Dry electrode, manufacturing method thereof, and lithium secondary battery comprising same

Abstract

The present invention relates to a dry electrode comprising: a current collector; and an electrode composite film disposed on the current collector, wherein the electrode composite film includes an electrode active material and a fiberizable binder, the ratio (IB / IA) of C3H7 + peak intensity (IB) to C2H3O+ peak intensity (IA) measured for the surface of the current collector by time-of-flight secondary ion mass spectrometry (ToF-SIMS) is 1.3 or less, and the ratio of the carbon content at the interface of the current collector to the carbon content inside the electrode composite film as measured by scanning electron microscope-energy dispersive X-ray spectroscopy is at least 1.08.

Description

Dry electrode, method for manufacturing same, and lithium secondary battery comprising same Cross-citation with related applications This application claims the benefit of priority to Korean Patent Application No. 10-2023-0189907, filed December 22, 2023, and Korean Patent Application No. 10-2023-0189908, filed December 22, 2023, the entire contents of which are incorporated herein by reference. Technical field The present invention relates to a dry electrode, a method for manufacturing the same, and a lithium secondary battery including the same. Secondary batteries are used in small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and e-bikes, as well as in large products requiring high output such as electric vehicles and hybrid vehicles, as well as in power storage devices that store surplus generated power or renewable energy and as backup power storage devices. Typically, secondary batteries are manufactured by applying electrode active material slurry to a positive electrode collector and a negative electrode collector to form an electrode active material layer, then drying and rolling the electrodes to manufacture the positive and negative electrodes, and laminating them on both sides of a separator to form an electrode assembly of a predetermined shape, then housing the electrode assembly in a battery case, injecting electrolyte, and sealing the assembly. Meanwhile, during the drying process of the electrode active material slurry, the solvent contained in the slurry may evaporate, causing defects such as pinholes or cracks in the electrode active material layer formed on the current collector. In addition, during the drying process, the inside and outside of the electrode active material slurry are not uniformly dried, so there is a concern that the quality of the electrode may deteriorate due to the powder floating phenomenon caused by the difference in the solvent evaporation rate, that is, the powder in the area that dries first rises and forms a gap with the area that dries relatively later. To solve the above problem, drying devices capable of controlling the evaporation rate of the solvent so that the inside and outside of the electrode active material slurry can be uniformly dried are being considered, but these drying devices are very expensive and require considerable cost and time to operate, which is disadvantageous in terms of manufacturing process. On the other hand, the solvent included in the conventional electrode active material slurry is N-methyl-2-pyrrolidone (NMP), which has a high boiling point, so it requires high heat energy and a very long drying process to dry, which is very disadvantageous for mass production. In addition, N-methyl-2-pyrrolidone (NMP) is a toxic substance and is harmful to living organisms, so it is not environmentally friendly. Accordingly, research on dry electrodes that manufacture electrodes without using a solvent has been actively conducted recently. The dry electrode is generally manufactured by laminating a free-standing type electrode composite film manufactured in the form of a sheet, which includes an electrode active material, a binder, a conductive material, etc., onto a current collector. The electrode composite film includes a process of first mixing an electrode active material, a carbon material as a conductive material, and a fiberizable binder together using a blender, etc., and then fiberizing the binder by applying a shear force through a process such as jet milling or kneading, and then calendering the obtained mixture into a film form to manufacture a free-standing film. Meanwhile, conventional dry electrodes are manufactured by laminating an electrode composite film on a current collector, or by forming a conductive primer layer on a current collector to prevent peeling between the electrode composite film and the current collector, and then laminating the electrode composite film. However, there is a problem in that the current collector and the electrode composite film are peeled off due to rolling oil remaining on the current collector surface, or the conductive primer layer is not formed evenly, causing peeling of the conductive primer layer. To solve these problems, a process of washing the rolling oil remaining on the collector with an alkaline solution has been proposed; however, there is a problem in that the unit cost of the process is high or an additional alkaline washing process needs to be performed, which reduces the processability. Therefore, in order to prevent deterioration of cell performance due to delamination between the current collector and the electrode composite film, or between the current collector and the conductive primer layer, a dry electrode having excellent adhesion between the current collector and the electrode composite film, or between the current collector and the conductive primer layer, and excellent coating properties of the conductive primer layer is required. The object of the present invention is to solve the above problems, and to provide a dry electrode having excellent adhesion between a current collector and a conductive primer layer or between a current collector and an electrode composite film and excellent coating properties of a conductive primer layer, a method for manufacturing the same, and a lithium secondary battery including the same. [1] According to one embodiment of the present invention, a current collector is provided, and an electrode composite film is disposed on the current collector, wherein the electrode composite film includes an electrode active material and a fiberizable binder, and C2H3O measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) with respect to the surface of the current collector. + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) is 1.3 or less, and the ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film, as measured by a scanning electron microscope-energy dispersive X-ray spectroscopy, is 1.08 or more. [2] In the above [1], the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the surface of the collector T ) for C3H7 + Peak intensity (I B ) Rain (I B / I T ) is 230x10 -5 It could be as follows. [3] In the above [1] and / or [2], the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the surface of the collector T ) for C2H3O + Peak intensity (I A ) Rain (I A / I T ) is 1000x10 -5 It could be as follows. [4] In any one or more of the above [1] to [3], the entire body may include aluminum. [5] In at least one of the above [1] to [4], the tensile strength of the entire body is 5 kgf / mm. 2 It could be strange. [6] In any one or more of the above [1] to [5], the water contact angle of the surface of the collector may be 10° to 100°. [7] In any one or more of the above [1] to [6], rolling oil may be included on the surface of the entire body. [8] According to one embodiment of the present invention, a method for manufacturing a dry electrode is provided, comprising: a step of treating the surface of a current collector with atmospheric plasma; and a step of forming a conductive primer layer on the current collector; wherein a loading speed of the current collector in the atmospheric plasma treatment is 1 m / min to 100 m / min. [9] In the above [8], the atmospheric pressure plasma treatment may be performed at an injection flow rate of an inert gas of 500 L / min to 1000 L / min and an injection flow rate of an oxygen-containing gas of 0.1 L / min to 10 L / min.

[0010] In the above [8] and / or [9], the atmospheric pressure plasma treatment may have a ratio of the injection flow rate of the inert gas to the injection flow rate of the oxygen-containing gas of 50 to 10,000.

[0011] In any one or more of the above [8] to

[0010] , the atmospheric pressure plasma treatment may have a voltage of 10 kV to 20 kV.

[0012] In any one or more of the above [8] to

[0011] , the atmospheric pressure plasma treatment may have a power of 3 kW to 5 kW.

[0013] In any one or more of the above [8] to

[0012] , the atmospheric pressure plasma treatment may be performed with the collector and the plasma nozzle separated by 0.01 mm to 3.00 mm.

[0014] According to one embodiment of the present invention, a lithium secondary battery is provided including at least one dry electrode among [1] to [7]. The dry electrode according to the present invention is characterized by excellent adhesion between a current collector and an electrode composite film or a current collector and a conductive primer layer, and excellent coatability because the conductive primer layer can be evenly coated on the current collector. Accordingly, the problem of peeling between the current collector and the electrode composite film or the current collector and the conductive primer layer can be prevented, and the excellent coatability of the conductive primer layer can prevent the phenomenon of the conductive primer layer lifting, thereby improving the resistance characteristics, rapid charge / discharge characteristics, and life characteristics of the battery. The drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the contents of the invention described above, serve to better understand the technical idea of ​​the present invention, so the present invention is not limited to the matters described in such drawings. Meanwhile, the shape, size, scale or ratio of elements in the drawings included in this specification may be exaggerated to emphasize a clearer explanation. Figure 1 is a drawing showing an area mapped when measuring the ratio of the carbon content at the collector interface to the carbon content inside the electrode composite film using a scanning electron microscope-energy dispersive X-ray spectroscopy. Figure 2 is a drawing showing that the conductive primer layer formed on a current collector manufactured in Example 4 is not peeled off according to Experimental Example 2. Figure 3 is a drawing showing that the conductive primer layer is peeled off according to Experimental Example 2 for a current collector formed with a conductive primer layer manufactured in Comparative Example 1. Figure 4 is a drawing showing that the conductive primer layer is peeled off according to Experimental Example 2 for a current collector formed with a conductive primer layer manufactured in Comparative Example 2. Figure 5 is a drawing showing that no lifting occurs when evaluating the electrode appearance according to Experimental Example 2 for the dry electrode manufactured in Example 4. Figure 6 is a drawing showing the lifting when evaluating the electrode appearance according to Experimental Example 2 for the dry electrode manufactured in Comparative Example 1. Figure 7 is a drawing showing the lifting when evaluating the electrode appearance according to Experimental Example 2 for the dry electrode manufactured in Comparative Example 2. Hereinafter, the present invention will be described more preferably. The terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as having meanings and concepts that conform to the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concept of the term in order to explain his or her own invention in the best manner. In the present invention, the MD direction (Machine Direction) means the longitudinal direction of the current collector or electrode composite film, and the TD direction (Transverse Direction) means the width direction of the current collector or electrode composite film. In this specification, the "composite composition" means a mixture including an electrode active material and a binder and optionally a conductive material, which is physically mixed to form a uniform dispersion phase, and may be a powder mixture as a product of a mixing process (mixing process) according to this specification, and may be one in which substantially no solvent is involved. Here, substantially no solvent is involved means that no solvent is added or only a very small amount of solvent is added when mixing the composite composition. In this specification, the “mixed aggregate” refers to a mixture of powders that is converted into a dough-like aggregate by binding or connecting each other when the binder is fiberized by applying a shear force to the composite composition, and is a product of the kneading process (kneading process) according to this specification, which may have a solids content substantially close to 100% and may contain a small amount of solvent in some cases. In this specification, “electrode powder” may mean a powder-type electrode material that is a material in which the mixed aggregate is pulverized to form smaller particles and thus forms a powder, and includes an electrode active material, a binder, and optionally a conductive material. In this specification, the "electrode composite film" may mean an electrode composite layer manufactured in the form of a free-standing single sheet using an "electrode composite" including an electrode active material, a conductive material, and a binder without involving a solvent, or in a state of being laminated on a current collector. The term "free-standing" in this specification means that it can maintain a single form without relying on other members and can be moved or handled by itself. The electrode composite film may be formed by compressing an electrode powder as described below. For example, it may have a shape in which an electrode powder is integrated by compression to form a layered structure. In this specification, the term "powder-sheeting film" means a film formed in a sheet shape through a powder-sheeting process in which electrode powder first passes through a rolling roll in a roll-to-roll process (e.g., a calendaring process) and before passing through the last rolling roll in the roll-to-roll process. The film may be a self-supporting sheet, but may have relatively weak self-supporting force. Here, the "powder-sheeting" means that the electrode powder is formed into a self-supporting sheet shape by a rolling roll in the roll-to-roll process, and "sheeting" is a process performed in the process in which the powder-sheeting film is manufactured into an electrode composite film, and may mean a process of roll-rolling the powder-sheeting film. In this specification, "Volume cumulative average particle diameter D 50 "In the particle size distribution curve, it means the particle size corresponding to 50% of the volume accumulation amount. The above D 50 For example, it can be measured using the laser diffraction method. The laser diffraction method can generally measure particle diameters from the submicron range to several mm, and can obtain results with high reproducibility and high resolution. In this specification, the "average particle diameter" means an arithmetic average value calculated by measuring the particle diameters of at least 30 particles observed in a scanning electron microscope image when observed at a field of view of 5,000 times to 20,000 times using a scanning electron microscope. In this case, the particle diameter means the longest axis diameter of the particle. The "volume cumulative average particle diameter D 50 " and "average particle size" have different measurement methods, but their values ​​can be derived similarly, and the volume-cumulative average particle size D measured in the powder state 50 The average particle size observed in the scanning electron microscope image of the electrode after the powder is manufactured into the electrode can have a value similar to the error range level. In this specification, the porosity can be calculated by the following mathematical formula A. [Mathematical Formula A] Porosity (%) = {1-(electrode density / true density)} × 100 In the above mathematical expression A, the true density is a calculated density derived from the density and mass ratio of each component material forming the powder-sheeting film or electrode composite film under the assumption that no pores are included, and the electrode density is a measured density of the powder-sheeting film or electrode composite film measured by sampling the powder-sheeting film or electrode composite film to a certain size. The present inventors have conducted continuous research to realize excellent adhesion between a current collector and an electrode composite film or between a current collector and a conductive primer layer and excellent coating properties of a conductive primer layer. As a result, the inventors have found that C2H3O is measured on the surface of a current collector by time-of-flight secondary ion mass spectrometry (ToF-SIMS). + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) and a scanning electron microscope-energy dispersive X-ray spectroscopy, the ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film satisfies a certain condition, and the adhesion between the current collector and the conductive primer layer and the coatability of the conductive primer layer are excellent, so that the electrochemical characteristics of the battery can be improved, thereby completing the present invention. Dry electrode A dry electrode according to the present invention comprises: a current collector; and an electrode composite film disposed on the current collector; wherein the electrode composite film comprises an electrode active material and a fiberizable binder, and C2H3O measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) with respect to the surface of the current collector + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) is 1.3 or less, and the ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film measured by a scanning electron microscope-energy dispersive X-ray spectroscopy is 1.08 or more. Conventionally, dry electrodes are manufactured by laminating an electrode composite film on a current collector, or by forming a conductive primer layer on a current collector to prevent peeling between the electrode composite film and the current collector, and then laminating the electrode composite film. At this time, since the current collector is typically a high-strength foil having a thickness on the order of micrometers, a large amount of rolling oil may remain on the current collector in order to manufacture it. However, if a large amount of rolling oil remains on the current collector, a problem may occur in which peeling occurs between the current collector and the electrode composite film due to the remaining rolling oil, or the conductive primer layer may not be formed evenly, causing the conductive primer layer to lift off. Accordingly, the present invention aims to improve the adhesion between a current collector and an electrode composite film or between a current collector and a conductive primer layer, and the coating property of the conductive primer layer, by performing plasma treatment satisfying specific conditions on the current collector, thereby changing the component of the rolling oil remaining on the current collector. According to one embodiment of the present invention, C2H3O measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) on the surface of the entire collector + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) may be less than 1.3. The above measured C2H3O + Peak intensity (I A ) may be a factor indicating the amount of organic matter of the CHO series present on the entire body, and the measured C3H7 + Peak intensity (I B ) may be a factor indicating the amount of CH series organic matter present on the collector. At this time, the CHO series organic matter is a hydrophilic substance, and the higher the amount, the better the coating and adhesive properties may be, but it may act as a factor that maximizes the interfacial resistance. In addition, the CH series organic matter is a hydrophobic substance, and the higher the amount, the lower the coating and adhesive properties may be. Therefore, the C2H3O + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) must be controlled within an appropriate range to achieve excellent coating properties and adhesion while maintaining low resistance. Preferably, C2H3O measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) on the surface of the entire collector + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A) may be 0.01 or more, 0.05 or more, 0.1 or more, 0.15 or more, 0.20 or more, or 0.25 or more, and may be 1.3 or less, 1.2 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, or 0.45 or less, and more preferably 0.25 to 0.45. The above C2H3O + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) Rain (I B / I A ) exceeds 1.3, since the component of the rolling oil formed on the surface of the current collector is not sufficiently changed, the surface energy of the current collector does not increase, so the adhesive strength between the conductive primer layer or the electrode composite film and the current collector is reduced, and a uniform or highly durable conductive primer layer is not formed when the conductive primer layer is formed on the current collector. For example, since the surface energy of the surface of the current collector is not uniform, a region with high or low adhesive strength locally occurs, so a region where the conductive primer layer is not formed evenly locally may occur, and the conductive primer layer may be lifted off. Therefore, when the above range is satisfied, the adhesiveness between the current collector and the conductive primer layer or the electrode composite film is excellent, and a uniform or highly durable conductive primer layer can be formed on the current collector, so that the resistance characteristics, rapid charge / discharge characteristics, and life characteristics of the battery can be improved. According to one embodiment of the present invention, the dry electrode may have a ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film, as measured by a Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy, of 1.08 or more. One feature of the present invention is to improve the adhesive strength at the current collector interface and the electrode composite film interface in contact with the current collector interface, and to prevent the lifting phenomenon of the conductive primer layer. Therefore, by satisfying the ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film, as measured by the above-described measuring method, the bonding strength between the current collector and the electrode composite film can be increased, while also implementing excellent resistance characteristics. Therefore, when the ratio of the carbon content at the collector interface to the carbon content inside the electrode composite film as measured by the Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy is less than 1.08, a problem of reduced adhesion may occur. Preferably, the ratio of the carbon content at the collector interface to the carbon content inside the electrode composite film as measured by the Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy may be 1.08 to 2.21. The intensity of the carbon distribution on the electrode cross-section measured by the above-mentioned Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy is not limited as long as it is measured by a measuring device commonly used in the art, but can be measured using, for example, JSM-IT800 (JEOL Corporation). At this time, the ratio of the carbon content at the collector interface to the carbon content inside the electrode composite film measured by the scanning electron microscope-energy dispersive X-ray spectrometer can be measured under the conditions of an acceleration voltage of 5 kV, an incident current (probe current) of 2.3 nA, and a working distance of 10 mm. In the case of the carbon content of the current collector interface, the carbon content (weight %) can be measured by performing mapping 10 times in a rectangular shape having a size of 2.0 μm x 1.5 μm centered on the current collector interface, and the average value can be obtained. In the case of the carbon content inside the electrode composite film, the carbon content (weight %) can be measured by performing mapping 10 times so that only the inside of the electrode composite film is included in the rectangular shape having a size of 2.0 μm x 1.5 μm, and the average value can be obtained. The total count measured at each time of mapping can be 35,000 cps. For example, referring to FIG. 1, as in the dotted rectangle, mapping is performed 10 times in a rectangular shape having a size of 2.0 μm x 1.5 μm centered on the current collector interface, the carbon content (in weight %) is measured and an average value is obtained, which can be evaluated as the carbon content of the current collector interface, and as in the solid rectangle, mapping is performed 10 times so that only the inside of the electrode composite film is included in the rectangular shape having a size of 2.0 μm x 1.5 μm, the carbon content (in weight %) is measured and an average value is obtained, which can be evaluated as the carbon content inside the electrode composite film, and the ratio of the carbon content of the current collector interface to the evaluated carbon content inside the electrode composite film can be derived. According to one embodiment of the present invention, the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the surface of the collector T ) for C3H7 + Peak intensity (I B ) Rain (I B / I T ) is 230x10 -5 It can be less than or equal to 1×10, preferably -5 Ideal, 10x10 -5 Ideal, 20x10 -5 Ideal, 30x10 -5 Ideal, 40x10 -5 Ideal, 50x10 -5 Ideal, 60x10 -5 Ideal, 70x10 -5 Ideal, 72x10 -5 Above, 74x10 -5 Ideal or 76x10 -5 It can be ideal, 200x10 -5 Below, 150x10 -5 Below, 100x10 -5 Below, 90x10 -5 Below, 88x10 -5 Below, 86x10 -5 Below, 84x10 -5 Below, 82x10 -5 Below or 81x10 -5 It can be less than or equal to 76×10, more preferably -5 Inside 81x10 -5 When the above range is satisfied, the surface energy of the current collector can be increased because there is less reactive organic matter on the current collector, so that the adhesion between the current collector and the conductive primer layer or the electrode composite film can be excellent, and a uniform or highly durable conductive primer layer can be formed on the current collector. According to one embodiment of the present invention, the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the surface of the collector T ) for C2H3O + Peak intensity (I A ) Rain (I A / I T ) is 1000x10 -5 It can be less than or equal to 1×10, preferably -5 Ideal, 10x10 -5 Ideal, 20x10 -5 Ideal, 40x10 -5 Ideal, 60x10 -5 Ideal, 80x10 -5 Ideal, 100x10 -5 Ideal, 120x10 -5 Ideal, 140x10 -5 Ideal, 160x10 -5 Ideal, 180x10 -5 Ideal or 184x10 -5 It could be ideal, 900x10 -5 Below, 800x10 -5 Below, 700x10 -5 Below, 600x10 -5 Below, 500x10 -5 Below, 400x10 -5 Below, 350x10 -5 Below, 320x10 -5 Below, 310x10 -5 Below or 309x10 -5 It may be less than or equal to 184x10, more preferably -5 Inside 309x10 -5 When the above range is satisfied, the surface energy of the current collector can be increased because there is less reactive organic matter on the current collector, so that the adhesion between the current collector and the conductive primer layer or the electrode composite film can be excellent, and a uniform or highly durable conductive primer layer can be formed on the current collector, and low interfacial resistance can be implemented. According to one embodiment of the present invention, the time-of-flight secondary ion mass spectrometry (ToF-SIMS) can be performed using a commonly used device, and preferably, it can be performed under specific conditions using TOF-SIMS 5 of Ion-TOF Co., Ltd. For example, it is performed in positive mode, the measurement mass range is 1u to 873u, the type of primary ion (source ion) is Bi3, and the dose of primary ion is 3.81×10 8 ions / cm 2 , the voltage can be performed under the conditions of 30 KeV, detection time of 100 seconds, and FOV (field of view) of 100㎛×100㎛. Next, we will describe the entire house in detail. When the above dry electrode is a positive electrode, the current collector may be any conductive material that does not cause a chemical change in the battery, and is not particularly limited. For example, the current collector may be stainless steel, aluminum, nickel, titanium, calcined carbon, or aluminum or stainless steel surface-treated with carbon, nickel, titanium, silver, etc. When the above dry electrode is a cathode, the current collector is not particularly limited as long as it has high conductivity without causing changes in the battery, and for example, copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., an aluminum-cadmium alloy, etc. can be used. In detail, the current collector may include aluminum, and more specifically, may be alloy number A1100 aluminum. When the current collector is aluminum or alloy number A1100 aluminum, the occurrence of current collector breakage due to strong plasma treatment can be prevented, and the problem of reduced adhesive strength due to residual rolling oil can be improved. According to one embodiment of the present invention, the thickness of the current collector may be 5 ㎛ to 30 ㎛, preferably 8 ㎛ to 20 ㎛, and more preferably 10 ㎛ to 15 ㎛. When the above range is satisfied, it is preferable in that defects such as pinholes do not occur in the current collector, thereby preventing a short circuit, and the thickness is not excessively thick, thereby increasing the energy density. In addition, fine unevenness may be formed on the surface of the current collector to increase the adhesive strength of the electrode composite film. According to one embodiment of the present invention, the tensile strength of the entire body is 5 kgf / mm. 2 Ideally, 6kgf / mm 2 Ideally, 7kgf / mm 2 It can be ideal. If the above range is satisfied, even if the thickness of the current collector is thin, it may have high strength, so that fracture may not occur easily, and it may withstand impact due to strong plasma treatment. In addition, in the case of a high-strength, high-rigidity current collector, unlike a general current collector substrate, a large amount of rolling oil may be used to manufacture the current collector. Therefore, the coating property and adhesive strength improvement effects due to plasma treatment may be more excellent. According to one embodiment of the present invention, the water contact angle of the current collector surface may be 10° to 100°, preferably 10° to 80°, and more preferably 10° to 70°. When the above range is satisfied, the surface energy of the current collector may be excellent while the process cost and process difficulty are not excessive, so that the adhesion between the current collector and the conductive primer layer or the current collector and the electrode composite film may be excellent. The above water contact angle can be measured by a conventional method in the art, for example, it can be measured by the tangent angle method by dropping a 3 μl drop at a speed of 3 μl / s using DSA100 from KRUSS. Next, the conductive primer layer is described. According to one embodiment of the present invention, a conductive primer layer may be included between the current collector and the electrode composite film. The current collector may be formed by coating a conductive primer entirely or partially on the surface to lower resistance and improve adhesion, thereby forming a conductive primer layer. Here, the conductive primer layer may include a conductive material for the primer layer and a binder for the primer layer, and the conductive material for the primer layer is not limited as long as it is a conductive material, but may be, for example, a carbon-based material. The binder for the primer layer may include a fluorine-based (including PVDF and PVDF copolymer), an acrylic-based binder, and an aqueous binder that can be dissolved in a solvent. According to one embodiment of the present invention, the conductive primer layer may include at least one selected from the group consisting of carbon black, graphite, and carbon nanotubes, preferably at least one selected from the group consisting of carbon black and graphite, and more preferably carbon black. When the above conditions are satisfied, excellent resistance characteristics can be implemented, and the effect of the current collector according to the present invention can be excellently expressed. According to one embodiment of the present invention, the conductive primer layer may include at least one selected from the group consisting of polyvinylidene fluoride (PVdF), carboxymethyl cellulose (CMC), polyethylene (PE), polypropylene (PP), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), and polymethyl methacrylate (PMMA). When the above conditions are satisfied, excellent adhesive properties can be implemented, and the effect of the current collector according to the present invention can be excellently expressed. According to one embodiment of the present invention, the conductive primer layer may contain the conductive material for the primer layer and the binder for the primer layer in a weight ratio of 0.1:1.0 to 8.0:1.0, preferably in a weight ratio of 0.2:1.0 to 5.0:1.0, and more preferably in a weight ratio of 0.4:1.0 to 3.0:1.0. When the above conditions are satisfied, excellent resistance and adhesion properties can be implemented, and the effect of the current collector according to the present invention can be excellently expressed. According to one embodiment of the present invention, the thickness of the conductive primer layer may be 5 ㎛ or less, preferably 5 ㎛ or less, 4 ㎛ or less, 3 ㎛ or less, 2 ㎛ or less, or 1 ㎛ or less, and may be 0.01 ㎛ or more, 0.1 ㎛ or more, or 0.2 ㎛ or more, and more preferably 0.2 ㎛ to 1 ㎛. When the above range is satisfied, it may be preferable in terms of improving the adhesive strength while reducing the side reaction with the electrolyte and the resistance. Next, the electrode composite film is described in detail. According to one embodiment of the present invention, the electrode composite film may include an electrode active material and a fiberizable binder, and preferably, the electrode composite film may include an electrode active material, a conductive material, and a fiberizable binder. There is no particular limitation on the above electrode active material as long as it is a commonly used electrode active material. For example, the above electrode active material may be a positive electrode active material or a negative electrode active material. The above cathode active material is a compound capable of reversible intercalation and deintercalation of lithium, and may preferably include a lithium metal oxide containing lithium and one or more metals such as cobalt, manganese, nickel or aluminum. More preferably, the lithium metal oxide is a lithium-manganese oxide (e.g., LiMnO2, LiMn2O4, etc.), a lithium-cobalt oxide (e.g., LiCoO2, etc.), a lithium-nickel oxide (e.g., LiNiO2, etc.), a lithium-nickel-manganese oxide (e.g., LiNi 1-Y Mn Y O2(here, 0 <Y<1), LiMn 2-Z Ni Z O4 (wherein, 0<Z<2) etc.), lithium-nickel-cobalt oxides (e.g., LiNi 1-Y1 Co Y1 O2(here, 0 <Y1<1) 등), 리튬-망간-코발트계 산화물(예를 들면, LiCo 1-Y2 MnY2 O2(here, 0 <Y2<1), LiMn 2-Z1 Co Z1 O4 (wherein, 0<Z1<2) etc.), lithium-nickel-manganese-cobalt oxides (e.g., Li(Ni p Co q Mn r )O2(where, 0<p<1, 0<q<1, 0<r<1, p+q+r=1) or Li(Ni p1 Co q1 Mn r1 )O4 (wherein, 0<p1<2, 0<q1<2, 0<r1<2, p1+q1+r1=2) etc.), or lithium-nickel-cobalt-transition metal (M) oxide (e.g., Li(Ni p2 Co q2 Mn r2 M s2 )O2 (wherein, M is selected from the group consisting of Al, Fe, V, Cr, Ti, Ta, Mg and Mo, and p2, q2, r2 and s2 are atomic fractions of independent elements, respectively, 0<p2<1, 0<q2<1, 0<r2<1, 0<s2<1, p2+q2+r2+s2=1), etc.), lithium iron phosphate (e.g., Li 1+a Fe 1-x M x (PO 4-b )X b (Here, M is at least one selected from Al, Mg, and Ti, X is at least one selected from F, S, and N, and -0.5≤a≤0.5, 0≤x≤0.5, 0≤b≤0.1) and the like, and one or more compounds among these may be included. Among these, the lithium metal oxides are LiCoO2, LiMnO2, LiNiO2, lithium nickel manganese cobalt oxide (e.g., Li(Ni)) in that they can improve the capacity characteristics and stability of the battery. 1 / 3 Mn 1 / 3 Co 1 / 3 )O2, Li(Ni 0.6 Mn 0.2 Co 0.2 )O2, Li(Ni) 0.5 Mn 0.3 Co 0.2 )O2, Li(Ni 0.7 Mn 0.15 Co 0.15 )O2 and Li(Ni 0.8 Mn 0.1 Co 0.1 )O2, etc.), lithium nickel cobalt aluminum oxide (e.g., Li(Ni 0.8 Co 0.15 Al 0.05 )O2, etc.), or lithium nickel manganese cobalt aluminum oxide (e.g. Li(Ni 0.86 Co 0.05 Mn 0.07 Al 0.02 )O2), lithium iron phosphate (e.g., LiFePO4), etc., and one or a mixture of two or more of these may be used. For example, the electrode active material may include a phosphorus oxide represented by the following chemical formula 1. [Chemical Formula 1] Li 1+x [Fe 1-a-b Mn a M 1 b ]PO4 In the above chemical formula 1, M 1 It contains one or more elements selected from the group consisting of Al, Mg, Ni, Co, Ti, Ga, Cu, V, Mo, Nb, W, Zr, Ce, In, Zn, and Y, and -0.5≤x≤0.5, 0≤a≤0.9, 0≤b≤0.1. When the above conditions are satisfied, it may be desirable in terms of being able to implement excellent economic efficiency and stability. For example, in terms of being able to produce a uniform and stable film-shaped electrode composite film, the electrode active material may include lithium nickel cobalt manganese aluminum oxide. The above negative electrode active material may include at least one selected from the group consisting of lithium metal, a carbon material capable of reversibly intercalating / deintercalating lithium ions, a metal or an alloy of these metals and lithium, a metal composite oxide, a material capable of doping and dedoping lithium, and a transition metal oxide. As the carbon material capable of reversibly intercalating / deintercalating the lithium ion, any carbon-based negative electrode active material generally used in lithium ion secondary batteries can be used without particular limitation, and representative examples thereof include crystalline carbon, amorphous carbon, or a combination of these. Examples of the crystalline carbon include graphite such as natural graphite or artificial graphite in an amorphous, plate-like, flake-like, spherical, or fibrous form, and examples of the amorphous carbon include soft carbon (low-temperature calcined carbon) or hard carbon, mesophase pitch carbide, calcined coke, and the like. As the above metal or an alloy of these metals with lithium, a metal selected from the group consisting of Cu, Ni, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al and Sn or an alloy of these metals with lithium can be used. The above metal composite oxides include PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5, Li. x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1) and Sn x Me 1-x Me' y O z(Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, elements of group 1, 2, and 3 of the periodic table, halogens; 0 <x≤1; 1≤y≤3; 1≤z≤8) 로 이루어진 군에서 선택되는 것이 사용될 수 있다. Materials capable of doping and dedoping the above lithium include Si, SiO. x (0 <x≤2), Si-Y 합금(상기 Y는 알칼리 금속, 알칼리 토금속, 13족 원소, 14족 원소, 전이금속, 희토류 원소 및 이들의 조합으로 이루어진 군에서 선택되는 원소이며, Si은 아님), Sn, SnO2, Sn-Y(상기 Y는 알칼리 금속, 알칼리 토금속, 13족 원소, 14족 원소, 전이금속, 희토류 원소 및 이들의 조합으로 이루어진 군에서 선택되는 원소이며, Sn은 아님) 등을 들 수 있고, 또한 이들 중 적어도 하나와 SiO2를 혼합하여 사용할 수도 있다. 상기 원소 Y로는 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, Ge, P, As, Sb, Bi, S, Se, Te, Po 및 이들의 조합으로 이루어진 군에서 선택될 수 있다. Examples of the above transition metal oxides include lithium-containing titanium composite oxide (LTO), vanadium oxide, and lithium vanadium oxide. Preferably, the electrode active material may include at least one selected from the group consisting of lithium nickel cobalt manganese aluminum oxide and lithium iron phosphate, and more preferably, lithium nickel cobalt manganese aluminum oxide. The conductive agent is a component for further improving the conductivity of the electrode active material, and the conductive agent is not particularly limited as long as it has conductivity without causing a chemical change in the battery, and for example, carbon powder such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, or thermal black; graphite powder such as natural graphite, artificial graphite, or graphite with a highly developed crystal structure; conductive fibers such as carbon fibers or metal fibers; fluorinated carbon powder; conductive powder such as aluminum powder or nickel powder; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; conductive materials such as polyphenylene derivatives, etc. can be used. Specifically, for uniform mixing of the conductive agent and improvement of conductivity, the conductive agent may include at least one selected from the group consisting of activated carbon, graphite, carbon black, and carbon nanotubes (CNTs). The above-mentioned fiberizable binder is not specifically specified as long as it is fibrillizable, and the fibrillation refers to a treatment of dividing a polymer into small pieces. For example, it can be performed using a mechanical shearing force, etc., and the surface of the fibrillated polymer fiber is released so that a large number of fine fibers (fibrils) are generated. The above-mentioned fiberizable binder may preferably include at least one selected from the group consisting of polytetrafluoroethylene (PTFE) and polyolefin, more preferably polytetrafluoroethylene (PTFE), and even more preferably polytetrafluoroethylene (PTFE). Preferably, the polytetrafluoroethylene (PTFE) may be included in an amount of 60 wt% or more based on the total binder weight. At this time, the binder may additionally include at least one of PEO (polyethylene oxide), PVdF (polyvinylidene fluoride), PVdF-HFP (polyvinylidene fluoride-cohexafluoropropylene), and a polyolefin-based binder. Meanwhile, the weight ratio of the electrode active material, the conductive material, and the fiberizable binder may be 80 to 98 wt% : 0.5 to 10 wt% : 0.5 to 10 wt%, and preferably 85 to 98 wt% : 0.5 to 5 wt% : 0.5 to 10 wt%. When the above range is satisfied, the content of the binder may be appropriately included, so that sufficient fiberization can be achieved and the composite powder can be formed and the composite powder can be aggregated to form the electrode composite film, and the physical properties of the electrode composite film can be improved. In the present invention, the electrode composite film may have a porosity of 20% to 50%, specifically 20% to 40%, and more specifically 25% to 35%. When the above range is satisfied, the electrolyte impregnation may be excellent, so that the life characteristics and output characteristics may be improved, and the energy density may be excellent. Meanwhile, the dry electrode may include rolling oil on the surface of the current collector. The rolling oil is not particularly limited as long as it can cool the high-temperature frictional heat generated during rolling and perform the functions of lubricating and removing foreign substances during rolling. Dry electrode manufacturing method According to the present invention, a method for manufacturing a dry electrode includes the steps of (S1) treating the surface of a current collector with atmospheric plasma; and (S2) forming a conductive primer layer on the current collector; wherein the loading speed of the current collector in the atmospheric plasma treatment is 1 m / min to 100 m / min. (S1) Atmospheric pressure plasma treatment step A detailed description of the above-mentioned entire body is omitted as described above, and the atmospheric pressure plasma treatment is described in detail. The method for manufacturing a dry electrode according to the present invention includes a step of treating the surface of a current collector with atmospheric pressure plasma. The range of a ratio between a specific peak intensity and a specific peak intensity measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) for the surface of the current collector described above can be achieved in various ways, but is preferably achieved through atmospheric pressure plasma treatment. In the past, plasma treatment was also performed under a vacuum, but when plasma treatment is performed under a vacuum, there is a disadvantage in that continuous processing is not possible because it is performed in a closed space. In other words, since a vacuum chamber must be used, the process time is long and it is not suitable for mass production or continuous production, so performing an effective continuous process through atmospheric pressure plasma treatment can be more efficient. In the above atmospheric pressure plasma treatment, the loading speed of the entire collector is 1 m / min to 100 m / min, and preferably 2 m / min or more, 3 m / min or more, 4 m / min or more, 5 m / min or more, 6 m / min or more, 7 m / min or more, 8 m / min or more, 9 m / min or more, 10 m / min or more, 11 m / min or more, 12 m / min or more, 13 m / min or more, 14 m / min or more or 15 m / min or more, and may be 95 m / min or less, 90 m / min or less, 85 m / min or less, 80 m / min or less, 75 m / min or less, 70 m / min or less, 65 m / min or less or 60 m / min or less. When the loading speed of the current collector is less than 1 m / min, there is a problem that the current collector is broken due to excessive plasma treatment, or the surface etching is excessive and the rolling oil completely disappears, and there is a problem that the fairness is reduced due to the slow loading speed. When the loading speed of the current collector exceeds 100 m / min, there is a problem that sufficient plasma treatment is not performed due to the fast speed, and the components of the rolling oil do not sufficiently change, resulting in a reduction in the adhesive strength. Therefore, when the above range is satisfied, the breakage of the current collector can be appropriately prevented, and the adhesive strength can be improved by causing a change in the rolling oil through sufficient plasma treatment. The above atmospheric pressure plasma treatment may be performed at an injection flow rate of an inert gas of 650 L / min to 1000 L / min, preferably 675 L / min to 950 L / min, more preferably 700 L / min to 900 L / min, and even more preferably 725 L / min to 900 L / min. The above atmospheric pressure plasma treatment can be performed by injecting an oxygen-containing gas. Preferably, the atmospheric pressure plasma treatment can be performed using an oxygen-containing gas as a plasma activation gas. If the above conditions are satisfied, the plasma treatment can be performed under atmospheric pressure without performing the plasma treatment in a vacuum chamber, so that the processability can be excellent. The above atmospheric pressure plasma treatment may be performed at an injection flow rate of oxygen-containing gas of 0.1 L / min to 10 L / min, preferably 0.5 L / min to 6 L / min, and more preferably 1 L / min to 4 L / min. At this time, the oxygen-containing gas may have an oxygen content of 80 wt% or more, and may preferably be dried air free of foreign substances. The above atmospheric pressure plasma treatment is performed by injecting the oxygen-containing gas flow rate (F O ) Injection flow rate of inert gas (F) N ) for the ratio (F) N / F O ) may be 50 to 10,000, preferably 60 to 5,000, more preferably 90 to 1,000. The above atmospheric pressure plasma treatment may be at a voltage of 10 kV to 20 kV, preferably 11 kV to 19 kV, and more preferably 12 kV to 18 kV. When the above range is satisfied, an appropriate level of plasma can be efficiently generated. The above atmospheric pressure plasma treatment may have a power of 3 kW to 5 kW, preferably 3.2 kW to 4.8 kW, and more preferably 3.4 kW to 4.6 kW. When the above range is satisfied, plasma can be generated with an efficient power amount, so the processability can be excellent. The above atmospheric pressure plasma treatment can be performed with the collector and the plasma nozzle separated by 0.01 mm to 3.00 mm, preferably 0.05 mm to 2.90 mm, more preferably 0.1 mm to 2.5 mm, and even more preferably 0.5 mm to 2.5 mm. The above atmospheric pressure plasma treatment can be performed 1 to 10 times, preferably 1 to 8 times, more preferably 1 to 6 times, even more preferably 1 to 4 times, and even more preferably 1 to 3 times. When the above range is satisfied, sufficient plasma treatment can be applied to the surface of the current collector, thereby realizing excellent adhesive strength. (S2) Conductive primer layer formation step Next, a conductive primer layer is formed on the entire body. The specific composition of the conductive primer layer is omitted as described above, and the conductive primer layer can be formed by a conventional method in the art. By forming the conductive primer layer, the resistance on the surface of the current collector can be lowered and the adhesive strength can be improved, and the conductive primer layer can be formed by coating the entirety or partly with the conductive primer. Meanwhile, the dry electrode manufacturing method according to the present invention may further include a step of forming a conductive primer layer on the current collector, laminating an electrode composite film on one side or both sides of the current collector, and laminating the resultant product to manufacture an electrode. The lamination may be a step of rolling and attaching the electrode composite film on a current collector. The lamination may be performed by a roll press method using a lamination roller, and at this time, the lamination roller may be maintained at a temperature of 20°C to 200°C. The specific composition of the electrode composite film is omitted as described above, and the electrode composite film can be manufactured by including: (a) a step of mixing an electrode active material and a fiberizable binder to obtain a composite composition; (b) a step of kneading the composite composition to prepare a mixed aggregate; (c) a step of pulverizing the mixed aggregate to prepare an electrode powder; and (d) a step of calendering the electrode powder. Below, each step is explained in detail. (a) A step of obtaining a composite composition by mixing an electrode active material and a fiberizable binder is described. Preferably, the step (a) may be a step of obtaining a composite composition by mixing an electrode active material, a conductive material, and a fiberizable binder. The specific compositions of the electrode active material, the conductive material, and the fiberizable binder are omitted as they have been described above. The above mixing is performed so that the electrode active material, the fiberizable binder, and optionally the conductive material can be uniformly distributed, and since they are mixed in a powder form, they can be mixed by various methods without limitation as long as they enable simple mixing thereof. However, since the present invention is manufactured as a dry electrode that does not use a solvent, the mixing can be performed by dry mixing, and the materials can be mixed by putting them into a device such as a mixer or blender. At this time, the mixing can be performed in a mixer at 500 rpm to 20,000 rpm for 1 to 60 minutes, preferably at 600 rpm to 1,800 rpm for 2 to 30 minutes, more preferably at 800 rpm to 1,600 rpm for 3 to 20 minutes, and even more preferably at 1,000 rpm to 1,400 rpm for 5 to 15 minutes. When performed within the above range, the materials can be uniformly mixed, thereby improving battery performance. Next, (b) the step of mixing the composite composition to prepare a mixed aggregate is described. For the composite composition obtained through the mixing, a fiberization process for fiberizing a fiberizable binder can be performed, and preferably, a mixed aggregate can be prepared by mixing. The above mixing can be performed at a speed of 50 rpm to 300 rpm, and preferably at a speed of 70 rpm to 200 rpm. In addition, the above mixing can be performed by loading the composite composition in an amount of 5 kg / h to 40 kg / h, and preferably by loading in an amount of 10 kg / h to 30 kg / h. When the above range is satisfied, appropriate fiberization can proceed, thereby improving the characteristics of the battery. In addition, the mixing can be performed at a temperature of 150° C. to 250° C., preferably 160° C. to 200° C. When mixing is performed at a high temperature such as the above range, the fiberization and lumping of the binder due to mixing can be well achieved, and the problem of breakage of the fiberized binder can be appropriately prevented. Next, (c) the step of crushing the above mixed aggregate to produce powder for electrodes is described. The mixed aggregates manufactured through the above mixing can be directly put into a calendaring process to be filmed into an electrode composite film. However, in this case, the mixed aggregates must be pressed under strong pressure and high temperature to be manufactured into a thin film, and thus, problems arise in that the density of the film becomes too high or a uniform film cannot be obtained. Therefore, the mixed aggregates manufactured as described above are pulverized to manufacture powder for electrodes. The crusher used for the above crushing is not particularly limited, but can preferably be a device such as a blender or grinder. The above grinding can be performed at a speed of 1000 rpm to 6000 rpm for 5 kg / hr to 200 kg / hr, preferably at a speed of 1500 rpm to 4000 rpm for 10 kg / hr to 150 kg / hr. When performed within the above range, sufficient grinding can be achieved so that powder having a size appropriate for filming can be manufactured, and a large amount of fine powder can be prevented from being generated in the mixed aggregate. The average particle size of the above electrode powder may be 10 ㎛ to 3000 ㎛, specifically 50 ㎛ to 1500 ㎛, and more specifically 100 ㎛ to 700 ㎛. When the above range is satisfied, a composite film having a uniform thickness and density can be formed, and excellent composite film properties can be secured. Meanwhile, the electrode powder according to the present invention may additionally include fillers, although not essential, to suppress expansion of the electrode. The filler is not particularly limited as long as it is a fibrous material that does not cause a chemical change in the battery, and examples thereof include at least one selected from olefin polymers such as polyethylene and polypropylene; and fibrous materials such as glass fiber and carbon fiber. Next, (d) the step of calendering the electrode powder is described. An electrode composite film can be manufactured by a calendering method in which the electrode powder is supplied to a calender device and the supplied material is thermally compressed using a roll press(s) included in the calender device. Preferably, the electrode powder according to the present invention can be supplied to a calendar roll and heat-pressed to produce a composite film in the shape of a sheet. At this time, the temperature of the calendar roll can be 50°C to 200°C. The above-mentioned calendar roll includes a roll press section in which two rollers are arranged facing each other, and the roll press sections may be arranged in a plurality of successive numbers. At this time, each roll press section can be appropriately adjusted so that the rotational speed ratio of the two rollers is independently controlled within a range of 1:1 to 1:10. In addition, the manufactured composite film can be put into a roll press section again and heat-pressed 1 to 10 times to adjust it to an appropriate thickness. Lithium secondary battery The lithium secondary battery according to the present invention comprises a dry electrode according to the present invention. More specifically, it comprises a positive electrode, an negative electrode, a separator and an electrolyte, and the positive electrode and / or the negative electrode may be dry electrodes, and preferably, it may be a lithium secondary battery comprising the dry electrode, negative electrode, separator and electrolyte according to the present invention. When only one of the positive electrode or the negative electrode is a dry electrode according to the present invention, the other electrode may be an electrode manufactured through a conventional wet manufacturing method. The above separator separates the negative electrode and the positive electrode and provides a passage for lithium ions to move. If it is a separator commonly used in lithium secondary batteries, it can be used without any special restrictions, and in particular, it is preferable that it has low resistance to ion movement of the electrolyte and excellent electrolyte moisture retention capacity. Preferably, a porous polymer film, for example, a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, and an ethylene / methacrylate copolymer, or a laminated structure of two or more layers thereof, can be used. In addition, a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high-melting-point glass fiber, polyethylene terephthalate fiber, etc. may be used. In addition, a coated separator containing a ceramic component or a polymer material may be used to secure heat resistance or mechanical strength, and may optionally be used in a single-layer or multi-layer structure. In addition, the electrolyte used in the present invention may include, but is not limited to, an organic liquid electrolyte, an inorganic liquid electrolyte, a solid polymer electrolyte, a gel-type polymer electrolyte, a solid inorganic electrolyte, a molten inorganic electrolyte, etc. that can be used in the manufacture of a lithium secondary battery. Preferably, the electrolyte may include an organic solvent and a lithium salt. As the organic solvent, any solvent that can act as a medium through which ions involved in the electrochemical reaction of the battery can move may be used without particular limitation. Preferably, the organic solvent includes ester solvents such as methyl acetate, ethyl acetate, γ-butyrolactone, and ε-caprolactone; ether solvents such as dibutyl ether or tetrahydrofuran; ketone solvents such as cyclohexanone; aromatic hydrocarbon solvents such as benzene and fluorobenzene; Examples of solvents that can be used include carbonate solvents such as dimethylcarbonate (DMC), diethylcarbonate (DEC), methylethylcarbonate (MEC), ethylmethylcarbonate (EMC), ethylene carbonate (EC), and propylene carbonate (PC); alcohol solvents such as ethyl alcohol and isopropyl alcohol; nitriles such as R-CN (wherein R represents a linear, branched, or cyclic hydrocarbon group having 2 to 20 carbon atoms and may include a double-bonded aromatic ring or an ether bond); amides such as dimethylformamide; dioxolanes such as 1,3-dioxolane; and sulfolanes. Among these, a carbonate solvent is preferable, and a mixture of a cyclic carbonate (e.g., ethylene carbonate or propylene carbonate, etc.) having high ionic conductivity and high dielectric constant capable of improving the charge / discharge performance of the battery and a low-viscosity linear carbonate compound (e.g., ethyl methyl carbonate, dimethyl carbonate, or diethyl carbonate, etc.) is more preferable. The above lithium salt can be used without any special limitation as long as it is a compound capable of providing lithium ions used in a lithium secondary battery. Preferably, the anion of the lithium salt is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - and (CF3CF2SO2)2N - At least one selected from the group consisting of LiPF6, LiClO4, LiAsF6, LiBF4, LiSbF6, LiAl04, LiAlCl4, LiCF3SO3, LiC4F9SO3, LiN(C2F5SO3)2, LiN(C2F5SO2)2, LiN(CF3SO2) 2. LiCl, LiI, or LiB(C2O4)2, etc. can be used. It is preferable to use the concentration of the lithium salt within the range of 0.1 M to 4.0 M, preferably 0.5 M to 3.0 M, and more preferably 1.0 M to 2.0 M. When the concentration of the lithium salt is within the above range, the electrolyte can exhibit excellent electrolyte performance because it has appropriate conductivity and viscosity, and lithium ions can move effectively. In addition to the electrolyte components, the electrolyte may further contain one or more additives, such as, for example, haloalkylene carbonate compounds such as difluoroethylene carbonate, pyridine, triethylphosphite, triethanolamine, cyclic ethers, ethylene diamine, n-glyme, hexaphosphoric acid triamide, nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N,N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxy ethanol, or aluminum trichloride, for the purpose of improving the life characteristics of the battery, suppressing battery capacity decrease, and improving the discharge capacity of the battery. In this case, the additives may be contained in an amount of 0.1 to 10.0 wt% with respect to the total weight of the electrolyte. In addition, since the lithium secondary battery according to the present invention stably exhibits excellent discharge capacity, output characteristics, and capacity retention rate, it is useful in the fields of portable devices such as mobile phones, notebook computers, and digital cameras, and electric vehicles such as hybrid electric vehicles (HEVs). Accordingly, according to another embodiment of the present invention, a battery module including the lithium secondary battery as a unit cell and a battery pack including the same are provided. The above battery module or battery pack can be used as a power source for one or more medium- to large-sized devices, including power tools; electric vehicles including electric vehicles (EVs), hybrid electric vehicles, and plug-in hybrid electric vehicles (PHEVs); or power storage systems. Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. Hereinafter, the present invention will be more preferably explained through specific examples. Example 1: Preparation of dry electrodes (Manufacturing of the entire house) A current collector (aluminum alloy thin film) on the surface of which rolling oil exists was treated with plasma at atmospheric pressure to manufacture a current collector treated with atmospheric pressure plasma. Preferably, the atmospheric pressure plasma treatment was performed once at an injection flow rate of 800 LPM for an inert gas (N2), an injection flow rate of 2 LPM for a dried oxygen-containing gas, a voltage of 14 kV, a power of 3.9 kW, a distance between a current collector and a plasma nozzle of 1.5 mm, and moving the current collector at a speed of 40 m / min. (Manufacture of electrode composite film) 96 g of lithium nickel cobalt manganese aluminum oxide as an electrode active material, 1.5 g of carbon black as a conductive material, and polytetrafluoroethylene (PTFE) as a binder were placed in a blender and mixed at 10,000 rpm for 1 minute to prepare a composite composition. Thereafter, the composite composition was placed in a kneader and kneaded at a rotation speed of 50 rpm at a temperature of 150°C and a pressure of 1.1 atm for 5 minutes to produce a mixed aggregate. The mixed aggregate was placed in a blender and ground at 10,000 rpm for 40 seconds to obtain a powder for an electrode. The above electrode powder was sheeted onto a rolling roll in a roll-to-roll process and then rolled onto a rolling roll (roll diameter: 200 mm, roll temperature: 100°C, rotation speed: 20 rpm) to manufacture an electrode composite film. (Manufacture of dry electrodes) Thereafter, a conductive primer layer was formed on the current collector treated with the atmospheric pressure plasma, and the current collector on which the conductive primer layer was formed and the electrode composite film were laminated through a roll press to manufacture a dry electrode. Example 2: Preparation of dry electrodes A dry electrode was manufactured in the same manner as in Example 1, except that the atmospheric pressure plasma treatment was performed twice at an injection flow rate of 800 LPM for an inert gas (N2), an injection flow rate of 2 LPM for a dried oxygen-containing gas, a voltage of 14 kV, an electric power of 3.9 kW, a distance between a current collector and a plasma nozzle of 1.5 mm, and moving the current collector at a speed of 40 m / min. Example 3: Preparation of dry electrodes A dry electrode was manufactured in the same manner as in Example 1, except that the atmospheric pressure plasma treatment was performed once at an injection flow rate of 800 LPM for an inert gas (N2), an injection flow rate of 2 LPM for a dried oxygen-containing gas, a voltage of 14 kV, a power of 3.9 kW, a distance between a current collector and a plasma nozzle of 1.5 mm, and moving the current collector at a speed of 20 m / min. Example 4: Preparation of dry electrodes A dry electrode was manufactured in the same manner as in Example 1, except that the atmospheric pressure plasma treatment was performed twice at an injection flow rate of 800 LPM for an inert gas (N2), an injection flow rate of 2 LPM for a dried oxygen-containing gas, a voltage of 14 kV, an electric power of 3.9 kW, a distance between a current collector and a plasma nozzle of 1.5 mm, and moving the current collector at a speed of 20 m / min. Comparative Example 1: Dry Electrode Manufacturing A dry electrode was manufactured in the same manner as in Example 1, except that atmospheric pressure plasma treatment was not performed. Comparative Example 2: Dry Electrode Manufacturing A dry electrode was manufactured in the same manner as in Example 1, except that the atmospheric pressure plasma treatment was performed while moving the collector at a speed of 200 m / min. The manufacturing method of the dry electrodes manufactured according to the above Examples 1 to 4 and Comparative Examples 1 to 2 is summarized and shown in [Table 1] below. Atmospheric pressure plasma treatment conditionsInert gas flow rate(L / min)Dried oxygen-containing gas flow rate(L / min)Voltage(kV)Power(kW)Distance between collector and plasma nozzle(mm)Collector moving speed(m / min)Number of performancesExample 18002143.91.5401Example 28002143.91.5402Example 38002143.91.5201Example 48002143.91.5202Comparative example 1------0Comparative example 28002143.91.52001 Experimental Example 1: ToF-SIMS and SEM-EDX Analysis 1) ToF-SIMS analysis For each of the collectors manufactured in Examples 1 to 4 and Comparative Examples 1 to 2, ToF-SIMS analysis was performed to analyze the organic components remaining on the surface of the collector. In detail, the collectors manufactured in Examples 1 to 4 and Comparative Examples 1 to 2 were cut into 50 mm x 50 mm pieces, and then analysis was performed using TOF-SIMS 5 from Ion-TOF Corporation under the following conditions. 1) Positive mode 2) Measurement mass range: 1u to 873u 3) Primary ion: Bi3 4) Primary ion dose: 3.81ⅹ10 8 ions / cm 2 5) Voltage: 30KeV 6) Detection time: 100 seconds 7) FOV (field of view): 100㎛ⅹ100㎛ Measured C2H3O + Peak intensity, C3H7 + Peak intensities and the sum of all measured ions are shown in Table 2 below. 2) SEM-EDX measurement For the dry electrodes manufactured in Examples 1 to 4 and Comparative Examples 1 to 2, the ratio of the carbon content at the collector interface to the carbon content inside the electrode composite film was measured using a scanning electron microscope-energy dispersive X-ray spectroscopy. 1) Equipment: JSM-IT800 (JEOL) 2) Acceleration voltage: 5kV 3) Incident current: 2.3nA, High current mode 4) Working Distance: 10mm 5) Total count during mapping: 35000cps The measured results are shown in Table 2 below. ToF-SIMSSEM-EDXC2H3O + Peak intensity (I A , counts)C3H7 + Peak intensity (I B , counts)Measured total ion counts (I T , counts)I B / I A I B / I T (ⅹ10 -5 )I A / I T (ⅹ10 -5 ) Non-example of the carbon content of the current collector interface relative to the carbon content inside the electrode composite film 113016533495421504810.2573793091.52Example 211521133000434472510.2864762651.52Example 310500332500417485040.3095782521.52Example 47409532500403071130.4386811841.52Comparative example 15201786001366550971.6532351421.52Comparative example 25813578068368562191.34292121581.52 Experimental Example 3: Evaluation of the presence or absence of peeling of the conductive primer layer and evaluation of the electrode appearance (Evaluation of the presence or absence of conductive primer layer peeling) For each of the current collectors formed with the conductive primer layer manufactured in Examples 1 to 4 and Comparative Examples 1 to 2, the presence or absence of peeling of the conductive primer layer was evaluated using 3M Scotch tape. Specifically, when 3M Scotch tape was attached to the surface on which the conductive primer layer was formed and separated, if the conductive primer layer was peeled off, it was evaluated as X, and if the conductive primer layer was not peeled off, it was evaluated as O. The evaluation results are shown in Table 3 below. (Evaluation of electrode appearance) The dry electrodes manufactured in Examples 1 to 4 and Comparative Examples 1 to 2 were immersed in an electrolyte, sealed, and stored in an oven at 70°C for 4 weeks. After that, the stored dry electrodes were taken out, rinsed, and then evaluated for appearance. Specifically, for the appearance evaluation, if there was lifting of the electrode composite film in a dry electrode rinsed with dimethyl carbonate (DMC), it was evaluated as X, and if there was no lifting, it was evaluated as O. The evaluation results are shown in Table 3 below. Conductive primer layer peeling evaluation Electrode appearance evaluation Example 1OO Example 2OO Example 3OO Example 4OO Comparative Example 1XX Comparative Example 2XX Referring to Table 3 above, in the case of Examples 1 to 4, unlike Comparative Examples 1 to 2, it can be confirmed that the conductive primer layer is not easily separated from the current collector and there is no lifting in the appearance of the electrode.

Claims

1. A current collector; and an electrode composite film disposed on the current collector; The above electrode composite film comprises an electrode active material and a fiberizable binder, For the surface of the above collector, C2H3O measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) + Peak intensity (I A ) for C3H7 + Peak intensity (I B ) rain (I B / I A ) is less than or equal to 1.3, A dry electrode having a ratio of the carbon content at the current collector interface to the carbon content inside the electrode composite film as measured by a scanning electron microscope-energy dispersive X-ray spectroscopy of 1.08 or more.

2. In paragraph 1, For the surface of the above-mentioned collector, the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) T ) for C3H7 + Peak intensity (I B ) rain (I B / I T ) is 230x10 -5 Dry electrodes below.

3. In paragraph 1, For the surface of the above-mentioned collector, the total ion counts (I) measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) T ) for C2H3O + Peak intensity (I A ) rain (I A / I T ) is 1000x10 -5 Dry electrodes below.

4. In paragraph 1, The above-mentioned collector is a dry electrode containing aluminum.

5. In paragraph 1, The tensile strength of the entire above-mentioned collector is 5 kgf / mm 2 Ideal dry electrode.

6. In paragraph 1, A dry electrode having a water contact angle of 10° to 100° on the surface of the above-mentioned collector.

7. In paragraph 1, A dry electrode comprising rolling oil on the surface of the above-mentioned collector.

8. Step of treating the surface of the entire body with atmospheric pressure plasma; and A step of forming a conductive primer layer on the entire body of the above-mentioned body; A dry electrode manufacturing method wherein the loading speed of the current collector in the above atmospheric pressure plasma treatment is 1 m / min to 100 m / min.

9. In paragraph 8, The above atmospheric pressure plasma treatment is a dry electrode manufacturing method in which the injection flow rate of an inert gas is 500 L / min to 1000 L / min and the injection flow rate of an oxygen-containing gas is 0.1 L / min to 10 L / min.

10. In paragraph 8, The above atmospheric pressure plasma treatment is a dry electrode manufacturing method in which the ratio of the injection flow rate of an inert gas to the injection flow rate of an oxygen-containing gas is 50 to 10,000.

11. In paragraph 8, A dry electrode manufacturing method wherein the above atmospheric pressure plasma treatment is performed at a voltage of 10 kV to 20 kV.

12. In paragraph 8, A dry electrode manufacturing method wherein the above atmospheric pressure plasma treatment has a power of 3 kW to 5 kW.

13. In paragraph 8, A dry electrode manufacturing method in which the above atmospheric pressure plasma treatment is performed with the collector and plasma nozzle separated by 0.01 mm to 3.00 mm.

14. A lithium secondary battery comprising the dry electrode of paragraph 1.

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