide (PEO), or mixtures thereof. Here, M may be aluminum (Al), gallium (Ga), indium (In), or scandium (Sc).

Alternatively, the electronic conductors 210 and lithium ion conductors 220 may have a bonded shape. For example, lithium ion conductors 220 may be connected to one side of the electronic conductors 210. Alternatively, as shown in FIG. 3, the lithium ion conductors 220 and the electronic conductors 210 have a core/shell in which the electronic conductors 210 surround the outer surface of the lithium ion conductors 220. shell) structure.

A binder may be provided between the electronic conductors 210 and the lithium ion conductors 220. The mass of the binder may be 1 wt% to 15 wt% based on the total weight of the lithium composite anode. The binder can crosslink the electronic conductors 210 and lithium ion conductors 220 and increase adhesion between the electronic conductors 210 and lithium ion conductors 220 and the metal film 100. The binder may include nonaqueous or aqueous materials. For example, binders include polyvinylidene fluoride (PVdF), styrene-butadiene rubber (SBR), carboxymethyl cellulose (CMC), alginate, or polyacrylic acid. : PAA) may be included. A binder may not be provided depending on your needs.

Figure 4 is a schematic diagram for explaining a secondary battery according to embodiments of the present invention. The secondary battery 1 may be a lithium secondary battery.

Referring to FIG. 4, the secondary battery 1 includes a cathode 10, an anode 20, a separator 30 present between the cathode 10 and the anode 20, a liquid electrolyte impregnated in the separator 30, It may include a battery container 40 and an encapsulation member 50 that seal the cathode 10, the anode 20, and the separator 30.

The cathode 10 may be the lithium composite cathode described in FIGS. 1 and 2. For example, the cathode 10 may include a metal film, and lithium ion conductors and electronic conductors impregnated into the metal film from the one surface of the metal film.

An anode 20 may be provided. The anode 20 may include lithium oxide. For example, the anode 20 may include lithium cobalt oxide (LCO), LI(NCM)O ₂ , or lithium manganese oxide (LMO).

The separator 30 can separate the cathode 10 and the anode 20. The separator 30 may be made of polyethylene, polypropylene, polyvinylidene fluoride (PVDF), or a multilayer film of two or more layers thereof. As an example, the separator 30 may be a mixed multilayer membrane such as a polyethylene/polypropylene two-layer separator, a polyethylene/polypropylene/polyethylene three-layer separator, or a polypropylene/polyethylene/polypropylene three-layer separator.

The liquid electrolyte may include a lithium salt dissolved in an organic solvent. For example, lithium salts include LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiAsF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , Li(CF ₃ SO ₂ ) ₂ N, LiC ₄ F ₉ SO ₃ , LiAlO ₂ , LiAlCl ₄ , It may include LiN(C _x F _{2x + 1} SO ₂ )(C _y F _{2y + 1} SO ₂ ), LiCl, LiI, and combinations thereof. Here, x and y may be natural numbers. Organic solvents include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, and ethylmethyl. It may include carbonate (ethylmethyl carbonate), butylene carbonate (butylene carbonate), or fluorinated vinyl carbonate (fluorinated vinyl carbonate).

In the lithium composite anode according to embodiments of the present invention, lithium ion conductors with high ionic conductivity to lithium ions and electronic conductors with high electronic conductivity may be impregnated into a metal film. The lithium composite negative electrode can have a smooth supply of lithium ions and electrons inside the lithium composite negative electrode, and when the secondary battery is driven, electrons and lithium ions can be evenly supplied inside the lithium composite negative electrode. Accordingly, a lithium composite anode with high conductivity can be provided, and the generation of lithium dendrites due to an imbalance between electrons and lithium ions in the lithium composite anode during operation of a secondary battery can be suppressed. As the generation of lithium dendrites in the lithium composite negative electrode is suppressed, the lifespan of the lithium composite negative electrode can be improved.

In addition, electronic conductors and lithium ion conductors may not be reactive with lithium (Li) at the operating voltage of the secondary battery (for example, 0 V to 5 V) and may not be involved in driving the secondary battery. That is, the electronic conductors and lithium ion conductors may not chemically react regardless of conditions within the secondary battery, and the electronic conductors and lithium ion conductors can stably perform electronic conduction and lithium ion conduction.

Additionally, since electronic conductors and lithium ion conductors have a one-dimensional linear structure or a two-dimensional plate-like structure, their external area can be large and the efficiency of lithium ion transfer and electron transfer can be high.

Figure 5 is a flowchart for explaining a method of manufacturing a lithium composite anode according to embodiments of the present invention. In this embodiment, detailed description of technical features overlapping with the lithium composite anode previously described with reference to FIGS. 1 to 3 will be omitted, and differences will be described in detail.

Referring to FIG. 5, a first solution can be prepared (S100). For example, the first solution can be prepared by mixing lithium ion conductors and electronic conductors in a solvent. The first solution may be a slurry. Lithium ion conductors and electronic conductors can be dispersed in a solvent through a mixer. The solvent may include N-Methyl pyrrolidone (NMP) or acetone.

A second solution may be prepared (S200). For example, a binder may be added to the first solution. The second solution may be a slurry. The viscosity of the second solution may be higher than the viscosity of the first solution. The binder may be dispersed in the first solution through a mixer.

A conductive film may be formed on the current collector (S300). For example, a second solution may be applied on the current collector. The application process of the second solution may include a doctor blade method, spin coating method, or bar coating method. The conductive film may have electronic conductors and lithium ion conductors crosslinked by a binder. The thickness of the conductive film may be 1 μm to 10000 μm. After the application process of the second solution, the solvent may be removed. As an example, a heat treatment process may be performed on the conductive film. The heat treatment process may be performed between about 70 degrees and 110 degrees.

Thereafter, the conductive film formed on the current collector may be transferred to the metal film (S400). For example, a metal film may be adhered to one side of the current collector so that the conductive film and the metal film can be in contact.

The conductive film may be impregnated into the metal film (S500). For example, the current collector and the metal film may be pressurized, allowing lithium ion conductors and electronic conductors of the conductive film between the current collector and the metal film to penetrate into the metal film. The pressing process may be performed through a press process such as roller pressing. At this time, the lithium ion conductors and electronic conductors may percolate between the metal particles of the metal film due to pressure, and some metal particles of the metal film may penetrate into the conductive film.

Alternatively, a heat treatment process is performed on the conductive film and the metal film, so that the lithium ion conductors and electronic conductors of the conductive film can penetrate into the metal film. For example, when the melting point of the conductive film is higher than the melting point of the metal film, the metal film partially melts at a temperature between the melting point of the metal film and the melting point of the conductive film, and may infiltrate between the lithium ion conductors and electronic conductors of the conductive film. . Alternatively, when the heat treatment process is performed at a temperature lower than the melting point of the metal film, metal particles on the surface of the metal film may diffuse into the conductive film.

Alternatively, a pressurizing process and a heat treatment process may be performed on the conductive film and the metal film together. At this time, the heat treatment temperature may be lower than the melting point of the metal film and the melting point of the conductive film. According to the manufacturing example described so far, the lithium composite negative electrode of Group 1 and Figure 2 can be manufactured.

The method for manufacturing a lithium composite electrode according to embodiments of the present invention can form a lithium composite electrode with improved conductivity and lifespan through a simple process such as a mixing process and a pressurization process.

According to other embodiments, the conductive film may be formed to include elements of the metal film. For example, during the manufacturing process of the second solution, metal particles (eg, lithium powder) may be added to the second solution. Thereafter, a conductive film may be formed by applying a second solution on the current collector. In this case, the conductive film may be a lithium composite electrode. The conductive film may include electronic conductors, lithium ion conductors, and metal particles. That is, a separate process for impregnating metal particles may not be necessary.

<Experimental example>

Hereinafter, the present invention is presented in more detail through experimental examples and comparative examples of the lithium composite electrode of the present invention. However, the scope of the present invention is not limited thereto.

Experiment example One

Copper (Cu) nanowire was used as an electronic conductor, and Li ₂ O-SiO ₂ -TiO ₂ -P ₂ O ₅ (LSTP) was used as a lithium ion conductor. The electronic conductor and lithium ion conductor were dispersed in N-Methyl pyrrolidone (NMP) solvent. A second solution was prepared by adding vinylidene fluoride (PVdF) as a binder to the solution. At this time, the mass ratio of copper nanowire, LSTP, and PVdF was set to 70:20:10. After the second solution was stirred to mix well, a conductive film was formed using a doctor blade method. The conductive film was formed to be about 200 μm to 300 μm. Afterwards, a heat treatment process was performed on the conductive film to remove the solvent. The heat treatment process was performed for 20 minutes at 100 degrees. A conductive film was formed as described above.

Figure 6 is a photograph of the conductive film according to Experimental Example 1, and it can be seen that the foil-shaped conductive film 200 was formed. Figure 7 shows SEM photographs of the conductive film according to Experimental Example 1, showing the nanowire-type electronic conductor and lithium ion conductor. Figures 7 (a), (b), and (c) are photographs enlarged 400 times, 1500 times, and 8000 times, respectively. Figure 8 is an elemental analysis (EDS) graph of the conductive film according to Experimental Example 1, and it can be seen that copper and lithium oxides are mixed.

Experiment example 2

The electronic conductor, lithium ion conductor, and binder were used in the same manner as in Experimental Example 1 to form a second solution, but the mass ratio of copper nanowire, LSTP, and PVdF was set to 56:40:4. The second solution was applied on the current collector using a doctor blade method to form a conductive film. Copper foil was used as the current collector. The conductive film was formed to be about 200 μm to 300 μm. A conductive film was formed as described above.

Figure 9 is a photograph of the current collector and conductive film according to Experimental Example 2, and it can be seen that the conductive film 200 was formed on the foil-shaped current collector. Figure 10 is an SEM photograph of the current collector and conductive film according to Experimental Example 2. Figure 11 is an EDS graph of the current collector and conductive film according to Experimental Example 2, and it can be seen that copper and lithium oxide are mixed.

After the metal film was placed on the current collector on which the conductive film 200 was formed, a roll pressing process and a heat treatment process were performed on the metal film and the current collector so that ion conductors and electronic conductors were impregnated into the metal film. The heat treatment process was carried out at 300 degrees. A lithium composite electrode was formed as described above.

Figure 12 is an SEM photograph of the lithium composite anode according to Experimental Example 2. Figures 12 (d) and (e) are photos enlarged 3500 times and 8000 times, respectively. In FIG. 12, it can be seen that ion conductors and electronic conductors penetrate into the interior of the metal film 100 from one side of the metal film 100, and the boundary between the metal film 100 and the conductive film 200 is not clear. You can. That is, it can be confirmed that the conductive film 200 is impregnated into the metal film 100.

Afterwards, a secondary battery was manufactured using a lithium composite electrode. Lithium cobalt oxide (LCO) was used as the anode, and an electrolyte in which LiPF ₆ was dissolved in EC/DMC was used as the electrolyte. LiPF ₆ was dissolved in EC/DMC at a concentration of 1M. A secondary battery was formed as described above.

Comparative example

A lithium foil with a thickness similar to that of the lithium composite electrode in Experimental Example 2 was used. In addition, the positive electrode and electrolyte were the same as in Experimental Example 2, and a secondary battery was formed.

Figure 13 is a graph comparing and measuring the discharge capacity of Experimental Example 2 and Comparative Example.

Referring to FIG. 13, charging and discharging were repeatedly performed on the secondary battery of Experimental Example 2 and the secondary battery of Comparative Example, and their discharge capacities were measured. As shown in FIG. 12, the discharge capacity of the secondary battery of the comparative example decreases as charging and discharging are repeated, while the discharge capacity of the secondary battery of Experimental Example 2 does not decrease as charging and discharging are repeated. You can.

That is, it can be confirmed that the service life of the lithium composite anode and the secondary battery using the same according to embodiments of the present invention is improved.

Above, embodiments of the present invention have been described with reference to the attached drawings, but those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical idea or essential features. You will understand that it exists. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

1: Secondary battery
10: lithium composite cathode 20: anode
30: Separator 40: Battery container
50: Encapsulation member
100: metal film 200: conductive conductive film
210: electronic conductor 220: lithium ion conductor

Claims (13)

metal film; and
A conductive film comprising lithium ion conductors and electronic conductors dispersed on one surface of the metal film,
The metal film and the conductive film are in contact with each other,
A lithium composite anode wherein some of the lithium ion conductors and some of the electronic conductors are impregnated into the metal film from the one surface of the metal film. According to claim 1,
A lithium composite cathode wherein the lithium ion conductors and the electronic conductors have a one-dimensional linear structure or a two-dimensional plate-like structure. According to claim 2,
The lithium composite cathode wherein the lithium ion conductors and the electronic conductors include nanowires, nanotubes, or nanoplates. According to claim 1,
The lithium ion conductors and the electronic conductors are:
A lithium composite cathode having a core/shell structure in which the electronic conductors surround the outer surfaces of the lithium ion conductors. According to claim 1,
A lithium composite negative electrode further comprising a binder that crosslinks the lithium ion conductors and the electronic conductors between the lithium ion conductors and the electronic conductors. According to claim 1,
A lithium composite cathode wherein the lithium ion conductors and the electronic conductors do not react with lithium at the driving voltage. According to claim 1,
The lithium ion conductors are Li _{4 - x} Ge _{1 - x} P _x S ₄ (LGPS), Li _3x La _{2 /3- x} TiO ₃ (LLTO), Li _{1 + x} Ti, which are mixed with lithium salt (Li salt). _{2 - x M _ _ _ _ _ _ _ _ _ _} ,
The M is a lithium composite anode containing aluminum (Al), gallium (Ga), indium (In), or scandium (Sc). According to claim 1,
The electronic conductors are lithium composite cathodes containing stainless steel (SUS), nickel (Ni), or copper (Cu).
A negative electrode comprising the lithium composite negative electrode according to any one of claims 1 to 8;
anode; and
A lithium secondary battery containing a liquid electrolyte.
preparing a first solution containing a mixture of lithium ion conductors and electronic conductors;
preparing a second solution by adding a binder to the first solution;
forming a conductive film by applying the second solution on a current collector;
transferring the conductive film onto one surface of a metal film; and
A method of manufacturing a lithium composite anode comprising impregnating an element of the metal film into the conductive film. According to claim 10,
Impregnating the conductive film into the metal film is a method of manufacturing a lithium composite anode including a pressing process or a heat treatment process. According to claim 10,
The first solution further includes a solvent,
A method of producing a lithium composite anode wherein the solvent includes N-Methyl pyrrolidone (NMP) or acetone. According to claim 10,
A method of manufacturing a lithium composite negative electrode comprising applying the second solution onto the current collector using a doctor blade method, spin coating method, or bar coating method.

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