Electrode sheet manufacturing device and electrode sheet manufacturing method using the same

Abstract

The present invention relates to an electrode sheet manufacturing device and an electrode sheet manufacturing method using the same, which include: a rewinder that winds up metal foil; a first coating member located behind the rewinder that applies a first coating material to a predetermined area of ​​the metal foil; and a second coating member located between the rewinder and the first coating member that applies a second coating material including an electrode active material, wherein the applied first coating material and the applied second coating material do not overlap, and which can prevent the occurrence of a sliding portion on the outer periphery of the electrode.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0187010, filed December 20, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an electrode sheet manufacturing apparatus and an electrode sheet manufacturing method using the same, and more particularly to an electrode sheet manufacturing apparatus that can prevent the occurrence of a sliding portion in a landed portion that is an electrode mixture layer coated on a metal foil, and an electrode sheet manufacturing method using the same. [Background technology]

[0003] Rechargeable lithium secondary batteries are widely used as energy sources for wireless mobile devices or wearable devices, as well as for electric vehicles and hybrid electric vehicles, which are presented as alternatives to existing gasoline and diesel vehicles that cause air pollution.

[0004] In order to mass-produce the lithium secondary battery, an electrode sheet is manufactured and then divided to manufacture electrodes.

[0005] A typical process for manufacturing an electrode sheet includes coating an electrode active material on the surface of the electrode sheet except for the portion where the electrode tab is to be formed, and drying and rolling the electrode active material. To manufacture an electrode using the electrode sheet manufactured in this manner, the electrode sheet may be slit and the slit electrode sheet may be notched.

[0006] The electrode of the lithium secondary battery includes a coated portion where an electrode active material is coated on one or both sides of the electrode plate, and an uncoated portion where the electrode active material is not coated, and an electrode tab may be formed on the uncoated portion.

[0007] During the manufacturing process of the electrode sheet, a phenomenon in which the outer periphery of the electrode mixture coated on the surface thereof flows before drying, and this region is called a slide region. When an electrode is manufactured using an electrode sheet including a slide region, which is a region where the thickness of the electrode mixture decreases, and then the electrode is laminated with a separator, a phenomenon in which the electrode and the separator are not adhered to each other and float up can occur.

[0008] This phenomenon can slow down the speed of lithium ions passing through the separator, causing negative electrode overpotential, and can deepen the imbalance in the lithium salt concentration in the electrolyte, accelerating electrolyte decomposition and causing the electrolyte to be quickly depleted, which can result in lithium precipitation.

[0009] To solve this problem, a method was attempted in which a CPP film was attached to the sliding portion of the electrode to compensate for the thickness reduction, but this did not completely solve the above problems.

[0010] Alternatively, an etching process has been developed in which the sliding portion is removed using a laser during the process of coating the electrode active material. However, as the thickness of the electrode active material becomes thinner, the process becomes more difficult and fine pinholes may occur, which may affect the quality of the electrode.

[0011] Patent Document 1 discloses a method of forming an electrode mixture layer by forming a dam line coating layer in a shape that surrounds an area to be coated with electrode slurry, and coating the electrode slurry within the area surrounded by the dam line coating layer.

[0012] In Patent Document 1, a dam line coating layer is formed on the edge of the electrode slurry to prevent the electrode slurry from flowing, thereby preventing the occurrence of sliding portions. However, since the process of forming the dam line coating layer and the process of coating the electrode slurry must be performed separately, the process time may increase, and the process of filling the dam line coating layer with the electrode slurry must be performed carefully.

[0013] Patent Document 2 relates to an electrode having a binder layer and a manufacturing method thereof, in which an electrode active material layer is formed on a current collector having an electrode tab formed on one end thereof, and a binder layer is formed between the current collector and the electrode active material layer, and the binder layer is formed on both ends of the electrode active material layer.

[0014] In Patent Document 2, prior to applying the electrode slurry, a binder composition is applied to both ends of the position where the electrode slurry will be applied, thereby preventing the electrode slurry from being detached from the current collector during the notching process of the current collector.

[0015] That is, Patent Document 2 cannot provide a technique for preventing the formation of a sliding portion in the electrode active material layer.

[0016] Therefore, there is a need for a technology that can prevent problems such as electrolyte depletion and lithium deposition by preventing the formation of a sliding portion at the outer periphery of a land portion coated with an electrode active material and by bonding the electrode and separator to each other at the entire interface, and that can be performed in a continuous process so as not to delay the electrode manufacturing process. [Prior art documents] [Patent documents]

[0017] [Patent Document 1] Korean Patent Publication No. 10-2023-0006265 [Patent Document 2] Korean Patent Publication No. 10-2023-0061044 Summary of the Invention [Problem to be solved by the invention]

[0018] The present invention has been made to solve the above-mentioned problems, and aims to provide an electrode sheet manufacturing device in which a slide portion is not formed on the outer periphery of a ground portion coated with an electrode mixture, and an electrode sheet manufacturing method using the same. [Means for solving the problem]

[0019] To achieve this object, the electrode sheet manufacturing apparatus according to the present invention includes a rewinder (200) that winds up a metal foil (110), a first coating member (300) that is located behind the rewinder (200) and applies a first coating material (330) to a predetermined area of ​​the metal foil (110), and a second coating member (400) that is located between the rewinder (200) and the first coating member (300) and applies a second coating material (430) containing an electrode active material, wherein the applied first coating material (330) and the second coating material (430) do not overlap.

[0020] The first coating material (330) may include a hydrophobic material.

[0021] The first coating material (330) may include a volatile material.

[0022] A drying member (500) for volatilizing the first coating material (330) may be further included between the rewinder (200) and the second coating member (400).

[0023] The first coating member (300) and the second coating member (400) may be slot dies.

[0024] The first coating member (300) may include one or more first nozzles (310) and a first coating material supply unit (320) for supplying the first coating material (330) to the first nozzles (310), and the second coating member (400) may include one or more second nozzles (410) and a second coating material supply unit (420) for supplying the second coating material (430) to the second nozzles (410).

[0025] The first nozzle (310) and the second nozzle (410) are each one, and the first nozzle (310) and the second nozzle (410) may be positioned so as not to overlap with each other when viewed in the longitudinal direction x of the metal foil (110).

[0026] The first nozzle (310) may be one, and the second nozzles (410) may be two, and the first nozzle (310) and the second nozzle (410) may be positioned so as not to overlap with each other when viewed in the longitudinal direction x of the metal foil (110).

[0027] Each of the first nozzles (310) and the second nozzles (410) includes a plurality of nozzles spaced apart at regular intervals along the width direction y of the metal foil (110), and the first nozzles (310) and the second nozzles (410) may be positioned so as not to overlap with each other when viewed in the length direction x of the metal foil (110).

[0028] The second coating material (430) may include a hydrophilic material.

[0029] The present invention provides a method for manufacturing an electrode sheet using the electrode sheet manufacturing apparatus, which includes a first step of supplying a metal foil (110), a second step of coating the metal foil (110) with a first coating material (330) including a hydrophobic material, and a third step of coating the metal foil (110) with a second coating material (430) including an electrode active material, and the first coating material (330) and the second coating material (430) may be applied continuously along a longitudinal direction x of the metal foil (110).

[0030] The first coating material (330) and the second coating material (430) may not overlap.

[0031] After the third step, a fourth step of drying the metal foil (110) coated with the first coating material (330) and the second coating material (430) may be further included.

[0032] In the second step, the first coating material (330) may be a plurality of pieces spaced apart from each other along the width direction y of the metal foil (110).

[0033] The second coating material (430) may include a hydrophilic material.

[0034] Furthermore, the present invention can also be provided in the form of various combinations of means for solving the above problems. [Effects of the Invention]

[0035] As described above, according to the electrode sheet manufacturing apparatus and the electrode sheet manufacturing method using the same of the present invention, when a first coating material containing a hydrophobic material is applied to a predetermined region of a metal foil and a second coating material containing a hydrophilic material is applied to the remaining region where the first coating material is not applied, the first coating material can function as a blocking dam that blocks the flow of the second coating material, thereby preventing the occurrence of a sliding portion at the outer periphery of the second coating material.

[0036] In addition, according to the electrode sheet manufacturing apparatus and the electrode sheet manufacturing method using the same of the present invention, the first coating material contains a volatile substance, which may be volatilized and removed during the drying process of the electrode sheet, and therefore there is an advantage in that a separate device or process for removing the first coating material is not required.

[0037] In addition, the electrode manufactured by the electrode sheet manufacturing apparatus and the electrode sheet manufacturing method using the same according to the present invention has no sliding portion in the coating portion, so the entire area facing the separator can adhere to the separator, which can prevent depletion of the electrolyte and precipitation of lithium ions. [Brief explanation of the drawings]

[0038] [Figure 1] 1 is a perspective view of an electrode sheet manufacturing apparatus according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a perspective view of an electrode sheet manufacturing apparatus according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a perspective view of an electrode sheet manufacturing apparatus according to a third embodiment of the present invention. [Figure 4] 4A and 4B are cross-sectional views taken along lines AA', BB', CC' and DD' in FIG. 3, respectively. [Figure 5] FIG. 10 is a perspective view of an electrode sheet manufacturing apparatus according to a fourth embodiment of the present invention. [Figure 6] FIG. 10 is a perspective view of an electrode sheet manufacturing apparatus according to a fifth embodiment of the present invention. [Figure 7] 1 is a flowchart of an electrode sheet manufacturing method of the present invention. [Figure 8] FIG. 2 is a plan view of an electrode sheet manufactured using the electrode sheet manufacturing apparatus according to the first embodiment, illustrating the electrode formation process. [Figure 9] FIG. 10 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing apparatus according to a second embodiment, illustrating the electrode formation process. [Figure 10]FIG. 10 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing apparatus according to a third embodiment, illustrating the electrode formation process. [Figure 11] FIG. 10 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing apparatus according to a third embodiment, illustrating the process of forming electrodes of other shapes. [Figure 12] FIG. 10 is a plan view of a deformed electrode sheet, illustrating the process of forming electrodes. DETAILED DESCRIPTION OF THE INVENTION

[0039] Hereinafter, with reference to the accompanying drawings, a detailed description will be given of an embodiment of the present invention that will enable a person skilled in the art to easily carry out the present invention. In describing the operation principle of the embodiment of the present invention in detail, detailed description of related well-known functions or configurations will be omitted if it is determined that such detailed description may unnecessarily obscure the gist of the present invention.

[0040] Throughout the drawings, the same reference numerals are used for parts having similar functions and actions. Throughout the specification, when a part is said to be connected to another part, this includes not only a direct connection but also an indirect connection via another element therebetween. Furthermore, unless otherwise specified, "including a certain element" does not mean that other elements are excluded, but that other elements may also be included.

[0041] Descriptions that limit or specify additional elements are applicable to all inventions and are not limited to a particular invention unless otherwise limited.

[0042] Throughout the description and claims of this invention, the singular includes the plural unless otherwise stated.

[0043] Throughout the description and claims, "or" includes "and" unless otherwise stated. Thus, "comprising A or B" means the three cases of including A, including B, or including both A and B.

[0044] In this specification, the metal foil is configured in a sheet shape and is the target onto which the first coating material and the second coating material are applied.

[0045] The electrode sheet is defined as a metal foil that has been coated with at least one of the first and second coating materials but has not yet been slit.

[0046] The electrode mixture contains a positive electrode active material or a negative electrode active material, a conductive material, a binder, a solvent, and an additive, and is used as a concept including an electrode slurry, which is the state of the electrode mixture before it is dried.

[0047] The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG.

[0048] FIG. 1 is a perspective view of an electrode sheet manufacturing apparatus according to a first embodiment of the present invention.

[0049] As shown in FIG. 1, the electrode sheet manufacturing apparatus according to the first embodiment includes an unwinder 100 that unwinds a metal foil 110, a rewinder 200 that winds up the metal foil 110, a first coating member 300 that applies a first coating material 330 to a predetermined region of the metal foil 110 unwound from the unwinder 100, a second coating member 400 that applies a second coating material 430 containing an electrode active material, and a drying member 500 that volatilizes the first coating material 330.

[0050] More specifically, the unwinder 100 and the rewinder 200 are configured to transport the wound metal foil 110 continuously or intermittently in one direction.

[0051] The first coating member 300 includes a first nozzle 310 positioned at the center of the width direction y of the metal foil 110 so that the first coating material 330 can be continuously coated along the longitudinal direction x of the metal foil 110, and a first coating material supply unit 320 for supplying the first coating material 330 to the first nozzle 310.

[0052] Here, the first coating material 330 may include a hydrophobic polymer, a hydrophobic solvent, and a volatile substance, and the hydrophobic polymer may be at least one selected from the group consisting of polybutadiene, polyurethane, polyimide, polyester, polycarbonate, polyphenylenesulfide (PPS), polyolefin, polydimethylsiloxane (PDMS), styrene-butadiene copolymer, (meth)acrylate, polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), and mixtures thereof.

[0053] The hydrophobic solvent may be at least one selected from the group consisting of propanol, butanol, pentanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, glycerol, and mixtures thereof.

[0054] The second coating member 400, located between the rewinder 200 and the first coating member 300, includes two second nozzles 410 and a second coating material supply unit 420 for supplying a second coating material 430 to the second nozzles 410.

[0055] Here, it is preferable that the second nozzle 410 is positioned so as not to overlap with the first nozzle 310 based on the longitudinal direction x, so as to minimize overlap between the first coating material 330 and the second coating material 430 and to continuously coat the second coating material 430 along the longitudinal direction x of the metal foil 110.

[0056] The second coating material 430 is an electrode mixture containing an electrode active material, a binder, a conductive material, an additive, and a solvent, which may include a hydrophilic material.

[0057] For example, a polar solvent corresponds to the hydrophilic solvent constituting the second electrode active material 430, and a representative hydrophilic solvent is water. In addition, the hydrophilic binder may include at least one hydrophilic monomer selected from the group consisting of (meth)acrylic acid, itaconic acid, sodium p-styrenesulfonate, sodium vinylsulfonate, sodium arylsulfonate, sodium 2-methylarylsulfonate, sodium ethyl methacrylate sulfonate, (meth)acrylamide, N-methylolacrylamide, N,N-dimethylacrylamide, and 2-acrylamido-2-methylpropanesulfonic acid.

[0058] The electrode active material may include a conventional positive electrode active material and a negative electrode active material for a lithium secondary battery, and the type thereof is not limited.

[0059] Meanwhile, the first nozzle 310 and the second nozzle 410 may be slot dies that can extrude and coat one side of the metal foil 110 with the first coating material 330 and the second coating material 430 supplied in the form of electrode slurries.

[0060] As described above, since the first coating material 330 includes a hydrophobic material while the second coating material 430 includes a hydrophilic material, even if a portion of the second coating material 430 is applied to the coating area of ​​the first coating material 330, the second coating material 430 can be prevented from being coated on the area where the first coating material 330 was applied, and therefore the second coating material 430 is coated only on the remaining area excluding the area where the first coating material 330 was applied.

[0061] The drying member 500 located between the second coating member 400 and the rewinder 200 is configured to volatilize the first coating material 330 and dry the second coating material 430 .

[0062] Specifically, since the metal foil 110 to which the first coating material 330 and the second coating material 430 are applied is dried while passing through the drying member 500, the drying member 500 may be configured in the form of a chamber inside through which the metal foil 110 can pass, or may be configured in a form in which the upper and lower surfaces of the metal foil 110 are heated and dried, respectively.

[0063] As described above, in the present invention, the drying processes of the first coating material 330 and the second coating material 430 are performed simultaneously, which simplifies the manufacturing process and reduces manufacturing costs compared to performing these drying processes separately.

[0064] As described above, an electrode sheet is produced on the metal foil 110 that has passed through the drying member 500, with a plain portion where the first coating material 330 has been removed and a coated portion where the second coating material 430 has been coated.

[0065] Although not shown in FIG. 1, a support (not shown) for supporting the metal foil 110 may be further disposed below the metal foil 110, and a first nozzle and a second nozzle may also be additionally disposed on the underside of the metal foil 110.

[0066] 2 is a perspective view of an electrode sheet manufacturing apparatus according to a second embodiment of the present invention. Referring to FIG. 2, the electrode sheet manufacturing apparatus according to the second embodiment is the same as that of the first embodiment except for the positions and the number of first nozzles 310 and second nozzles 410.

[0067] In detail, there are two first nozzles 310 for discharging the first coating material 330, each located at both ends of the metal foil 110 in the width direction y, while there is one second nozzle 410 for discharging the second coating material 430.

[0068] Of course, in order to minimize overlapping of the first coating material 330 and the second coating material 430, the first nozzle 310 and the second nozzle 410 are positioned so as not to overlap with each other based on the longitudinal direction x.

[0069] Figure 3 is a perspective view of an electrode sheet manufacturing apparatus according to a third embodiment of the present invention, and Figure 4 is a cross-sectional view taken along lines A-A', B-B', C-C', and D-D' in Figure 3. Referring to Figure 3, the electrode sheet manufacturing apparatus according to the third embodiment is the same as that of the first embodiment, except for the positions and number of first nozzles 310 and second nozzles 410.

[0070] In detail, the first nozzles 310 that eject the first coating material 330 consist of four nozzles, which are located at regular intervals between both ends of the width direction y of the metal foil 110, while the second nozzles 410 that eject the second coating material 430 consist of three nozzles along the width direction y of the metal foil 110.

[0071] Of course, in order to minimize overlapping of the first coating material 330 and the second coating material 430, the first nozzle 310 and the second nozzle 410 are positioned so as not to overlap with each other based on the longitudinal direction x.

[0072] Meanwhile, in Figure 4, (a) is a vertical cross-sectional view taken along line A-A' in Figure 3 before the metal foil 110 passes through the first coating member 300, (b) is a vertical cross-sectional view taken along line B-B' in Figure 3 after the metal foil 110 has passed through the first coating member 300 and been coated with the first coating material 330, (c) is a vertical cross-sectional view taken along line C-C' in Figure 3 after the metal foil 110 has passed through the second coating member 400 and been coated with the second coating material 430 between the first coating material 330, and (d) is a cross-sectional view taken along line D-D' in Figure 3 after the metal foil has passed through the drying member 500 and the first coating material 330 has been removed.

[0073] The first coating material 330 is applied to the metal foil 110 to prevent the second coating material 430 from flowing, so it is recommended to adjust the amount of the first coating material 330 dispensed so that the thickness D1 of the first coating material 330 is equal to or less than the thickness D2 of the second coating material 430.

[0074] Of course, since the first coating material 330 contains a volatile substance and can be removed by evaporation in the drying member 500, the thickness D1 of the first coating material 330 may be formed thicker than the thickness D2 of the second coating material.

[0075] Since the second coating material 430 is applied between the first coating materials 330, the first coating material 330 can act as a blocking dam that prevents the second coating material 430 from flowing. This prevents the formation of a slanted sliding portion at the outer periphery of the second coating material 430, and allows the second coating material 430 to maintain a consistent thickness across the entire area.

[0076] FIG. 5 is a perspective view of an electrode sheet manufacturing apparatus according to a fourth embodiment of the present invention.

[0077] Referring to FIG. 5, the electrode sheet manufacturing apparatus according to the fourth embodiment is substantially the same as that of the second embodiment, except for the outer shape.

[0078] More specifically, in the second embodiment, the first coating material 330 and the second coating material 430 are supplied from the side, while in the fourth embodiment, the first coating material 330 and the second coating material 430 are supplied from the top.

[0079] 6 is a perspective view of an electrode sheet manufacturing apparatus according to a fifth embodiment of the present invention. Referring to FIG. 6, the electrode sheet manufacturing apparatus according to the fifth embodiment is substantially the same as that of the third embodiment, except for its external shape.

[0080] More specifically, in the third embodiment, the first coating material 330 and the second coating material 430 are supplied from the side, while in the fifth embodiment, the first coating material 330 and the second coating material 430 are supplied from the top.

[0081] Next, a method for manufacturing an electrode sheet using the above-mentioned electrode sheet manufacturing apparatus will be described. Fig. 7 is a flowchart of the electrode sheet manufacturing method of the present invention, and Fig. 8 is a plan view of an electrode sheet manufactured using the electrode sheet manufacturing apparatus according to the first embodiment, illustrating the electrode formation process.

[0082] Referring to FIG. 7, a method for manufacturing an electrode sheet according to the present invention includes a first step of providing a metal foil, a second step of coating the metal foil with a first coating material including a hydrophobic material, a third step of coating the metal foil with a second coating material including an electrode active material, and a fourth step of drying the metal foil coated with the first and second coating materials.

[0083] As described above, the first coating material 330 and the second coating material 430 are applied continuously along the longitudinal direction of the metal foil 110, but the first coating material 330 and the second coating material 430 do not overlap each other, and the first coating material 330 volatilizes during the drying process.

[0084] Therefore, as shown in FIG. 8, the center of the electrode sheet 1000 in the width direction where the first coating material is applied is an uncoated portion, and the metal foil 110 is exposed, while coated portions where the second coating material 430 is applied are formed on both sides of the uncoated portion.

[0085] When an electrode is manufactured using the electrode sheet 1000 having the above-described shape, the electrode sheet 1000 is notched along the notching lines in the width direction of the electrode sheet 1000.

[0086] That is, the electrode sheet 1000 is slit in the width direction, and the middle portion where the metal foil 110 is exposed and the coating portion where the second coating material is applied are notched along the thick two-dot chain line, thereby obtaining a plurality of electrodes 1100 each having an electrode tab 1110 formed thereon.

[0087] 9 is a plan view of an electrode sheet manufactured using the electrode sheet manufacturing apparatus according to the second embodiment, illustrating the process of forming an electrode. Referring to FIG. 9, when the electrode sheet manufacturing apparatus according to the second embodiment is used, both side edges in the width direction of the electrode sheet 1000 where the first coating material is applied are uncoated portions, exposing the metal foil 110, and a coated portion where the second coating material 430 is applied is formed in the center between the uncoated portions.

[0088] When manufacturing electrodes using the electrode sheet 1000 having the above-described shape, the electrode sheet 1000 is slit along the longitudinal direction, and the uncoated and coated portions of both side edges where the metal foil 110 is exposed are notched along thick dashed double-dashed lines, thereby obtaining a large number of electrodes 1100 each having an electrode tab 1110 formed thereon.

[0089] 10 is a plan view of an electrode sheet manufactured using the electrode sheet manufacturing apparatus according to the third embodiment, illustrating the electrode formation process. Referring to FIG. 10, when the electrode sheet manufacturing apparatus according to the third embodiment is used, a total of four regions in the electrode sheet 1000, including both side edges in the width direction where the first coating material is applied, are uncoated portions, and the metal foil 110 is exposed, while a total of three regions in the center between the uncoated regions are coated with the second coating material 430 to form coated portions.

[0090] When manufacturing electrodes using the electrode sheet 1000 having the above-described shape, the electrode sheet 1000 is slit in the longitudinal direction, and the uncoated and coated portions where the metal foil 110 is exposed are notched along the thick two-dot chain lines, thereby obtaining a large number of electrodes 1100 each having an electrode tab 1110 formed thereon.

[0091] The electrode sheet 1000 in FIG. 10 is configured so that the notch lines indicated by thick two-dot chain lines have different sizes, so that two types of electrodes 1100 with different sizes can be manufactured.

[0092] 11 is a plan view of an electrode sheet manufactured using the electrode sheet manufacturing apparatus according to the third embodiment, illustrating a process for forming electrodes of other shapes. Referring to FIG. 11, when the electrode sheet manufacturing apparatus according to the third embodiment is used, a total of four regions of the electrode sheet 1000, including both side edges in the width direction where the first coating material is applied, are uncoated portions, and the metal foil 110 is exposed, while a total of three regions in the center between the uncoated portions are coated with the second coating material 430 to form coated portions.

[0093] When manufacturing electrodes using the electrode sheet 1000 having the above-described shape, the electrode sheet 1000 is slit in the longitudinal direction, and the uncoated and coated portions where the metal foil 110 is exposed are notched along the thick two-dot chain lines, thereby obtaining a large number of electrodes 1100 each having an electrode tab 1110 formed thereon.

[0094] 12 is a plan view of a modified electrode sheet, illustrating the electrode formation process. Referring to FIG. 12, the electrode sheet 1000 may be manufactured using an electrode sheet manufacturing apparatus having three first nozzles and three second nozzles arranged alternately. In the electrode sheet 1000, a total of three regions coated with the first coating material sprayed from the first nozzles are uncoated portions, exposing the metal foil 110, while the remaining three regions excluding the uncoated portions are coated with the second coating material 430 to form coated portions.

[0095] When manufacturing electrodes using the electrode sheet 1000 having the above-described shape, the electrode sheet 1000 is slit in the longitudinal direction, and the uncoated and coated portions where the metal foil 110 is exposed are notched along the thick two-dot chain lines, thereby obtaining a large number of electrodes 1100 each having an electrode tab 1110 formed thereon.

[0096] In an electrode manufactured by this process, a sliding portion is not formed in the coating portion where the electrode active material is coated, and therefore, when laminated on a separator, the electrode and separator do not lift up, thereby minimizing the conventional problems of increased resistance, electrolyte depletion, and lithium deposition.

[0097] Those skilled in the art will be able to make various applications and modifications within the scope of the present invention based on the above content. [Explanation of symbols]

[0098] 100 Unwinder 110 Metallic Foil 200 Rewinder 300 first coating member 310 No. 1 nozzle 320 First coating material supply unit 330 First coating material 400 second coating member 410 Second Nozzle 420 Second coating material supply unit 430 Second Coating Material 500 Drying material 1000 electrode sheets 1100 electrode 1110 Electrode tab D1 Thickness of the first coating material D2 Thickness of second coating material

Claims

1. A rewinder that winds up the metal foil; a first coating member positioned behind the rewinder and configured to apply a first coating material to a predetermined area of ​​the metal foil; a second coating member positioned between the rewinder and the first coating member, the second coating member applying a second coating material containing an electrode active material; The electrode sheet manufacturing apparatus, wherein the first coating material and the second coating material applied do not overlap.

2. The electrode sheet manufacturing apparatus according to claim 1 , wherein the first coating material includes a hydrophobic material.

3. The electrode sheet manufacturing apparatus according to claim 2 , wherein the first coating material includes a volatile material.

4. The electrode sheet manufacturing apparatus according to claim 3 , further comprising a drying member between the rewinder and the second coating member for volatilizing the first coating material.

5. The electrode sheet manufacturing apparatus according to claim 1 , wherein the first coating member and the second coating member are slot dies.

6. the first coating member includes one or more first nozzles and a first coating material supply unit for supplying the first coating material to the first nozzles; The electrode sheet manufacturing apparatus of claim 1 , wherein the second coating member includes one or more second nozzles and a second coating material supply unit for supplying the second coating material to the second nozzles.

7. 7. The electrode sheet manufacturing apparatus according to claim 6, wherein the first nozzle and the second nozzle are each one, and the first nozzle and the second nozzle are positioned so as not to overlap with each other when the longitudinal direction x of the metal foil is taken as a reference.

8. 7. The electrode sheet manufacturing apparatus according to claim 6, wherein the number of the first nozzles is one, the number of the second nozzles is two, and the first nozzles and the second nozzles are positioned so as not to overlap with each other when the longitudinal direction x of the metal foil is taken as a reference.

9. 7. The electrode sheet manufacturing apparatus of claim 6, wherein each of the first nozzle and the second nozzle includes a plurality of nozzles spaced apart at regular intervals along a width direction y of the metal foil, and the first nozzle and the second nozzle are positioned so as not to overlap with each other when viewed from a longitudinal direction x of the metal foil.

10. The electrode sheet manufacturing apparatus according to claim 1 , wherein the second coating material includes a hydrophilic material.

11. a first step of providing a metal foil; a second step of coating the metal foil with a first coating material comprising a hydrophobic material; and a third step of coating the metal foil with a second coating material including an electrode active material, The electrode sheet manufacturing method, wherein the first coating material and the second coating material are applied continuously along the longitudinal direction x of the metal foil.

12. The method for manufacturing an electrode sheet according to claim 11 , wherein the first coating material and the second coating material do not overlap.

13. The method of claim 11 , further comprising a fourth step of drying the metal foil coated with the first coating material and the second coating material after the third step.

14. The method of claim 12 , wherein in the second step, the first coating material is a plurality of pieces spaced apart from each other along a width direction y of the metal foil.

15. The method of manufacturing an electrode sheet according to claim 12 , wherein the second coating material includes a hydrophilic material.

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