Electrode sheet manufacturing apparatus

Abstract

The present invention relates to an electrode sheet manufacturing apparatus, comprising: an electrode current collector unit comprising an electrode current collector sheet supply roll for supplying an electrode current collector sheet and an electrode current collector sheet winding roll for rewinding the electrode current collector sheet; a coating unit for coating electrode slurry onto the electrode current collector sheet; and a guide unit comprising strip-shaped guide members for preventing the electrode slurry from flowing down, wherein the guide members are in contact with, but not attached to, the electrode current collector sheet.

Description

Electrode sheet manufacturing device

[0001] This application claims the benefit of priority based on Korean Patent Application No. 2024-0148865 filed on October 28, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0002] The present invention relates to an electrode sheet manufacturing apparatus. Specifically, it relates to an electrode sheet manufacturing apparatus for forming an electrode layer of uniform thickness by preventing an electrode slurry coated on an electrode current collector sheet from flowing down.

[0003]

[0004] Due to the need for eco-friendly alternative energy driven by rapidly worsening climate change and carbon emission regulations, research and development on lithium-ion batteries with high energy density and high power output characteristics is actively underway.

[0005] A lithium secondary battery can be manufactured by a process of manufacturing an electrode sheet by forming an electrode composite layer on at least one surface of an electrode current collector sheet, forming a unit electrode by slitting and notching the electrode sheet, and manufacturing an electrode assembly by stacking the unit electrode together with a separator.

[0006] The above electrode assembly can increase the adhesion between the electrode and the separator by undergoing a lamination process in which a separator is laminated between the anode and the cathode and then heated and pressurized.

[0007] However, in order to form the electrode composite layer, the electrode slurry is coated onto an electrode current collector sheet and then dried. Before drying, the electrode slurry may flow down from both ends of the electrode composite layer, causing a portion where the thickness of the electrode composite layer becomes thin. The portion where the thickness of the electrode composite layer becomes thin in this way is called a sliding portion.

[0008] When the above sliding part is formed, that part cannot adhere to the separator and becomes loose, which not only reduces charge / discharge efficiency but can also cause lithium ion precipitation. Since the accumulation of lithium ion precipitation can reduce the battery capacity, various attempts are being made to prevent the formation of the sliding part.

[0009] Patent Document 1 manufactures an electrode by a process of attaching a masking tape to the surface of a current collector, laminating an active material, and then removing the masking tape to form a non-laminated portion of the active material.

[0010] However, the electrode manufacturing method of Patent Document 1 includes the process of laminating an active material onto a masking tape and removing the masking tape on which the active material is laminated, which has the disadvantage of unnecessarily wasting the active material.

[0011] Patent Document 2 discloses a method for manufacturing an electrode by 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, and forming an electrode composite layer by coating the electrode slurry within the area surrounded by the dam line coating layer.

[0012] The electrode manufactured in Patent Document 2 is in the form of a dam line coating layer that surrounds the entire outer periphery of the electrode composite layer, and since the area of ​​the electrode composite layer is reduced by the area where the dam line coating layer is formed, the capacity of the battery is inevitably reduced.

[0013] In addition, since Patent Document 2 is a method for manufacturing a single electrode, there is a problem in that it is difficult to apply it to a process for manufacturing an electrode sheet.

[0014] Accordingly, a technology is required to form an electrode composite layer with a uniform thickness by preventing sliding portions from forming in the electrode composite layer during the step of forming the electrode composite layer on the electrode current collector sheet to manufacture an electrode sheet.

[0015] (Prior Art Literature)

[0016] (Patent Document 1) Korean Published Patent Application No. 2023-0008975 (January 17, 2023)

[0017] (Patent Document 2) Korean Published Patent Application No. 2022-0124918 (September 14, 2022)

[0018]

[0019] The present invention aims to solve the above-mentioned problem by providing an electrode sheet manufacturing apparatus capable of uniformly forming the thickness of the electrode composite layer by applying a guide part to prevent the electrode slurry from flowing down during the process of manufacturing the electrode sheet.

[0020]

[0021] An electrode sheet manufacturing apparatus according to the present invention for achieving such objectives comprises an electrode current collector section including an electrode current collector sheet supply roll for supplying an electrode current collector sheet and an electrode current collector sheet winding roll for rewinding the electrode current collector sheet, a coating section for coating an electrode slurry on the electrode current collector sheet, and a guide section including a strip-shaped guide member for preventing the electrode slurry from flowing down, wherein the guide member may be in a form that contacts the electrode current collector sheet but is not attached.

[0022] In the electrode sheet manufacturing apparatus according to the present invention, the guide portion adds the guide members to both ends parallel to the transport direction of the electrode current collector sheet, and the coating portion can coat the electrode slurry on the electrode current collector sheet to which the guide members are added.

[0023] In the electrode sheet manufacturing apparatus according to the present invention, the coating portion can coat an electrode slurry on the remaining portion of the surface of the electrode current collector sheet where the guide member is not located.

[0024] In the electrode sheet manufacturing apparatus according to the present invention, a drying unit for drying the electrode slurry may be further included at the front end of the electrode current collector sheet winding roll.

[0025] In the electrode sheet manufacturing apparatus according to the present invention, the thickness of the guide member may be configured to be thicker than the coating thickness of the electrode slurry.

[0026] In the electrode sheet manufacturing apparatus according to the present invention, the transfer speed of the guide member can be configured to be the same as the transfer speed of the electrode current collector sheet.

[0027] In the electrode sheet manufacturing apparatus according to the present invention, a plurality of supports are further included to prevent the guide member from detaching, and the plurality of supports may be positioned to support a second outer surface opposite to the first outer surface facing the electrode slurry among the outer surfaces of the guide member.

[0028] In the electrode sheet manufacturing apparatus according to the present invention, a roller may be mounted on the portion of the support that contacts the guide member.

[0029] In the electrode sheet manufacturing apparatus according to the present invention, an adjustment unit for adjusting the length of the support member may be further included.

[0030] In the electrode sheet manufacturing apparatus according to the present invention, the guide member may further include a plurality of guide rolls that guide the conveying direction of the guide member.

[0031] The electrode sheet manufacturing apparatus according to the present invention may further include a cleaning unit for cleaning the guide member.

[0032] In the electrode sheet manufacturing apparatus according to the present invention, the guide member is formed as a wound type wound on a roll that rotates by a rotation axis, and the guide portion may include a guide member supply roll that supplies the guide member to both ends of the electrode current collector sheet, and a guide member winding roll that rewinds the guide member after the coating and drying of the electrode slurry are completed.

[0033] In the electrode sheet manufacturing apparatus according to the present invention, the guide member is configured such that a plurality of guideline members are connected in a closed circuit form through a connecting link, and the guide member can be rotated by a transfer roller while attached to both ends of the electrode current collector sheet.

[0034] In the electrode sheet manufacturing apparatus according to the present invention, the length of the guide member can be adjusted through the connecting link.

[0035] The present invention can also be provided in a form that combines various means for solving the above problem.

[0036]

[0037] The electrode sheet manufacturing apparatus according to the present invention can prevent the electrode slurry coated on the electrode current collector from flowing down, thereby forming an electrode composite layer with a uniform thickness.

[0038] In addition, since the guide member is attached to the electrode current collector sheet but does not come into contact with it, the guide member can be easily removed from the electrode current collector sheet.

[0039] In addition, even if the guide member becomes contaminated with impurities such as electrode slurry, it can be reused after washing.

[0040]

[0041] FIG. 1 is a schematic diagram of an electrode sheet manufacturing apparatus according to the first embodiment of the present invention.

[0042] FIG. 2 is an enlarged view of part A of FIG. 1, a perspective view showing electrode slurry being coated on an electrode current collector sheet with an added guide member.

[0043] Figure 3 is a vertical cross-sectional view of the electrode sheet with a support added.

[0044] Figure 4 is a plan view of the electrode sheet with a support added thereto.

[0045] FIG. 5 is a schematic diagram of an electrode sheet manufacturing apparatus according to the second embodiment of the present invention.

[0046]

[0047] Embodiments that enable a person skilled in the art to easily practice the present invention are described in detail below with reference to the attached drawings. In describing the operating principles of the embodiments of the present invention in detail, specific descriptions of related known functions or configurations are omitted if it is determined that such detailed descriptions may unnecessarily obscure the essence of the present invention.

[0048] The same reference numerals are used for parts having similar functions and operations throughout the drawings. Throughout the specification, when a part is described as being connected to another part, this includes not only cases where they are directly connected but also cases where they are indirectly connected with other elements in between. Furthermore, the inclusion of a certain component means that, unless specifically stated otherwise, it does not exclude other components but rather implies that additional components may be included.

[0049] Descriptions that specify or add components may be applied to all inventions unless specifically limited and are not limited to descriptions of specific inventions.

[0050] Throughout the description of the invention and claims of this application, anything indicated in the singular includes cases where it is plural unless otherwise noted.

[0051] Throughout the description of the invention and the claims of the present invention, "or" includes "and" unless otherwise noted. Therefore, "comprising A or B" means all three of the above cases: including A, including B, or including both A and B.

[0052] The present invention is described in detail with reference to the drawings and embodiments.

[0053] FIG. 1 is a schematic diagram of an electrode sheet manufacturing apparatus according to the first embodiment of the present invention, and FIG. 2 is an enlarged view of part A of FIG. 1 showing an electrode slurry being coated on an electrode current collector sheet to which a guide member is added.

[0054] Referring to FIGS. 1 and 2, the electrode sheet manufacturing apparatus according to the present invention comprises an electrode current collector section (100) including an electrode current collector sheet supply roll (110) for supplying an electrode current collector sheet (10) and an electrode current collector sheet winding roll (120) for rewinding the electrode current collector sheet (10), a coating section (200) for coating an electrode slurry (20) on the electrode current collector sheet (10), and a guide section (300) including a strip-shaped guide member (310) for preventing the electrode slurry (20) from flowing down.

[0055] In the present invention, the guide member (310) is configured to be in contact with the electrode current collector sheet (10) but not attached, and the guide member (310) is positioned to be in close contact with the upper surface of the electrode current collector sheet (10).

[0056] In the first embodiment of the electrode sheet manufacturing apparatus according to the present invention, the guide member (310) is formed as a wound type wound on a roll that rotates by a rotation axis, and the guide section (300) includes a guide member supply roll (320) that supplies the guide member (310) to both ends of the electrode current collector sheet (10), and a guide member winding roll (330) that rewinds the guide member (310) after the coating and drying of the electrode slurry (20) are completed.

[0057] The guide member supply roll (320) is located at the front end of the electrode current collector sheet supply roll (110) and the guide member winding roll (330) is located at the rear end of the electrode current collector sheet winding roll (120), and the guide section (300) may further include a plurality of guide rolls (340) that guide the transport direction of the guide member (310).

[0058] A guide roll (340) is positioned between the guide member supply roll (320) and the electrode current collector sheet supply roll (110) so that the transport direction of the guide member (310) can be changed by 90 degrees, and a guide roll (340) is positioned between the electrode current collector sheet winding roll (120) and the guide member winding roll (330) so that the transport direction of the guide member (310) can be changed by 90 degrees. In this way, a plurality of guide rolls (340) are arranged between the guide member supply roll (320) and the guide member winding roll (330) to change the transport path of the guide member (310), so that the guide member (310) can move in a taut state. Alternatively, the number and position of the guide rolls (340) are not limited to the form shown in FIG. 1, and more guide rolls (340) may be arranged so that the transport path of the guide member (310) is configured in a zigzag form, and the change in the transport direction of the guide member (310) is not limited to 90 degrees.

[0059] The guide section (300) adds guide members (310) to each of the two ends parallel to the transport direction (x) of the electrode current collector sheet (10), and the coating section (200) coats the electrode slurry (20) on the electrode current collector sheet (10) to which the guide members (310) are added. Specifically, the coating section (200) coats the electrode slurry (20) on the remaining portion of the surface of the electrode current collector sheet (10) where the guide members (310) are not located. That is, the electrode slurry (20) is coated within the space between the guide members (310) so as not to overlap with the guide members (310). The electrode slurry (20) may flow down and spread due to its own flowability before drying, but by adding the guide members (310), the electrode slurry (20) can be prevented from flowing down, thereby minimizing the formation of sliding portions and preventing thickness variations in the electrode composite layer.

[0060] Additionally, referring to FIG. 2, by configuring the thickness (D1) of the guide member to be equal to or thicker than the coating thickness (D2) of the electrode slurry, it is possible to prevent the electrode slurry from flowing down and creating a sliding portion before drying. Additionally, it is possible to prevent the electrode slurry from flowing down beyond the guide member (310).

[0061] Specifically, the coating thickness (D2) of the electrode slurry is formed with a uniform thickness in a single model, but can be formed with a required thickness in the range of 50 μm to 500 μm for each model, and the thickness (D1) of the guide member can be the same as the coating thickness (D2) of the electrode slurry, or can be formed to be at least 1 μm thicker than the coating thickness (D2) of the electrode slurry.

[0062] The present invention may further include a drying unit (400) for drying the electrode slurry at the front end of the electrode current collector sheet winding roll (120) so as to rapidly dry the electrode slurry and wind the dried electrode sheet onto the electrode current collector sheet winding roll.

[0063] Meanwhile, the conveying speed of the guide member (310) can be determined by the rotational speed of the guide member supply roll (320) and the guide member winding roll (330). If there is a difference between the conveying speed of the guide member (310) and the conveying speed of the electrode current collector sheet, a shear force is generated due to the frictional force between the two. Due to this shear force, the electrode slurry may move in the opposite direction to the conveying direction of the electrode current collector sheet, and an unnecessary slope may occur in the electrode slurry coating, causing a variation in the coating thickness. Such a difference in coating thickness and a difference in the amount of electrode active material loaded may affect the quality of the electrode.

[0064] Therefore, it is desirable that the transfer speed of the guide member be configured to be the same as the transfer speed of the electrode current collector sheet.

[0065] FIG. 3 is a vertical cross-sectional view of an electrode sheet with a support added thereto, and FIG. 4 is a plan view of an electrode sheet with a support added thereto.

[0066] Referring to FIGS. 3 and 4, an electrode slurry (20) is coated on an electrode current collector sheet (10), and guide members (310) are positioned at both ends in the width direction (W) of the electrode current collector sheet (10).

[0067] On the outer side of the guide member (310), a plurality of supports (610) are arranged to contact the guide member (310) to prevent the guide member (310) from detaching. The plurality of supports (610) are positioned to support the second surface (312), which is the outer surface opposite to the first surface (311) facing the electrode slurry (20) among the outer surfaces of the guide member (310).

[0068] Since a plurality of supports (610) are arranged to come into contact with the guide member (310), friction may occur at the contact surface between the plurality of supports (610) and the guide member (310), which may affect the transport speed of the guide member (310). Accordingly, a roller (620) may be mounted on the part of the support (610) that comes into contact with the guide member (310).

[0069] The roller (620) is configured to rotate around a rotation axis (621) positioned perpendicular to the plane of the electrode current collector sheet (10), so that the rotation direction and rotation speed of the roller (621) can be configured to match the conveying direction and conveying speed of the guide member (310).

[0070] In addition, since a plurality of supports (610) are arranged along the transport path of the electrode current collector sheet (10), it may be necessary to adjust the width and height depending on the position where the plurality of supports (610) are arranged. Accordingly, the plurality of supports (610) can be adjusted in width direction (W) and height by further providing an adjustment part (630) for length adjustment.

[0071] For example, the adjustment part (630) may be positioned between two rods that overlap and adjust the length, and may be in a form that rotates clockwise or counterclockwise to be in an unlocked and locked state for length adjustment, or it may be in a form where a screw groove is formed inside the adjustment part (6300) and a screw with a screw thread corresponding to the screw groove is fixed to the support (610), and the length of the screw inserted into the adjustment part (630) is adjusted so that the overall length of the support (610) can be adjusted.

[0072] Alternatively, if the support is of an adjustable length, it can be applied without any particular restrictions on its form.

[0073] Meanwhile, the guide member (310) may be contaminated by the electrode slurry (20), and if it is used repeatedly, foreign substances may be transferred to other electrode slurries (20), causing electrode defects. Accordingly, a cleaning unit (500) for cleaning the guide member (310) may be further included. For example, in the case of the electrode sheet manufacturing device according to the first embodiment, as shown in FIG. 1, the cleaning unit (500) is provided between the rear end of the electrode current collector sheet winding roll (120) and the front end of the guide member winding roll (330), so that the guide member (310) can be cleaned before being wound onto the guide member winding roll (330).

[0074] FIG. 5 is a schematic diagram of an electrode sheet manufacturing apparatus according to the second embodiment of the present invention.

[0075] Referring to FIG. 5, the electrode sheet manufacturing apparatus according to the second embodiment of the present invention is configured such that a guide member (310) is configured such that a plurality of guides are connected in a closed circuit form through a connecting link (350), and the guide member (310) is configured to rotate by a transfer roller (340) while attached to both ends of the electrode current collector sheet (10).

[0076] Since the guide member (310) is connected in a closed-loop form, continuous transport can be achieved along a fixed transport path. Therefore, unlike in the first embodiment, the process of separating the guide member winding roll, on which the entire guide member is wound, and moving it to the guide member supply roll position is unnecessary.

[0077] However, in the electrode sheet manufacturing process, the length from the electrode current collector sheet supply roll (110) to the electrode current collector sheet winding roll (120) may change, and since it may be difficult to manage if the guide member is too long, the length of the guide member (310) can be adjusted by configuring a plurality of guides to be connected through a connecting link (350).

[0078] Since the closed circuit of the guide member rotates while maintaining a taut state, the guide member can be stably attached to the electrode current collector sheet even without the addition of a separate adhesive material.

[0079] In the electrode sheet manufacturing device according to the second embodiment, a cleaning section (500) can be placed in the conveying path of the guide member (310). In the second embodiment, since the guide member (310) moves continuously, the cleaning section (500) can be placed in the remaining part excluding the space between the electrode assembly sheet supply roll (110) and the electrode assembly sheet winding roll (120).

[0080] In addition, the description regarding the position where the coating part coats the electrode slurry, the drying part, and the plurality of supports (610) for preventing the guide member from detaching can be applied in the same way to the electrode sheet manufacturing device according to the second embodiment as described in the electrode sheet manufacturing device according to the first embodiment.

[0081]

[0082] A person skilled in the art to which the present invention pertains would be able to perform various applications and modifications within the scope of the present invention based on the above content.

[0083] (Explanation of symbols)

[0084] 10: Electrode current collector sheet

[0085] 20: Electrode slurry

[0086] 100: Electrode current collector part

[0087] 110: Electrode current collector sheet supply roll

[0088] 120: Electrode current collector sheet winding roll

[0089] 200: Coating section

[0090] 300: Guide Department

[0091] 310: Lack of guide

[0092] 311: Page 1

[0093] 312: Page 2

[0094] 320: Guide member supply roll

[0095] 330: Guideless winding roll

[0096] 340: Guide Roll

[0097] 350: Connection Link

[0098] 400: Drying section

[0099] 500: Washing section

[0100] 610: Support

[0101] 620: Roller

[0102] 621: Rotation axis

[0103] 630: Control section

Claims

1. An electrode current collector unit comprising an electrode current collector sheet supply roll for supplying an electrode current collector sheet and an electrode current collector sheet winding roll for rewinding the electrode current collector sheet; A coating unit for coating an electrode slurry on the electrode current collector sheet; and A guide section including a strip-shaped guide member for preventing the electrode slurry from flowing down; Includes, The above guide member is in a form that contacts the electrode current collector sheet but is not attached to it, forming an electrode sheet manufacturing device.

2. In Paragraph 1, The above guide section adds the guide members to both ends parallel to the transport direction of the electrode current collector sheet, and The above coating portion is an electrode sheet manufacturing apparatus that coats the electrode slurry onto an electrode current collector sheet to which the above guide member is attached.

3. In Paragraph 2, The above coating portion is an electrode sheet manufacturing apparatus that coats an electrode slurry on the remaining portion of the surface of the electrode current collector sheet where the guide member is not located.

4. In Paragraph 1, An electrode sheet manufacturing apparatus further comprising a drying section for drying the electrode slurry at the front end of the electrode current collector sheet winding roll.

5. In Paragraph 1, An electrode sheet manufacturing apparatus in which the thickness of the guide member is configured to be thicker than the coating thickness of the electrode slurry.

6. In Paragraph 1, An electrode sheet manufacturing apparatus in which the transfer speed of the above guide member is configured to be the same as the transfer speed of the above electrode current collector sheet.

7. In Paragraph 1, It further includes a plurality of supports to prevent the above guide member from detaching, and The electrode sheet manufacturing apparatus in which the plurality of supports are positioned to support a second outer surface opposite to the first outer surface facing the electrode slurry among the outer surfaces of the guide member.

8. In Paragraph 7, An electrode sheet manufacturing device having a roller mounted on the part of the support that contacts the guide member.

9. In Paragraph 7, An electrode sheet manufacturing device further comprising an adjustment part for adjusting the length of the above-mentioned support.

10. In Paragraph 1, The above guide section is an electrode sheet manufacturing apparatus further comprising a plurality of guide rolls that guide the conveying direction of the guide member.

11. In Paragraph 1, An electrode sheet manufacturing apparatus further comprising a cleaning unit for cleaning the above guide member.

12. In Paragraph 1, The above guide member is formed as a wound type wound on a roll that rotates by a rotation axis, and the guide member comprises a guide member supply roll that supplies the guide member to both ends of the electrode current collector sheet, and a guide member winding roll that rewinds the guide member after the coating and drying of the electrode slurry are completed.

13. In Paragraph 1, The above guide member is configured such that a plurality of guidelines are connected in a closed-loop form through connecting links, and An electrode sheet manufacturing device in which the above guide member is attached to both ends of the electrode current collector sheet and rotated by a transfer roller.

14. In Paragraph 13, An electrode sheet manufacturing device in which the length of the guide member is adjusted through the above-mentioned connecting link.

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