Method of manufacturing an electrode including formation of a dam line coating layer

Abstract

The present invention relates to a method for manufacturing an electrode, comprising the steps of: forming a dam line coating layer having a predetermined width on a current collector and surrounding an area to be coated with an electrode slurry; coating an electrode slurry within the area surrounded by the dam line coating layer to form an electrode composite layer; and drying the current collector on which the dam line coating layer and the electrode composite layer are formed.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing an electrode, and more specifically, to a method for manufacturing an electrode comprising the formation of a dam line coating layer. Background Technology

[0003] Recently, rechargeable secondary batteries are being widely used as an energy source for wireless mobile devices. Furthermore, secondary batteries are attracting attention as an energy source for electric vehicles and hybrid electric vehicles, which are being proposed as solutions to address air pollution caused by conventional gasoline and diesel vehicles that use fossil fuels. Consequently, the types of applications utilizing secondary batteries are becoming highly diversified due to their advantages, and it is expected that secondary batteries will be applied to a wider range of fields and products in the future than they are today.

[0004] These secondary batteries are classified into lithium-ion batteries, lithium-ion polymer batteries, and lithium-polymer batteries depending on the composition of the electrodes and electrolytes; among these, the use of lithium-ion polymer batteries is increasing due to their low risk of electrolyte leakage and ease of manufacturing. Generally, secondary batteries are classified according to the shape of the battery case into cylindrical and prismatic batteries, in which the electrode assembly is housed in a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode assembly is housed in a pouch-type case made of an aluminum laminate sheet. The electrode assembly housed in the battery case is a power generation element capable of charging and discharging, consisting of a positive electrode, a negative electrode, and a separator structure interposed between the positive and negative electrodes. It is further classified into a jelly-roll type, which is wound with a separator interposed between long sheet-type positive and negative electrodes coated with active material, and a stack type, in which multiple positive and negative electrodes of a predetermined size are sequentially stacked with a separator interposed between them.

[0005] These electrodes can be manufactured by forming an electrode composite layer by coating an electrode slurry containing an electrode active material onto a current collector and then drying it. This coating of the electrode slurry can generally be performed using a slot die-shaped coating device. In this case, for the electrode to exhibit maximum performance, a large amount of the electrode active material must be contained within a narrow space, and to increase charge / discharge efficiency with the same amount of active material, the electrode composite layer must be formed with a uniform thickness and width. In particular, as coating dies are enlarged and coating processes are accelerated to realize high-quality and high-efficiency products and increase production efficiency, the issue of ensuring that the thickness and width of the electrode composite layer are uniform throughout has emerged as an increasingly important technical problem.

[0006] Figure 1 is a schematic diagram showing the coating shape of a typical electrode. Figure 1 (a) shows the top surface of the electrode, and Figure 1 (b) shows the side surface of the electrode.

[0007] Referring to FIG. 1, a general electrode (1) has a structure in which an electrode composite layer (20) is formed on a current collector (10) as previously described. However, during the process of coating the electrode slurry onto the current collector, a variation may occur in the amount of electrode slurry discharged along the width direction, and as the coated electrode slurry spreads out due to gravity, the width and length of the electrode composite layer may become uneven. Furthermore, there was a problem that a variation in thickness between the edges and the center of the electrode composite layer may occur due to the above-mentioned phenomenon. Prior art literature

[0009] Korean Registered Patent No. 10-1948623 The problem to be solved

[0010] The present invention was devised to solve the above-mentioned problems and aims to provide an electrode manufacturing method capable of minimizing variations in width, length, and thickness of the electrode composite layer. means of solving the problem

[0012] A method for manufacturing an electrode according to the present invention comprises: a step of forming a dam line coating layer having a predetermined width on a current collector and surrounding a region to be coated with an electrode slurry; a step of forming an electrode composite layer by coating an electrode slurry within the region surrounded by the dam line coating layer; and a step of drying the current collector on which the dam line coating layer and the electrode composite layer are formed.

[0013] In a specific example, the dam line coating layer can be formed by coating a dam line forming slurry around the perimeter of the area where the electrode slurry is coated.

[0014] At this time, the angle formed by the surface of the dam line coating layer with the current collector may be 60 to 90°.

[0015] In one example, the polymer, solvent, and binder included in the slurry for forming the dam line may be hydrophobic.

[0016] In a specific example, the polymer included in the slurry for forming the dam line may be insulating.

[0017] In a more specific example, the polymer included in the slurry for forming the dam line may be selected from the group comprising polybutadiene, polyurethane, polyimide, polyester, polycarbonate, polyphenylenesulfide (PPS), polyolefin, polydimethylsiloxane (PDMS), styrene-butadiene copolymer, (meth)acrylate, polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), and mixtures thereof.

[0018] In another example, the dam line coating layer can be formed by placing a guide member that surrounds the area where the dam line coating layer is formed on the current collector, and filling the area surrounded by the guide member with a slurry for forming a dam line.

[0019] In a specific example, the thickness of the dam line coating layer may be the same as the thickness of the electrode composite layer.

[0020] In one example, the dam line coating layer can be dried together with the electrode composite layer.

[0021] In another example, the dam line coating layer can be dried before the formation of the electrode composite layer.

[0022] At this time, the dam line coating layer may be partially dried before the formation of the electrode composite layer.

[0023] In addition, the present invention provides an electrode manufactured by the method described above, wherein the electrode has a structure comprising: a current collector; an electrode composite layer formed on the current collector; and a dam line coating layer surrounding the electrode composite layer. Effects of the invention

[0025] The present invention can minimize variations in width, length, and thickness of the electrode composite layer by pre-forming a dam line coating layer surrounding the area to be coated of the electrode slurry before coating the electrode slurry. Brief explanation of the drawing

[0027] Figure 1 is a schematic diagram showing the coating shape of a typical electrode. FIG. 2 is a flowchart showing the sequence of the method for manufacturing an electrode according to the present invention. FIGS. 3 and FIGS. 4 are schematic diagrams showing the structure of an electrode according to the present invention. FIG. 5 is a schematic diagram showing the structure of an electrode according to one embodiment of the present invention. FIG. 6 is a schematic diagram showing the manufacturing process of an electrode according to another embodiment of the present invention. FIGS. 7 and FIGS. 8 are flowcharts showing the sequence of a method for manufacturing an electrode according to another embodiment of the present invention. Specific details for implementing the invention

[0028] The present invention will be described in detail below. Prior to this, terms or words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor may appropriately define the concepts of terms to best describe their invention, they must be interpreted in a meaning and concept consistent with the technical spirit of the present invention.

[0029] In this application, terms such as "comprising" or "having" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Furthermore, when a part such as a layer, film, region, or plate is described as being "on" another part, this includes not only the case where it is "immediately above" the other part, but also the case where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "under" another part, this includes not only the case where it is "immediately below" the other part, but also the case where there is another part in between. Additionally, in this application, being "placed on" may include being placed on the lower part as well as on the upper part.

[0031] The present invention will be described in detail below.

[0032] FIG. 2 is a flowchart showing the sequence of the method for manufacturing an electrode according to the present invention.

[0033] Referring to FIG. 2, a method for manufacturing an electrode according to the present invention comprises the steps of: forming a dam line coating layer having a predetermined width on a current collector and surrounding a region to be coated with an electrode slurry (S10); forming an electrode composite layer by coating an electrode slurry within the region surrounded by the dam line coating layer (S11); and drying the current collector on which the dam line coating layer and the electrode composite layer are formed (S12).

[0034] As previously explained, during the process of coating the electrode slurry onto the current collector, variations may occur in the amount of electrode slurry discharged along the width direction, and as the coated electrode slurry spreads out due to gravity, the width and length of the electrode composite layer may become uneven. Furthermore, due to the above phenomena, variations in thickness may occur between the edges and the center of the electrode composite layer.

[0035] Accordingly, the present invention can minimize variations in width, length, and thickness of the electrode composite layer by pre-forming a dam line coating layer surrounding the area to be coated of the electrode slurry before coating the electrode slurry.

[0037] Each step of the method for manufacturing an electrode according to the present invention will be described in detail below.

[0038] Formation of the dam line coating layer

[0039] FIGS. 3 and FIGS. 4 are schematic diagrams showing the structure of an electrode (100) according to the present invention. FIGS. 4 (a) shows the top view of FIGS. 3, and FIGS. 4 (b) shows the cross-section of FIGS. 3.

[0040] Referring to FIGS. 3 and FIGS. 4 together with FIGS. 2, a dam line coating layer (130) is first formed on the current collector (110).

[0041] The above current collector (110) may be a positive current collector or a negative current collector.

[0042] In the present invention, the positive current collector is generally made with a thickness of 3 to 500 μm. Such a positive current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery, and for example, stainless steel, aluminum, nickel, titanium, calcined carbon, or aluminum or stainless steel surface-treated with carbon, nickel, titanium, silver, etc. may be used. The current collector may also form fine irregularities on its surface to increase the adhesion of the positive active material, and various forms such as films, sheets, foils, nets, porous bodies, foams, and nonwoven fabrics are possible.

[0043] In the case of the negative electrode current collector, it is generally made with a thickness of 3 to 500 μm. Such a negative electrode current collector is not particularly limited as long as it is conductive without causing chemical 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., and aluminum-cadmium alloy may be used. In addition, similar to the positive electrode current collector, fine irregularities may be formed on the surface to strengthen the bonding strength of the negative electrode active material, and it may be used in various forms such as films, sheets, foils, nets, porous bodies, foams, and nonwoven fabrics.

[0044] Meanwhile, the dam line coating layer (130) is a frame shape that surrounds the area where the electrode composite layer (120) is formed. Accordingly, the shape and size of the area surrounded by the dam line coating layer (130) are the same as the shape and size of the electrode composite layer (120), and shapes such as circular, rectangular, and square are possible.

[0045] That is, the present invention can prevent the phenomenon in which the thickness of the electrode slurry at the edges decreases due to gravity flowing down before drying by pre-forming the dam line coating layer (130) and filling the space inside the dam line coating layer with electrode slurry. In addition, it can prevent imbalances in the length and width of the electrode composite layer caused by fine shaking of the coating die or differences in the amount of liquid ejected in the width direction during the electrode slurry coating process. In particular, the present invention has the advantage of improving the performance of the electrode by preventing the electrode slurry from flowing down even when the thickness of the electrode composite layer (120) is increased to increase the capacity of the electrode.

[0046] Specifically, the dam line coating layer (130) can be formed in various ways, but in detail, it can be formed by coating a dam line forming slurry around the perimeter of the area where the electrode slurry is coated, that is, around the perimeter of the area where the electrode composite layer (120) is formed. The dam line forming slurry may include a polymer constituting the body of the dam line, a solvent in which the polymer is dispersed, and a binder that exerts adhesive force so that the polymer can be attached to the current collector.

[0047] At this time, the slurry for forming the dam line can be coated on a current collector through one or more methods selected from the group consisting of spray coating, roll coating, die coating, gravure printing, and bar coating. More specifically, the dam line coating layer (130) can be formed using the same method as the electrode slurry coating method, thereby enabling a continuous process compared to other processes such as deposition, and reducing the time and cost required to form the dam line coating layer (130).

[0048] However, when the dam line coating layer (130) is formed by slurry coating in this manner, the same problem may occur before drying as the slurry for forming the dam line flows down due to gravity, just like the electrode slurry. For example, the thickness of the dam line coating layer (130) may gradually decrease towards the edges. If such a thickness variation is severe, the thickness of the part where the electrode composite layer (120) contacts the dam line coating layer (130) decreases towards the edges, so the objective of the present invention cannot be achieved. Therefore, the present invention can make the thickness of the electrode composite layer (120) that contacts the dam line coating layer (130) uniform by making the thickness of the dam line coating layer (130) as uniform as possible.

[0049] The width and thickness of the dam line coating layer (130) can be appropriately adjusted according to the electrode to be manufactured. For example, the thickness of the dam line coating layer (130) may be the same as the thickness of the electrode composite layer (120). This prevents the formation of a space surrounded by the dam line coating layer (130), the electrode composite layer (120), and the separator between the electrode and the separator when manufacturing the electrode assembly, and allows the electrode composite layer (120) and the separator to be completely in contact.

[0050] FIG. 5 is a schematic diagram showing the structure of an electrode according to one embodiment of the present invention.

[0051] Referring to FIG. 5, the angle (θ) formed between the surface of the dam line coating layer (130) and the current collector (110) may be 60 to 90°, and more specifically, 70 to 90°. Here, the angle formed between the surface of the dam line coating layer (130) and the current collector (110) is a concept identical to the contact angle, and refers to the angle including the dam line coating layer (130) among the angles formed between the surface of the current collector (110) and the cut line at the contact point of the three phases of air, the current collector, and the dam line coating layer when the dam line coating layer (130) is on the current collector (110). The present invention can minimize thickness variation at the edge portion of the electrode composite layer (120) by maximizing the angle formed between the surface of the dam line coating layer (130) and the current collector (110).

[0052] To this end, the polymer, solvent, and binder included in the slurry for forming the dam line may be hydrophobic. By using a hydrophobic polymer in the slurry for forming the dam line, the angle formed between the surface of the dam line coating layer (130) and the current collector (110) can be increased. This is the same principle as the contact angle between a solid and a liquid increasing. The contact angle is related to the affinity between the liquid phase material and the solid phase material. For example, if the liquid phase material is affine with the solid phase material (high affinity), the liquid phase material spreads widely on the solid phase material, which means that the surface free energy of the solid phase material is high. Conversely, if the liquid phase material is not affine with the solid phase material, the contact area between the liquid phase material and the solid phase material becomes small, which means that the surface free energy of the solid phase material is low. In the present invention, since the current collector (110) is a metal, it is relatively hydrophilic due to the free electrons inside it. Accordingly, by using a hydrophobic polymer in the slurry for forming the dam line, the contact angle between the dam line coating layer (130) and the current collector (110) can be increased without a separate structure. Likewise, the solvent used in the slurry for forming the dam line can also be a hydrophobic solvent to easily disperse the polymer and increase the contact angle between the dam line coating layer (130) and the current collector.

[0053] Furthermore, the polymer included in the slurry for forming the dam line may be an insulating polymer. Generally, the edges of the electrode composite layer (120) may be coated with an insulating material or have insulating tape attached to prevent the positive and negative electrodes from coming into contact and short-circuiting. In the present invention, a polymer used for insulating coating may be used as the polymer included in the slurry for forming the dam line so that the dam line coating layer (130) performs the role of an insulating coating layer.

[0054] Such polymers may be selected from the group including, for example, polybutadiene, polyurethane, polyimide, polyester, polycarbonate, polyphenylenesulfide (PPS), polyolefin, polydimethylsiloxane (PDMS), styrene-butadiene copolymer, (meth)acrylate, polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), and mixtures thereof, but are not limited thereto.

[0055] FIG. 6 is a schematic diagram showing the manufacturing process of an electrode according to another embodiment of the present invention.

[0056] Referring to FIG. 6, a separate guide member (140) may be used to form a dam line coating layer (130). The guide member (140) serves as a frame to fix the shape of the dam line coating layer (130). In this case, the guide member (140) is placed on the current collector (110) as shown in FIG. 6. The guide member (140) is positioned to surround the area where the dam line coating layer (130) is formed, and may include a first guide member (141) surrounding the outside of the area where the dam line coating layer (130) is formed and a second guide member (142) located inside the area where the dam line coating layer (130) is formed. The slurry for forming the dam line may be filled into the area surrounded by the guide member (140), that is, the area formed between the first guide member (141) and the second guide member (142). When using the guide member (140) in this manner, it is possible to prevent the shape of the dam line coating layer (130) from collapsing before the electrode slurry coating, maintain the angle between the surface of the dam line coating layer (130) and the current collector at 90°, and use the polymer included in the slurry for forming the dam line without limitation. Similarly, by using an insulating polymer included in the slurry for forming the dam line, the dam line coating layer (130) can be made to perform the role of an insulating coating layer.

[0057] Meanwhile, a drying process may be performed after the dam line coating layer (130) is formed. At this time, as described below, the drying of the dam line coating layer (130) may be performed simultaneously with the drying of the electrode composite layer (120), or the dam line coating layer (130) may be dried first before the formation of the electrode composite layer (120). In particular, when a guide member (140) is used, the guide member (140) is removed before the formation of the electrode composite layer (120). By drying the dam line coating layer (130) surrounded by the guide member (140) before that, the shape of the dam line coating layer (130) can be prevented from being deformed during the removal process of the guide member (140).

[0059] Application and Drying of Electrode Slurry

[0060] When the formation of the dam line coating layer (130) is completed, an electrode slurry is coated on the current collector (110) to form an electrode composite layer (120). This process can be performed by filling the electrode slurry into the area surrounded by the dam line coating layer (130).

[0061] The electrode slurry may include an electrode active material, a conductive material, and a binder. The electrode active material may be a negative electrode active material or a positive electrode active material.

[0062] In the present invention, the positive electrode active material is a material capable of causing an electrochemical reaction, and is a lithium transition metal oxide comprising two or more transition metals, for example, a layered compound such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2) substituted with one or more transition metals; lithium manganese oxide substituted with one or more transition metals; and the chemical formula LiNi 1-y M y Lithium nickel-based oxide represented by O2 (wherein M = Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn, or Ga and contains one or more of the above elements, 0.01≤y≤0.7); Li1+z Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2, Li 1+z Ni 0.4 Mn 0.4 Co 0.2 Li, like O2, etc. 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A e A lithium nickel cobalt manganese composite oxide represented by (where -0.5≤z≤0.5, 0.1≤b≤0.8, 0.1≤c≤0.8, 0≤d≤0.2, 0≤e≤0.2, b+c+d<1, M = Al, Mg, Cr, Ti, Si or Y, and A = F, P or Cl); chemical formula Li 1+x M 1-y M' y PO 4-z X z Examples include olivine-based lithium metal phosphates expressed as (where M = transition metal, preferably Fe, Mn, Co, or Ni, M' = Al, Mg, or Ti, X = F, S, or N, and -0.5≤x≤+0.5, 0≤y≤0.5, 0≤z≤0.1), but are not limited to these.

[0063] The cathode active material is carbon, for example, non-graphitizable carbon, graphite-based carbon, etc.; Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1), Sn x Me 1-x Me y O z(Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, Group 1, 2, and 3 elements of the periodic table, halogens; 0 <x≤1; 1≤y≤3; 1≤z≤8) 등의 금속 복합 산화물; 리튬 금속; 리튬 합금; 규소계 합금; 주석계 합금; SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5등의 금속 산화물; 폴리아세틸렌 등의 도전성 고분자; Li-Co-Ni 계 재료 등을 사용할 수 있다.

[0064] The above conductive material is typically added in an amount of 1 to 30 weight percent based on the total weight of the mixture containing the positive electrode active material. Such conductive material is not particularly limited as long as it is conductive without causing chemical changes in the battery, and 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, or thermal black; conductive fibers such as carbon fibers or metal fibers; metal powders such as carbon fluoride, aluminum, or nickel powder; conductive whiskey such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; or conductive materials such as polyphenylene derivatives may be used.

[0065] The above binder is a component that assists in the bonding of the active material and the conductive material, and in the bonding to the current collector, and is typically added in an amount of 1 to 30 weight percent based on the total weight of the mixture containing the positive 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, fluororubber, and various copolymers.

[0066] Meanwhile, such an electrode slurry can be prepared by dissolving an electrode active material, a conductive material, and a binder in a solvent. There are no specific restrictions on the type of solvent as long as it is capable of dispersing the electrode active material, and both aqueous and non-aqueous solvents may be used. For example, the solvent may be a solvent generally used in the relevant technical field and may be dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, or water, and one of these alone or a mixture of two or more may be used. The amount of solvent used is not particularly limited, provided that it is sufficient to allow the slurry to have an appropriate viscosity by considering the coating thickness, manufacturing yield, and workability of the slurry.

[0067] Once the electrode slurry is coated in this manner, a drying process can be performed. The drying can be carried out using known methods, for example, an oven. The oven provides a space in the shape of a chamber where the electrode is dried, so that the electrode to be dried is temporarily accommodated during the drying process, and internal heat can be prevented from escaping to the outside for drying. The oven may be equipped with a hot air nozzle or an infrared heater inside for drying the electrode.

[0068] FIGS. 7 and FIGS. 8 are flowcharts showing the sequence of a method for manufacturing an electrode according to another embodiment of the present invention.

[0069] In one example, the dam line coating layer may be dried together with the electrode composite layer. That is, the method for manufacturing an electrode comprises the steps of: forming a dam line coating layer having a predetermined width on a current collector as shown in FIG. 7 and having a shape that surrounds a coating area of ​​the electrode slurry (S20); forming an electrode composite layer by coating the electrode slurry within the area surrounded by the dam line coating layer (S21); and drying the dam line coating layer and the electrode composite layer simultaneously (S22). That is, the dam line coating layer is dried after the electrode composite layer is formed.

[0070] In this way, when the drying of the dam line coating layer is carried out together with the electrode composite layer after the formation of the electrode composite layer, a mixed phase is formed at the interface between the dam line coating layer and the electrode composite layer in which the dam line coating layer and the electrode composite layer are mixed with each other, thereby enabling the dam line coating layer and the electrode composite layer to bond strongly together. Additionally, since an intermediate drying process is not performed, there is an advantage of saving time and cost.

[0071] In another example, the dam line coating layer may be dried before the formation of the electrode composite layer. That is, the method for manufacturing the electrode comprises the steps of: forming a dam line coating layer having a predetermined width as shown in FIG. 8 and having a shape that surrounds the area to be coated with the electrode slurry (S30); drying the dam line coating layer (S31); coating the electrode slurry within the area surrounded by the dam line coating layer to form an electrode composite layer (S32); and drying the electrode composite layer (S33).

[0072] In this way, if a dam line coating layer is formed before the formation of the electrode composite layer, it is possible to prevent the dam line coating layer from collapsing before the formation and drying of the electrode composite layer. At this time, by partially drying the dam line coating layer, the effect of the dam line coating layer and the electrode composite layer being strongly bonded to each other can be achieved simultaneously.

[0074] In addition, the present invention provides an electrode.

[0075] Referring to FIGS. 2 to 4, the electrode (100) according to the present invention is manufactured by the method of manufacturing an electrode as described above, and has a structure comprising a current collector (110); an electrode composite layer (120) formed on the current collector (110); and a dam line coating layer (130) surrounding the electrode composite layer (120). Due to the dam line coating layer (130) surrounding the electrode composite layer (120), the thickness, width, and length of the electrode composite layer (120) according to the present invention can be uniformly formed across the entire surface of the electrode composite layer (120).

[0076] Specifically, the angle formed by the surface of the dam line coating layer (130) with the current collector (110) may be 60 to 90°, and more specifically, 70 to 90°.

[0077] In addition, the polymer, solvent, and binder included in the dam line coating layer (130) may be hydrophobic, and the polymer may be insulating.

[0078] Specifically, the polymer included in the dam line coating layer (130) may be selected from the group comprising polybutadiene, polyurethane, polyimide, polyester, polycarbonate, polyphenylenesulfide (PPS), polyolefin, polydimethylsiloxane (PDMS), styrene-butadiene copolymer, (meth)acrylate, polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), and mixtures thereof.

[0079] At this time, the thickness of the dam line coating layer (130) may be the same as the thickness of the electrode composite layer.

[0081] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the drawings disclosed in this invention are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by these drawings. The scope of protection of the present invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention.

[0083] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back have been used in this specification, these terms are used merely for convenience of explanation, and it is obvious that they may vary depending on the location of the object or the position of the observer. Explanation of the symbols

[0085] 1, 100: Electrode 10, 110: Entire house 20, 120: Electrode composite layer 130: Dam line coating layer 140: Absence of guide 141: First guide absence 142: Absence of 2nd guide

Claims

Claim 1 A method for manufacturing an electrode comprising: a step of forming a dam line coating layer having a predetermined width on a current collector and surrounding an area to be coated with an electrode slurry; a step of forming an electrode composite layer by coating an electrode slurry within an area surrounded by the dam line coating layer; and a step of drying the electrode composite layer, wherein the dam line coating layer is formed by coating a dam line forming slurry around the perimeter of an area to be coated with an electrode slurry, and the dam line coating layer is formed by arranging a guide member surrounding an area to be formed with the dam line coating layer on a current collector, filling a dam line forming slurry into an area surrounded by the guide member, and drying the dam line forming slurry surrounded by the guide member. Claim 2 delete Claim 3 A method for manufacturing an electrode according to claim 1, wherein the angle formed by the surface of the dam line coating layer with the current collector is 60 to 90°. Claim 4 A method for manufacturing an electrode in which the polymer, solvent, and binder included in the slurry for forming the dam line are hydrophobic, according to claim 1. Claim 5 A method for manufacturing an electrode according to claim 4, wherein the polymer included in the slurry for forming the dam line is insulating. Claim 6 A method for manufacturing an electrode according to claim 4, wherein the polymer included in the slurry for forming the dam line is selected from the group comprising polybutadiene, polyurethane, polyimide, polyester, polycarbonate, polyphenylenesulfide (PPS), polyolefin, polydimethylsiloxane (PDMS), styrene-butadiene copolymer, (meth)acrylate, polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), and mixtures thereof. Claim 7 delete Claim 8 A method for manufacturing an electrode in which the thickness of the dam line coating layer is the same as the thickness of the electrode composite layer, in claim 1. Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 An electrode having a structure formed by the method for manufacturing an electrode according to claim 1, comprising: a current collector; an electrode composite layer formed on the current collector; and a dam line coating layer surrounding the electrode composite layer.

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