Dry anode film, dry anode containing the same, and lithium battery

Abstract

A composite anode active material comprising a dry anode active material and a dry binder, wherein the dry anode active material comprises a core and a shell disposed along the surface of the core, the core comprising a carbon-based material; a mixture of the carbon-based material and the silicon-based active material; a composite of the carbon-based material and the silicon-based active material; or a combination thereof, the shell comprising a composite of one or more first metal oxides and a first carbon-based material, the first metal oxide disposed within a first carbon-based material matrix, and the first metal oxide having chemical formula M a O b (0

Description

[Technical Field]

[0001] The present invention relates to a dry negative electrode film, a dry negative electrode containing the same, and a lithium battery. [Background technology]

[0002] In order to meet the demands of miniaturization and increased performance in various devices, in addition to miniaturization and weight reduction of lithium batteries, increasing their energy density is also considered important. In other words, high-capacity lithium batteries are becoming increasingly important.

[0003] Electrodes manufactured from solvent-containing slurries use an excess amount of solvent during manufacturing; therefore, dry methods that eliminate the use of such organic solvents are being investigated. [Overview of the project] [Problems that the invention aims to solve]

[0004] The problem that this invention aims to solve is to provide a new dry anode film having improved cycle characteristics by reducing internal resistance and improving mechanical strength.

[0005] Another problem that the present invention aims to solve is to provide a dry anode including the dry anode film.

[0006] Another problem that the present invention aims to solve is to provide a lithium battery including the dry negative electrode. [Means for solving the problem]

[0007] According to one embodiment, a dry negative electrode active material and a dry binder are included, and the dry negative electrode active material includes a composite negative electrode active material including a core; and a shell disposed along the surface of the core, where the core includes a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof, and the shell includes a composite including one or more first metal oxides and a first carbon-based material, where the first metal oxides are disposed within a first carbon-based material matrix, the first metal oxides are represented by the chemical formula MaOb (0 < a ≤ 3, 0 < b < 4, and if a is 1, 2, or 3, b is not an integer), and M is one or more metals selected from Groups 2 to 16 of the periodic table of elements, and a dry negative electrode film is provided.

[0008] According to another embodiment, a dry negative electrode is provided, including a negative electrode current collector; and the above-described dry negative electrode film disposed on one or both surfaces of the negative electrode current collector.

[0009] The negative electrode current collector includes a substrate; and an interlayer disposed between the substrate and the dry negative electrode film, where the interlayer includes a carbon-based conductive material.

[0010] According to still another embodiment, a lithium battery is provided, including a positive electrode, a negative electrode, and an electrolyte disposed between the positive electrode and the negative electrode, where the negative electrode is the above-described dry negative electrode, and the electrolyte includes a liquid electrolyte, a solid electrolyte, or a combination thereof.

Advantages of the Invention

[0011] According to one embodiment, the internal resistance of the dry negative electrode film is reduced and the mechanical properties are improved, so that the initial efficiency and cycle characteristics of a lithium battery employing such a dry negative electrode film are improved.

Brief Description of the Drawings

[0012] [Figure 1] It is a schematic cross-sectional view of a dry negative electrode active material according to one embodiment. [Figure 2]This is a schematic cross-sectional view of a dry anode active material according to another embodiment. [Figure 3A] This is a drawing showing the structure of a dry anode-separator subassembly according to one embodiment. [Figure 3B] This is a drawing showing the structure of a dry anode-separator subassembly according to another embodiment. [Figure 4A] This is a cross-sectional view showing a laminated structure of a dry negative electrode for a lithium battery according to one embodiment. [Figure 4B] This is a cross-sectional view showing a laminated structure of a dry negative electrode for a lithium battery according to another embodiment. [Figure 4C] This is a cross-sectional view showing a laminated structure of a dry negative electrode for a lithium battery according to another embodiment. [Figure 5] This is a schematic diagram of a lithium battery according to one embodiment. [Figure 6] This is a schematic diagram of a lithium battery according to another embodiment. [Figure 7] This is a schematic diagram of a lithium battery according to yet another embodiment. [Modes for carrying out the invention]

[0013] Various embodiments are illustrated in the accompanying drawings. However, the present invention can be embodied in various other forms and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided so as to make this disclosure thorough and complete, and will fully convey the scope of the present invention to those who are ordinaryly skilled in the art. The same reference numerals in the drawings refer to the same components.

[0014] When one component is said to be "on top of" another, it can be understood that it may also be directly above the other component, or that other components may be interposed between them. In contrast, when one component is said to be "directly above" another, there is no component interposed between them.

[0015] Terms such as “First,” “Second,” and “Third” may be used herein to describe a variety of components, elements, regions, layers, and / or areas, but these components, elements, regions, layers, and / or areas should not be limited by these terms. These terms are used solely to distinguish one component, element, region, layer, or area from other elements, elements, regions, layers, or areas. Thus, the first component, element, region, layer, or area described below may also refer to the second component, element, region, layer, or area without exception as taught herein.

[0016] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The singular form as used herein includes plural forms, including “at least one,” unless the content expressly indicates otherwise. “At least one” should not be construed as limiting to the singular. As used herein, “and / or” includes all any combination of one or more of the list items. “including” and / or “including” as used in the detailed description specify the presence of the expressed features, regions, integers, stages, operations, components, and / or ingredients, and do not exclude the presence or addition of one or more other features, regions, integers, stages, operations, components, ingredients, and / or groups thereof.

[0017] Spatially relative terms such as “down,” “underside,” “bottom,” “up,” “top,” and “upper” may be used herein to facilitate the description of the relationship between one component or feature and other components or features. Spatially relative terms will be understood to be intended to include different orientations of the device when used or operated in the direction illustrated in the drawings. For example, if the device in the drawings is inverted, a component described as “below” or “below” another component or feature will be oriented “above” the other component or feature. Thus, the exemplary term “down” may encompass both the up and down directions. The device may be positioned in other orientations (rotated by 90° or in other directions), and the spatially relative terms used herein may be interpreted accordingly.

[0018] Unless otherwise specifically defined, all terms used herein (including technical and scientific terms) have the same meaning as those generally understood by a person of ordinary skill in the art to which this disclosure pertains. Furthermore, it will be understood that terms as defined in commonly used dictionaries should be interpreted to have a meaning consistent with the meaning in the context of the relevant technology and the content of this disclosure, and should not be interpreted in an idealized or overly formal sense.

[0019] Exemplary embodiments are described herein with reference to cross-sectional views which are schematic diagrams of idealized embodiments. Thus, deformation from the illustrated shape should be expected as a result of, for example, manufacturing techniques and / or tolerances. Accordingly, the embodiments described herein should not be construed as being limited to specific shapes of regions as illustrated herein, and should include, for example, deviations of shape caused by manufacturing. For example, a region illustrated or described as flattened may typically be rough and / or have nonlinear features. Furthermore, sharply illustrated corners may be rounded. Accordingly, the regions illustrated in the drawings are essentially schematic, and their shapes are not intended to illustrate the exact shape of the region and are not intended to limit the scope of the claims.

[0020] "Group" refers to a group of elements in the periodic table according to the International Union of Pure and Applied Chemistry (IUPAC) classification system of groups 1-18.

[0021] As used herein, the term "dry" refers to a state in which a material does not function properly when in contact with or without a solvent, such as a process solvent. For example, a dry conductive material refers to a conductive material that functions correctly without contact with a solvent, or a conductive material that does not contain a solvent. For example, a dry binder refers to a conductive material that functions correctly without contact with a solvent, or a binder that does not contain a solvent. For example, a binder that is not mixed with a solvent and is in a liquid state at room temperature is called a dry binder.

[0022] In this specification, "particle size" refers to the average diameter if the particle is spherical, and to the average major axis length if the particle is non-spherical. Particle size can be measured using a particle size analyzer (PSA). "Particle size" is, for example, the average particle size. "Average particle size" is, for example, the median particle size, D50.

[0023] D50 is the particle size that corresponds to the 50% cumulative volume, calculated from the smallest particle size in the particle size distribution measured by laser diffraction.

[0024] D90 is the particle size that corresponds to the 90% cumulative volume, calculated from the smallest particle size in the particle size distribution measured by laser diffraction.

[0025] D10 is the particle size corresponding to the 10% cumulative volume, calculated from the smallest particle size in the particle size distribution measured by laser diffraction.

[0026] The average particle size (D50) can be measured by a method suitable for those skilled in the art, for example, by a particle size analyzer, transmission electron microscope image, scanning electron microscope, or field emission scanning electron microscope (FE-SEM). In some embodiments, data analysis is performed using a dynamic light scattering analyzer to count the number of particles for each particle size range, thereby easily determining the average particle size (D50) value through the following calculation. In the present invention, "diameter" refers to the particle size or average particle size when the particle is spherical, and when the particle is spherical, "diameter" refers to the major axis length or average major axis length.

[0027] In this invention, "metal" includes both metals and metalloids such as silicon and germanium, in either an elemental or ionic state.

[0028] In this invention, "alloy" means a mixture of two or more metals.

[0029] In this invention, "electrode active material" means an electrode material that can be lithium-treated and delithiated.

[0030] In this invention, "positive electrode active material" means a positive electrode material that can be lithium-ionized and delithiated.

[0031] In this disclosure, "negative electrode active material" means a negative electrode material that can be lithium-treated and delithi-treated.

[0032] In this invention, "lithification" and "lithification" refer to the process of adding lithium to the electrode active material.

[0033] In this invention, "desitization" and "to delithiate" refer to the process of removing lithium from the electrode active material.

[0034] In this invention, "charging" and "to charge" refer to the process of providing electrochemical energy to a battery.

[0035] In this invention, "discharge" and "to discharge" refer to the process of removing electrochemical energy from a battery.

[0036] In this invention, "positive electrode" and "cathode" refer to electrodes in which electrochemical reduction and lithiumization occur during the discharge process.

[0037] In this invention, "negative electrode" and "anode" refer to electrodes in which electrochemical oxidation and delithiation occur during the discharge process.

[0038] While specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently anticipated or foreseeable may arise for the applicant or those skilled in the art. Accordingly, the claims of the application and any modifications thereof are intended to include all such alternatives, modifications, variations, improvements, and substantial equivalents.

[0039] Hereinafter, the dry-type negative electrode film, the dry-type negative electrode including the same, and the lithium battery according to the exemplary embodiments will be described in more detail.

[0040] When the active material, the conductive material, and the binder are dry-mixed for manufacturing the negative electrode plate with a dry-type negative electrode, there is a problem that the conductive material of the nanoparticles is bound to the binder, the conductive material is excessively aggregated in the binder, and then binds to the active material, resulting in a non-uniform mixture of the active material, the conductive material, and the binder, high electrode plate resistance, and low tensile strength. In contrast, by using the manufacturing method according to an embodiment, a dry-type negative electrode film in which the binder and the conductive material are uniformly bound to the surface of the active material in the manufacturing process of the dry-type electrode plate is provided, which not only improves the resistance reduction effect but also provides a dry-type negative electrode film with improved tensile strength, a dry-type negative electrode including the same, and a lithium battery.

[0041] The dry-type negative electrode film according to an embodiment includes a dry-type negative electrode active material and a dry-type binder, the dry-type negative electrode active material includes a core; and a shell disposed along the surface of the core, the core includes a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof, the shell includes a composite including one or more first metal oxides and a first carbon-based material, the first metal oxide is disposed in the first carbon-based material matrix, the first metal oxide is represented by the chemical formula MaOb (0 < a ≤ 3, 0 < b < 4, if a is 1, 2, or 3, b is not an integer), and M is one or more metals selected from Groups 2 to 16 of the periodic table.

[0042] Referring to FIG. 1, the dry-type negative electrode active material 100 includes a core 10 and a shell 20 disposed continuously or discontinuously along the surface of the core 10.

[0043] The core 10 includes a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof, and the shell 20 can cover all or part of the core 10.

[0044] The shell 20 comprises a first metal oxide 21 and a first carbon-based material 22. The dry anode active material is, for example, an electrode active material that is not impregnated, dissolved, or dispersed in a process solvent during the dry anode film manufacturing process.

[0045] The dry anode active material has a core / shell structure, and the shell contains a primary carbon-based material, which allows for more uniform mixing of the dry anode active material and the dry binder. Therefore, aggregation of the dry binder within the dry anode film is suppressed, and the dry binder can be distributed uniformly in three dimensions. By suppressing local resistance regions within the dry anode film, the imbalance in current density is reduced, which can decrease the overall internal resistance of the dry electrode film.

[0046] The presence of a core / shell structure in the dry anode active material, with the shell containing a primary carbon-based material, can reduce the interfacial resistance between the dry anode active materials. The presence of a core / shell structure in the dry anode active material, with the shell containing a primary carbon-based material, can reduce the internal resistance of the dry anode film. The presence of a core / shell structure in the dry anode active material, with the shell containing a primary carbon-based material, can improve the bonding strength between the dry anode active material and the dry binder. The presence of a core / shell structure in the dry composite anode active material, with the shell containing a primary carbon-based material, can improve the mechanical properties of the dry anode film, such as its tensile strength. The reduction in the internal resistance of the dry anode film and the improvement in its mechanical properties can improve the cycle characteristics of a lithium battery containing such a dry anode film.

[0047] The inclusion of a primary metal oxide in the shell improves ionic conductivity compared to a shell made of carbon-based material, and as a result, the ionic conductivity of the dry anode active material can be improved.

[0048] The dry anode active material has a core / shell structure, and the shell can be arranged continuously or discontinuously along the surface of the core. The shell can be further uniformly arranged on the core by including a first metal oxide arranged in a first carbon-based material matrix. The shell can be further uniformly arranged on the core without aggregation by being introduced onto the core from a composite containing a first metal oxide arranged in a first carbon-based material matrix, for example. The uniformly arranged shell on the core can prevent side reactions caused by contact between the core and the electrolyte by effectively blocking contact between the core and the electrolyte. In addition, the formation of a resistive layer on the core surface can be suppressed by suppressing cation mixing caused by contact between the core and the electrolyte. Furthermore, the introduction of the shell onto the core can suppress the elution of transition metal ions from the core in cores containing transition metals. The first carbon-based material is, for example, a crystalline carbon-based material. The first carbon-based material is, for example, a carbon-based nanostructure. The first carbon-based material is, for example, a carbon-based two-dimensional nanostructure. The first carbon-based material is, as an example, graphene. For example, a shell containing graphene and / or its matrix is ​​flexible, so it can easily accommodate volume changes in the dry anode active material during charging and discharging, thereby suppressing crack formation within the dry anode active material. Graphene has high electronic conductivity, so the interfacial resistance between the dry anode active material and the electrolyte is reduced. Therefore, even with the introduction of a graphene-containing shell, the increase in the internal resistance of the lithium battery can be suppressed. On the other hand, conventional carbon-based materials that do not contain the first metal oxide are easily aggregated, making it difficult to uniformly distribute them on the core of the dry anode active material. Furthermore, the first carbon-based material matrix, for example, derived from a graphene matrix, has a relatively lower density and higher porosity compared to conventional carbon-based materials derived from graphite-based materials.

[0049] The dry-type negative electrode active material has a core / shell structure. The shell contains a first metal oxide, and the metal contained in the first metal oxide is, for example, one or more selected from Al, Nb, Mg, Sc, Ti, Zr, V, W, Mn, Fe, Co, Pd, Cu, Ag, Zn, Sb, and Se. The first metal oxide is, for example, Al2O z (0 < z < 3), NbO x (0 < x < 2.5), MgO x (0 < x < 1), Sc2O z (0 < z < 3), TiO y (0 < y < 2), ZrO y (0 < y < 2), V2O z ((0 < z < 3), WO y (0 < y < 2), MnO y (0 < y < 2), Fe2O z (0 < z < 3), Co3O w (0 < w < 4), PdO x (0 < x < 1), CuO x (0 < x < 1), AgO x (0 < x < 1), ZnO x (0 < x < 1), Sb2O z (0 < z < 3), and SeO y (0 < y < 2), and is one or more selected therefrom. By arranging such a first metal oxide in the first carbon-based material matrix, the uniformity of the shell disposed on the core is improved, and the high-voltage resistance of the dry-type negative electrode active material is further improved. The shell contains, for example, Al2Ox (0 < x < 3) as the first metal oxide.

[0050] The shell may further contain one or more second metal oxides. The second metal oxide is, for example, the chemical formula M a O c(0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer), and M is one or more metals selected from Groups 2 to 13, Group 15, and Group 16 of the periodic table. The second metal oxide may, for example, contain the same metal as the first metal oxide. The ratio c / a of a and c of the second metal oxide may have a value even larger than the ratio b / a of a and b of the first metal oxide. For example, c / a > b / a. The second metal oxide may be disposed within the first carbon-based material matrix. The second metal oxide is selected from, for example, Al2O3, NbO, NbO2, Nb2O5, MgO, Sc2O3, TiO2, ZrO2, V2O3, WO2, MnO2, Fe2O3, Co3O4, PdO, CuO, AgO, ZnO, Sb2O3, and SeO2. The first metal oxide is, for example, a reduction product of the second metal oxide. The first metal oxide is obtained by reducing some or all of the second metal oxide. Therefore, the first metal oxide has a lower oxygen content and a lower oxidation number of the metal compared to the second metal oxide. For example, the shell contains Al2Ox (0 < x < 3) as the first metal oxide and Al2O3 as the second metal oxide.

[0051] The shell contains, for example, one or more selected from the first metal oxide and the second metal oxide, and the particle size of one or more selected from the first metal oxide and the second metal oxide is, for example, 0.1 nm to 100 nm, 0.5 nm to 100 nm, 1 nm to 100 nm, 1 nm to 50 nm, 1 nm to 3 nm, 5 nm to 30 nm, or 10 nm to 30 nm. By having such a nano-scale particle size for the first metal oxide and / or the second metal oxide, it can be more uniformly distributed within the first carbon-based material matrix. If the particle size of one or more of the first metal oxide and the second metal oxide increases excessively, the internal resistance of the composite negative electrode active material may increase due to an increase in the shell thickness. If the particle size of one or more of the first metal oxide and the second metal oxide decreases excessively, uniform dispersion becomes difficult.

[0052] The shell comprises a first metal oxide and / or a second metal oxide, and may include a first carbon-based material. The first carbon-based material may be positioned in a direction that protrudes from the surface of the first metal oxide and / or the second metal oxide. The first carbon-based material positioned in a direction that protrudes from the surface of the first metal oxide and / or the second metal oxide may be positioned in a direction that protrudes from the surface of the first metal oxide and / or the second metal oxide by growing directly from the surface of the first metal oxide and / or the second metal oxide. Examples of the first carbon-based material positioned in a direction that protrudes from the surface of the first metal oxide and / or the second metal oxide are carbon-based two-dimensional nanostructures, carbon-based flakes, or graphene.

[0053] The shell thickness is 5 μm or less, for example, 0.1 nm to 5 μm, 0.5 nm to 5 μm, 1 nm to 5 μm, 1 nm to 1 μm, 1 nm to 500 nm, 1 nm to 200 nm, 1 nm to 100 nm, 1 nm to 50 nm, 1 nm to 30 nm, or 1 nm to 20 nm. Having a shell thickness in such a range can further improve the electronic conductivity of the dry anode containing the dry anode active material and further reduce its internal resistance.

[0054] The shell may have a single-layer or multi-layer structure. The multi-layer structure may, for example, have two, three, or four layers. In the multi-layer structure, for example, each layer may contain a different type of metal in the first metal oxide.

[0055] The shell content is, for example, 5 wt% or less, 0.01 wt% to 5 wt%, 0.01 wt% to 3 wt%, 0.01 wt% to 2 wt%, or 0.01 wt% to 1 wt% of the total weight of the dry anode active material. The first metal oxide content is, for example, 3 wt% or less, 0.006 wt% to 3 wt%, 0.06 wt% to 1.8 wt%, 0.006 wt% to 1.2 wt%, or 0.006 wt% to 0.6 wt% of the total weight of the dry anode active material. The inclusion of shell and first metal oxide within such content ranges in the dry anode active material further improves the cycle characteristics of the lithium battery.

[0056] The shell, which is arranged along the surface of the core, is, for example, a dry coating layer. The shell can be introduced onto the core by a dry method, such as milling. The shell, which is arranged along the surface of the core, may include, for example, one or more selected from a composite containing a first metal oxide and a first carbon-based material, such as graphene, and the milling results of the composite. The first metal oxide is arranged in a matrix of the first carbon-based material, such as a graphene matrix.

[0057] The shell is manufactured from a composite comprising, for example, a first metal oxide and a first carbon-based material, such as graphene. The composite may further contain a second metal oxide in addition to the first metal oxide. The composite may, for example, contain two or more first metal oxides. The composite may, for example, contain two or more first metal oxides and two or more second metal oxides.

[0058] The composite may contain one or more selected from the first and second metal oxides. The particle sizes of the one or more selected from the first and second metal oxides may be 0.1 nm to 100 nm, 0.5 nm to 100 nm, 1 nm to 100 nm, 1 nm to 50 nm, 1 nm to 30 nm, 5 nm to 30 nm, or 10 nm to 30 nm. Having particle sizes in such nanoscale ranges allows the first and / or second metal oxides to be more uniformly distributed within the first carbon-based material matrix of the composite. Thus, such a composite can be uniformly coated onto a core without aggregation to form a shell. Furthermore, having particle sizes in such ranges allows the first and / or second metal oxides to be more uniformly arranged on the core. Thus, uniform arrangement of the first and / or second metal oxides on the core allows for more effective exhibit of dielectric strength. The particle sizes of the first and / or second metal oxides are measured, for example, using laser diffraction or dynamic light scattering measuring devices. The particle size is measured, for example, using a laser scattering particle size analyzer (e.g., HORIBA LA-920), and is the median particle size (D50) value when 50% of the particles are accumulated from the smallest particle side in terms of volume. One or more uniformity deviations selected from the first metal oxide and / or the second metal oxide are 3% or less, 2% or less, or 1% or less.

[0059] The degree of uniformity can be determined, for example, by X-ray photoelectron spectroscopy (XPS). Therefore, one or more selected metal oxides from the first and second metal oxides can be uniformly distributed within the composite with deviations of 3% or less, 2% or less, or 1% or less.

[0060] The dry anode active material includes a core, which includes, for example, a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof.

[0061] A mixture of a carbon-based material and a silicon-based active material or a composite of a carbon-based material and a silicon-based active material, wherein the content of the silicon-based active material is 5 to 20% by weight, 7 to 18% by weight, 10 to 17% by weight, or 10 to 15% by weight based on 10% by weight of the total weight of the mixture of the carbon-based material and the silicon-based active material or the composite of the carbon-based material and the silicon-based active material.

[0062] The carbon-based material is crystalline carbon, amorphous carbon, or a combination thereof, and the crystalline carbon is one or more selected from the group consisting of natural graphite, artificial graphite, graphene, fullerene, and carbon nanotubes, and the amorphous carbon is one or more selected from the group consisting of pitch carbon, soft carbon, hard carbon, mesophase pitch carbide, calcined coke, and carbon fiber.

[0063] The precursor of the amorphous carbon is a coal-based pitch, mesophase pitch, petroleum-based pitch, coal-based oil, petroleum-based heavy oil, or a polymer resin such as a phenolic resin, furan resin, or polyimide resin.

[0064] The silicon-based active material is a Si alloy, a silicon-containing structure, a silicon-containing compound, or a combination thereof.

[0065] The silicon-containing compound is SiO2, SiO x (0 < x < 2), SiC, or a combination thereof, and the silicon-containing structure includes a silicon composite structure.

[0066] According to one embodiment, the silicon-based active material includes a silicon composite structure. The silicon composite structure is a silicon-carbon composite or may include a silicon-carbon composite.

[0067] The silicon-carbon composite is a silicon-carbon composite including silicon particles and a first carbon-based material, a silicon-carbon composite including a core in which silicon particles and a second carbon-based material are mixed and a third carbon-based material surrounding the core, or a combination thereof.

[0068] The first to third carbon-based materials are, independently of each other, crystalline carbon, amorphous carbon, or a combination thereof. The silicon-carbon composite comprises a core containing silicon particles and crystalline carbon, and an amorphous carbon coating layer located on the surface of the core.

[0069] When the aforementioned silicon-carbon composite is used as the silicon-based active material, the secondary battery can exhibit high capacity while also demonstrating stable cycle characteristics.

[0070] In the silicon-carbon composite comprising the silicon particles and the first carbon-based material, the content of the silicon particles is 30% to 70% by weight, 30% to 60% by weight, for example, 40% to 50% by weight. Alternatively, the silicon-based active material may include a silicon-carbon composite comprising a core in which silicon particles and a second carbon-based material are mixed, and a third carbon-based material surrounding the core. By utilizing such a silicon-carbon composite, secondary batteries can achieve very high capacity while improving capacity retention, and in particular, improving high-temperature lifetime characteristics. In this specification, average particle size (D50) means the diameter of a particle whose cumulative volume in the particle size distribution is 50% by volume.

[0071] Furthermore, relative to 100% by weight of the silicon-carbon composite, the third-carbon material is present in an amount of 1% to 50% by weight, and the silicon particles are present in an amount of 30% to 70% by weight. The second-carbon material is present in an amount of 20% to 69% by weight. When the content of silicon particles, the third-carbon material, and the second-carbon material falls within the above ranges, the discharge capacity of the secondary battery is excellent and the capacity retention rate is improved.

[0072] The particle size of the silicon particles is 10 nm to 30 μm, for example, 10 nm to 1000 nm, or 20 nm to 150 nm. When the average particle size of the silicon particles falls within this range, it is possible to suppress or reduce volume expansion that occurs during charging and discharging, and to prevent disruption of electron transfer due to particle fragmentation during charging and discharging.

[0073] In the silicon-carbon composite, for example, the second carbonaceous material is crystalline carbon, and the third carbonaceous material is also amorphous carbon. That is, the silicon-carbon composite is a silicon-carbon composite including a core containing silicon particles and crystalline carbon and an amorphous carbon coating layer located on the surface of the core.

[0074] The silicon-carbon composite is, for example, also a silicon-carbon nanocomposite. The silicon-carbon nanocomposite means a composite in which one or more of silicon and carbon have a nano size of less than 1 μm. For example, the silicon-carbon nanocomposite is also a composite in which silicon nanoparticles and carbon nanoparticles are combined.

[0075] The silicon-containing compound may include, for example, silicon, a silicon alloy, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, or a combination thereof. The silicon-containing compound may include, for example, SiO x (0 < x < 2).

[0076] The silicon alloy includes silicon and elements of an alkali metal, an alkaline earth metal, a Group 13-16 element, a transition metal, a rare earth element, or a combination thereof. The elements are, for example, Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Ti, Ge, P, As, Sb, Bi, S, Se, Te, Po, or a combination thereof.

[0077] According to another embodiment, the silicon composite structure includes porous silicon secondary particles; and a first carbon flake disposed on the porous silicon secondary particles, the porous silicon secondary particles being an aggregate of a plurality of silicon composite primary particles, the silicon composite primary particles including silicon; silicon dioxide (SiO2) and / or silicon suboxide (SiO x, (0 < x < 2); and may include a second carbon flake disposed on the silicon dioxide (SiO2) and / or silicon suboxide.

[0078] The silicon composite structure includes porous silicon secondary particles containing aggregates of a plurality of silicon composite primary particles and a first carbon flake disposed on the porous silicon secondary particles. And the first carbon flake disposed on the porous silicon secondary particles can be arranged to cover at least one surface of the porous silicon secondary particles. The first carbon flake can be directly disposed on the porous silicon secondary particles. The first carbon flake can directly grow on the silicon suboxide of the porous silicon secondary particles. The first carbon flake can directly grow from the surface of the porous silicon secondary particles and be directly disposed on the surface of the porous silicon secondary particles. The first carbon flake can cover the surface of the porous silicon secondary particles entirely or partially. The coverage rate of the first carbon flake is, for example, 5 - 100%, 10 - 99%, 20 - 95%, or 40 - 90% based on the total surface area of the porous silicon secondary particles. The carbon of the first carbon flake exists on the surface of the porous silicon secondary particles and effectively buffers the volume change of the porous silicon secondary particles. The size of the porous silicon secondary particles is, for example, 1 - 20 μm, 2 - 18 μm, or 3 - 10 μm. The size of the first carbon flake is, for example, 1 - 200 nm, 5 - 150 nm, or 10 - 100 nm. Here, the size means the diameter or the major axis length.

[0079] The silicon composite primary particle is silicon; silicon, silicon suboxide (SiO disposed on at least one surface of the silicon x, (0 < x < 2); and includes a second carbon flake disposed on one surface of the silicon suboxide. The silicon is, for example, in the form of a plate, needle, sphere, or a combination thereof. The shape of the silicon is not limited, and for example, it can be spherical, nanowire, needle, rod, particle, nanotube, nanorod, wafer, and nanoribbon, or a combination thereof. The average size of the silicon is, for example, 10 nm to 1 μm, 10 nm to 500 nm, 20 to 150 nm, or 100 nm. When the silicon is spherical particles, the average size of the silicon is the average particle diameter, and when it is non-spherical particles, such as plate-like particles or needle-like particles, it can mean the major axis length, length, or thickness. The silicon suboxide (SiO x )(0 < x < 2) disposed on the silicon can be arranged to cover at least one surface of the silicon. The silicon suboxide can be directly disposed on the silicon. The silicon suboxide can cover the surface of the silicon entirely or partially. The coverage rate of the silicon suboxide is, for example, based on the total surface area of the silicon, for example, 1 to 100%, 5 to 99%, 10 to 95%, or 20 to 90%. The second carbon flake disposed on the silicon suboxide can be arranged to cover at least one surface of the silicon suboxide. The second carbon flake can be directly disposed on the silicon suboxide. The second carbon flake can grow directly from the surface of the silicon suboxide and be directly disposed on the surface of the silicon suboxide. The second carbon flake can, for example, cover the surface of the silicon suboxide entirely or partially. The coverage rate of the second carbon flake is, for example, based on the total surface area of the silicon suboxide, for example, 10 to 100%, 10 to 99%, 20 to 95%, or 40 to 90%. The carbon of the second carbon flake is present on the surface of the silicon and / or silicon suboxide and can effectively buffer the volume change of the silicon composite primary particles. The size of the second carbon flake is, for example, 1 to 200 nm, 5 to 150 nm, or 10 to 100 nm. Here, the size means the diameter or the major axis length.

[0080] The silicon composite structure includes porous silicon secondary particles and a second carbon flake arranged on the porous silicon secondary particles. The second carbon flake may be arranged to completely or partially cover the porous silicon secondary particles. For example, the second carbon flake may be arranged to completely or partially surround the porous silicon secondary particles. The porous silicon secondary particles include a first carbon flake arranged on the silicon composite primary particles. During volume expansion / contraction of the silicon composite structure, the silicon contained in the porous silicon secondary particles can maintain contact with the first carbon flake and / or the second carbon flake. Due to the pores in the porous secondary particles, they act as an internal buffer space during volume expansion / contraction of the silicon composite structure. Therefore, unlike conventional silicon-based anode active materials, the silicon composite structure can effectively accommodate volume changes during charging and discharging while suppressing an increase in internal resistance.

[0081] The porosity of silicon composite structures can be, for example, 60% or less, or 30% to 60%. In other embodiments, silicon composite structures can also be non-porous. Non-porous structures have porosity of, for example, 10% or less, or 5% or less. Non-porous structures can also have porosity of, for example, 0.01% to 5%, or 0%. Porosity can be measured by mercury adsorption (porosimetry) or nitrogen adsorption.

[0082] Silicon composite structures may have, for example, non-spherical morphologies. The degree of spherularity of silicon composite structures is, for example, 0.9 or less. The degree of spherularity of silicon composite structures is, for example, 0.7-0.9, 0.8-0.9, or 0.85-0.9. The degree of spherularity is, for example, 4πA / P 2 It is determined by (A being the area and P being the boundary line (perimeter)).

[0083] The silicon composite structure includes a first carbon flake and a second carbon flake. The first carbon flake and the second carbon flake can also be, for example, carbon flakes that are equal to each other. Any carbon-based material having a flake shape can be used as the first carbon flake and the second carbon flake. The first carbon flake and the second carbon flake can also be graphene, graphite, carbon fiber, graphitic carbon, graphene oxide, or mixtures thereof, independently of each other. The porous composite structure may include, for example, first graphene and second graphene as the first carbon flake and the second carbon flake. The first graphene and the second graphene can each have structures such as nanosheets, membranes (or films), or flakes. A nanosheet refers to a form that is irregularly formed on silicon suboxide or porous silicon secondary particles with a thickness of about 1000 nm or less, for example, 1 to 1000 nm. A film is a form of material that is continuously and uniformly formed on silicon suboxide or porous silicon secondary particles.

[0084] The silicon-containing structure may further include a carbon-based coating layer disposed on the silicon composite structure. The carbon-based coating layer can improve the physical stability of the silicon composite structure and more effectively prevent side reactions between silicon and electrolyte during charging and discharging. The carbon-based coating layer may include, for example, primary amorphous carbon. The carbon-based coating layer may include high-density primary amorphous carbon. Primary amorphous carbon may include, for example, pitch carbon, soft carbon, hard carbon, mesophase pitch carbide, calcined coke, carbon fibers, or mixtures thereof. The carbon-based coating layer may further include crystalline carbon. By further including crystalline carbon in the carbon-based coating layer, the buffering role against volume changes of the silicon composite structure can be performed more effectively. Crystalline carbon may also be, for example, natural graphite, artificial graphite, graphene, fullerene, carbon nanotubes, or mixtures thereof. The thickness of the carbon-based coating layer may also be, for example, 1 nm to 5000 nm, 10 nm to 2000 nm, or 5 nm to 2500 nm.

[0085] The silicon-containing structure may further include, for example, a second amorphous carbon disposed within the silicon composite structure. For example, the silicon composite structure may include porous silicon secondary particles, and the second amorphous carbon may be disposed within the pores of the porous silicon secondary particles. The second amorphous carbon may be disposed between a plurality of silicon composite primary particles constituting the porous silicon secondary particles. The silicon composite primary particles may be, for example, silicon; silicon dioxide (SiO2) and / or silicon suboxide (SiO2) disposed on the silicon. x, (0 < x < 2); and a second carbon flake disposed on silicon dioxide (SiO₂) and / or silicon suboxide; and may include a second amorphous carbon disposed on the second carbon flake. The silicon composite structure may have a dense structure with a non-porous structure by filling the internal pores thereof with dense second amorphous carbon. Since the silicon composite structure has such a non-porous structure, side reactions with the electrolyte during charge and discharge are further reduced, and the volume change of silicon can be more effectively alleviated. The second amorphous carbon may include, for example, pitch carbon, soft carbon, hard carbon, mesophase pitch carbide, calcined coke, carbon fiber, or a mixture thereof.

[0086] The mixing ratio of the total weight of the first carbon, which is the sum of the carbon of the first carbon flake and the carbon of the second carbon flake, and the second carbon, which is the carbon of the carbon-based coating layer, in the silicon composite structure is, for example, 30:1 to 1:3, 20:1 to 1:1, or 10:1 to 1:0.9. By having such a mixing ratio of the first carbon and the second carbon, a lithium battery having improved cycle characteristics can be provided. The mixing ratio of the first carbon and the second carbon can be confirmed through thermogravimetric analysis. The first carbon is related to a peak shown in the region of 700 to 750 °C, and the second carbon is related to a peak shown in the region of 600 to 650 °C. The thermogravimetric analysis is carried out, for example, at a heating rate of about 10 °C / min in an air atmosphere in the range of 25 to 1,000 °C. The first carbon is, for example, crystalline carbon, and the second carbon is, for example, amorphous carbon. The mixing ratio of the total weight of the carbon of the first carbon flake and the carbon of the second carbon flake and the total weight of the first amorphous carbon and the second amorphous carbon is also, for example, 1:99 to 99:1, 1:20 to 80:1, or 1:1 to 1:10.

[0087] The core is SiO as a silicon-containing negative electrode active material, which is a silicon-containing compound. x (0 < x < 2) may be included. SiO x (0 < x < 2) has an average particle size of, for example, 1 μm or more, 3 μm or more, or 5 μm or more. SiO x(0 < x < 2), the average particle size is, for example, 1 μm to 30 μm, 3 μm to 20 μm, or 5 μm to 15 μm. For example, the core may contain a silicon-containing compound SiO2.

[0088] The shell contains a composite including a first metal oxide and a first carbon-based material.

[0089] Since the first carbon-based material, such as graphene, has high electronic conductivity, the interfacial resistance between the dry anode active material and the electrolyte can be reduced. Therefore, even though a shell containing the first carbon-based material is introduced, an increase in the internal resistance of the lithium battery is suppressed or reduced.

[0090] Since the first carbon-based material contained in the shell is derived from a graphene matrix, it has a relatively low density and a high porosity compared to conventional carbon-based materials derived from graphite-based materials. The interplanar distance of the first carbon-based material contained in the shell of the dry anode active material is, for example, 3.38 Å or more, 3.45 Å or more, 3.50 Å or more, 3.60 Å or more, 3.80 Å or more, or 4.00 Å or more. The interplanar distance of the first carbon-based material contained in the shell of the dry anode active material is, for example, 3.38 to 4.0 Å, 3.38 to 3.8 Å, 3.38 to 3.6 Å, 3.38 to 3.5 Å, or 3.38 to 3.45 Å. In contrast, the interplanar distance of conventional carbon-based materials derived from graphite-based materials is, for example, 3.38 Å or less, or 3.35 to 3.38 Å. Since the first metal oxide has voltage resistance, it can prevent the core from deteriorating during charge and discharge at high voltage. The shell may contain, for example, one kind of the first metal oxide, or two or more different first metal oxides. As a result, the cycle characteristics of the lithium battery containing the above-described dry anode active material are improved, and volume change can be suppressed.

[0091] The shell may include, for example, a first carbon-based material, and the core may include, for example, a silicon-containing structure and / or silicon-containing compound as a silicon-containing anode active material. For example, the first carbon-based material may be compounded with the silicon-containing structure and / or silicon-containing compound through a mechanochemical reaction. The first carbon-based material may be chemically bonded with the silicon-containing structure and / or silicon-containing compound through chemical bonding. The core and shell are compounded by the chemical bonding of the first carbon-based material placed in the shell and the silicon-containing structure and / or silicon-containing compound placed in the core. Thus, the composite anode active material is distinguished from a simple physical mixture of the first carbon-based material and the silicon-containing structure and / or silicon-containing compound. The first metal oxide and carbon-based material contained in the shell may also be chemically bonded through chemical bonding (bound). Here, the chemical bond is, for example, a covalent bond or an ionic bond.

[0092] The composite includes a first carbon-based material. The first carbon-based material may, for example, have a branched structure, and one or more metal oxides selected from a first metal oxide and a second metal oxide may be distributed within the branched structure of the first carbon-based material. The branched structure of the first carbon-based material may, for example, include a plurality of first carbon-based material particles in contact with each other. The branched structure of the first carbon-based material can provide diverse conductive pathways. The first carbon-based material may also be, for example, graphene. Graphene may, for example, have a branched structure, and one or more metal oxides selected from a first metal oxide and a second metal oxide may be distributed within the branched structure of graphene. The branched structure of graphene may, for example, include a plurality of graphene particles in contact with each other. The branched structure of graphene can provide diverse conductive pathways.

[0093] The first carbon-based material, for example, has a spherical structure, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structure. The size of the spherical structure of the first carbon-based material is also 50 nm to 300 nm. There may be multiple first carbon-based materials having a spherical structure. The presence of a spherical structure in the first carbon-based material allows the composite to have a robust structure. The first carbon-based material is, for example, graphene. Graphene, for example, has a spherical structure, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structure. The size of the spherical structure of graphene is also 50 nm to 300 nm. There may be multiple graphenes having a spherical structure. The presence of a spherical structure in graphene allows the composite to have a robust structure.

[0094] The first carbon-based material, for example, has a spiral structure in which multiple spherical structures are linked, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structures of the spiral structure. The size of the spiral structure of the first carbon-based material is 500 nm to 100 μm. The presence of a spiral structure in the first carbon-based material allows the composite to have a robust structure. The first carbon-based material is, for example, graphene. The graphene, for example, has a spiral structure in which multiple spherical structures are linked, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structures of the spiral structure. The size of the spiral structure of the graphene is 500 nm to 100 μm. The presence of a spiral structure in graphene allows the composite to have a robust structure.

[0095] The first carbon-based material, for example, has a cluster structure in which multiple spherical structures are aggregated, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structures of the cluster structure. The size of the cluster structure of the first carbon-based material is also 0.5 mm to 10 cm. The presence of a cluster structure in the first carbon-based material allows the composite to have a robust structure. The first carbon-based material is, for example, graphene. Graphene, for example, has a cluster structure in which multiple spherical structures are aggregated, and one or more metal oxides selected from the first and second metal oxides may be distributed within the spherical structures of the cluster structure. The size of the cluster structure of graphene is also 0.5 mm to 10 cm. The presence of a cluster structure in graphene allows the composite to have a robust structure.

[0096] The composite is, for example, a faceted-ball structure, in which one or more selected metal oxides from a first metal oxide and a second metal oxide may be distributed inside or on the surface of the structure. Because the composite is such a faceted-ball structure, it can be easily coated onto the irregular surface of the core.

[0097] The composite is, for example, a planar structure, in which one or more selected metal oxides from the first and second metal oxides may be distributed inside or on the surface of the planar structure. Because the composite is such a two-dimensional planar structure, it can be easily coated onto the irregular surface of the core.

[0098] The first carbon-based material extends over a distance of 10 nm or less in the first metal oxide and may contain at least 1 to 20 layers of the first carbon-based material. For example, by stacking multiple layers of the first carbon-based material, a first carbon-based material having a total thickness of 12 nm or less can be arranged on the first metal oxide. For example, the total thickness of the carbon-based material can also be 0.6 nm to 12 nm. The first carbon-based material is, for example, graphene. Graphene extends over a distance of 10 nm or less in the first metal oxide and may contain at least 1 to 20 graphene layers. For example, by stacking multiple graphene layers, graphene having a total thickness of 12 nm or less can be arranged on the first metal oxide. For example, the total thickness of the graphene can also be 0.6 nm to 12 nm.

[0099] The shell may further contain a second-carbon material, which is fibrous carbon. The second-carbon material may contain fibrous carbon.

[0100] The inclusion of a second-carbon material, in which the shell is fibrous carbon, further lengthens the conducting path of the anode active material. The second-carbon material can reduce the internal resistance of the anode containing the anode active material by forming a three-dimensional conductive network between multiple composite anode active materials. The fixation of fibrous carbon on the anode active material can form a uniform and stable three-dimensional conductive network between multiple anode active materials. Therefore, the high-efficiency performance of lithium batteries containing anode active materials containing second-carbon material can be improved.

[0101] The aspect ratio of the second carbon-based material is 10 or greater, for example, 10-100,000, 10-80,000, 10-50,000, 10-10,000, 10-5000, 10-1000, 10-500, 10-1000, or 10-100. The aspect ratio of the second carbon-based material is, for example, the ratio of the length of the major axis passing through the center of the second carbon-based material, i.e., the length of the second carbon-based material, to the length of the minor axis perpendicular to the major axis, i.e., the diameter of the second carbon-based material.

[0102] The diameter of the second carbon-based material can be, for example, 1 nm to 50 nm, 1 nm to 30 nm, or 1 nm to 10 nm. When the diameter of the second carbon-based material is within the above range, the absolute number of strands per unit volume decreases, allowing for uniform dispersion without reducing the effect of reducing internal resistance.

[0103] The length of the second carbon-based material can be, for example, 100nm to 1000μm, 100nm to 500μm, 100nm to 100μm, 100nm to 50μm, 100nm to 10μm, 100nm to 5μm, 100nm to 2μm, 100nm to 1μm, 100nm to 500nm, or 100nm to 300nm. The length of the second carbon-based material can also be, for example, 500nm to 1000μm, 500nm to 500μm, 500nm to 100μm, 500nm to 50μm, 500nm to 10μm, 500nm to 5μm, or 500nm to 2μm. When the length of the second carbon-based material is within the above range, it can provide an effective conductive path without reducing the internal resistance of the electrode.

[0104] Secondary carbon-based materials may include, for example, carbon nanofibers, carbon nanotubes, or combinations thereof.

[0105] Carbon nanotubes may include, for example, primary carbon nanotube structures, secondary carbon nanotube structures formed by the aggregation of multiple primary carbon nanotube particles, or combinations thereof.

[0106] A primary carbon nanotube structure is a single carbon nanotube unit.

[0107] Primary carbon nanotube structures may include, for example, single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), and multi-walled carbon nanotubes (MWCNTs), or combinations thereof. The diameter of the primary carbon nanotube structures may be, for example, 1 nm to 20 nm, 1 nm to 15 nm, or 2 nm to 10 nm. The length of the primary carbon nanotube structures may be, for example, 100 nm to 2 μm, 100 nm to 1 μm, 100 nm to 500 nm, 100 nm to 400 nm, 100 nm to 300 nm, or 200 nm to 300 nm. The diameter and length of the primary carbon nanotube structures may be measured by scanning electron microscopy (SEM) imaging or laser diffraction.

[0108] A carbon nanotube secondary structure is a structure formed by assembling carbon nanotube primary structures so that they form bundles or tufts, either entirely or partially. Carbon nanotube secondary structures may include, for example, bundle-type carbon nanotubes, rope-type carbon nanotubes, or combinations thereof. The diameter of a carbon nanotube secondary structure is, for example, 2 nm or more, or 3 nm or more. The diameter of a carbon nanotube secondary structure is, for example, 50 nm or less, 30 nm or less, or 10 nm or less. The diameter of a carbon nanotube secondary structure is, for example, 50 nm or less, 30 nm or less, or 10 nm or less. The diameter of a carbon nanotube secondary structure is also, for example, 2 nm to 50 nm, 2 nm to 30 nm, or 2 nm to 20 nm. The lengths of the carbon nanotube secondary structures can be, for example, 500 nm to 1000 μm, 500 nm to 500 μm, 500 nm to 200 μm, 500 nm to 100 μm, or 500 nm to 50 μm. The diameter and length of the carbon nanotube secondary structures can be measured by scanning electron microscopy (SEM) imaging, optical microscopy, or laser diffraction. The carbon nanotube secondary structures can be used, for example, to produce dry anode active materials after being dispersed in a solvent to convert them into carbon nanotube primary structures.

[0109] The content of the second carbon-based material is, for example, 0.1 wt% to 50 wt%, 1 wt% to 40 wt%, or 5 wt% to 30 wt% relative to the total weight of the first and second carbon-based materials. By including such ranges of first and second carbon-based materials in the dry anode active material, conduction paths can be more effectively secured within the dry composite anode active material, further reducing the internal resistance of the dry anode active material. As a result, the cycle characteristics of lithium batteries containing the dry anode active material can be further improved. The content of the second carbon-based material is, for example, 0.001 wt% to 5 wt%, 0.01 wt% to 3 wt%, or 0.01 wt% to 1 wt% relative to the total weight of the dry anode active material. By including a second-carbon material in such a range in the dry anode active material, conduction paths can be established within the composite anode active material, further reducing the internal resistance of the dry anode active material. As a result, the cycle characteristics of lithium batteries containing the dry anode active material can be further improved.

[0110] The specific surface area of ​​the dry anode active material is, for example, 1 m². 2 / g~100m 2 / g, 1m 2 / g~50m 2 / g, or 1m 2 / g~30m 2 The specific surface area of ​​the composite anode active material can further improve the cycle characteristics of lithium batteries employing such a composite anode active material. The average particle size (D50) of the composite anode active material is, for example, 1 μm to 30 μm, 3 μm to 20 μm, or 5 μm to 15 μm. The particle size (D10) of the composite anode active material is, for example, 0.1 μm to 10 μm, 0.5 μm to 10 μm, or 1 μm to 10 μm. The particle size (D90) of the composite anode active material is, for example, 10 μm to 50 μm, 10 μm to 30 μm, or 10 μm to 25 μm. The average particle size (D50), particle size (D10), and / or particle size (D90) of the composite anode active material can further improve the cycle characteristics of lithium batteries employing such a dry anode.

[0111] The content of the dry conductive material in the dry anode film is, for example, 0.1-5 wt%, 0.5-5 wt%, or 1-5 wt% relative to the total weight of the dry anode film. The inclusion of such a range of dry conductive material in the dry anode film improves its conductivity, which in turn improves the cycle characteristics of lithium batteries containing such dry anode films.

[0112] A dry anode film is, for example, a self-standing film. A dry anode film can, for example, maintain its film form without a support. Therefore, a dry anode film can be prepared as a separate self-standing film and then placed on an electrode current collector. Since a dry anode film is manufactured by a dry process, it does not contain intentionally added process solvents. For example, it does not contain residual processing solvents. While unintended trace amounts of solvent may remain in a dry anode film, such solvents are not intentionally added process solvents. Therefore, a dry anode film is distinguished from a wet electrode film, which is manufactured by mixing the components with a process solvent and then removing some or all of the process solvent by drying.

[0113] In one embodiment, a dry anode film comprises a first dry anode film containing a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof as the core of the dry composite anode active material, and the second dry anode film contains a carbon-based material as the core of the dry composite anode active material, wherein the binder content of the first dry anode film is the same as or greater than the binder content of the second dry anode film, respectively. In some embodiments, the binder content of the first dry anode film is the same as or greater than the binder content of the second dry anode film. In some embodiments, the amount of composite in the first dry anode film is the same as or greater than the composite content of the second dry anode film.

[0114] The second dry anode film may further contain a conductive material. The conductive material may be a composite (GB), Denka Black, Summer Black, Super P, carbon nanotubes, activated carbon, carbon molecular sieves, graphene, carbon black, graphite nanoparticles, natural graphite, artificial graphite, acetylene black, Ketjenblack, carbon fibers, carbon nanotubes; metal powders such as copper, nickel, aluminum, and silver, or metal fibers or metal tubes; conductive polymers such as polyphenylene derivatives. Here, the composite is the same as the composite containing one or more first metal oxides and first carbon-based materials that constitute the shell of the composite anode active material, so the explanation related to it will be omitted.

[0115] The dry anode film includes a first dry anode film disposed adjacent to the anode current collector and a second dry anode film disposed on the first dry anode film, wherein the first dry anode film includes a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof as the core of the dry composite anode active material, and the second dry anode film includes a mixture of a carbon-based compound and a silicon-based active material; a composite of a carbon-based compound and a silicon-based active material; or a combination thereof as the core of the dry anode active material. Including composites, the content of the composite (GB) and binder in the first dry anode film is the same as or greater than the content of the composite and binder in the second dry anode film, and the content of the mixture of carbon-based material and silicon-based active material; the composite of carbon-based material and silicon-based active material; or combination thereof in the first dry anode film is the same as or greater than the content of the mixture of carbon-based material and silicon-based active material; the composite of carbon-based material and silicon-based active material; or combination thereof in the second dry anode film. In some embodiments, the amount of binder in the first dry anode film is the same as or greater than the amount of composite material (GB) in the second dry anode film. The dry anode film has the same or greater content of composite material (GB) in the second dry anode film. In some embodiments, the content of carbon-based material in the first dry anode film is the same as the content of carbon-based material in the second dry anode film, and the content of silicon is greater than or equal to that of carbon-based material in the second dry anode film. The content of silicon-based active material in the first dry anode film is the same as, or greater than, the content of silicon-based active material in the second dry anode film.

[0116] The first dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry composite anode active material, the silicon-based active material includes a silicon composite structure, and the second dry anode film includes a carbon-based material as the core of the dry composite anode active material, and the binder and composite content of the first dry anode film are the same as or greater than the binder and composite content of the second dry anode film, respectively.

[0117] The dry anode film includes a first dry anode film disposed adjacent to the anode current collector and a second dry anode film disposed on the first dry anode film. The first dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry composite anode active material, and the second dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry anode active material. Here, the silicon-based active material of the first dry anode film and the second dry anode film includes a silicon composite structure. The binder content of the first dry anode film is the same as or greater than the binder content of the second dry anode film, and the composite (GB) content of the first dry anode film is the same as or greater than the composite content of the second dry anode film.

[0118] In the first dry anode film, the content of carbon-based material is the same as or greater than the content of carbon-based material in the second dry anode film. Furthermore, in the first dry anode film, the content of silicon-based active material is the same as or greater than the content of silicon-based active material in the second dry anode film.

[0119] Referring to the attached drawings, the structure of a dry anode-separator subassembly employing a dry anode film according to one embodiment will be described.

[0120] Referring to Figure 3A, the dry negative electrode-separator subassembly 200 has a structure in which a first dry negative electrode film 20a is laminated on a negative electrode current collector 20, a second dry negative electrode film 20b is laminated on top of the first dry negative electrode film 20a, and a separator 4 is laminated on top of that.

[0121] The dry negative electrode separator subassembly 200 shown in Figure 3B differs from the one in Figure 3A only in that an intermediate layer 30 is placed between the negative electrode current collector 20 and the first dry negative electrode film 20a.

[0122] Figures 4A to 4C show the laminated structure of a dry anode according to one embodiment, and specifically indicate the compositions of the first dry anode and the second dry anode.

[0123] According to one embodiment, as shown in Figure 4A, the first dry anode film 20a includes a composite anode active material in which a composite (GB1)-containing shell is coated on graphite, which is a carbon-based material that is the first anode active material, a silicon composite structure (SCN) which is the second anode active material, and polytetrafluoroethylene (PTFE1) which is a dry binder. The second dry anode film 20b includes a composite anode active material in which a composite (GB2)-containing shell is coated on graphite, which is the first anode active material, a silicon composite structure (SCN) which is the second anode active material, and polytetrafluoroethylene (PTFE2) which is a dry binder.

[0124] The silicon composite structure is a silicon-carbon composite containing silicon particles and a first carbon-based material, a silicon-carbon composite containing a core in which silicon particles and a second carbon-based material are mixed and a third carbon-based material surrounding the core, or a combination thereof.

[0125] The PTFE1 and GB1 content of the first dry anode film 20a is adjusted to be the same as, or significantly greater than, the PTFE2 and GB2 content of the second dry anode film 20b (PTFE1 ≥ PTFE2, GB1 ≥ GB2). When the content is within this range, it is possible to effectively prevent the dry anode film from peeling off from the anode current collector and induce minimal lithium dendrite growth in the direction away from the anode current collector.

[0126] The mixed weight ratio of PTFE1 to PTFE2 is not restricted, but is typically 10:1 to 1.1:1, 9.5:1 to 1.3:1, 9:1 to 1.5:1, 9:1 to 1.5:1, 6:1 to 1.5:1, 5:1 to 1.8:1, or 4:1 to 2:1.

[0127] The mixed weight ratio of GB1 to GB2 is not restricted, but is limited to 10:1 to 1.1:1, 9.5:1 to 1.3:1, 9:1 to 1.5:1, 9:1 to 1.5:1, 6:1 to 1.5:1, 5:1 to 1.8:1, or 4:1 to 2:1.

[0128] In the first dry anode film and the second dry anode film, the content of the silicon composite structure is 5 to 20 parts by weight, 11 to 18 parts by weight, or 12 to 15 parts by weight, based on a total content of 100 parts by weight of graphite and silicon composite structure.

[0129] According to another embodiment, as shown in Figure 4B, the first dry anode film 20a includes a composite anode active material in which a composite (GB1)-containing shell is coated on graphite, which is the first anode active material, a silicon composite structure, which is the second anode active material, and polytetrafluoroethylene (PTFE1), which is the dry binder. The second dry anode film 20a includes a composite anode active material in which a composite (GB2)-containing shell is coated on graphite, which is the first anode active material, a silicon composite structure, which is the second anode active material, and polytetrafluoroethylene (PTFE2), which is the dry binder.

[0130] The SCN1 content of the first dry anode film is adjusted to be significantly larger than the SCN2 content of the second dry anode film. When the SCN1 content is adjusted to be significantly larger than the SCN2 content in this way, the PTFE1 and GB1 content of the first dry anode film are the same as, or significantly larger than, the PTFE2 and GB2 content of the second dry anode film, respectively (SCN1≧SCN2, PTFE1≧PTFE2, GB1≧GB2). Within this range, volume expansion of the dry anode film is suppressed, and lithium dendrite growth can be induced to be small on the anode film furthest from the current collector.

[0131] The mixed weight ratio of SCN1 content in the first dry anode film and SCN2 content in the second dry anode film is not limited, but is 10:1 to 1.1:1, 9.5:1 to 1.3:1, 9:1 to 1.5:1, 9:1 to 1.5:1, 6:1 to 1.5:1, 5:1 to 1.8:1, or 4:1 to 2:1.

[0132] When the silicon content of the first dry anode film is greater than that of the second dry anode film, the electrode expansion rate is reduced, dendrite formation is reduced during rapid charging, electrolyte immersion characteristics are improved, electrode detachment is reduced, and higher electrode stability can be ensured with less binder. Furthermore, if the PTFE1 and GB1 content of the first dry anode film is the same as, or significantly greater than, the PTFE2 and GB2 content of the second dry anode film, respectively, peeling of the dry anode film from the anode current collector can be efficiently prevented, and lithium dendrite growth can be induced to be smaller in the direction away from the anode current collector.

[0133] In yet another embodiment, as shown in Figure 4C, the second dry negative electrode film 20b, positioned further away from the negative electrode current collector 20, contains a first composite negative electrode active material comprising a graphite core / composite (GB1) shell and a binder PTFE1 as the negative electrode active material, while the first dry negative electrode film 20a, positioned adjacent to the negative electrode current collector 20, utilizes a first composite negative electrode active material in which a composite (GB1)-containing shell is coated on graphite, a second composite negative electrode active material comprising a silicon composite structure (SCN) core / composite (GB2) shell and a binder PTFE2 as the dry composite negative electrode active material.

[0134] The total content of graphite-silicon composite structures (SCNs) in the first dry anode film can be adjusted to a greater extent than the graphite content in the second dry anode film.

[0135] The mixed weight ratio of the total content of graphite-silicon composite structures (SCNs) in the first dry anode film to the graphite content in the second dry anode film is not limited, but is 10:1 to 1.1:1, 9.5:1 to 1.3:1, 9:1 to 1.5:1, 9:1 to 1.5:1, 6:1 to 1.5:1, 5:1 to 1.8:1, or 4:1 to 2:1.

[0136] For example, in the first composite negative electrode active material, the content of composite (GB1) can be controlled to be significantly larger than that of composite (GB2), and the content of the binder PTFE1 can be the same as or significantly larger than that of the binder PTFE2 (PTFE1 ≥ PTFE2, GB1 ≥ GB2). By forming such a structure, volume expansion can be controlled, and on the side far from the current collector, a structure can be formed that induces small lithium dendrite growth.

[0137] In Figures 4B and 4C, the mixed weight ratios of PTFE1 and PTFE2, and GB1 and GB2, are the same as those described in Figure 4A.

[0138] The first and second dry anode films in Figures 4A to 4C may further contain conductive materials. For example, the second dry anode film in Figure 4C contains a first composite anode active material including a graphite core / composite (GB1) shell as the anode active material and PTFE1 as a binder, but the second dry anode film may further contain conductive materials. As the conductive material, composites (GB) can be used. Here, the composite is the same as the composite containing one or more first metal oxides and a first carbon-based material that constitute the shell of the composite anode active material, so the explanation related to it will be omitted.

[0139] In a dry anode including the dry anode film described above, the thicknesses of the first dry anode film and the second dry anode film can be formed in a ratio of 1:3 to 3:1, 1:2 to 2:1, or 1:1.

[0140] According to one embodiment, the dry negative electrode film has a multilayer structure of two or more layers, two to five layers, or two to three layers, and is capable of forming a thick film.

[0141] As used herein, the term "solvent-free" refers to a component that eliminates any amount of residual processing solvent necessary for proper operation. According to one embodiment, the dry anode film is a self-standing film and the dry anode film is free of residual processing solvent, for example, solvent-free.

[0142] The tensile strength of the dry anode film according to one embodiment is, for example, 450 kPa or more, 500 kPa or more, 700 kPa or more, or 1000 kPa or more at 25°C. This tensile strength is relevant before rolling. The tensile strength of the dry anode film before rolling is also, for example, 500 kPa to 5000 kPa, 600 kPa to 5000 kPa, 700 kPa to 5000 kPa, or 800 kPa to 5000 kPa at 25°C.

[0143] The tensile strength of the dry anode film after rolling at 25°C is 1000kPa or more, 1050kPa or more, 1200kPa or more, or 1500kPa or more. The tensile strength of the dry anode film after rolling at 25°C is also, for example, 1000kPa to 5000kPa, 1050kPa to 5000kPa, 1090kPa to 5000kPa, 1200kPa to 5000kPa, or 1800kPa to 5000kPa. Having a tensile strength within the above ranges of the dry anode film can improve its structural stability. Therefore, the dry anode film can maintain a stable three-dimensional conductive network during the charge-discharge process, improving the reversibility of the electrode reaction. Having a high tensile strength within such a range of the dry anode film can improve its mechanical strength. The improved mechanical strength of the dry negative electrode film can suppress or reduce localized degradation due to volume changes during charging and discharging of the electrode equipped with the dry negative electrode film and the lithium battery containing it. As a result, the cycle characteristics of the lithium battery can be improved.

[0144] The dry anode film provides improved cycle characteristics and reduced volume change, including the dry anode active material described above.

[0145] A method for manufacturing a dry anode includes, for example, the steps of: preparing a dry mixture by dry mixing a dry composite anode active material and a dry binder; providing a anode current collector; placing an intermediate layer on one surface of the anode current collector; and placing the dry mixture on the intermediate layer and rolling it to obtain a dry anode film, thereby manufacturing a anode in which a anode active material layer is placed on one surface of the anode current collector.

[0146] First, the composite negative electrode active material and the dry binder are dry-mixed to prepare a dry mixture.

[0147] The dry mixture may further contain a dry conductive material during its production.

[0148] Dry mixing means mixing without the process solvent. The process solvent is, for example, the solvent used in the manufacture of the electrode slurry. The process solvent is, for example, water, NMP, etc., but is not limited to these, as long as it is a process solvent used in the manufacture of the electrode slurry. Dry mixing can be carried out using a stirrer at a temperature of, for example, 25 to 65°C. Dry mixing can be carried out using a stirrer at a rotational speed of, for example, 10 to 10,000 rpm or 100 to 10,000 rpm. Dry mixing can be carried out using a stirrer for, for example, 1 to 200 minutes or 1 to 150 minutes. The composite anode active material is a dry composite anode active material.

[0149] Dry mixing may be performed, for example, one or more times. First, the dry composite anode active material and the dry binder are primary dry-mixed to prepare the first mixture. During the preparation of the first mixture, the dry conductive material is further added. Primary dry mixing may be performed, for example, at a temperature of 25-65°C, at a rotation speed of 2000 rpm or less, or 500-2000 rpm, for 15 minutes or less, for example, 5-15 minutes. Primary dry mixing may ensure that the dry composite anode active material and the dry binder are uniformly mixed. Next, the dry composite anode active material and the dry binder may be secondary dry-mixed to prepare the second mixture. Secondary dry mixing may be performed, for example, at a temperature of 25-65°C, or at a rotation speed of 4000 rpm or more, or 4000-9000 rpm, for 10 minutes or more, or 10-60 minutes. A dry mixture containing a fibrillated dry binder is obtained by secondary dry mixing.

[0150] The agitator is, for example, a kneader. The agitator includes, for example, a chamber; one or more rotating shafts located inside the chamber and rotating; and blades rotatably coupled to the rotating shafts and positioned longitudinally along the rotating shafts. The blades are, for example, one or more selected from ribbon blades, sigma blades, jet (Z) blades, dispersion blades, and screw blades. The inclusion of blades allows for the effective mixing of dry anode composite active material, dry conductive material, and dry binder without solvent to produce a mixture in a dough-like form.

[0151] The manufactured dry mixture can be fed into an extruder and extruded into a sheet. The extrusion pressure is, for example, 4 MPa to 100 MPa or 10 MPa to 90 MPa. The resulting sheet-like extruded material is a dry anode film, which serves as the sheet for the anode active material layer. By repeating this process, a dry anode film with a multilayer structure can be easily manufactured.

[0152] Dry conductive materials include, but are not limited to, carbon black, graphite nanoparticles, natural graphite, artificial graphite, acetylene black, Ketjenblack, carbon fibers, carbon nanotubes, metal powders such as copper, nickel, aluminum, and silver, or metal fibers or tubes, and conductive polymers such as polyphenylene derivatives. Any conductive material usable in the relevant technical field is acceptable. The conductive material is, for example, a carbon-based conductive material. A dry conductive material is a conductive material that has not come into contact with the process solvent.

[0153] According to one embodiment, the dry binder includes a fluorine-based binder.

[0154] Dry binders used include vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polytetrafluoroethylene (PTFE), mixtures of the aforementioned polymers, and styrene-butadiene rubber polymers, but are not limited to these; any binder used in the relevant technical field can be used. An example of a dry binder is polytetrafluoroethylene (PTFE). The term "dry binder" refers to a binder that has not come into contact with the process solvent.

[0155] In some embodiments, the dry binder is also a fibrillized binder. As used herein, the term “fibrillated” refers to the process of converting the fibers of a material into smaller individual units of material (e.g., grinding or pulverizing). In one embodiment, the dry binder may have a glass transition temperature (Tg) of about 15°C to 100°C.

[0156] A plasticizer or pore-forming agent can be further added to the dry mixture to form pores within the negative electrode active material layer.

[0157] The content of the dry composite negative electrode active material, dry conductive material, and dry binder used in the negative electrode active material layer is within the same range as when manufacturing a wet negative electrode. Then, a negative electrode current collector is provided.

[0158] Although not shown in the drawings, the negative electrode current collector may include, for example, a base film and a metal layer disposed on one or both sides of the base film. The base film may include, for example, a polymer. The polymer may also be, for example, a thermoplastic polymer. The polymer may include, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI), or a combination thereof. The inclusion of a thermoplastic polymer in the base film allows the base film to liquefy when a short circuit occurs, thereby suppressing a rapid increase in current. The base film may also be, for example, an insulator. The metal layer may include, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), or alloys thereof.

[0159] The metal layer can act as an electrochemical fuse, disconnecting in the event of overcurrent to prevent short circuits. The limit current and maximum current can be adjusted by adjusting the thickness of the metal layer. The metal layer is plated or deposited onto the base film. Reducing the thickness of the metal layer decreases the limit current and / or maximum current of the negative electrode current collectors 521b and 522b, which can improve the stability of the lithium battery during short circuits. Lead tabs may be added to the metal layer for external connection. The lead tabs can be welded to the metal layer or the metal layer / base film laminate by ultrasonic welding, laser welding, spot welding, etc. During welding, the base film and / or metal layer may melt while the metal layer is electrically connected to the lead tab. To further strengthen the weld between the metal layer and the lead tab, a metal chip may be added between the metal layer and the lead tab. The metal chip is also a thin piece of the same material as the metal layer. The metal chips can be, for example, metal foil, metal mesh, etc. The metal chips can also be, for example, aluminum foil, copper foil, SUS foil, etc. After placing the metal chips on the metal layer, the lead tabs can be welded to the metal chip / metal layer laminate or the metal chip / metal layer / base film laminate by welding them to the metal chips. During welding, the base film, metal layer, and / or metal chips may melt, while the metal layer or metal layer / metal chip laminate is electrically connected to the lead tabs. Metal chips and / or lead tabs may be added to a portion of the metal layer. The thickness of the base film can be, for example, 1-50 μm, 1.5-50 μm, 1.5-40 μm, or 1-30 μm. Having the base film in such a thickness range can further effectively reduce the weight of the electrode assembly. The melting point of the base film can be, for example, 100°C-300°C, 100°C-250°C, or 100°C-200°C. The base film having a melting point within such a range allows it to melt during the welding process of the lead tabs, making it easily bonded to the lead tabs.Surface treatments such as corona treatment may be performed on the base film to improve the adhesion between the base film and the metal layer. The thickness of the metal layer can be, for example, 0.01-3 μm, 0.1-3 μm, 0.1-2 μm, or 0.1 μm. Having the metal layer in such a thickness range can ensure the stability of the electrode assembly while maintaining conductivity. The thickness of the metal piece can be, for example, 2-10 μm, 2-7 μm, or 4-6 μm. Having the metal piece in such a thickness range can further facilitate the connection between the metal layer and the lead tab. Having such a structure in the negative electrode current collector can reduce the weight of the electrode and, as a result, improve the energy density.

[0160] The negative electrode current collector is, for example, aluminum foil.

[0161] Next, an intermediate layer is placed on at least one surface of the negative electrode current collector. The intermediate layer may include a carbon-based conductive material and a binder. The intermediate layer may be omitted.

[0162] Carbon-based conductive materials may be fibrous carbon-based materials, particulate carbon-based materials, or combinations thereof. The aspect ratios of the fibrous carbon-based materials and particulate carbon-based materials are independently 10 or greater, for example, approximately 10-100,000, approximately 10-80,000, approximately 10-50,000, approximately 10-100,000, approximately 10,000, approximately 10-5,000, approximately 10-1,000, approximately 10-500, approximately 10-100, or approximately 10-50.

[0163] Next, a dry negative electrode film, which is a sheet for the negative electrode active material layer prepared on the intermediate layer, is placed and rolled to manufacture a negative electrode in which the negative electrode active material layer is placed on one surface of the negative electrode current collector. An intermediate layer is placed between the negative electrode current collector and the negative electrode active material layer.

[0164] Rolling can be done using methods such as roll presses and plate presses, but is not necessarily limited to these. The pressure during rolling is, for example, 0.1 ton / cm². 2 ~10.0 ton / cm 2However, it is not limited to such a range. If the rolling pressure increases excessively, it can cause cracks in the negative electrode current collector. If the rolling pressure is too low, the bonding force between the negative electrode current collector and the negative electrode active material layer may decrease.

[0165] Furthermore, lithium batteries according to other embodiments employ a negative electrode that includes the dry negative electrode film described above.

[0166] By employing the aforementioned negative electrode, the lithium battery offers improved interfacial resistance, cycle characteristics, and reduced volume change.

[0167] Lithium batteries are manufactured, for example, by the exemplary methods described below, but are not necessarily limited to such methods and may be adjusted according to the required conditions.

[0168] First, a dry anode is manufactured using the anode manufacturing method described above.

[0169] Next, a positive electrode active material composition is provided, which is a mixture of positive electrode active material, conductive material, binder, and solvent. The positive electrode plate is manufactured by directly coating and drying the positive electrode active material composition onto a positive electrode current collector. In another embodiment, the positive electrode active material composition may be cast onto a separate support, and then the film peeled off the support may be laminated onto an aluminum current collector to manufacture a positive electrode plate.

[0170] The positive electrode active material can be any lithium-containing metal oxide that is commonly used in the industry, without limitation. For example, the positive electrode active material may be one or more composite oxides of lithium and metals selected from cobalt, manganese, nickel, and combinations thereof. The positive electrode active material may include, but is not limited to, one or more selected from the group consisting of lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium iron phosphate, and lithium manganese oxide; any of these can be used as a positive electrode active material for lithium batteries in the art.

[0171] The positive electrode active material is, for example, Li a A 1-b B b D2 (In the above formula, 0.90 ≤ a ≤ 1.8 and 0 ≤ b ≤ 0.5); Li a E 1-b B b O 2-c D c (In the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, and 0 ≤ c ≤ 0.05); LiE 2-b B b O 4-c D c (In the above formula, 0 ≤ b ≤ 0.5 and 0 ≤ c ≤ 0.05); Li a Ni 1-b-c Co b B c D α (In the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, and 0 < α ≤ 2); Li a Ni 1-b-c Co b B c O 2-α F α (In the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, and 0 < α < 2); Li a Ni 1-b-c Co b B c O 2-α F2(In the above equation, 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2);Li a Ni 1-b-c Mn b B c D α (In the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, and 0 < α ≤ 2); Li a Ni 1-b-c Mn b B c O 2-α F α (In the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, and 0 < α < 2); Li a Ni 1-b-c Mn b Bc O 2-α F2 (in the formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni b E c G d O2 (in the formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0.001 ≤ d ≤ 0.1); Li a Ni b Co c Mn d GeO2 (in the formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, 0.001 ≤ e ≤ 0.1); Li a NiG b O2 (in the formula, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a CoG b O2 (in the formula, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a MnG b O2 (in the formula, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn2G b O4 (in the formula, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); QO2; QS2; LiQS2; V2O5; LiV2O5; LiIO2; LiNiVO4; Li (3-f) J₂(PO₄)₃ (0 ≤ f ≤ 2); Li (3-f) It may contain a compound represented by any one of the chemical formulas of Fe₂(PO₄)₃ (0 ≤ f ≤ 2); and LiFePO₄.

[0172] In the chemical formulas above, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, or a combination thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; F is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; Q is Ti, Mo, Mn, or a combination thereof; I is Cr, V, Fe, Sc, Y, or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0173] It is also possible to use compounds with a coating layer attached to their surface, and mixtures of the above-mentioned compounds and compounds with a coating layer attached are also possible. The coating layer attached to the surface of the above-mentioned compounds includes, for example, coating element compounds of oxide, hydroxide, oxyhydroxy, oxycarbonate, or hydroxycarbonate of the coating element. The compounds forming such a coating layer are amorphous or crystalline. The coating elements included in the coating layer are Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. The method for forming the coating layer is selected within a range that does not adversely affect the physical properties of the positive electrode active material. The coating method is, for example, spray coating or immersion method. The specific coating method is well understood by those skilled in the art, so a detailed explanation is omitted.

[0174] Examples of positive electrode active materials include LiNiO2, LiCoO2, and LiMn. x O 2x (x=1, 2), LiNi 1-x Mn x O2(0 <x<1)、LiNi 1-x-y Co x Mn y O 2((0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5), LiFeO2, V2O5, TiS, MoS, etc. may be used.

[0175] The positive electrode active material is, for example, Li a Ni x Co y M z O 2-b A b (1.0 ≦ a ≦ 1.2, 0 ≦ b ≦ 0.2, 0.8 ≦ x < 1, 0 ≦ y ≦ 0.3, 0 < z ≦ 0.3, x + y + z = 1, M is one or more selected from the group consisting of manganese (Mn), niobium (Nb), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al) and boron (B), A is F, S, Cl, Br or a combination thereof), LiNi x Co y Mn z O2(0.8 ≦ x ≦ 0.95, 0 < y ≦ 0.2, 0 < z ≦ 0.2 and x + y + z = 1), LiNi x Co y Al z O2(0.8 ≦ x ≦ 0.95, 0 ≦ y ≦ 0.2, 0 < z ≦ 0.2, x + y + z = 1), LiNi x Co y Al v Mn <​​​​​​​​​​​​(1.0 ≤ a ≤ 1.2, 0 ≤ b ≤ 0.2, 0 < x ≤ 0.3, 0.5 ≤ y < 1, 0 < z ≤ 0.3, and x + y + z = 1, M' is cobalt (Co), niobium (Nb), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), boron (B) or a combination thereof, A is F, S, Cl, Br or a combination thereof, etc. can be used.)

[0176] For the conductive material, binder and solvent in the positive electrode active material composition, the same ones as those in the case of the negative electrode active material composition can be used. On the other hand, it is also possible to further add a plasticizer to the positive electrode active material composition and / or the negative electrode active material composition to form pores inside the electrode plate.

[0177] The contents of the positive electrode active material, conductive material, binder and solvent are at levels commonly used in lithium batteries. One or more of the conductive material, binder and solvent may be omitted depending on the use and configuration of the lithium battery.

[0178] The binder content contained in the positive electrode is, for example, 0.1 to 10 wt% of the total weight of the positive electrode active material layer, or 0.1 to 5 wt%. The conductive material content contained in the positive electrode is, for example, 0.1 to 10 wt% of the total weight of the positive electrode active material layer, or 0.1 to 5 wt%. The content of the positive electrode active material contained in the positive electrode is, for example, 70 wt% to 99 wt%, 90 wt% to 99 wt%, or 95 wt% to 99 wt% of the total weight of the positive electrode active material layer.

[0179] The positive electrode current collector may include, for example, a base film and a metal layer disposed on one or both surfaces of the base film. The base film may include, for example, a polymer. The polymer may include, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI), or a combination thereof. The metal layer may include, for example, indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof. By having such a structure, the weight of the electrode can be reduced, and as a result, the energy density of the lithium battery can be improved.

[0180] Next, a separator inserted between the positive electrode and the negative electrode is provided.

[0181] Any separator can be used as long as it is commonly used in lithium batteries. For example, a separator with low resistance to ion movement of the electrolyte and excellent electrolyte moisture retention ability is used. The separator is, for example, selected from glass fiber, polyester, Teflon (registered trademark), polyethylene, polypropylene, polytetrafluoroethylene (PTFE), or a combination thereof, and is in the form of a non-woven fabric or a woven fabric. For lithium-ion batteries, a wound separator such as polyethylene or polypropylene is used, and for lithium-ion polymer batteries, a separator with excellent organic electrolyte impregnation ability is used.

[0182] The separator is manufactured by the following exemplary methods, but is not necessarily limited to such methods and is adjusted according to the required conditions.

[0183] First, a polymer resin, a filler, and a solvent are mixed to provide a separator composition. The separator composition is directly coated and dried on the upper part of the electrode to form a separator. In other embodiments, after the separator composition is cast and dried on a support, a separator film peeled off from the support is laminated on the upper part of the electrode to form a separator.

[0184] The polymer used in the production of the separator is not particularly limited, and any polymer that can be used as a binder for the electrode plate can be used. For example, vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride (PVDF), polyacrylonitrile, polymethyl methacrylate, or a mixture thereof is used.

[0185] Next, an electrolyte is provided.

[0186] The electrolyte is, for example, an organic electrolyte solution. The organic electrolyte solution is produced by dissolving a lithium salt in an organic solvent, for example.

[0187] Any organic solvent can be used as long as it is used as an organic solvent in the technical field. The organic solvent is, for example, propylene carbonate, ethylene carbonate, fluoroethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl isopropyl carbonate, dipropyl carbonate, dibutyl carbonate, benzonitrile, acetonitrile, tetrahydrofuran, 2-methyltetrahydrofuran, γ-butyrolactone, dioxolane, 4-methyldioxolane, N,N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dioxane, 1,2-dimethoxyethane, sulfolane, dichloroethane, chlorobenzene, nitrobenzene, diethylene glycol, dimethyl ether, or a mixture thereof.

[0188] Any lithium salt that is used as a lithium salt in the relevant art is also acceptable. Examples of lithium salts include LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(FSO2)2N, Li(CF3SO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, and LiN(C x F 2x+1 SO2)(C y F 2y+1 These include SO2 (1 ≤ x ≤ 20, 1 ≤ y ≤ 20), LiCl, LiI, or mixtures thereof.

[0189] In other embodiments, the electrolyte is also a solid electrolyte. The solid electrolyte is, for example, boron oxide or lithium oxynitride, but is not limited to these; any material used as a solid electrolyte in the art can be used. The solid electrolyte is formed on the negative electrode by, for example, sputtering, or a separate solid electrolyte sheet is laminated on the negative electrode.

[0190] Solid electrolytes include, for example, oxide-based solid electrolytes or sulfide-based solid electrolytes.

[0191] Solid electrolytes are, for example, oxide-based solid electrolytes. Oxide-based solid electrolytes include Li 1+x+y Al x Ti 2-x Si y P 3-y O 12( 0 <x<2、0≦y<3)、BaTiO3、Pb(Zr,Ti)O3(PZT)、Pb 1-x La x Zr 1-y Ti y O3(PLZT)(O≦x<1, O≦y<1), PB(Mg3Nb 2 / 3 )O3-PbTiO3(PMN-PT), HfO2, SrTiO3, SnO2, CeO2, Na2O, MgO, NiO, CaO, BaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiO2, Li3PO4, Li x Ti y (PO4)3(0 <x<2、0<y<3)、Li xAl y Ti z (PO4)3 (0 < x < 2, 0 < y < 1, 0 < z < 3), Li 1+x+y (Al, Ga) x (Ti, Ge) 2-x Si y P 3-y O 12 (0 ≤ x ≤ 1, 0 ≤ y ≤ 1), Li x La y TiO3 (0 < x < 2, 0 < y < 3), Li2O, LiOH, Li2CO3, LiAlO2, Li2O - Al2O3 - SiO2 - P2O5 - TiO2 - GeO2, Li 3+x La3M2O 12 (M = Te, Nb, or Zr, x is an integer from 1 to 10), and is selected from one or more of them. The solid electrolyte is produced by a sintering method or the like. For example, the oxide-based solid electrolyte is Li7La3Zr2O 12 (LLZO) and Li 3+x La3Zr 2-a M a O 12 (M doped LLZO, M = Ga, W, Nb, Ta, or Al, x is an integer from 1 to 10, 0 < a < 2), and is a garnet-type solid electrolyte selected from them.

[0192] The sulfide-based solid electrolyte may include, for example, lithium sulfide, silicon sulfide, phosphorus sulfide, boron sulfide, or a combination thereof. The sulfide-based solid electrolyte particles may include Li2S, P2S5, SiS2, GeS2, B2S3, or a combination thereof. The sulfide-based solid electrolyte particles may also be Li2S or P2S5. The sulfide-based solid electrolyte particles are known to have a high lithium ion conductivity compared to other inorganic compounds. For example, the sulfide-based solid electrolyte includes Li2S and P2S5. When the sulfide solid electrolyte material constituting the sulfide-based solid electrolyte includes Li2S - P2S5, the mixed molar ratio of Li2S:P2S5 is also, for example, in the range of about 50:50 to 90:10. Also, Li3PO4, halogen, halogen compounds, Li 2+2x Zn 1-x GeO4 (“LISICON”, 0 ≤ x < 1), Li 3+yPO 4-x N x ("LIPON", 0 < x < 4, 0 < y < 3), Li 3.25 Ge 0.25 P 0.75 Inorganic solid electrolytes such as S4 ("ThioLISICON"), Li2O - Al2O3 - TiO2 - P2O5 ("LATP") added to inorganic solid electrolytes of Li2S - P2S5, SiS2, GeS2, B2S3, or combinations thereof can be used as sulfide solid electrolytes. Non - limiting examples of sulfide solid electrolyte materials are: Li2S - P2S5; Li2S - P2S5 - LiX (X = halogen element); Li2S - P2S5 - Li2O; Li2S - P2S5 - Li2O - LiI; Li2S - SiS2; Li2S - SiS2 - LiI; Li2S - SiS2 - LiBr; Li2S - SiS2 - LiCl; Li2S - SiS2 - B2S3 - LiI; Li2S - SiS2 - P2S5 - LiI; Li2S - B2S3; Li2S - P2S5 - Z m S n (0 < m < 10, 0 < n < 10, Z = Ge, Zn or Ga); Li2S - GeS2; Li2S - SiS2 - Li3PO4; and Li2S - SiS2 - Li p MO q (0 < p < 10, 0 < q < 10, M = P, Si, Ge, B, Al, Ga or In). In connection with this, sulfide - based solid electrolyte materials can be produced by treating starting materials of sulfide - based solid electrolyte substances (e.g., Li2S, P2S5, etc.) by methods such as the melt quenching method, mechanical milling method, etc. Also, a calcination process can be carried out after the said treatment. Sulfide - based solid electrolytes can be amorphous, crystalline, or in a mixed state of them.

[0193] Referring to Figure 5, a lithium battery 1 according to one embodiment includes a positive electrode 3, a negative electrode 2, and a separator 4. The positive electrode 3, negative electrode 2, and separator 4 are wound or folded to form a battery structure 7. The formed battery structure 7 is housed in a battery case 5. An organic electrolyte is injected into the battery case 5 and sealed with a cap assembly 6 to complete the lithium battery 1. The battery case 5 is cylindrical, but is not necessarily limited to such a shape; for example, it may be angular, thin film, etc.

[0194] Referring to Figure 6, a lithium battery 1 according to one embodiment includes a positive electrode 3, a negative electrode 2, and a separator 4. The separator 4 is positioned between the positive electrode 3 and the negative electrode 2, and the positive electrode 3, negative electrode 2, and separator 4 are wound or folded to form a battery structure 7. The formed battery structure 7 is housed in a battery case 5. It may include electrode tabs 8 that serve as electrical pathways for guiding the current formed in the battery structure 7 to the outside. An organic electrolyte is injected into the battery case 5 and sealed to complete the lithium battery 1. The battery case 5 is rectangular in shape, but is not necessarily limited to such a shape; for example, it may be cylindrical, thin film, etc.

[0195] Referring to Figure 7, a lithium battery 1 according to one embodiment includes a positive electrode 3, a negative electrode 2, and a separator 4. The separator 4 is placed between the positive electrode 3 and the negative electrode 2 to form the battery structure. After the battery structures 7 are stacked in a bicell structure, they are housed in a battery case 5. The battery may include electrode tabs 8 that serve as electrical pathways for guiding the current formed in the battery structure 7 to the outside. The lithium battery 1 is completed when an organic electrolyte is injected into the battery case 5 and it is sealed. The battery case 5 is rectangular in shape, but is not necessarily limited to such a shape; for example, it may be cylindrical, thin film, etc.

[0196] Pouch-type lithium batteries correspond to the lithium batteries shown in Figures 5 to 7, where a pouch is used as the battery case. A pouch-type lithium battery includes one or more battery structures. A separator is placed between the positive and negative electrodes to form the battery structure. After the battery structures are stacked in a bicell structure, they are impregnated with an organic electrolyte, housed in a pouch, and sealed to complete the pouch-type lithium battery. For example, although not shown, the positive electrode, negative electrode, and separator described above may be simply stacked and housed in a pouch in the form of an electrode assembly, or they may be wound into a jelly roll form of an electrode assembly, or folded, and then housed in a pouch. Next, the organic electrolyte is injected into the pouch and sealed to complete the lithium battery.

[0197] Lithium batteries are used in electric vehicles (EVs) due to their excellent lifespan and high efficiency characteristics. For example, they are used in hybrid vehicles such as plug-in hybrid electric vehicles (PHEVs). They are also used in fields where large amounts of power storage are required, such as electric bicycles and power tools.

[0198] Lithium batteries are stacked in multiples to form battery modules, and multiple battery modules form a battery pack. Such battery packs can be used in all devices that require high capacity and high output. For example, they can be used in notebook computers, smartphones, electric vehicles, etc. A battery module includes, for example, multiple batteries and a frame that secures them. A battery pack includes, for example, multiple battery modules and bus bars that connect them. Battery modules and / or battery packs may further include cooling devices. Multiple battery packs are regulated by a battery management system. The battery management system includes battery packs and battery control devices connected to the battery packs.

[0199] A dry anode according to another embodiment includes an electrode current collector and the dry anode film described above, which is disposed on one or both sides of the electrode current collector.

[0200] By including a dry-type negative electrode film in the dry-type negative electrode, the internal resistance of the dry-type negative electrode is reduced and the mechanical properties are improved.

[0201] The electrode current collector may include, for example, a base material.

[0202] The material constituting the base material (substrate) is a material that does not react with lithium, that is, a material that does not form an alloy or compound with lithium, and any material having conductivity can be used. The base material is, for example, a metal or an alloy. The base material can consist of, for example, indium (In), copper (Cu), magnesium (Mg), stainless steel (SUS), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), or an alloy thereof. The base material has a form selected from, for example, a sheet, a foil, a film, a plate-like body, a porous body, a mesoporous body, a through-hole-containing body, a polygonal ring body, a mesh body, a foam, and a non-woven fabric body, but is not necessarily limited to such a form, and any form used in the technical field can be used.

[0203] The electrode current collector may include, for example, a base material; and an interlayer disposed between the base material and the dry-type negative electrode film. The interlayer may include, for example, a carbon-based conductive material.

[0204] The interlayer is disposed directly, for example, on one or both surfaces of the base material. Therefore, there may be no other layer disposed between the base material and the interlayer. By disposing the interlayer directly on one or both surfaces of the base material, the adhesion between the base material and the dry-type negative electrode film can be further improved.

[0205] The thickness of the intermediate layer is, for example, 0.01-30%, 0.1-30%, 0.5-30%, 1-25%, 1-20%, 1-15%, 1-10%, 1-5%, or 1-3% of the substrate thickness. The thickness of the intermediate layer is, for example, 10nm-5μm, 50nm-5μm, 200nm-4μm, 500nm-3μm, 500nm-2μm, 500nm-1.5μm, or 700nm-1.3μm. Having the intermediate layer in such a range of thickness further improves the bonding strength between the substrate and the dry anode film and suppresses the increase in interfacial resistance.

[0206] The intermediate layer may include, for example, a carbon-based conductive material. The carbon-based conductive material included in the intermediate layer may be selected from among the carbon-based conductive materials used in the dry anode film. The intermediate layer may include the same carbon-based conductive material as the carbon-based conductive material used in the dry anode film. Because the intermediate layer includes a carbon-based conductive material, the intermediate layer is also, for example, a conductive layer.

[0207] The intermediate layer may additionally include, for example, a binder. The additional inclusion of a binder in the intermediate layer can further improve the bonding strength between the substrate and the dry negative electrode film. The binder included in the intermediate layer may be, for example, a conductive binder or a non-conductive binder. Conductive binders may be, for example, ionically conductive binders and / or electronically conductive binders. A binder possessing both ionically and electronically conductive properties may belong to both the ionically conductive binder and the electronically conductive binder category.

[0208] The binder included in the intermediate layer may be selected from among the binders used in dry anode films. The intermediate layer may contain the same binder as the binder used in dry anode films. The binder included in the intermediate layer may be, for example, a fluorine-based binder. The fluorine-based binder included in the intermediate layer may be, for example, polyvinylidene fluoride (PVDF). The intermediate layer may also be, for example, a binder-containing binder layer. The intermediate layer may also be, for example, a conductive layer containing a binder and a carbon-based conductive material.

[0209] The intermediate layer can be disposed on the substrate by, for example, a dry or wet method. The intermediate layer can be disposed on the substrate by, for example, vapor deposition such as CVD or PVD. The intermediate layer can be disposed on the substrate by, for example, spin coating or dip coating. The intermediate layer can be disposed on the substrate by, for example, vapor deposition of a carbon-based conductive material onto the substrate. A dry-coated intermediate layer consists of a carbon-based conductive material and does not contain a binder. The intermediate layer can be disposed on the substrate by, for example, coating the substrate surface with a composition containing a carbon-based conductive material, a binder, and a solvent and drying it. The intermediate layer has a single-layer structure or a multilayer structure including multiple layers, for example, a two-layer structure, a three-layer structure, or a four-layer structure.

[0210] The dry anode film contained in the dry anode corresponds to the electrode active material layer.

[0211] The dry anode includes a dry anode film, and the dry anode film includes a dry anode active material having the core / shell structure described above.

[0212] The dry anode active material having the core / shell structure described above comprises a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof in the core, and a first metal oxide and a first carbon-based material in the shell.

[0213] The dry anode active material may additionally include conventional dry anode active materials in addition to the dry anode active material having the core / shell structure described above. Any conventional dry anode active material commonly used in this industry may be used without limitation.

[0214] Any dry-type negative electrode active material can be used as long as it is used as a negative electrode active material for a lithium battery in the relevant technical field. For example, it includes one or more selected from the group consisting of lithium metal, a metal alloyable with lithium, a transition metal oxide, a non-transition metal oxide, and a carbon-based material. The metal alloyable with lithium is, for example, Si, Sn, Al, Ge, Pb, Bi, Sb, a Si-Y alloy (where Y is an alkali metal, an alkaline earth metal, a Group 13 element, a Group 14 element, a transition metal, a rare earth element, or a combined element thereof and not Si), a Sn-Y alloy (where Y is an alkali metal, an alkaline earth metal, a Group 13 element, a Group 14 element, a transition metal, a rare earth element, or a combined element thereof and not Sn), etc. The element Y is, for example, Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Ti, Ge, P, As, Sb, Bi, S, Se, Te, Po, or a combination thereof. The transition metal oxide is, for example, lithium titanate, vanadium oxide, lithium vanadate, etc. The non-transition metal oxide is, for example, SnO2, SiO x (0 < x < 2), etc. The carbon-based material is, for example, crystalline carbon, amorphous carbon, or a mixture thereof. The crystalline carbon is, for example, graphite such as amorphous, plate-like, flaky, spherical, or fibrous natural graphite or artificial graphite. The amorphous carbon is, for example, soft carbon (low-temperature calcined carbon) or hard carbon, mesophase pitch carbide, calcined coke, etc.

[0215] For the positive electrode active material, for example, one or more of composite oxides of metals selected from cobalt, manganese, nickel, and combinations thereof with lithium are used, and specific examples are as described above.

[0216] A dry anode is, for example, a dry anode. A dry anode includes a dry anode film, and the dry anode film includes a dry anode active material.

[0217] In another embodiment, the lithium battery includes a first electrode; a second electrode; and an electrolyte disposed between the first electrode and the second electrode, wherein the first electrode, the second electrode, or a combination thereof is the dry anode described above.

[0218] The lithium battery's cycle characteristics are improved by incorporating a dry negative electrode with reduced internal resistance and improved mechanical properties.

[0219] A lithium battery may, for example, include a dry negative electrode, or include a dry negative electrode and a dry positive electrode. A lithium battery may, for example, include a dry negative electrode and a wet positive electrode, or include a dry positive electrode and a dry negative electrode.

[0220] A lithium battery contains an electrolyte, which may include, for example, a liquid electrolyte, a solid electrolyte, a gel electrolyte, or a combination thereof.

[0221] Liquid electrolytes are, for example, organic electrolytes. Organic electrolytes are prepared, for example, by dissolving lithium salts in organic solvents.

[0222] Any organic solvent that is used as an organic solvent in the relevant art is acceptable. Examples of organic solvents include propylene carbonate, ethylene carbonate, fluoroethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl isopropyl carbonate, dipropyl carbonate, dibutyl carbonate, benzonitrile, acetonitrile, tetrahydrofuran, 2-methyltetrahydrofuran, γ-butyrolactone, dioxolane, 4-methyldioxolane, N,N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dioxane, 1,2-dimethoxyethane, sulfolane, dichloroethane, chlorobenzene, nitrobenzene, diethylene glycol, dimethyl ether, or mixtures thereof.

[0223] Any lithium salt that is used as a lithium salt in the relevant art is also acceptable. Examples of lithium salts include LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(CF3SO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, and LiN(C x F 2x+1 SO2)(C y F 2y+1 SO2 (where x and y are natural numbers), LiCl, LiI, or mixtures thereof, etc.

[0224] Solid electrolytes may include, for example, inorganic solid electrolytes, organic solid electrolytes, combined inorganic and solid electrolytes, or combinations thereof.

[0225] Solid electrolytes may include, for example, oxide-based solid electrolytes, sulfide-based solid electrolytes, polymer-based solid electrolytes, or combinations thereof.

[0226] The solid electrolyte is, for example, boron oxide or lithium oxynitride, but is not limited to these; any solid electrolyte used in the relevant art can be used. The solid electrolyte is formed on the negative electrode by a method such as sputtering, or a separate solid electrolyte sheet is laminated on the negative electrode.

[0227] Oxide-based solid electrolytes include, for example, Li 1+x+y Al x Ti 2-x Si y P 3-y O 12( 0 <x<2、0≦y<3)、BaTiO3、Pb(Zr,Ti)O3(PZT)、Pb 1-x La x Zr 1-y Ti y O3(PLZT, 0≦x<1, 0≦y<1), PB(Mg3Nb 2 / 3 )O3-PbTiO3(PMN-PT), HfO2, SrTiO3, SnO2, CeO2, Na2O, MgO, NiO, CaO, BaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiO2, Li3PO4, Li x Ti y (PO4)3(0 <x<2、0<y<3)、Li x Al y Ti z (PO4)3(0 <x<2、0<y<1、0<z<3)、Li 1+x+y (Al, Ga) x (Ti, Ge) 2-x Si y P 3-y O 12 (0≦x≦1 0≦y≦1), Li x La y TiO3(0 <x<2、0<y<3)、Li2O、LiOH、Li2CO3、LiAlO2、Li2O-Al2O3-SiO2-P2O5-TiO2-GeO2、Li 3+x La3M2O 12 (M = Te, Nb, or Zr, 0≦x≦10), Li 3+x La3Zr 2-y M y O 12(M-doped LLZO, M = Ga, W, Nb, Ta, Al or combinations thereof, 0 ≦ x ≦ 10, 0 < y < 2), Li7La3Zr 2-x Ta x O 12 (0 < x < 2, LLZ-Ta), or combinations thereof. The oxide-based solid electrolyte is, for example, a garnet-type solid electrolyte. The oxide-based solid electrolyte is produced by a sintering method or the like.

[0228] The oxide-based solid electrolyte is, for example, Li7La3Zr2O 12 (LLZO), Li 6.5 La3Zr 1.5 Ta 0.5 O 12 , Li 1.3 Al 0.3 Ti 1.7 (PO4)3, Li 0.34 La 0.51 TiO 2.94 , Li 1.07 Al 0.69 Ti 1.46 (PO4)3, 50Li4SiO4 - 50Li2BO3, 90Li3BO3 - 10Li2SO4, Li 2.9 PO 3.3 N 0.46 , or combinations thereof.

[0229] The sulfide-based solid electrolyte is, for example, Li2S - P2S5, Li2S - P2S5 - LiX, X is a halogen element, Li2S - P2S5 - Li2O, Li2S - P2S5 - Li2O - LiI, Li2S - SiS2, Li2S - SiS2 - LiI, Li2S - SiS2 - LiBr, Li2S - SiS2 - LiCl, Li2S - SiS2 - B2S3 - LiI, Li2S - SiS2 - P2S5 - LiI, Li2S - B2S3, Li2S - P2S5 - Z m S n , m, n are positive numbers, Z is one of Ge, Zn or Ga, Li2S - GeS2, Li2S - SiS2 - Li3PO4, Li2S - SiS2 - Li p MO q , p, q are positive numbers, M is one of P, Si, Ge, B, Al, GaIn, Li7-x PS 6-x Cl x , 0≦x≦2, Li 7-x PS 6-x Br x , 0≦x≦2, and Li 7-x PS 6-x I x The x-axis is one or more selected from 0 ≤ x ≤ 2. Sulfide-based solid electrolytes are prepared by processing starting materials such as Li2S and P2S5 by methods such as melt-quenching or mechanical milling. Heat treatment may also be performed after such processing. Sulfide-based solid electrolytes can be amorphous, crystalline, or a mixture of both.

[0230] Sulfide-based solid electrolytes may include, for example, argyrodite-type solid electrolytes represented by the following chemical formula 9: <Chemical formula 9> Li + 12-n-x A n+ X 2- 6-x Y - x In the above formula, A is P, As, Ge, Ga, Sb, Si, Sn, Al, In, Ti, V, Nb, or Ta, X is S, Se, or Te, Y is Cl, Br, I, F, CN, OCN, SCN, or N3, and 1 ≤ n ≤ 5 and 0 ≤ x ≤ 2.

[0231] Sulfide-based solid electrolytes include Li 7-x PS 6-x Cl x , 0≦x≦2, Li 7-x PS 6-x Br x , 0≦x≦2, and Li 7-x PS 6-x I xIt is also an argyrodite-type compound containing one or more values ​​selected from 0 ≤ x ≤ 2. In particular, the sulfide-based solid electrolyte contained in the solid electrolyte is also an argyrodite-type compound containing one or more values ​​selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0232] Polymer-based solid electrolytes include, for example, solid electrolytes containing ion-conducting polymers and lithium salts, solid electrolytes containing ionic liquid polymers and lithium salts, or combinations thereof.

[0233] Ion-conducting polymers are polymers that contain ion-conducting repeating units in their main chain or side chains. Ion-conducting repeating units are units that possess ion conductivity, such as alkylene oxide units or new aqueous units. Ion-conducting polymers may contain, for example, ether monomers, acrylic monomers, methacrylic monomers, siloxane monomers, or combinations thereof as ion-conducting repeating units. Ion-conducting polymers may also include, for example, polyethylene oxide, polypropylene oxide, polymethyl methacrylate, polyethyl methacrylate, polydimethylsiloxane, polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polyethyl acrylate, poly2-ethylhexyl acrylate, polybutyl methacrylate, poly2-ethylhexyl methacrylate, polydecyl acrylate, polyethylene vinyl acetate, or combinations thereof. Ion-conducting polymers include, for example, polyethylene oxide (PEO), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyvinyl sulfone, or combinations thereof.

[0234] A polymeric ionic liquid (PIL) is, for example, i) one or more cations selected from ammonium, pyrrolidinium, pyridinium, pyrimidinium, imidazolium, piperidinium, pyrazolium, oxazolium, pyridazinium, phosphonium, sulfonium, triazole, and mixtures thereof, and ii) BF4-, PF6-, AsF6-, SbF6-, AlCl4-, HSO4-, ClO4-, CH3SO3-, CF3CO2-, (CF3SO2)2N-, Cl-, Br-, I-, SO4 - , PF6-, ClO4-, CF3SO3-, CF3CO2-, (C2F5SO2)2N-, (C2F5SO2)(CF3SO2)N-, NO3 - Al2Cl7 - AsF6 - SbF6 - 、 CF3COO - CH3COO - CF3SO3 - (CF3SO2)3C - , (CF3CF2SO2)2N - 、 (CF3)2PF4 - (CF3)3PF3 - (CF3)4PF2 - (CF3)5PF - (CF3)6P - , SF5CF2SO3 - ,SF5CHFCF2SO3 - CF3CF2(CF3)2CO - (CF3SO2) 2CH - (SF5)3C - (O(CF3)2C2(CF3)2O)2PO -The ionic liquid polymer may contain repeating units comprising one or more anions selected from (CF3SO2)2N-. Examples of ionic liquid polymers include poly(diallyldimethylammonium)TFSI, poly(1-allyl-3-methylimidazolium trifluoromethanesulfonylimide), poly((N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide), or combinations thereof.

[0235] Lithium salts include, for example, LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(CF3SO2)2N, Li(FSO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, and LiN(C) x F 2x+1 SO2)(C y F 2y+1 SO2 (1 ≤ x ≤ 20, 1 ≤ y ≤ 20), LiCl, LiI, or a combination thereof.

[0236] A dry anode manufacturing method according to another embodiment is provided.

[0237] A method for manufacturing a dry anode includes the steps of: providing a dry anode film; and arranging the dry electrode film on one or both sides of an electrode current collector.

[0238] The steps of providing a dry anode film include: preparing a dry mixture by dry mixing a dry anode active material and a dry binder; and preparing a dry anode film by molding the dry mixture.

[0239] First, a dry mixture is prepared by dry mixing the negative electrode active material and the dry binder. For example, a dry mixture is provided, which is a dry mixture of the dry negative electrode active material and the dry binder.

[0240] The dry mixture may further contain a dry conductive material.

[0241] Dry mixing means mixing without the presence of a process solvent. The process solvent is, for example, the solvent used in the manufacture of the electrode slurry. The process solvent may be, for example, water, NMP, etc., or is not limited to these, as long as it is a process solvent used in the manufacture of the electrode slurry. Dry mixing can be carried out using a stirrer at a rotational speed of 10 to 10,000 rpm at a temperature of, for example, 15°C to 65°C. Dry mixing can be carried out using a stirrer for, for example, 1 to 200 minutes.

[0242] Dry mixing can be performed, for example, one or more times. First, a first dry mixture can be prepared by primary dry mixing of the dry negative electrode active material, dry conductive material, and dry binder. Primary dry mixing can be performed, for example, at a temperature of 25 to 65°C, at a rotation speed of 10 to 2000 rpm or less, for a time of 15 minutes or less. Next, a second mixture can be prepared by additional secondary dry mixing of the first dry mixture. Secondary dry mixing can be performed, for example, at a temperature of 25 to 65°C, at a rotation speed of 3000 to 9000 rpm, for 10 to 60 minutes. Secondary dry mixing yields a dry mixture containing a fibrillated dry binder.

[0243] The agitator is, for example, a kneader. The agitator includes, for example, a chamber; one or more rotating shafts located inside the chamber and rotating; and blades rotatably coupled to the rotating shafts and positioned longitudinally along the rotating shafts. The blades are, for example, one or more selected from ribbon blades, sigma blades, jet (Z) blades, dispersion blades, and screw blades. The inclusion of blades allows for effective mixing of electrode active materials, dry conductive materials, and dry binders without solvents to produce a mixture in a dough-like form.

[0244] Dry binders used include, for example, vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polytetrafluoroethylene (PTFE), mixtures of the aforementioned polymers, and styrene-butadiene rubber-based polymers. The dry binder can be selected from among the dry binders used for the dry negative electrode film described above.

[0245] Dry conductive materials include, but are not limited to, carbon black, graphite nanoparticles, natural graphite, artificial graphite, acetylene black, Ketjenblack, carbon fibers, carbon nanotubes, metal powders such as copper, nickel, aluminum, and silver, or metal fibers or tubes, and conductive polymers such as polyphenylene derivatives. Any conductive material usable in the relevant art is acceptable. The conductive material is, for example, a carbon-based conductive material. The dry conductive material can be selected from among the dry conductive materials used in the dry negative electrode film described above.

[0246] It is also possible to further add a plasticizer or pore-forming agent to the dry mixture to form pores inside the electrode plate.

[0247] The content of the dry anode active material, dry binder, and dry conductive material used in the dry anode film is at levels typically used in lithium batteries.

[0248] The dry positive electrode film contains a dry positive electrode active material as the positive electrode active material. The dry positive electrode active material refers to the dry negative electrode film described above. The dry negative electrode film uses a dry negative electrode active material as the negative electrode active material. The dry negative electrode active material refers to the dry negative electrode film described above.

[0249] Next, the dry mixture is molded to prepare the dry anode film.

[0250] The manufactured dry mixture can be fed into an extruder and extruded into a sheet or film. The extrusion pressure is, for example, 4 MPa to 100 MPa.

[0251] Next, an electrode current collector is provided, in which an intermediate layer is disposed on one or both sides of a base material.

[0252] The step of providing an electrode current collector having an intermediate layer disposed on one or both sides of a substrate includes, for example, the step of providing a substrate; and the step of distributing the intermediate layer on one or both sides of the substrate.

[0253] The substrate of the electrode current collector refers to the electrode current collector portion described above. The substrate of the positive electrode current collector is, for example, aluminum foil. The substrate of the negative electrode current collector is, for example, copper foil.

[0254] The step of placing an intermediate layer on one or both sides of a substrate includes dry coating and / or wet coating. Dry coating involves, for example, coating one or both sides of an electrode current collector with a carbon-based conductive material and / or its precursor by vapor deposition. Vapor deposition is performed at room temperature or high temperature and at atmospheric pressure or vacuum pressure. If the intermediate layer placed by dry coating consists of a carbon-based material, it does not contain a binder. Wet coating involves, for example, coating one or both sides of an electrode current collector with a composition containing a carbon-based conductive material and a binder. The composition includes, for example, a carbon-based conductive material, a binder, and a process solvent. For the carbon-based conductive material and binder, refer to the electrode portion described above. The process solvent may be selected from among the solvents used in the manufacture of the electrode slurry. The process solvent is removed by drying after the composition has been coated onto the electrode current collector. The coating method is, but is not limited to, spin coating, dip coating, etc., and any coating method used in the art can be used.

[0255] Next, the dry negative electrode is manufactured by simultaneously or sequentially placing the dry negative electrode film on one or both sides of the electrode current collector.

[0256] A rolling step may be added during and / or after the placement of the dry negative electrode film on one or both sides of the electrode current collector.

[0257] Rolling can be done using methods such as roll presses and plate presses, but is not necessarily limited to these. The pressure during rolling is, for example, 1.0 to 10.0 ton / cm. If the pressure during rolling increases excessively, cracks may occur in the electrode current collector. If the pressure during rolling is too low, the bonding force between the electrode current collector and the dry negative electrode film may be reduced.

[0258] Lithium batteries are manufactured, for example, by the exemplary methods described below, but are not necessarily limited to such methods, and may vary depending on the required conditions.

[0259] First, one or both of the positive and negative electrodes may be manufactured by the dry negative electrode manufacturing method described above. In other embodiments, if one of the positive and negative electrodes is manufactured by the electrode manufacturing method described above, the other electrode may be manufactured by a wet manufacturing method. For example, the other electrode may be manufactured by producing an electrode slurry containing an electrode active material, a conductive material, a binder, and a solvent, and then coating the manufactured electrode slurry onto an electrode current collector and drying it. The conductive material and binder included in the electrode manufactured by the wet method may be selected from the conductive material and binder used in the manufacture of the dry negative electrode described above.

[0260] Next, a separator is provided to be inserted between the positive and negative electrodes.

[0261] The steps of providing a dry anode film include preparing a dry mixture by dry mixing a dry anode active material and a dry binder as described above; and preparing a dry anode film by molding the dry mixture.

[0262] The dry anode active material can be formed during the dry mixing process of the core and composite.

[0263] The composite comprises one or more first metal oxides; and a first carbon-based material, wherein the first metal oxide is arranged within a matrix of the first carbon-based material, and the first metal oxide has chemical formula M a O b(0 < a ≤ 3, 0 < b < 4, and if a is 1, 2, or 3, then b is not an integer), and M is one or more metals selected from Groups 2 to 16 of the Periodic Table of the Elements.

[0264] The step of providing the composite includes, for example, the step of providing the composite by supplying a reaction gas composed of a carbon source gas to a structure containing a metal oxide and performing heat treatment. The step of providing the composite includes, for example, M a O c including the step of manufacturing the composite by supplying a reaction gas composed of a carbon source gas to one or more second metal oxides represented by (0 < a ≤ 3, 0 < c ≤ 4, and when a is 1, 2, or 3, b is an integer) and performing heat treatment, and M is one or more metals selected from Groups 2 to 13, 15, and 16 of the Periodic Table of the Elements.

[0265] The carbon source gas is a gas composed of a compound represented by the following Chemical Formula 10, or one or more mixed gases selected from the group consisting of a compound represented by the following Chemical Formula 10, a compound represented by the following Chemical Formula 11, and an oxygen-containing gas represented by the following Chemical Formula 12. <Chemical Formula 10> C n H (2n+2-a) [OH] a In the Chemical Formula 10, n is 1 to 20, and a is 0 or 1; <Chemical Formula 11> C n H 2n In the Chemical Formula 11, n is 2 to 6; <Chemical Formula 12> C x H y O z In the Chemical Formula 12, x is 0 or an integer from 1 to 20, y is 0 or an integer from 1 to 20, and z is 1 or 2.

[0266] The compound represented by Chemical Formula 10 and the compound represented by Chemical Formula 11 are one or more selected from the group consisting of methane, ethylene, propylene, methanol, ethanol, and propanol. The oxygen-containing gas represented by Chemical Formula 12 includes, for example, carbon dioxide (CO2), carbon monoxide (CO), water vapor (H2O), or a mixture thereof.

[0267] M a O c After the step of supplying a reaction gas composed of a carbon source gas to the second metal oxide represented by (0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer) and performing heat treatment, a cooling step using one or more inert gases selected from the group consisting of nitrogen, helium, and argon is further performed. The cooling step refers to the step of adjusting to room temperature (20 - 25°C). The carbon source gas may include one or more inert gases selected from the group consisting of nitrogen, helium, and argon.

[0268] In the method for producing a composite, the process of growing a carbon-based material, such as graphene, by a gas-phase reaction can be carried out under various conditions.

[0269] According to the first condition, for example, M a O c First, methane is supplied to a reactor in which a second metal oxide represented by (0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer) is disposed, and the temperature is raised to the heat treatment temperature (T). The temperature raising time to the heat treatment temperature (T) is 10 minutes to 4 hours, and the heat treatment temperature (T) is in the range of 700°C to 1100°C. Heat treatment is carried out during the reaction time at the heat treatment temperature (T). The reaction time is, for example, 4 hours to 8 hours. The heat-treated product is cooled to room temperature to produce a composite. The time taken during the process of cooling from the heat treatment temperature (T) to room temperature is, for example, 1 hour to 5 hours.

[0270] According to the second condition, for example, M a O cHydrogen is first supplied to a reactor in which a second metal oxide represented by (0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer) is disposed, and the temperature is raised to a heat treatment temperature (T). The temperature raising time to the heat treatment temperature (T) is 10 minutes to 4 hours, and the heat treatment temperature (T) is in the range of 700°C to 1100°C. After heat treatment for a certain reaction time at the heat treatment temperature (T), methane gas is supplied and heat treatment is carried out for the remaining reaction time. The reaction time is, for example, 4 hours to 8 hours. The heat-treated product is cooled to room temperature to produce a composite. Nitrogen is supplied during the cooling process. The time taken for the cooling process from the heat treatment temperature (T) to room temperature is, for example, 1 hour to 5 hours.

[0271] According to the third condition, for example, M a O c Hydrogen is first supplied to a reactor in which a second metal oxide represented by (0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer) is disposed, and the temperature is raised to a heat treatment temperature (T). The temperature raising time to the heat treatment temperature (T) is 10 minutes to 4 hours, and the heat treatment temperature (T) is in the range of 700°C to 1100°C. After heat treatment for a certain reaction time at the heat treatment temperature (T), a mixed gas of methane and hydrogen is supplied and heat treatment is carried out for the remaining reaction time. The reaction time is, for example, 4 hours to 8 hours. The heat-treated product is cooled to room temperature to produce a composite. Nitrogen is supplied during the cooling process. The time taken for the cooling process from the heat treatment temperature (T) to room temperature is, for example, 1 hour to 5 hours.

[0272] In the process of producing the composite, when the carbon source gas contains water vapor, a composite having very excellent conductivity can be obtained. The content of water vapor in the gas mixture is not limited, and is, for example, 0.01% by volume to 10% by volume based on 100% by volume of the entire carbon source gas. The carbon source gas is, for example, methane; a mixed gas containing methane and an inert gas; or a mixed gas containing methane and an oxygen-containing gas.

[0273] Carbon source gases include, for example, methane; a mixture of methane and carbon dioxide; or a mixture of methane, carbon dioxide, and water vapor. In a mixture of methane and carbon dioxide, the molar ratio of methane to carbon dioxide is approximately 1:0.20 to 1:0.50, approximately 1:0.25 to 1:0.45, or approximately 1:0.30 to 1:0.40. In a mixture of methane, carbon dioxide, and water vapor, the molar ratio of methane, carbon dioxide, and water vapor is approximately 1:0.20 to 0.50:0.01 to 1.45, approximately 1:0.25 to 0.45:0.10 to 1.35, or approximately 1:0.30 to 0.40:0.50 to 1.0.

[0274] Carbon source gases include, for example, carbon monoxide or carbon dioxide. Another example is a mixture of methane and nitrogen. In this mixture, the molar ratio of methane to nitrogen is approximately 1:0.20–1:0.50, 1:0.25–1:0.45, or 1:0.30–1:0.40. Carbon source gases do not contain inert gases such as nitrogen.

[0275] The heat treatment pressure can be selected considering the heat treatment temperature, the composition of the gas mixture, and the desired amount of carbon coating. The heat treatment pressure can be controlled by adjusting the amount of gas mixture flowing in and out. Examples of heat treatment pressures include 0.5 atm or higher, 1 atm or higher, 2 atm or higher, 3 atm or higher, 4 atm or higher, or 5 atm or higher. Examples of heat treatment pressures include 0.5 atm to 10 atm, 1 atm to 10 atm, 2 atm to 10 atm, 3 atm to 10 atm, 4 atm to 10 atm, or 5 atm to 10 atm.

[0276] The heat treatment time is not particularly limited and can be appropriately adjusted according to the heat treatment temperature, the pressure during heat treatment, the composition of the gas mixture, and the amount of the desired carbon coating. For example, the reaction time at the heat treatment temperature is, for example, 10 minutes to 100 hours, 30 minutes to 90 hours, or 50 minutes to 40 hours. For example, as the heat treatment time increases, the amount of carbon deposited, for example, the amount of graphene (carbon), increases, whereby the electrical properties of the composite can be improved. However, such a tendency is not necessarily directly proportional to the time. For example, after a predetermined time has elapsed, no further carbon deposition, for example, graphene deposition, may occur or the deposition rate may decrease.

[0277] Even at a relatively low temperature through the gas-phase reaction of the above-described carbon source gas, M a O c (0 < a ≤ 3, 0 < c ≤ 4, if a is 1, 2, or 3, then c is an integer) and the reduction product thereof, M a O b By providing a uniform carbon-based material coating, for example, a graphene coating, on one or more selected from the first metal oxides represented by (0 < a ≤ 3, 0 < b < 4, a is 1, 2, or 3, and b is not an integer), a composite is obtained.

[0278] The composite has, for example, a matrix of a carbon-based material having one or more structures selected from a spherical structure, a spiral structure in which a plurality of spherical structures are connected, a cluster structure in which a plurality of spherical structures are aggregated, and a sponge structure, for example, a graphene matrix, and M disposed in the graphene matrix a O b (0 < a ≤ 3, 0 < b < 4, a is 1, 2, or 3, and b is not an integer) and the first metal oxide represented by a O cIt contains one or more selected from the second metal oxides represented by (0 < a ≤ 3, 0 < c ≤ 4, and if a is 1, 2, or 3, c is an integer).

[0279] The content of the dry binder is 1 to 10% by weight, 1 to 5% by weight, or 1.5 to 3.5% by weight, or 1.5 to 3% by weight based on 100% by weight of the total content of the core, the composite, and the dry binder.

[0280] The content of the composite containing one or more selected from the first metal oxide and the first carbonaceous material is about 5% by weight or less based on the total weight of the dry negative electrode film.

[0281] The present invention will be described in more detail through the following examples and comparative examples. However, the examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

[0282] (Production of composite) Production Example 1: Al2O3@Gr composite After placing Al2O3 particles (average particle size: about 20 nm) in the reactor, the temperature inside the reactor was raised to 1000 °C at a heating rate of about 23 °C / min under the condition that CH4 was supplied into the reactor at about 300 sccm and 1 atm for about 30 minutes.

[0283] Next, heat treatment was performed by holding at the above temperature for 7 hours. Then, the supply of CH4 was interrupted, and the internal temperature of the reactor was adjusted to room temperature (25 °C) to obtain a composite in which Al2O3 particles and Al2O z (0 < z < 3) particles were embedded in graphene.

[0284] The alumina content contained in the composite was 60 wt%. <​​​​​

[0286] Production Example 3: SiO2@Gr Composite After placing SiO2 particles (average particle size: about 15 nm) in the reactor, the internal temperature of the reactor was raised to 1000 °C under the condition that CH4 was supplied to the reactor at about 300 sccm and 1 atm for about 30 minutes.

[0287] Subsequently, heat treatment was performed by holding at the above temperature for 7 hours. Then, the internal temperature of the reactor was adjusted to room temperature (20 - 25 °C) to obtain a composite in which SiO y (0 < y < 2) particles were embedded in graphene.

[0288] (Production of Silicon-Based Anode Active Material) Production Example 4 Scaly graphite (SFG6) (Timcal, AG) (particle size: 4 μm, specific surface area: 17 m 2 / g), pitch, and silicon were wet-mixed at a weight ratio of 2:25:73 using an isopropyl alcohol (IPA) solvent, and this was spray-dried. Subsequently, the dried product was carbonized at 900 °C to obtain a silicon-carbon composite (SCN) (D50: about 13 μm).

[0289] (Production of Lithium Battery (Full Cell), Dry Anode) Example 1: Dry Anode Film Containing Graphite, GB 0.5% and Binder (Production of Dry Anode) Graphite, which is the first anode active material, polytetrafluoroethylene (PTFE) as a dry binder, and the composite (GB) prepared in Production Example 1 were put into a blade mixer at a weight ratio of 97.5:2.0:0.5, and then primary dry mixing was performed at 25 °C at a speed of 1200 rpm for 10 minutes to prepare a first dry mixture in which the dry anode active material and the dry binder were uniformly mixed.

[0290] Next, to promote the fiberization (e.g., fibrillation) of the binder, the first mixture was further secondary-mixed at 25°C at a speed of 5000 rpm for 20 minutes to prepare the second mixture. No additional solvents were used in the preparation of the first and second mixtures.

[0291] The prepared second mixture was fed into an extruder and extruded to prepare a dry anode film as a sheet-like self-standing film of the anode active material layer. The extrusion pressure was 50 MPa. The dry anode film contains a composite anode active material having a structure in which a shell containing the composite and / or its milling results is coated on a graphite core.

[0292] A first laminate was prepared in which a carbon layer was placed as an interlayer on one surface of a 12 μm thick copper thin film, and the interlayer was placed on one surface of the second positive electrode current collector.

[0293] The intermediate layer was prepared by coating an aluminum thin film with a composition containing a carbon conductive material (Danka black) and polyvinylidene fluoride (PVDF), and then drying it. The thickness of the intermediate layer, which was placed on one surface of the aluminum thin film, was approximately 1 μm.

[0294] A dry anode film, which is a self-supporting anode active material layer, was placed on the intermediate layer of the prepared first laminate, and the anode was manufactured by rolling.

[0295] (Manufacturing of positive electrodes) Composite positive electrode active material LiNi 0.91 Co 0.05 Al 0.04 A slurry was prepared by mixing a mixture of O2 (hereinafter referred to as NCA91), a carbon conductive agent (Denka Black), and polyvinylidene fluoride (PVDF) in a weight ratio of 96:2:2 with N-methylpyrrolidone (NMP) in an agate mortar.

[0296] The slurry was bar-coated onto an aluminum current collector to a thickness of 40 μm, dried at room temperature, dried again under vacuum conditions at 120°C, and then rolled to produce the positive electrode.

[0297] (Manufacturing of coin cells) Using the positive and negative electrodes manufactured as described above, coin cells were manufactured using a polypropylene separator (Celgard 3510) and a solution in which 1.15 M LiPF6 and 1.5 wt% vinylene carbonate (VC) were dissolved in EC (ethylene carbonate) + EMC (ethyl methyl carbonate) + DMC (dimethyl carbonate) (2:4:4 volume ratio) as electrolytes.

[0298] Example 2: Dry negative electrode film containing graphite, SCN, GB 0.5%, and binder. Graphite, the first negative electrode active material, the silicon composite structure (SCN) used in Production Example 4, the second negative electrode active material, polytetrafluoroethylene (PTFE) as a dry binder, and the composite (GB) prepared in Production Example 1 were added to a blade mixer in a weight ratio of 81.5:15:3:0.5. Primary dry mixing was then performed at 25°C at a speed of 1200 rpm for 10 minutes to prepare a first dry mixture in which the dry positive electrode active material, dry conductive material, and dry binder were uniformly mixed.

[0299] The dry anode film comprises a first composite anode active material having a structure in which a shell containing a composite and / or its milling result is coated on a graphite core, and a second composite anode active material having a structure in which a shell containing a composite and / or its milling result is coated on an SCN core.

[0300] Example 3 A coin cell was manufactured in the same manner as in Example 1, except that the negative electrode was manufactured by the following process.

[0301] (Manufacturing of negative electrodes) Graphite, the first negative electrode active material, the silicon composite structure (SCN) used in Production Example 4, the second negative electrode active material, polytetrafluoroethylene (PTFE) as a dry binder, and the composite (GB) prepared in Production Example 1 were added to a blade mixer in a weight ratio of 40.5:7.5:1:0.2. A primary dry mixing was then performed at 25°C at a speed of 1200 rpm for 10 minutes to prepare a first dry mixture in which the dry positive electrode active material and dry binder were uniformly mixed.

[0302] Next, to further promote the fiberization of the binder, the first mixture was further secondary-mixed at 25°C at a speed of 5000 rpm for 20 minutes to prepare the second mixture. No additional solvents were used in the preparation of the first and second mixtures.

[0303] The prepared second mixture was fed into an extruder and extruded to prepare the first dry anode film as a sheet-like self-standing film of the anode active material layer. The extrusion pressure was 50 MPa. The dry anode film contains a composite anode active material having a structure in which a shell containing the composite and / or its milling results is coated on a graphite core.

[0304] Separately, when producing the second dry mixture for forming the second dry anode film, the process was carried out in the same manner as described above, except that the weight ratio of the first anode active material, graphite, the second anode active material, the silicon composite structure (SCN) used in Production Example 4, and the dry binder, polytetrafluoroethylene (PTFE) and the composite (GB) prepared in Production Example 1, was changed to 40.5:7.5:2:0.3.

[0305] A first laminate was prepared in which a carbon layer was placed as an interlayer on one surface of a 12 μm thick copper thin film, and the interlayer was placed on one surface of the second positive electrode current collector.

[0306] The intermediate layer was prepared by coating an aluminum thin film with a composition containing a carbon conductive material (Danka black) and polyvinylidene fluoride (PVDF), and then drying it. The thickness of the intermediate layer, which was placed on one surface of the aluminum thin film, was approximately 1 μm.

[0307] A first dry anode film and a second dry anode film were sequentially placed on the intermediate layer of the prepared first laminate, and the resulting dry anode (copper thin film / intermediate layer (carbon layer) / first dry anode film / second dry anode film) was manufactured by rolling.

[0308] Example 4 A coin cell was manufactured in the same manner as in Example 2, except that the negative electrode shown in Figure 4C was manufactured by the following process.

[0309] (Manufacturing of dry anodes) Graphite, the silicon composite structure (SCN) used in Production Example 4 as the second negative electrode active material, polytetrafluoroethylene (PTFE) as a dry binder, and the composite (GB) prepared in Production Example 1 were added to a blade mixer in a weight ratio of 40.75:15:2:0.3. Primary dry mixing was then performed at 25°C at a speed of 1200 rpm for 10 minutes to prepare a first dry mixture in which the dry positive electrode active material and dry binder were uniformly mixed.

[0310] Next, to further promote the fiberization of the binder, the first mixture was further secondary-mixed at 25°C at a speed of 5000 rpm for 20 minutes to prepare the second mixture. No additional solvents were used in the preparation of the first and second mixtures.

[0311] The prepared second mixture was fed into an extruder and extruded to prepare the first dry anode film as a sheet-like self-standing film of the anode active material layer. The extrusion pressure was 50 MPa. The dry anode film contains a composite anode active material having a structure in which a shell containing the composite and / or its milling results is coated on a graphite core.

[0312] Separately, a second dry anode film was manufactured in the same manner as described above, except that the weight ratio of the first anode active material, graphite, the dry binder, polytetrafluoroethylene (PTFE), and the composite (GB) prepared in Manufacturing Example 1 was changed to 40.75:1:0.2 during the production of the first dry mixture.

[0313] A first laminate was prepared in which a carbon layer was placed as an interlayer on one surface of a 12 μm thick copper thin film, and the interlayer was placed on one surface of the second positive electrode current collector.

[0314] The intermediate layer was prepared by coating an aluminum thin film with a composition containing a carbon conductive material (Danka black) and polyvinylidene fluoride (PVDF), and then drying it. The thickness of the intermediate layer, which was placed on one surface of the aluminum thin film, was approximately 1 μm.

[0315] A first dry anode film and a second dry anode film were sequentially placed on the intermediate layer of the prepared first laminate, and the resulting dry anode (copper thin film / intermediate layer (carbon layer) / first dry anode film / second dry anode film) was manufactured by rolling.

[0316] Example 5 A coin cell was manufactured in the same manner as in Example 3, except that the negative electrode shown in Figure 4B was manufactured using the following process.

[0317] (Manufacturing of negative electrodes) Graphite, the first negative electrode active material, the silicon composite structure (SCN) used in Production Example 4, the second negative electrode active material, polytetrafluoroethylene (PTFE) as a dry binder, and the composite (GB) prepared in Production Example 1 were added to a blade mixer in a weight ratio of 40.5:7:1:0.2. A primary dry mixing was then performed at 25°C at a speed of 1200 rpm for 10 minutes to prepare a first dry mixture in which the dry positive electrode active material and dry binder were uniformly mixed.

[0318] Next, to further promote the fiberization of the binder, the first mixture was further secondary-mixed at 25°C at a speed of 5000 rpm for 20 minutes to prepare the second mixture. No additional solvents were used in the preparation of the first and second mixtures.

[0319] The prepared second mixture was fed into an extruder and extruded to prepare the first dry anode film as a sheet-like self-standing film of the anode active material layer. The extrusion pressure was 50 MPa. The dry anode film contains a composite anode active material having a structure in which a shell containing the composite and / or its milling results is coated on a graphite core.

[0320] Separately, when producing the second dry mixture for forming the second dry anode film, the process was carried out in the same manner as described above, except that the weight ratio of the first anode active material, graphite, the second anode active material, the silicon composite structure (SCN) used in Production Example 4, and the dry binder, polytetrafluoroethylene (PTFE) and the composite (GB) prepared in Production Example 1, was changed to 40.5:8:2:0.3.

[0321] A first laminate was prepared in which a carbon layer was placed as an interlayer on one surface of a 12 μm thick copper thin film, and the interlayer was placed on one surface of the second positive electrode current collector.

[0322] The intermediate layer was prepared by coating an aluminum thin film with a composition containing a carbon conductive material (Danka black) and polyvinylidene fluoride (PVDF), and then drying it. The thickness of the intermediate layer, which was placed on one surface of the aluminum thin film, was approximately 1 μm.

[0323] A first dry anode film and a second dry anode film were sequentially placed on the intermediate layer of the prepared first laminate, and the resulting dry anode (copper thin film / intermediate layer (carbon layer) / first dry anode film / second dry anode film) was manufactured by rolling.

[0324] Comparative Example 1: Manufacturing of a wet anode (Manufacturing of negative electrodes) The first negative electrode active material, graphite, the binder, polytetrafluoroethylene (PTFE), and the conductive material, the composite (GB) prepared in Production Example 1, were placed in a blade mixer in a weight ratio of 96.5:3:0.5. After mixing at 25°C at a speed of 1200 rpm for 10 minutes, water was added and mixed to obtain a negative electrode active material slurry.

[0325] After applying the aforementioned negative electrode active material slurry to copper foil, a film was formed using a doctor blade to achieve a coating thickness of 20 μm. This film was then vacuum-dried at 130°C for 3 hours, and finally rolled to produce the negative electrode.

[0326] Comparative Example 2: Manufacturing of a dry anode The dry anode was manufactured in the same manner as in Example 1, except that Denka Black was used instead of the composite material manufactured in Manufacturing Example 1 during the production of the first dry mixture.

[0327] Comparative Example 3: Manufacturing of a dry anode The dry anode was manufactured in the same manner as in Example 2, except that, during the production of the first dry mixture, only the silicon composite structure (SCN) used in Production Example 4 was used instead of the first anode active material, graphite, and the second anode active material, the silicon composite structure (SCN) used in Production Example 4.

[0328] Evaluation Example 1: Tensile Strength Evaluation For each of the dry anode films produced in Examples 1-4 and Comparative Examples 2-3, a specimen for tensile strength measurement using ASTMD638 (216 mm (Length) × 19 ± 0.5 mm (Width) × 3.18 ± 0.38 mm (Depth)) was prepared. Tensile strength tests were performed using the ASTMD638 method to measure the tensile strength. The measurement results are shown in Table 1 below. [Table 1]

[0329] As shown in Table 1, the dry anode films of Examples 1 to 5 exhibit improved mechanical strength compared to the dry anode films of Comparative Examples 1 to 3.

[0330] It was determined that the dry anodes of Examples 1 and 2 were superior to those of Comparative Examples 1 and 2 because each component was more uniformly distributed, the binder was even more uniformly distributed within the dry anode film, and the fibrous binder more effectively bound the composite cathode active material.

[0331] Evaluation Example 2: Evaluation of Combination Drug Resistance For each of the dry negative electrodes produced in Examples 1-5 and Comparative Examples 1-3, the composite resistance was measured at 25°C using an electrode resistance measurement system (Hioki, RM2610), and the measurement results are shown in Table 3 below.

[0332] Using an electrode resistance measurement system (Hioki, RM2610), the probe was positioned so that the negative electrode active material layer of the negative electrode faced the probe. A constant current was passed over the surface of the negative electrode active material layer, and the volume resistivity of the negative electrode active material layer and the interfacial resistance between the negative electrode active material layer and the negative electrode current collector were measured from the surface potential distribution. The volume resistivity of the negative electrode active material layer was considered as the composite resistance of the negative electrode active material layer.

[0333] Evaluation Example 3: Interfacial Resistance Evaluation For each of the dry negative electrodes manufactured in Examples 1-5 and Comparative Examples 1-3, the interfacial resistance was measured at 25°C using an electrode resistance measurement system (Hioki, RM2610), and the measurement results are shown in Table 2 below.

[0334] Using an electrode resistance measurement system (Hioki, RM2610), the probe was positioned on the negative electrode so that the negative electrode active material layer faced the probe. A constant current was passed through the surface of the negative electrode active material layer, and the volume resistivity of the negative electrode active material layer and the interfacial resistance between the negative electrode active material layer and the negative electrode current collector were measured from the surface potential distribution. [Table 2]

[0335] As shown in Table 2, the dry anodes of Examples 1 to 5 exhibited reduced compound resistance compared to the dry anodes of Comparative Examples 1 to 3.

[0336] It was determined that the dry anodes of Examples 1 to 5 exhibited improved electronic and / or ionic conductivity within the dry anode film due to the inclusion of a composite anode active material in which a shell containing a composite is uniformly arranged on the core.

[0337] It was determined that the electronic conductivity and / or ionic conductivity of the wet anode in Comparative Example 1 and the dry anodes in Comparative Examples 2 and 3 decreased because they did not contain the composite anode active material described above.

[0338] As shown in Table 2, the dry anodes of Examples 1 to 5 exhibited reduced interfacial resistance compared to the dry anodes of Comparative Examples 1 to 3.

[0339] Evaluation Example 4: Adhesion of the electrode plates Using an adhesive strength measuring instrument (UTM, Instron), each dry anode specimen manufactured in Examples 1-5 and Comparative Examples 1-3 was cut to 150 mm x 15 mm, attached to double-sided adhesive tape, and the force of detachment at 90° was measured. The results are shown in Table 3 below. [Table 3]

[0340] As shown in Table 3, the wet anode of Comparative Example 1 showed improved electrode plate adhesion compared to the dry anode films of Comparative Examples 2 and 3. However, the dry anode films of Examples 1 to 5 were found to have improved electrode plate adhesion compared to the wet anode of Comparative Example 1 and the dry anodes of Comparative Examples 2 and 3.

[0341] Evaluation Example 5: Evaluation of charge / discharge characteristics at room temperature (25°C) The lithium batteries manufactured in Examples 1-5 and Comparative Examples 1-3 were charged with a constant current of 0.1C rate at 25°C until the voltage reached 4.5V (vs.Li), and then cut off with a current of 0.02C rate while maintaining 4.5V in constant voltage mode. Subsequently, they were discharged with a constant current of 0.1C rate until the voltage reached 2.75V (vs.Li) (formation cycle).

[0342] A lithium battery that had undergone a chemical conversion cycle was charged with a constant current of 0.2C rate at 25°C until the voltage reached 4.5V (vs.Li). Then, while maintaining 4.5V in constant voltage mode, it was cut off with a current of 0.02C rate. Next, it was discharged with a constant current of 0.2C rate until the voltage reached 2.75V (vs.Li) (1st cycle). This cycle was repeated under the same conditions for 50 cycles (50 repetitions).

[0343] A 10-minute stop period was observed after each charge / discharge cycle in all charge / discharge cycles. Some of the results from the room-temperature charge / discharge experiments are shown in Table 4 below. Initial efficiency is defined by Equation 1 below, and capacity retention is defined by Equation 2 below. <Expression 1> Initial efficiency [%] = [Discharge capacity in the chemical cycle / Charge capacity in the chemical cycle] × 100 <Expression 2> Capacity retention rate [%] = [Discharge capacity in the 50th cycle / Discharge capacity in the 1st cycle] × 100 [Table 4]

[0344] As shown in Table 4, the lithium batteries of Examples 1 to 5 showed improved lifespan characteristics compared to the lithium batteries of Comparative Examples 1 and 2.

[0345] Such improved life characteristics were judged to be because the formation of the solid electrolyte membrane (SEI) on the surface and / or inside of the negative electrode active material was suppressed by the composite coating, and thereby the internal resistance of the lithium battery was suppressed.

[0346] Evaluation Example 6: XPS (X-ray photoelectron spectroscopy) spectrum evaluation During the manufacturing process of the composite manufactured in Production Example 1, XPS spectra were measured using Quantum 2000 (Physical Electronics) over time. XPS spectra of the C 1s orbital and Al 2p orbital for samples before temperature rise, after 1 minute, after 5 minutes, after 30 minutes, after 1 hour, and after 4 hours were measured respectively. At the initial stage of temperature rise, only a peak for the Al 2p orbital was shown, and no peak for the C 1s orbital was shown. After 30 minutes, a peak for the C 1s orbital was clearly shown, and the size of the peak for the Al 2p orbital decreased significantly.

[0347] After 30 minutes, a peak for the C 1s orbital due to C-C bonds and C=C bonds caused by the growth of graphene was clearly shown near 284.5 eV.

[0348] As the reaction time elapsed and the oxidation number of aluminum decreased, the peak position of the Al 2p orbital shifted to the side with a lower binding energy (binding energy, eV).

[0349] Therefore, as the reaction proceeded, graphene grew on the Al2O3 particles, and it was confirmed that Al2O x (0 < x < 3) was generated.

[0350] The average carbon and aluminum content was measured through XPS analysis of 10 regions of the composite sample produced in Production Example 1. The deviation of aluminum content in each region was calculated from the measurement results. The deviation of aluminum content is expressed as a percentage of the average value and is called uniformity. The percentage of the deviation of aluminum content relative to the average value, i.e., the uniformity of aluminum content, was 1%. Therefore, it was confirmed that alumina is uniformly distributed within the composite produced in Production Example 1. [Explanation of symbols]

[0351] 1 Lithium battery 2 negative electrode 3 Positive electrode 4 Separators 5 Battery case 6 Cap Assembly 7 Battery structure 8 Electrode Tabs 10 cores 20 shells 21. First Metal Oxides 22. First carbon-based materials 23 Second carbon-based materials 100 Dry negative electrode active material

Claims

1. The dry anode active material and the dry binder are included. The dry anode active material includes a composite anode active material comprising a core and a shell arranged along the surface of the core. The core comprises a carbon-based material; a mixture of a carbon-based material and a silicon-based active material; a composite of a carbon-based material and a silicon-based active material; or a combination thereof. The shell comprises a composite containing one or more first metal oxides and a first carbon-based material. The first metal oxide is arranged within the first carbon-based material matrix. The first metal oxide is chemical formula M ａ O ｂ A dry negative electrode film, represented as (0 < a ≤ 3, 0 < b < 4, and if a is 1, 2, or 3, then b is not an integer), wherein M is one or more metals selected from groups 2 to 16 of the periodic table.

2. The dry anode film according to claim 1, wherein the dry anode film has a multilayer structure of two or more layers.

3. The dry anode film includes a first dry anode film and a second dry anode film. The dry anode film according to claim 1, wherein the binder content and composite content of the first dry anode film are each greater than the binder content and composite content of the second dry anode film.

4. The dry anode film is a self-standing film, and the dry anode film is free of residual processing solvent. The dry anode film according to claim 1, wherein the tensile strength of the dry anode film before rolling is 450 kPa or more, and the tensile strength after rolling is 1000 kPa or more.

5. The dry anode film according to claim 1, wherein the content of the composite is 5% by weight or less based on the total weight of the dry anode film.

6. The metal contained in the first metal oxide is one or more metals selected from Al, Nb, Mg, Sc, Ti, Zr, V, W, Mn, Fe, Co, Pd, Cu, Ag, Zn, Sb, and Se. where the first metal oxide is Al ２ O ｚ (0 < z < 3), NbO ｘ (0 < x < 2.5), MgO ｘ (0 < x < 1), Sc ２ O ｚ (0 < z < 3), TiO ｙ (0 < y < 2), ZrO ｙ (0 < y < 2), V ２ O ｚ (0 < z < 3), WO ｙ (0 < y < 2), MnO ｙ (0 < y < 2), Fe ２ O ｚ (0 < z < 3), Co ３ O ｗ (0 < w < 4), PdO ｘ (0 < x < 1), CuO ｘ (0 < x < 1), AgO ｘ (0 < x < 1), ZnO ｘ (0 < x < 1), Sb ２ O ｚ (0 < z < 3), and SeO ｙ (0 < y < 2), and is one or more selected therefrom, the dry negative electrode film according to claim 1.

7. The shell further comprises a second metal oxide, The second metal oxide is chemical formula M ａ O ｃ It is expressed as (0 < a ≤ 3, 0 < c ≤ 4, if a is 1, 2, or 3, then c is an integer), The second metal oxide contains the same metal as the first metal oxide, The ratio of a to c in the second metal oxide, c / a, is even larger than the ratio of a to b in the first metal oxide, b / a. The dry anode film according to claim 1, wherein the second metal oxide is disposed within the first carbon-based material matrix.

8. The second metal oxide is Al ２ O ３ NbO, NbO ２ , Nb ２ O ５ MgO, Sc ２ O ３ , TiO ２ , ZrO ２ , V ２ O ３ WO ２ MnO ２ Fe ２ O ３ Co ３ O ４ , PdO, CuO, AgO, ZnO, Sb ２ O ３ , and SeO ２ Selected from among, The dry anode film according to claim 7, wherein the first metal oxide is a reduction product of the second metal oxide.

9. The carbon-based material is crystalline carbon, amorphous carbon, or a combination thereof. The crystalline carbon is one or more selected from the group consisting of natural graphite, artificial graphite, graphene, fullerene, and carbon nanotubes. The dry anode film according to claim 1, wherein the amorphous carbon is one or more selected from the group consisting of pitch carbon, soft carbon, hard carbon, mesophase pitch carbide, calcined coke, and carbon fibers.

10. The silicon-based active material is a Si alloy, a silicon-containing structure, a silicon-containing compound, or a combination thereof. The silicon-containing compound is SiO ２ , SiOx (0 < x < 2), SiC, or a combination thereof, The dry anode film according to claim 1, wherein the silicon-containing structure includes a silicon composite structure.

11. The silicon-based active material includes a silicon-based composite structure, The dry anode film according to claim 10, wherein the silicon-based composite structure includes a silicon-carbon composite comprising silicon particles and a first carbon-based material, a silicon-carbon composite comprising a core in which silicon particles and a second carbon-based material are mixed and a third carbon-based material surrounding the core, or a combination thereof.

12. The dry binder includes a fibrous binder. The dry binder includes a fluorine-based binder, The glass transition temperature (Tg) of the dry binder is 15 to 100°C. The dry anode film according to claim 1, wherein the dry binder content is 0.1 to 5 wt% of the total weight of the dry anode film.

13. The dry negative electrode film further comprises a dry conductive material, The dry conductive material includes a carbon-based conductive material, The carbon-based conductive material includes a fibrous carbon-based material with an aspect ratio of 10 or more, a particulate carbon-based material with an aspect ratio of less than 10, or a combination thereof. The dry anode film according to claim 1, wherein the dry conductive material content is 0.1 to 5 wt% of the total weight of the dry anode film.

14. Negative electrode current collector and A dry negative electrode comprising a dry negative electrode film according to any one of claims 1 to 13, disposed on one or both sides of the negative electrode current collector.

15. The negative electrode current collector comprises a base material; and an intermediate layer disposed between the base material and the dry negative electrode film. The dry anode according to claim 14, wherein the intermediate layer includes a carbon-based conductive material.

16. The dry negative electrode film includes a first dry negative electrode film positioned adjacent to the negative electrode current collector and a second dry negative electrode film positioned above the first dry negative electrode film. The dry anode according to claim 14, wherein the composite content and binder content of the first dry anode film are greater than, respectively, the composite content and binder content of the second dry anode film.

17. The first dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry composite anode active material. The silicon-based active material includes a silicon composite structure, The second dry anode film includes a carbon-based material as the core of the dry composite anode active material. The dry anode according to claim 16, wherein the binder content of the first dry anode film is the same as or greater than the binder content of the second dry anode film, and the composite content of the first dry anode film is the same as or greater than the composite content of the second dry anode film.

18. The dry negative electrode film includes a first dry negative electrode film arranged adjacent to the negative electrode current collector and a second dry negative electrode film arranged on the first dry negative electrode film. The first dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry composite anode active material. The second dry anode film includes a carbon-based material and a silicon-based active material as the core of the dry anode active material. The silicon-based active material of the first dry anode film and the second dry anode film includes a silicon composite structure. The binder content of the first dry anode film is the same as, or significantly greater than, the binder content of the second dry anode film. The content of the composite (GB) in the first dry anode film is the same as, or significantly greater than, the content of the composite in the second dry anode film. The dry anode according to claim 14, wherein the content of carbon-based material in the first dry anode film is the same as or greater than the content of carbon-based material in the second dry anode film, and the content of silicon-based active material in the first dry anode film is the same as or greater than the content of silicon-based active material in the second dry anode film.

19. It includes a positive electrode, a negative electrode, and an electrolyte placed between the positive and negative electrodes. The negative electrode is the dry negative electrode described in claim 15. The electrolyte includes a liquid electrolyte, a solid electrolyte, a gel electrolyte, or a combination thereof. A lithium battery in which the solid electrolyte includes an oxide-based solid electrolyte, a sulfide-based solid electrolyte, a polymer solid electrolyte, or a combination thereof.

20. The positive electrode includes a positive electrode current collector, and the negative electrode includes a negative electrode current collector. The positive electrode current collector and the negative electrode current collector each include a base film and a metal layer disposed on one or both sides of the base film. The base film comprises a polymer, and the polymer comprises polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI), or a combination thereof. The lithium battery according to claim 19, wherein the metal layer comprises indium (In), copper (Cu), magnesium (Mg), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof.

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