KR101540618B1 - Electrode for Secondary Battery and Method of Preparing the Same - Google Patents

Abstract

 (A) an electrode mixture coating layer composed of an electrode mixture including an electrode active material, a binder and a conductive material; And (b) a carbon slurry coating layer composed of a carbon slurry and coated on at least a part of an interface between the electrode mixture coating layer and the current collector; The present invention provides an electrode for a secondary battery and a method of manufacturing the same, which can significantly improve the adhesive force and the output characteristic between the electrode material mixture and the current collector.

Description

Technical Field [0001] The present invention relates to an electrode for a secondary battery,

The present invention relates to an electrode for a secondary battery and a manufacturing method thereof,

(a) an electrode mixture coating layer composed of an electrode mixture including an electrode active material, a binder, and a conductive material; And

(b) a carbon slurry coating layer composed of a carbon slurry and coated on at least a part of an interface between the electrode mixture coating layer and the current collector;

And an electrode for a secondary battery, and a method of manufacturing the same.

As technology development and demand for mobile devices have increased, there has been a rapid increase in the demand for secondary batteries as energy sources. Many researches have been made on lithium secondary batteries having high energy density and discharge voltage among such secondary batteries, and they are widely used and widely used have.

Generally, a lithium secondary battery comprises a separator disposed between an anode, a cathode, and both electrodes, and an electrolytic solution, and an electrolyte in which an appropriate amount of a lithium salt is dissolved in an organic solvent is used.

The electrode of such a lithium secondary battery is generally prepared by coating a current collector with a slurry for an electrode material mixture. The slurry for the electrode material mixture includes an electrode active material for intercalating and deintercalating lithium ions, a conductive material for imparting electrical conductivity , And a binder for bonding the electrode foil to the electrode foil in a solvent such as N-methyl pyrrolidone (NMP). However, in the production of such electrodes, the adhesion between the electrode material mixture and the current collector may be lowered during the pressing process or the subsequent manufacturing process, and dust may be generated. As a result of the volume change of the electrode caused by the progress of charging and discharging of the battery, The active material or the electrode active material may be desorbed between the electrode active material and the current collector so that the active material may not function properly.

Such deterioration of adhesive strength and detachment of the active material due to the deterioration of the active material increases the internal resistance of the battery, thereby deteriorating output characteristics and decreasing the battery capacity.

Accordingly, in order to solve the above problems, various methods have been proposed, such as forming fine irregularities by etching the surface of the current collector, or applying a specific substance to the surface of the current collector to increase the bonding force with the current collector.

However, in spite of these attempts, the dust phenomenon due to the decrease of the adhesion force between the electrode mixture and the current collector is not completely solved in the manufacturing process of the electrode, and due to the substance applied on the surface of the current collector, There is a problem in that the electrical conductivity of the electrode is reduced.

Therefore, there is a high need for a technique capable of improving the bonding force without damaging the electrical conductivity between the current collector and the electrode mixture.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments and have succeeded in achieving a desired effect when using an electrode for a secondary battery in which a carbon slurry coating layer and an electrode mixture coating layer are continuously included as described later And the present invention has been accomplished.

Therefore, in the electrode for a secondary battery according to the present invention,

(a) an electrode mixture coating layer composed of an electrode mixture including an electrode active material, a binder, and a conductive material; And

(b) a carbon slurry coating layer composed of a carbon slurry and coated on at least a part of an interface between the electrode mixture coating layer and the current collector;

And a control unit.

That is, since the electrode for a secondary battery according to the present invention is coated with a carbon slurry, the electrical conductivity between the current collector and the electrode mixture can be improved, and the carbon slurry layer has an effect of widening the surface area, It has the advantage of increasing the adhesive strength of the compound.

The carbon slurry may contain at least one carbonaceous material selected from the group consisting of graphite, carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, And may include a polymer material as a binder.

As the binder, the polymer material may be polyvinylidene fluoride (PVdF), polyvinyl alcohol, carboxymethylcellulose (CMC), polyvinylidene fluoride (PVDF), or the like as a component that assists in bonding of the carbon- , Starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene- Rubber, and fluororubber, but is not limited thereto. Concretely, it may be polyvinylidene fluoride (PvdF).

The carbon-based material may be contained in an amount of 20 to 80% by weight based on the total weight of the carbon slurry. If the amount of the carbonaceous material is too large, the amount of the binder may be relatively small and the adhesion may be deteriorated. On the other hand, if the amount is too small, the desired electrical conductivity may not be obtained. Specifically, the carbon-based material may be 30 to 70% by weight based on the total weight of the carbon slurry.

The carbon slurry coating layer may be 0.5 to 50 탆 thick. If the thickness of the carbon slurry coating layer is too small, it is difficult to exhibit a desired electric conductivity improving effect. On the other hand, if the carbon slurry coating layer is too thick, the coating amount of the electrode mixture layer decreases. Therefore, the thickness of the carbon slurry coating layer may be specifically from 10 to 40 mu m.

The carbon slurry coating layer can be coated on all or a part of the surface of the current collector, and can be appropriately controlled within a range capable of improving the bonding force and electric conductivity with the electrode mixture. The carbon slurry coating layer may be formed at a ratio of 50 to 100% based on the surface area of the current collector to which the electrode mixture contacts. Specifically, the carbon slurry coating layer may be 80 to 100%.

The surface roughness of the carbon slurry coating layer can be appropriately adjusted according to the solid content ratio of the carbon slurry, and may be, for example, from 0.01 to 30 탆, and specifically from 0.1 to 10 탆. The carbon slurry coating layer having such a surface roughness can increase the interface area with the electrode mixture coating layer, and consequently the adhesion can be improved.

The interface between the carbon slurry coating layer and the electrode mixture coating layer may have a concavo-convex interface structure.

The thickness of the electrode mixture coating layer may be 5 to 400 탆, and may be 20 to 200 탆. When the thickness of the coating layer is too small, it is difficult to expect the effect of coating. On the other hand, if it is too large, fusion of the current collector is inhibited.

The density of the electrode for the secondary battery may be 1.5 to 5 g / cc. With such an electrode density, it is possible to maintain a large contact area with the current collector, so that it is possible to form an excellent conductive network, and thus the electric conductivity is excellent.

The electrode active material may be a positive electrode active material, a negative electrode active material, or a positive electrode active material and a negative electrode active material.

Further, in the method of manufacturing an electrode for a secondary battery according to the present invention,

(a) coating a carbon slurry on a part or whole surface of the current collector and drying to form a carbon slurry coating layer;

(b) coating an electrode mixture including an electrode active material, a binder, and a conductive material on the collector on which the carbon slurry coating layer is formed, and drying the electrode mixture to form an electrode mixture coating layer;

(c) roll-pressing the continuously coated carbon slurry coating layer and the electrode mixture coating layer;

(d) applying the steps (a), (b) and (c) one or more times;

As shown in FIG.

In the step (a), the surface roughness of the carbon slurry coating layer can be controlled by adjusting the solid content ratio of the carbon slurry as described above.

In the step (b), by continuously coating the electrode slurry coating layer on the carbon slurry coating layer, the processability can be improved by reducing the manufacturing process ratio, and the interface area between the carbon slurry coating layer and the electrode slurry coating layer can be increased.

The drying of step (a) and step (b) may be carried out at a temperature at which the binder in the carbon slurry and electrode slurry slurry is not denatured, for example, the drying may be carried out at 80 to 200 DEG C for 1 to 20 minutes Can be performed. More specifically, it may be carried out at 100 to 150 DEG C for 1 to 10 minutes.

In the step (c), the electrode mixture penetrates into the surface of the carbon slurry coating layer at the interface between the carbon slurry coating layer and the electrode mixture coating layer formed by the continuous pressing through roll pressing to improve the contact with the carbon slurry coating layer have. In this case, the degree of penetration of the electrode mixture, specifically, the cathode active material, can be controlled through the adjustment of the solid content ratio of the carbon slurry in the step (a).

According to the manufacturing method of the present invention, the steps (a), (b), and (c) are repeated one or more times to form a secondary slurry containing the carbon slurry coating layer and the electrode slurry coating layer It is possible to provide a battery electrode.

The present invention also provides a secondary battery comprising the secondary battery electrode as a positive electrode or a negative electrode, or a positive electrode and a negative electrode, and the secondary battery may specifically be a lithium secondary battery.

Hereinafter, the configuration of such a lithium secondary battery will be described.

The lithium secondary battery includes a positive electrode prepared by applying a mixture of a positive electrode active material, a conductive material and a binder on a positive electrode collector, followed by drying and pressing, and a negative electrode prepared using the same method. In this case, A filler is further added to the mixture.

The cathode current collector generally has a thickness of 3 to 500 mu m. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery. Examples of the positive electrode current collector include stainless steel, aluminum, nickel, titanium, sintered carbon, aluminum or stainless steel A surface treated with carbon, nickel, titanium, silver or the like may be used. The current collector may have fine irregularities on the surface thereof to increase the adhesive force of the cathode active material, and various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric are possible.

The cathode active material may be, for example, a layered compound such as lithium cobalt oxide (LiCoO ₂ ) or lithium nickel oxide (LiNiO ₂ ) or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li _{1 + x} Mn _{2 -x} O ₄ (where x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , LiMnO ₂ and the like; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ and Cu ₂ V ₂ O ₇ ; A Ni-site type lithium nickel oxide expressed by the formula LiNi _1-x M _x O ₂ (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0.3); Formula _{LiMn 2-x M x O 2} ( where, M = Co, Ni, Fe , Cr, and Zn, or Ta, x = 0.01 ~ 0.1 Im) or Li ₂ Mn ₃ MO ₈ (where, M = Fe, Co, Ni, Cu, or Zn); LiMn ₂ O _{4 in} which a part of Li in the formula is substituted with an alkaline earth metal ion; Lithium nickel manganese cobalt composite oxides such as LiNi _1/3 Mn _1/3 Co _1/3 O ₂ and LiNi _0.5 Mn _0.3 Ni _0.2 ; Fe ₂ (MoO ₄ ) ₃ , and LiNi _x Mn _2-x O ₄ (0.01 ≦ x ≦ 0.6).

The conductive material is usually added in an amount of 1 to 50% by weight based on the total weight of the mixture including the cathode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The binder is a component that assists in bonding of the active material and the conductive material and bonding to the current collector, and is usually added in an amount of 1 to 50 wt% based on the total weight of the mixture containing the cathode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , Polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, fluorine rubber, and various copolymers.

The filler is optionally used as a component for suppressing expansion of the anode, and is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery. Examples of the filler include olefin-based polymerizers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The negative electrode current collector is generally made to have a thickness of 3 to 500 mu m. Such an anode current collector is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, and examples of the anode current collector include copper, stainless steel, aluminum, nickel, titanium, sintered carbon, a surface of copper or stainless steel A surface treated with carbon, nickel, titanium, silver or the like, an aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

The negative electrode active material may be, for example, graphite having a completely layered crystal structure such as natural graphite, soft carbon having a low crystalline layered crystal structure (a structure in which hexagonal honeycomb planes of carbon are arranged in layers) Carbon and graphite materials such as hard carbon, artificial graphite, expanded graphite, carbon fiber, hard graphitizable carbon, carbon black, carbon nanotube, fullerene, activated carbon and the like in which these structures are mixed with amorphous portions; _{Li x Fe 2 O 3 (0≤x≤1} ), Li x WO 2 (0≤x≤1), Sn x Me 1 - x Me 'y O z (Me: Mn, Fe, Pb, Ge; Me' : Metal complex oxides such as Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, Halogen, 0 < x &lt; Lithium metal; Lithium alloy; Silicon-based alloys; Tin alloy; _{SnO, SnO 2, PbO, PbO} 2, Pb 2 O 3, Pb 3 O 4, Sb 2 O 3, Sb 2 O 4, Sb 2 O 5, GeO, GeO 2, Bi 2 O 3, Bi 2 O 4, and Bi ₂ O ₅ ; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like; Complexes of the above compounds may be used.

Such a lithium secondary battery may have a structure in which a lithium salt-containing electrolyte is impregnated in an electrode assembly having a separator interposed between a cathode and an anode.

The separation membrane is interposed between the anode and the cathode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the separator is generally 0.01 to 10 mu m and the thickness is generally 5 to 300 mu m. Such separation membranes include, for example, olefinic polymers such as polypropylene, which are chemically resistant and hydrophobic; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The electrolyte solution containing the lithium salt is composed of an electrolyte solution and a lithium salt. The electrolyte solution may be a non-aqueous organic solvent, an organic solid electrolyte, or an inorganic solid electrolyte, but is not limited thereto.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , Acetonitrile, nitromethane, methyl formate, methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate Nonionic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyrophosphate, ethyl propionate and the like can be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, A polymer containing an ionic dissociation group and the like may be used.

Examples of the inorganic solid electrolyte include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides and sulfates of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ can be used.

The lithium salt is a material that is readily soluble in the non-aqueous electrolyte, for example, LiCl, LiBr, LiI, LiClO 4, LiBF 4, LiB 10 Cl 10, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF _{6, LiSbF 6, LiAlCl 4,} CH 3 SO 3 Li, (CF 3 SO 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide.

For the purpose of improving the charge / discharge characteristics and the flame retardancy, the electrolytic solution is preferably mixed with an organic solvent such as pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, Benzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, . In some cases, halogen-containing solvents such as carbon tetrachloride and ethylene trifluoride may be further added to impart nonflammability. In order to improve the high-temperature storage characteristics, carbon dioxide gas may be further added. FEC (Fluoro-Ethylene Carbonate, PRS (Propene sultone), and the like.

In one _{example, LiPF 6, LiClO 4, LiBF} 4, LiN (SO 2 CF 3) A lithium salt of _2, and so on, highly dielectric solvent of DEC, DMC or EMC linear in FIG solvent cyclic carbonate and a low viscosity of the EC or PC Carbonate in a mixed solvent to prepare a non-aqueous electrolyte containing a lithium salt.

Since the lithium secondary battery including the electrode according to the present invention has a reduced internal resistance, the battery pack including the same can be used as a power source for vehicles requiring high temperature stability, long cycle characteristics, high rate characteristics, and long life characteristics.

Examples of the vehicle may be an electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV) But is not limited thereto.

As described above, since the electrode for a secondary battery according to the present invention is manufactured through a roll freshening process in which a carbon slurry coating layer and an electrode material mixture coating layer are successively formed on a current collector, the adhesive force between the electrode material mixture and the current collector is improved, Can be reduced, and the secondary battery including the secondary battery can exhibit excellent output characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the HPPC resistance of a secondary battery including a positive electrode prepared according to Example 1 and Comparative Examples 1 and 2, respectively;
FIG. 2 is a graph showing a charge-discharge cycle of a secondary battery including a positive electrode prepared according to Example 1 and Comparative Examples 1 and 2, respectively.

Hereinafter, the present invention will be described in more detail with reference to some embodiments thereof, but the scope of the present invention is not limited thereto.

&Lt; Example 1 >

1-1. Preparation and coating of carbon slurry

Super-P 65 (carbon) as a carbon-based material and polyvinylidene fluoride (PVdF: KF1100) as a binder were mixed at a weight ratio of 60:40. N-methylpyrrolidone (NMP) Slurry. The carbon slurry prepared above was coated on an aluminum foil with a thickness of 20 mu m and dried in an oven at 120 DEG C for 5 minutes.

1-2. Preparation and coating of positive electrode mixture

A: (KF1100 PVdF) 90: LiNi 1/3 Mn 1/3 Co 1/3 O 2, as the conductive material as a Super-P 65 and a binder of polyvinylidene fluoride as a positive electrode active material were mixed at a weight ratio of 5: 5 N-methylpyrrolidone (NMP) was added dropwise to the mixture to prepare an electrode mixture. The electrode mix prepared above was applied to an aluminum foil coated with a carbon slurry and dried at 120 DEG C for 10 minutes.

1-3. Performing roll pressing

Roll-pressing was performed on the anode produced through steps 1-1 and 1-2.

&Lt; Comparative Example 1 &

A cathode for a secondary battery was prepared in the same manner as in Example 1 except that the aluminum foil was coated with a carbon slurry and an electrode mixture, and then roll pressing was not performed.

&Lt; Comparative Example 2 &

The same procedure as in Example 1 was carried out except that the aluminum foil was coated with a carbon slurry, followed by roll pressing, and the electrode mixture was coated on the carbon slurry coating layer on which the roll pressing was performed, To prepare a positive electrode for a secondary battery

<Experimental Example 1>

In order to compare the bonding strength of the positive electrode mixture to the current collector in the positive electrode according to Example 1 and Comparative Examples 1 and 2, the prepared positive electrode surfaces were cut to a predetermined size and fixed on a slide glass, and then the aluminum foil was peeled And the peel strength at 180 캜 was measured. The results are shown in Table 1 below.

<Table 1>

As shown in Table 1, the positive electrode of Example 1 according to the present invention exhibits a higher adhesion force than the positive electrodes of Comparative Examples 1 and 2. That is, it was found that the bonding force of the positive electrode mixture to the current collector was improved by the roll pressing performed after the continuous formation of the carbon slurry layer and the electrode mixture layer in the current collector.

<Experimental Example 2>

Each of the pouch-type single layer cells having a capacity of 20 mAh with 1 C cell capacity including the positive electrode prepared according to Example 1 and Comparative Examples 1 and 2 was prepared.

An anode slurry prepared by mixing natural graphite: CMC: SBR binder: carbon conductive material (super-C65) in a ratio of 95: 1: 2: 2 was coated on a copper foil with a thickness of 60 탆 and dried. Unlike the positive electrode, no carbon slurry was applied. Polyethylene was used as a separator.

The cell resistance was measured at room temperature (25 degrees Celsius) using the HPPC measurement method. Then, the same cell was measured for charging / discharging cycle characteristics under the condition of 45 degrees charging 1 C / discharging 2 C, And 2, respectively.

<Table 2>

According to Table 2 and FIGS. 1 and 2, the anode of Example 1 is reduced in the interfacial resistance between the cathode mixture and the current collector as compared with the cathode of Comparative Examples 1 and 2, so that the cell resistance is reduced. The output characteristics can be improved. Such a resistance difference becomes more noticeable in a middle- or large-sized secondary battery using an increased number of cycles or a large amount of active material or the like in one battery cell.

Further, due to the high adhesive force of the positive electrode of Example 1, the secondary battery including the positive electrode of the present invention has a problem in that, due to mechanical stress caused by gas generation due to side reactions during charging and discharging, by- It is possible to exhibit improved life characteristics even when contact deterioration occurs between the whole electrode assembly and the electrode assembly.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (14)

An electrode material mixture coating layer composed of an electrode active material, a binder, a conductive material, and an electrode mixture including N-methyl pyrrolidone (NMP), and a carbon slurry, and is coated on at least a part of the interface between the electrode material mixture coating layer and the current collector Wherein the carbon slurry includes a carbonaceous material and a binder, the carbonaceous material is contained in an amount of 20 to 80 wt% based on the total weight of the carbon slurry, To 50% by weight based on the surface area of the electrode,
(a) coating a carbon slurry on a part or whole surface of the current collector and drying to form a carbon slurry coating layer;
(b) coating an electrode mixture containing an electrode active material, a binder, a conductive material, and N-methyl pyrrolidone (NMP) on the collector on which the carbon slurry coating layer is formed, and drying the electrode mixture coating layer;
(c) roll-pressing the continuously coated carbon slurry coating layer and the electrode mixture coating layer; And
(d) applying the steps (a), (b) and (c) one or more times;
&Lt; / RTI &gt; The carbonaceous material according to claim 1, wherein the carbonaceous material is at least one selected from the group consisting of graphite, carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, Wherein the binder is a polymeric material. The method of claim 2, wherein the polymeric material is selected from the group consisting of polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene Is at least one selected from the group consisting of ethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butylen rubber and fluororubber. delete The method according to claim 1, wherein the carbon slurry coating layer has a thickness of 0.5 to 50 탆. delete The method of claim 1, wherein the surface roughness of the carbon slurry coating layer is in the range of 0.01 to 30 탆. The manufacturing method according to claim 1, wherein the interface between the carbon slurry coating layer and the electrode mixture coating layer has a concavo-convex interface structure. The method according to claim 1, wherein the electrode material mixture coating layer has a thickness of 5 to 400 탆. The method according to claim 1, wherein the density of the electrode is 1.5 to 5 g / cc. delete 2. The process according to claim 1, wherein the drying of step (a) and step (b) is performed at 80 to 200 DEG C for 1 to 20 minutes. delete delete

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