Electrode sheet manufacturing device and electrode sheet manufacturing method using same

Abstract

The present invention relates to an electrode sheet manufacturing device and an electrode sheet manufacturing method using same, the device comprising: a rewinder for winding a metal foil; a first coating member which is located at the rear of the rewinder and which applies a first coating material to a predetermined area of the metal foil; and a second coating member which is located between the rewinder and the first coating member and which applies a second coating material that includes an electrode active material, wherein the applied first coating material and the second coating material do not overlap. A sliding part can be prevented from being generated on the exterior of an electrode.

Description

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

[0001] This application claims the benefit of priority to Korean Patent Application No. 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 device and a method for manufacturing an electrode sheet using the same. Specifically, the present invention relates to an electrode sheet manufacturing device capable of preventing the formation of a sliding part in a maintenance part, which is an electrode mixture layer coated on a metal foil, and to an electrode sheet manufacturing method using the same.

[0003]

[0004] Rechargeable lithium secondary batteries are widely used as energy sources for wireless mobile devices and wearable devices, and are also used as energy sources for electric vehicles and hybrid electric vehicles, which are presented as alternatives to existing gasoline and diesel vehicles that cause air pollution.

[0005] In order to mass-produce the above lithium secondary battery, an electrode sheet is manufactured, and then the electrode sheet is divided to manufacture an electrode.

[0006] A typical electrode sheet manufacturing process includes a step of coating an electrode active material on the surface of the electrode sheet, excluding the area where the electrode tabs will be formed, and a step of drying and rolling the electrode active material. To manufacture an electrode using the electrode sheet manufactured in this manner, a step of slitting the electrode sheet and a step of notching the slit electrode sheet can be performed.

[0007] The electrode of the above lithium secondary battery includes a support portion coated with an electrode active material on one or both sides of an electrode plate and a non-coated portion not coated with an electrode active material, and an electrode tab can be formed on the non-coated portion.

[0008] During the above electrode sheet manufacturing process, a phenomenon may occur in which the electrode mixture-coated maintenance portion flows down from the outer portion before drying. This region is called a sliding region. When an electrode is manufactured using an electrode sheet including a sliding region, which is a region in which the electrode mixture thickness is reduced, and the electrode is laminated together with a separator, a phenomenon in which the electrode and the separator do not adhere but lift off may occur.

[0009] This phenomenon can slow the passage of lithium ions through the separator, leading to the formation of an anode overpotential, exacerbating the imbalance in the lithium salt concentration in the electrolyte, and accelerating the decomposition of the electrolyte, rapidly depleting it. This, in turn, can result in lithium precipitation.

[0010] To solve this problem, a method of compensating for the thickness reduction by attaching a CPP film to the sliding part of the electrode was attempted, but the above problem was not completely solved.

[0011] Alternatively, an etching process is being developed to remove the sliding part using a laser during the process of coating the electrode active material, but as the thickness of the electrode active material becomes thinner, the process becomes more difficult, and fine pin holes, etc. may be created, which may affect the electrode quality.

[0012] Patent Document 1 discloses a method for forming an electrode mixture layer by forming a dam line coating layer having a shape surrounding an area to be coated with electrode slurry and coating electrode slurry within an area surrounded by the dam line coating layer.

[0013] Patent Document 1 can prevent the formation of a sliding part by forming a dam line coating layer on the edge of the electrode slurry to prevent the electrode slurry from flowing down, but since the process of forming the dam line coating layer and the electrode slurry coating process must be performed separately, the process time may increase, and the process of filling the electrode slurry into the dam line coating layer needs to be performed precisely.

[0014] Patent Document 2 relates to an electrode having a binder layer formed thereon and a method for manufacturing the same. The electrode comprises an electrode active material layer formed on a current collector having an electrode tab formed on one end thereof, wherein 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.

[0015] Patent Document 2 can prevent the electrode slurry from being detached from the current collector during the notching process of the current collector by applying a binder composition in advance to both ends of the position where the electrode slurry is to be applied before applying the electrode slurry.

[0016] That is, patent document 2 does not present a technology for preventing the formation of a sliding portion in the electrode active material layer.

[0017] Therefore, a technology is needed that can prevent problems such as electrolyte depletion and lithium precipitation by ensuring that the electrode and separator adhere to the entire interface without causing a sliding portion at the outer portion of the electrode active material-coated portion, and that can be performed as a continuous process so as not to delay the electrode manufacturing process.

[0018] (Prior art literature)

[0019] (Patent Document 1) Korean Patent Publication No. 2023-0006265 (January 10, 2023)

[0020] (Patent Document 2) Korean Patent Publication No. 2023-0061044 (May 8, 2023)

[0021]

[0022] The present invention is intended to solve the above-mentioned problem, and the purpose is to provide an electrode sheet manufacturing device that does not cause a sliding part on the outer part of a maintenance part coated with an electrode compound, and an electrode sheet manufacturing method using the same.

[0023]

[0024] To achieve this purpose, an electrode sheet manufacturing device according to the present invention includes a rewinder (200) for winding a metal foil (110), a first coating member (300) positioned at the rear of the rewinder (200) for applying a first coating material (330) to a predetermined area of ​​the metal foil (110), and a second coating member (400) positioned between the rewinder (200) and the first coating member (300) for applying a second coating material (430) containing an electrode active material, wherein the applied first coating material (330) and the second coating material (430) may not overlap.

[0025] The above first coating material (330) may include a hydrophobic material.

[0026] The above first coating material (330) may include a volatile material.

[0027] 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).

[0028] The first coating member (300) and the second coating member (400) may be slot dies.

[0029] 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).

[0030] The first nozzle (310) and the second nozzle (410) are each one, but the first nozzle (310) and the second nozzle (410) can be positioned so as not to overlap with each other when based on the longitudinal direction (x) of the metal foil (110).

[0031] The first nozzle (310) is one, and the second nozzle (410) is two, but the first nozzle (310) and the second nozzle (410) can be positioned so as not to overlap with each other when based on the longitudinal direction (x) of the metal foil (110).

[0032] The first nozzle (310) and the second nozzle (410) are each provided in a plurality spaced apart at a certain interval along the width direction (y) of the metal foil (110), but the first nozzle (310) and the second nozzle (410) may be positioned so as not to overlap with each other when based on the length direction (x) of the metal foil (110).

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

[0034] The present invention provides a method for manufacturing an electrode sheet using the above electrode sheet manufacturing device. Specifically, the method includes a first step of supplying a metal foil (110), a second step of coating a first coating material (330) containing a hydrophobic material on the metal foil (110), and a third step of coating a second coating material (430) containing an electrode active material on the metal foil (110), wherein the first coating material (330) and the second coating material (430) can be continuously applied along the longitudinal direction (x) of the metal foil (110).

[0035] The first coating material (330) and the second coating material (430) may not overlap.

[0036] 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.

[0037] In the second step, the first coating material (330) may be a plurality of pieces spaced apart along the width direction (y) of the metal foil (110).

[0038] The second coating material (430) may include a hydrophilic material.

[0039]

[0040] The present invention can also be provided in a form in which various means for solving the above problem are combined.

[0041]

[0042] As described above, according to the electrode sheet manufacturing device of the present invention and the electrode sheet manufacturing method using the same, when a first coating material including a hydrophobic material is applied to a predetermined area of ​​a metal foil and a second coating material including a hydrophilic material is applied to the remaining area where the first coating material is not applied, the first coating material can function as a barrier that blocks the second coating material from flowing down, thereby preventing a sliding portion from being formed on the outer portion of the second coating material.

[0043] In addition, according to the electrode sheet manufacturing device of the present invention and the electrode sheet manufacturing method using the same, the first coating material contains a volatile substance and can be removed by volatilization during the drying process of the electrode sheet, so there is an advantage in that a separate device or process for removing the first coating material is unnecessary.

[0044] In addition, since the electrode manufactured by the electrode sheet manufacturing device of the present invention and the electrode sheet manufacturing method using the same does not have a sliding portion in the coating portion, the entire area facing the separator can be adhered to the separator, which can prevent electrolyte depletion or lithium ion precipitation.

[0045]

[0046] FIG. 1 is a perspective view of an electrode sheet manufacturing device according to a first embodiment of the present invention.

[0047] Figure 2 is a perspective view of an electrode sheet manufacturing device according to a second embodiment of the present invention.

[0048] Figure 3 is a perspective view of an electrode sheet manufacturing device according to a third embodiment of the present invention.

[0049] Figure 4 is a cross-sectional view taken along lines A-A', B-B', CC', and D-D' of Figure 3, respectively.

[0050] Figure 5 is a perspective view of an electrode sheet manufacturing device according to a fourth embodiment of the present invention.

[0051] Fig. 6 is a perspective view of an electrode sheet manufacturing device according to a fifth embodiment of the present invention.

[0052] Figure 7 is a flow chart of the electrode sheet manufacturing method of the present invention.

[0053] Fig. 8 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to the first embodiment, and is a drawing for explaining the electrode formation process.

[0054] Fig. 9 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to the second embodiment, and is a drawing for explaining the electrode formation process.

[0055] Fig. 10 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to the third embodiment, and is a drawing for explaining the electrode formation process.

[0056] Fig. 11 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to the third embodiment, and is a drawing for explaining a process of forming electrodes of different shapes.

[0057] Figure 12 is a plan view of a deformed electrode sheet, and is a drawing for explaining the electrode formation process.

[0058]

[0059] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail, so that those skilled in the art can easily implement the present invention. When describing the operating principles of the embodiments of the present invention in detail, detailed descriptions of known functions or components will be omitted if they are deemed to unnecessarily obscure the gist of the present invention.

[0060] Parts with similar functions and actions are designated by the same drawing reference numerals throughout the drawings. Throughout the specification, when a part is said to be connected to another part, this includes not only direct connections but also indirect connections with other elements intervening. Furthermore, inclusion of a component does not exclude other components unless otherwise specifically stated, but rather implies the inclusion of additional components.

[0061] The description that concretizes or adds to the components may be applied to all inventions unless there is a special limitation, and is not limited to the description of a specific invention.

[0062] Throughout the description and claims of the invention herein, the singular includes the plural unless otherwise stated.

[0063] Throughout the description and claims of the present invention, the term "or" includes "and" unless otherwise stated. Therefore, "comprising A or B" means all three cases of including A, including B, or including A and B.

[0064] The metal foil in this specification is configured in a sheet form and is an object to which a first coating material and a second coating material are applied.

[0065] Additionally, the electrode sheet is defined as the period from after at least one of the first coating material and the second coating material is coated on the metal foil until before slitting.

[0066] In addition, the electrode mixture is used as a concept including an electrode slurry that includes a positive electrode active material or a negative electrode active material, a conductive material, a binder, a solvent, and an additive, and is in a state before the electrode mixture is dried.

[0067]

[0068] The present invention is described in detail with examples according to the drawings.

[0069] FIG. 1 is a perspective view of an electrode sheet manufacturing device according to a first embodiment of the present invention.

[0070] As illustrated in FIG. 1, an electrode sheet manufacturing device according to a first embodiment includes an unwinder (100) for taking out a metal foil (110), a rewinder (200) for winding the metal foil (110), a first coating member (300) for applying a first coating material (330) to a predetermined area of ​​the metal foil (110) taken out from the unwinder (100), a second coating member (400) for applying a second coating material (430) including an electrode active material, and a drying member (500) for volatilizing the first coating material (330).

[0071] To explain in detail, the unwinder (100) and the rewinder (200) are configured to continuously or intermittently transport the rolled metal foil (110) in one direction.

[0072] The first coating member (300) is configured to include one 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 length 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).

[0073] 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.

[0074] And 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.

[0075] The second coating member (400) positioned between the rewinder (200) and the first coating member (300) is configured to include two second nozzles (410) and a second coating material supply unit (420) for supplying a second coating material (430) to the second nozzles (410).

[0076] Here, in order to minimize the overlapping of the first coating material (330) and the second coating material (430) with each other and to enable the second coating material (430) to be continuously coated along the longitudinal direction (x) of the metal foil (110), it is preferable that the second nozzle (410) be positioned so as not to overlap with the first nozzle (310) with respect to the longitudinal direction (x).

[0077] The second coating material (430) may be an electrode mixture including an electrode active material, a binder, a conductive material, an additive, and a solvent, which may include a hydrophilic material.

[0078] For example, a polar solvent may be used as the hydrophilic solvent constituting the second coating material (430), and a representative hydrophilic solvent may be 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-styrene sulfonate, sodium vinyl sulfonate, sodium allyl sulfonate, sodium 2-methylallyl sulfonate, sodium ethyl methacrylate sulfonate, (meth)acrylamide, N-methylolacrylamide, N,N-dimethylacrylamide, and 2-acrylamide-2-methylpropane sulfonic acid.

[0079] The above electrode active material may include a conventional positive electrode active material and negative electrode active material for a lithium secondary battery, and its type is not limited.

[0080] Meanwhile, the first nozzle (310) and the second nozzle (410) may be slot dies capable of extruding and coating the first coating material (330) and the second coating material (430) supplied in the form of electrode slurry onto one side of the metal foil (110).

[0081] In this way, since the first coating material (330) includes a hydrophobic material while the second coating material (430) includes a hydrophilic material, even if the second coating material (430) is partially added 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) is applied, so that the second coating material (430) is coated only on the remaining area excluding the area where the first coating material (330) is applied.

[0082] The drying member (500) positioned between the second coating member (400) and the rewinder (200) is configured to evaporate the first coating material (330) and dry the second coating material (430).

[0083] Specifically, the metal foil (110) to which the first coating material (330) and the second coating material (430) are added is dried in the process of passing through the drying member (500). The drying member (500) may be configured in the form of a chamber inside 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.

[0084] In this way, in the present invention, since the drying process of the first coating material (330) and the second coating material (430) is carried out simultaneously, the manufacturing process is simpler and the manufacturing cost can be reduced compared to when the drying is carried out in separate processes.

[0085] As described above, an electrode sheet is formed on a metal foil (110) that has passed through a drying member (500), in which a non-coating portion from which the first coating material (330) has been removed and a maintenance portion coated with the second coating material (430) are formed.

[0086] Although not shown in FIG. 1, a support member (not shown) for supporting the metal foil (110) may be further arranged under the metal foil (110), and a first nozzle and a second nozzle may additionally be arranged on the lower surface of the metal foil (110).

[0087]

[0088] Fig. 2 is a perspective view of an electrode sheet manufacturing device according to a second embodiment of the present invention. Referring to Fig. 2, the electrode sheet manufacturing device according to the second embodiment is identical to the first embodiment except for the positions and number of the first nozzle (310) and the second nozzle (410).

[0089] To explain in detail, the first nozzle (310) for discharging the first coating material (330) is composed of two and is positioned at each end of the width direction (y) of the metal foil (110), while the second nozzle (410) for discharging the second coating material (430) is composed of one.

[0090] Of course, in order to minimize the 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 each other with respect to the longitudinal direction (x).

[0091]

[0092] Fig. 3 is a perspective view of an electrode sheet manufacturing device according to a third embodiment of the present invention, and Fig. 4 is a cross-sectional view taken along lines A-A', B-B', CC', and D-D' of Fig. 3, respectively. Referring to Fig. 3, the electrode sheet manufacturing device according to the third embodiment is identical to the first embodiment except for the positions and number of the first nozzle (310) and the second nozzle (410).

[0093] To explain in detail, the first nozzle (310) for discharging the first coating material (330) is composed of four and is positioned so as to be spaced apart at a certain distance between the ends in the width direction (y) of the metal foil (110), while the second nozzle (410) for discharging the second coating material (430) is composed of three along the width direction (y) of the metal foil (110).

[0094] Of course, in order to minimize the 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 each other with respect to the longitudinal direction (x).

[0095] Meanwhile, in FIG. 4, (a) is a vertical cross-sectional view taken along line A-A' of FIG. 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' of FIG. 3 in a state where the metal foil (110) passes through the first coating member (300) and is coated with the first coating material (330), (c) is a vertical cross-sectional view taken along line C-C' of FIG. 3 in a state where the second coating material (430) is also coated between the first coating materials (330) through the second coating member (400), and (d) is a cross-sectional view taken along line D-D' of FIG. 3 in a state where the first coating material (330) is removed through the drying member (500).

[0096] Since the first coating material (330) is added to the metal foil (110) to prevent the second coating material (430) from flowing down, it is preferable that the discharge amount be adjusted so that the thickness (D1) of the first coating material is less than or equal to the thickness (D2) of the second coating material (430).

[0097] Of course, since the first coating material (330) contains a volatile substance and can be removed by volatilization from 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.

[0098] Since the second coating material (430) is applied between the first coating materials (330), the first coating material (330) can act as a barrier that prevents the second coating material (430) from flowing down, so that not only is a sliding portion formed in an inclined shape on the outer periphery of the second coating material (430) not formed, but the second coating material (430) can maintain a constant thickness over the entire area.

[0099]

[0100] Figure 5 is a perspective view of an electrode sheet manufacturing device according to a fourth embodiment of the present invention.

[0101] Referring to FIG. 5, the electrode sheet manufacturing device according to the fourth embodiment is substantially similar to the second embodiment, except that the external appearance is different.

[0102] To explain in detail, in the second embodiment, the first coating material (330) and the second coating material (430) are supplied from the side, whereas in the fourth embodiment, the first coating material (330) and the second coating material (430) are supplied from the top.

[0103]

[0104] Fig. 6 is a perspective view of an electrode sheet manufacturing device according to a fifth embodiment of the present invention. Referring to Fig. 6, the electrode sheet manufacturing device according to the fifth embodiment is substantially similar to the third embodiment, with only a difference in appearance.

[0105] To explain in detail, in the third embodiment, the first coating material (330) and the second coating material (430) are supplied from the side, whereas in the fifth embodiment, the first coating material (330) and the second coating material (430) are supplied from the top.

[0106]

[0107] The following describes a method for manufacturing an electrode sheet using the aforementioned electrode sheet manufacturing device. FIG. 7 is a flow chart 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 device according to the first embodiment, which is a drawing for explaining the electrode formation process.

[0108] Referring to FIG. 7, the method for manufacturing an electrode sheet according to the present invention comprises a first step of supplying a metal foil, a second step of coating a first coating material including a hydrophobic material on the metal foil, a third step of coating a second coating material including an electrode active material on the metal foil, and a fourth step of drying the metal foil coated with the first coating material and the second coating material.

[0109] As described above, the first coating material (330) and the second coating material (430) are continuously applied 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) is volatilized during the drying process.

[0110] Accordingly, as illustrated in FIG. 8, the electrode sheet (1000) has an uncoated portion in the center of the width direction where the first coating material was applied, and the metal foil (110) is exposed, while a coated portion is formed on both sides of the uncoated portion where the second coating material (430) is applied.

[0111] When manufacturing an electrode using the electrode sheet (1000) of the shape described above, the electrode sheet (1000) is notched along the width-direction notching line of the electrode sheet (1000).

[0112] That is, by slitting along the width direction of the electrode sheet (1000) and notching the central portion where the metal foil (110) is exposed and the coating portion where the second coating material is applied along a thick dotted line, a plurality of electrodes (1100) having electrode tabs (1110) formed can be obtained.

[0113]

[0114] Fig. 9 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to a second embodiment, and is a drawing for explaining the electrode formation process. Referring to Fig. 9, when using an electrode sheet manufacturing device according to the second embodiment, the electrode sheet (1000) has an uncoated portion on both width-wise edges where the first coating material was applied, and a metal foil (110) is exposed, while a coated portion is formed in the center between the uncoated portions, where the second coating material (430) is applied.

[0115] When manufacturing an electrode using an electrode sheet (1000) of the shape described above, a plurality of electrodes (1100) having electrode tabs (1110) formed can be obtained by slitting along the length direction of the electrode sheet (1000) and notching the uncoated portion and the coated portion on both sides where the metal foil (110) is exposed along a thick dashed line.

[0116]

[0117] Fig. 10 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to a third embodiment, and is a drawing for explaining the electrode formation process. Referring to Fig. 10, when using an electrode sheet manufacturing device according to a third embodiment, an electrode sheet (1000) has a total of four regions including both width-wise edges where a first coating material was applied, as uncoated portions, in which a metal foil (110) is exposed, while a total of three regions in the center between the uncoated portions are formed as coated portions where a second coating material (430) is applied.

[0118] When manufacturing an electrode using an electrode sheet (1000) of the aforementioned shape, a plurality of electrodes (1100) having electrode tabs (1110) formed can be obtained by slitting along the longitudinal direction of the electrode sheet (1000) and notching the uncoated portions and coated portions where the metal foil (110) is exposed along a thick dashed line.

[0119] The electrode sheet (1000) of Fig. 10 is configured so that the sizes of the notching lines indicated by the thick dashed lines are different, so that two types of electrodes (1100) of different sizes can be manufactured.

[0120]

[0121] Fig. 11 is a plan view of an electrode sheet manufactured using an electrode sheet manufacturing device according to a third embodiment, and is a drawing for explaining a process of forming electrodes of different shapes. Referring to Fig. 11, when using an electrode sheet manufacturing device according to a third embodiment, an electrode sheet (1000) has a total of four regions including both edges in the width direction where a first coating material was applied, as uncoated portions in which a metal foil (110) is exposed, while a total of three regions in the center between the uncoated portions form coated portions where a second coating material (430) is applied.

[0122] When manufacturing an electrode using an electrode sheet (1000) of the aforementioned shape, a plurality of electrodes (1100) having electrode tabs (1110) formed can be obtained by slitting along the longitudinal direction of the electrode sheet (1000) and notching the uncoated portions and coated portions where the metal foil (110) is exposed along a thick dashed line.

[0123]

[0124] Fig. 12 is a plan view of a modified electrode sheet, and is a drawing for explaining the electrode formation process. Referring to Fig. 12, the electrode sheet (1000) may be manufactured using an electrode sheet manufacturing device having three first nozzles and three second nozzles alternately provided. The electrode sheet (1000) has three areas where the first coating material sprayed from the first nozzle was applied, and the metal foil (110) is exposed as an uncoated portion, while the remaining three areas excluding the uncoated portion form a coated portion where the second coating material (430) is applied.

[0125] When manufacturing an electrode using an electrode sheet (1000) of the aforementioned shape, a plurality of electrodes (1100) having electrode tabs (1110) formed can be obtained by slitting along the longitudinal direction of the electrode sheet (1000) and notching the uncoated portions and coated portions where the metal foil (110) is exposed along a thick dashed line.

[0126]

[0127] Electrodes manufactured through this process do not form a sliding part in the coating portion coated with the electrode active material, and when laminated with a separator, the phenomenon of the electrode and separator lifting does not occur, so problems such as increased resistance, electrolyte depletion, and lithium precipitation, which were previously encountered, can be minimized.

[0128]

[0129] Anyone with ordinary knowledge in the field to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

[0130]

[0131] (Explanation of symbols)

[0132] 100: Unwinder

[0133] 110: Metal foil

[0134] 200: Rewinder

[0135] 300: First coating member

[0136] 310: Nozzle 1

[0137] 320: First coating material supply unit

[0138] 330: First coating material

[0139] 400: Second coating member

[0140] 410: Second nozzle

[0141] 420: Second coating material supply unit

[0142] 430: Second coating material

[0143] 500: Dry member

[0144] 1000: Electrode sheet

[0145] 1100: Electrode

[0146] 1110: Electrode tab

[0147] D1: Thickness of the first coating material

[0148] D2: Thickness of the second coating material

Claims

1. Rewinder for winding metal foil; A first coating member positioned at the rear of the rewinder and applying a first coating material to a predetermined area of ​​the metal foil; A second coating member positioned between the above rewinder and the first coating member, and applying a second coating material including an electrode active material; An electrode sheet manufacturing device, characterized in that the applied first coating material and the applied second coating material do not overlap.

2. In paragraph 1, An electrode sheet manufacturing device, characterized in that the first coating material includes a hydrophobic material.

3. In paragraph 2, An electrode sheet manufacturing device, characterized in that the first coating material contains a volatile substance.

4. In paragraph 3, An electrode sheet manufacturing device characterized in that it further includes a drying member for volatilizing the first coating material between the rewinder and the second coating member.

5. In paragraph 1, An electrode sheet manufacturing device, characterized in that the first coating member and the second coating member are slot dies.

6. In paragraph 1, The first coating member comprises at least one first nozzle, and a first coating material supply unit for supplying the first coating material to the first nozzle, An electrode sheet manufacturing device, characterized in that the second coating member includes at least one second nozzle, and a second coating material supply unit for supplying the second coating material to the second nozzle.

7. In paragraph 6, An electrode sheet manufacturing device, characterized in that 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 based on the longitudinal direction (x) of the metal foil.

8. In paragraph 6, An electrode sheet manufacturing device, characterized in that the first nozzle is one and the second nozzle is two, and the first nozzle and the second nozzle are positioned so as not to overlap with respect to the longitudinal direction (x) of the metal foil.

9. In paragraph 6, An electrode sheet manufacturing device, characterized in that the first nozzle and the second nozzle are a plurality of nozzles spaced apart at a set interval along the width direction (y) of the metal foil, but the first nozzle and the second nozzle are positioned so as not to overlap when based on the length direction (x) of the metal foil.

10. In paragraph 1, An electrode sheet manufacturing device, characterized in that the second coating material includes a hydrophilic material.

11. First step of supplying metal foil; A second step of coating a first coating material containing a hydrophobic material on the metal foil; and A third step of coating a second coating material including an electrode active material on the metal foil; including, A method for manufacturing an electrode sheet, characterized in that the first coating material and the second coating material are continuously applied along the longitudinal direction (x) of the metal foil.

12. In paragraph 11, A method for manufacturing an electrode sheet, characterized in that the first coating material and the second coating material do not overlap.

13. In paragraph 11, A method for manufacturing an electrode sheet, characterized in that it further includes a fourth step of drying the metal foil coated with the first coating material and the second coating material after the third step.

14. In paragraph 12, A method for manufacturing an electrode sheet, characterized in that in the second step, the first coating material is a plurality of pieces spaced apart along the width direction (y) of the metal foil.

15. In paragraph 12, A method for manufacturing an electrode sheet, characterized in that the second coating material includes a hydrophilic material.

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