Curl reduction roller of electrode sheet, electrode assembly manufacturing device and electrode assembly manufacturing method

Abstract

The present invention provides an electrode assembly manufacturing device comprising: an unwinder (200) for unwinding an electrode sheet (50); an electrode sheet curl-reducing roller (100) which is in contact with the electrode sheet (50) and reduces curl which can form on one side of the electrode sheet (50) in the thickness direction; a winding core (300) for winding the electrode sheet (50), the end of which is fixed, by rotating; a transfer unit (400) for inserting the electrode sheet (50) into the winding core (300); and a cutter (500) cutting the electrode sheet (50) inserted into the winding core (300).

Description

Curl reduction roller for electrode sheet, electrode assembly manufacturing device and electrode assembly manufacturing method

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0029249, dated February 28, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a curl reduction roller for an electrode sheet, an electrode assembly manufacturing device, and an electrode assembly manufacturing method, wherein curls that can be formed in an electrode sheet are easily and effectively reduced at low cost with a simple configuration, the bending amount and the transport direction of the electrode sheet can be easily controlled, the tip (core portion) of the electrode sheet can be easily and stably inserted / injected into a core, the electrode sheet can not be twisted after being inserted / injected into a core, cutting defects do not occur, and reverse curls are reduced. The present invention relates to a curl reduction roller for an electrode sheet, an electrode assembly manufacturing device, and an electrode assembly manufacturing method, wherein curls that can be formed in an electrode sheet can be easily and effectively reduced at low cost with a simple configuration, the bending amount and the transport direction of the electrode sheet can be easily controlled, the tip (core portion) of the electrode sheet can be easily and stably inserted / injected into a core, and the electrode sheet can not be twisted after being inserted / injected into a core, and reverse curls are reduced.

[0003] As illustrated in FIG. 1, the electrode sheet (50) may include a current collector (52) and a composite layer (54). In addition, the electrode sheet (50) may include a holding portion (G1) on which the composite layer (54) is formed on the current collector (52) and a non-coated portion (G2) on which the composite layer (54) is not formed on the current collector (52). The electrode sheet (50) may include a plurality of unit electrode sheets (U) having a predetermined length. Each unit electrode sheet (U) may include a holding portion (G1) and a non-coated portion (G2) and may constitute an electrode assembly. The electrode sheet (50) may be cut at a predetermined point (C) so that the unit electrode sheet (U) may be separated from the neighboring unit electrode sheet (U). The electrode assembly manufacturing process may be performed in a state in which at least one end (tip) of the unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U).

[0004] Meanwhile, as illustrated in FIG. 2, the unit electrode sheet (U) may have a first section (S1) of a longitudinal end (tip) on one side of the electrode current collector (52) on which a composite layer (54) is applied and on the other side on which the composite layer (54) is not applied. When one end (tip) of the unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U), the one end (tip) of the unit electrode sheet (U) may be bent by the first section (S1) to one side in the thickness direction on which the composite layer (54) is not applied. That is, a curl may be formed in one side in the thickness direction at the end (tip) of the unit electrode sheet (U). This may be because a difference in elongation occurs between one side and the other side in the thickness direction of the unit electrode sheet (U) in the first section (S1).

[0005] Since the electrode assembly manufacturing process is performed in a state where at least one end (tip) of the unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U), in the case where the unit electrode sheet (U) has the first section (S1), the electrode assembly manufacturing process may have to be performed in a state where a curl is formed at the tip of the unit electrode sheet (U).

[0006] At this time, the electrode assembly manufacturing process may not be performed or a manufacturing defect may occur due to the curl of the tip of the unit electrode sheet (U). For example, in a winding process for manufacturing a jelly-roll-type electrode assembly by winding the unit electrode sheet (U) and the separator (70) together, the tip (core) of the unit electrode sheet (U) may i) not be inserted / injected into the winding core (300) due to the curl, and ii) even if it is inserted / injected into the winding core (300), the unit electrode sheet (U) may meander, resulting in a winding defect or a separation (cutting) defect at the rear end of the unit electrode sheet (U). Here, the winding core (300) may be a component that fixes and rotates the tip (core) of the unit electrode sheet (U) and the separator (70) inserted / injected inside to form a jelly-roll-type electrode assembly.

[0007] Therefore, a method for reducing curl at one end (tip) of a unit electrode sheet (U) is required. In particular, since curl may become more severe when the length of the first section (S1) increases, a method for reducing curl is urgently required.

[0008] A related prior art document is Korean Patent Publication No. 10-2023-0149762.

[0009] The present invention has been devised to solve the above-described problems, and its purpose is to provide a curl reduction roller for an electrode sheet, an electrode assembly manufacturing device, and an electrode assembly manufacturing method, which can easily and effectively reduce curls that can be formed on an electrode sheet with a simple configuration and at low cost.

[0010] The purpose of the present invention is to provide an electrode sheet curl reduction roller, an electrode assembly manufacturing device, and an electrode assembly manufacturing method, which can easily control the amount of electrode sheet bending and the direction of transport after electrode sheet bending.

[0011] The purpose of the present invention is to provide a curl reduction roller for an electrode sheet that is miniaturized and lightweight and allows for easy transport of the electrode sheet, an electrode assembly manufacturing device, and an electrode assembly manufacturing method.

[0012] The present invention aims to provide an electrode assembly manufacturing device and an electrode assembly manufacturing method in which the tip portion (core portion) of an electrode sheet can i) be easily and stably inserted / injected into a core, and ii) the electrode sheet does not meander and cutting defects do not occur after being inserted / injected into the core.

[0013] The purpose of the present invention is to provide an electrode assembly manufacturing device and an electrode assembly manufacturing method in which reverse curl is reduced so that the electrode sheet does not meander after being inserted / injected into the core and cutting defects do not occur.

[0014]

[0015] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0016] In order to solve the above-described problem, the present invention provides an electrode assembly manufacturing device (10) including a winding machine (200); a curl reduction roller (100) of an electrode sheet; a core (300); a conveying part (400); and a cutter (500).

[0017] The above-mentioned extractor (200) can extract the electrode sheet (50).

[0018] The curl reduction roller (100) of the above electrode sheet can reduce curls that may be formed on one side of the electrode sheet (50) in the thickness direction by coming into contact with the electrode sheet (50).

[0019] The above-mentioned winding core (300) can rotate to wind the electrode sheet (50) while the end of the electrode sheet (50) is fixed.

[0020] The above-mentioned transfer unit (400) can feed the electrode sheet (50) into the core (300).

[0021] The above cutter (500) can cut the electrode sheet (50) fed into the core (300).

[0022] The curl reduction roller (100) of the above electrode sheet may include a first roller (110) and a second roller (120) or the second roller (120) and a third roller (130).

[0023] The first roller (110) and the second roller (120) or the second roller (120) and the third roller (130) can sequentially come into contact with the electrode sheet (50) being transported in the longitudinal direction.

[0024] The first roller (110) and the second roller (120) or the second roller (120) and the third roller (130) can change the transport direction of the electrode sheet (50).

[0025] Each of the first roller (110) and the third roller (130) may contact the electrode sheet (50) along the outer circumference, but may contact the electrode sheet (50) so that the electrode sheet (50) is bent to one side in the thickness direction.

[0026] The second roller (120) may contact the electrode sheet (50) along the outer circumference, but may contact the electrode sheet (50) so that the electrode sheet (50) is bent to the other side in the thickness direction.

[0027] The second diameter (R2) of the second roller (120) may be greater than 0 and smaller than the first diameter (R1) of the first roller (110) and the third diameter (R3) of the third roller (130).

[0028] The curl reduction roller (100) of the electrode sheet may be arranged downstream of the winding machine (200) in the transport path of the electrode sheet (50), but upstream of the cutter (500).

[0029] The transport distance of the electrode sheet (50) from the above-mentioned extruder (200) to the curl reduction roller (100) of the electrode sheet may be smaller than the transport distance of the electrode sheet (50) from the curl reduction roller (100) of the electrode sheet to the cutter (500).

[0030] In one embodiment, the curl reduction roller (100) of the electrode sheet may be positioned adjacent to the winding machine (200).

[0031] In one embodiment, the curl reduction roller (100) of the electrode sheet may include the first roller (110), the second roller (120), and the third roller (130).

[0032] The first roller (110), second roller (120), and third roller (130) can sequentially come into contact with the electrode sheet (50) being transported in the longitudinal direction.

[0033] The first roller (110), second roller (120), and third roller (130) can change the transport direction of the electrode sheet (50).

[0034] In one embodiment, the second bending angle (E2) at which the electrode sheet (50) is bent while contacting the outer circumference of the second roller (120) may be greater than or equal to the first bending angle (E1) and the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumferences of the first roller (110) and the third roller (130), respectively.

[0035] In one embodiment, the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumference of the third roller (130) may be smaller than the first bending angle (E1) at which the electrode sheet (50) is bent while contacting the outer circumference of the first roller (110).

[0036] In one embodiment, the first roller (110), the second roller (120), and the third roller (130) can rotate around a virtual first axis (A1), a second axis (A2), and a third axis (A3) extending in the width direction, respectively.

[0037] In a first direction perpendicular to the virtual plane including the first axis (A1) and the third axis (A3), when the electrode sheet (50) comes into contact along the outer circumference of one side of the second roller (120), the second axis (A2) may be located on one side of the first axis (A1) and the third axis (A3).

[0038] In one embodiment, the second diameter (R2) may be greater than 0 and less than 3 / 5 of each of the first diameter (D1) and the third diameter (D3).

[0039] In one embodiment, the third diameter (D3) may be greater than or equal to the first diameter (D1).

[0040] In one embodiment, the fourth roller (140) and the first roller (110) and the second roller (120) may be included to sequentially contact the electrode sheet (50) being transported in the longitudinal direction and change the transport direction of the electrode sheet (50).

[0041] The fourth roller (140) may contact the electrode sheet (50) along the outer circumference, but may contact the electrode sheet (50) so that the electrode sheet (50) is bent to the other side in the thickness direction.

[0042] The fourth diameter (D4) of the fourth roller (140) may be greater than 0 and smaller than the first diameter (R1).

[0043] In order to solve the above-described problem, the present invention provides an electrode assembly manufacturing method (S900) including a fixing process (S910) of fixing the end of the electrode sheet (50) to the core (300); a winding process (S920) of winding the electrode sheet (50) by rotating the core (300); and a cutting process (S930) of cutting the first electrode sheet (50A).

[0044] When the electrode sheet (50) is transported in the above winding process (S920), a curl that may be formed on one side of the electrode sheet (50) in the thickness direction can be reduced by the curl reduction roller (100) of the electrode sheet.

[0045] According to embodiments of the present invention, an electrode assembly manufacturing device (10) may include: a winder (200) for winding an electrode sheet (50); a curl reduction roller (100) for reducing a curl that may be formed on one side of the electrode sheet (50) in the thickness direction by coming into contact with the electrode sheet (50); a winder (300) for winding the electrode sheet (50) by rotating while the end of the electrode sheet (50) is fixed; a conveying unit (400) for feeding the electrode sheet (50) into the winder (300); and a cutter (500) for cutting the electrode sheet (50) fed into the winder (300). The curl reduction roller (100) of the electrode sheet may include a first roller (110) and a second roller (120), or the second roller (120) and a third roller (130), which sequentially contact the electrode sheet (50) being transported in the longitudinal direction and change the transport direction of the electrode sheet (50). Each of the first roller (110) and the third roller (130) may contact the electrode sheet (50) along its outer circumference so that the electrode sheet (50) is bent to one side in the thickness direction. The second roller (120) may contact the electrode sheet (50) along its outer circumference so that the electrode sheet (50) is bent to the other side in the thickness direction. The second diameter (R2) of the second roller (120) may be greater than 0 and smaller than the first diameter (R1) of the first roller (110) and the third diameter (R3) of the third roller (130). The curl reduction roller (100) of the electrode sheet may be arranged downstream of the unwinder (200) in the transport path of the electrode sheet (50) and upstream of the cutter (500). The transport distance of the electrode sheet (50) from the unwinder (200) to the curl reduction roller (100) of the electrode sheet may be smaller than the transport distance of the electrode sheet (50) from the curl reduction roller (100) of the electrode sheet to the cutter (500).

[0046] Accordingly, the curl (Fig. 2) that may be formed at the tip of the first electrode sheet (50A) after being cut by the first cutter (500A) is reduced by the curl reduction roller (100) of the electrode sheet, so that the tip (core portion) of the first electrode sheet (50A) can i) be easily and stably inserted / injected into the core (300), and ii) the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0047] In addition, the transport distance from the curl reduction roller (100) of the electrode sheet to the first cutter (500A) or the core (300) may be increased. Accordingly, even if a reverse curl (a curl in the opposite direction to that in FIG. 2) in the thickness direction may be formed on the first electrode sheet (50A) by the curl reduction roller (100) of the electrode sheet, the reverse curl may be reduced by the tension applied to the first electrode sheet (50A) during the process of transporting the first electrode sheet (50A) to the first cutter (500A) or the core (300).

[0048] In addition, since the curvature of the second roller (120) is large, when the electrode sheet (50) is bent to the other side in the thickness direction by the second roller (120), the bending amount (bending angle) per unit length of the electrode sheet (50) can increase. Accordingly, the curl that can be formed in the electrode sheet (50) can be easily and effectively reduced at low cost with a simple configuration by the second roller (120).

[0049] In addition, since the curvature of the first and third rollers (110, 130) is small, when the electrode sheet (50) is bent in one direction in the thickness direction by the first roller (110) or the third roller (130), the bending amount per unit length of the electrode sheet (50) may be small. Accordingly, even if the electrode sheet (50) is bent by the first roller (110) or the third roller (130), a curl may not be formed in the electrode sheet (50) in one direction in the thickness direction or may be formed weakly.

[0050] In addition, since the first roller (110) is placed on the upstream side of the second roller (120) or the third roller (130) is placed on the downstream side, the bending amount of the electrode sheet (50) by the second roller (120) and the transport direction after bending of the electrode sheet (50) can be easily controlled.

[0051] According to embodiments of the present invention, the curl reduction roller (100) of the electrode sheet may be placed adjacent to the winding machine (200).

[0052] Accordingly, the transport distance from the curl reduction roller (100) of the electrode sheet to the first cutter (500A) or the core (300) can be lengthened. Therefore, even if a reverse curl (a curl in the opposite direction to FIG. 2) in the thickness direction may be formed on the first electrode sheet (50A) by the curl reduction roller (100) of the electrode sheet, the reverse curl can be reduced by the tension applied to the first electrode sheet (50A) during the process of transporting the first electrode sheet (50A) to the first cutter (500A) or the core (300). Therefore, the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0053] According to embodiments of the present invention, the curl reduction roller (100) of the electrode sheet may include the first roller (110), the second roller (120), and the third roller (130). The first roller (110), the second roller (120), and the third roller (130) may sequentially contact the electrode sheet (50) being transported in the longitudinal direction and change the transport direction of the electrode sheet (50).

[0054] Accordingly, since the first roller (110) and the third roller (130) are respectively arranged on the upstream and downstream sides of the second roller (120), the bending amount of the electrode sheet (50) by the second roller (120) and the transport direction after bending of the electrode sheet (50) can be easily controlled.

[0055] According to embodiments of the present invention, the second bending angle (E2) at which the electrode sheet (50) is bent while contacting the outer circumference of the second roller (120) may be greater than or equal to the first bending angle (E1) and the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumferences of the first roller (110) and the third roller (130), respectively.

[0056] Accordingly, since the bending amount (bending angle) of the electrode sheet (50) in the thickness direction on the other side by the second roller (120) increases, curls that may be formed on the electrode sheet (50) in the thickness direction on one side can be effectively reduced.

[0057] According to embodiments of the present invention, the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumference of the third roller (130) may be smaller than the first bending angle (E1) at which the electrode sheet (50) is bent while contacting the outer circumference of the first roller (110).

[0058] Accordingly, the degree to which the curl reduction effect by the second roller (120) is reduced / offset by the third roller (130) can be reduced.

[0059] According to embodiments of the present invention, the first roller (110), the second roller (120), and the third roller (130) can rotate around a virtual first axis (A1), a second axis (A2), and a third axis (A3) extending in the width direction, respectively. In a first direction perpendicular to an imaginary plane including the first axis (A1) and the third axis (A3), when the electrode sheet (50) comes into contact along the outer circumference of one side of the second roller (120), the second axis (A2) can be located on one side relative to the first axis (A1) and the third axis (A3).

[0060] Accordingly, since the bending amount (bending angle) of the electrode sheet (50) in the thickness direction on the other side by the second roller (120) can be increased, curls that may be formed on the electrode sheet (50) in the thickness direction on one side can be effectively reduced.

[0061] In addition, since the distance between the first and third rollers (110, 130) can be reduced, the curl reduction roller of the electrode sheet (50) can be made smaller and lighter. In addition, since the distance between the first and second rollers (110, 120) and the distance between the second and third rollers (120, 130) can be increased, the electrode sheet (50) can be easily transported.

[0062] According to embodiments of the present invention, the second diameter (R2) may be greater than 0 and less than a value obtained by multiplying each of the first diameter (D1) and the third diameter (D3) by 3 / 5.

[0063] Accordingly, since the diameter difference between the second roller (120) and the first and third rollers (110, 130) increases, curls that may be formed on the electrode sheet (50) can be effectively reduced by the second roller (120), and at the same time, even if the electrode sheet (50) is bent by the first roller (110) or the third roller (130), curls on the electrode sheet (50) may not be formed on one side in the thickness direction or may be formed weakly.

[0064] According to embodiments of the present invention, the third diameter (D3) may be greater than or equal to the first diameter (D1).

[0065] Accordingly, the degree to which the curl reduction effect by the second roller (120) is reduced / offset by the third roller (130) can be reduced.

[0066] According to embodiments of the present invention, the fourth roller (140) may be included, which sequentially contacts the electrode sheet (50) being transported in the longitudinal direction and changes the transport direction of the electrode sheet (50), and the first roller (110) and the second roller (120). The fourth roller (140) may contact the electrode sheet (50) along the outer circumference, and may contact the electrode sheet (50) so that the electrode sheet (50) is bent to the other side in the thickness direction. The fourth diameter (D4) of the fourth roller (140) may be greater than 0 and smaller than the first diameter (R1).

[0067] Accordingly, since the curvature of the fourth and second rollers (140, 120) is large, when the electrode sheet (50) is bent in the other direction in the thickness direction by the fourth and second rollers (140, 120), the bending amount (bending angle) per unit length of the electrode sheet (50) can increase. Accordingly, the curl that can be formed in the electrode sheet (50) can be easily and effectively reduced at low cost with a simple configuration by the fourth and second rollers (140, 120).

[0068] In addition, since the curvature of the first roller (110) is small, when the electrode sheet (50) is bent to one side in the thickness direction by the first roller (110), the bending amount per unit length of the electrode sheet (50) may be small. Accordingly, even if the electrode sheet (50) is bent by the first roller (110), a curl may not be formed on the electrode sheet (50) to one side in the thickness direction or may be formed weakly.

[0069] In addition, since the first roller (110) is placed on the downstream side of the fourth roller (140) and the upstream side of the second roller (120), the bending amount of the electrode sheet (50) by the fourth and second rollers (140, 120) can be easily controlled.

[0070] According to embodiments of the present invention, the electrode assembly manufacturing method (S900) may include a fixing step (S910) of fixing the end of the electrode sheet (50) to the winding core (300); a winding step (S920) of winding the electrode sheet (50) by rotating the winding core (300); and a cutting step (S930) of cutting the electrode sheet (50). When the electrode sheet (50) is conveyed in the winding step (S920), a curl that may be formed on one side of the electrode sheet (50) in the thickness direction can be reduced by the curl reduction roller (100) of the electrode sheet.

[0071] Accordingly, the curl (Fig. 2) that may be formed at the tip of the first electrode sheet (50A) after being cut by the first cutter (500A) is reduced by the curl reduction roller (100) of the electrode sheet, so that the tip (core portion) of the first electrode sheet (50A) can i) be easily and stably inserted / injected into the core (300), and ii) the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0072] In addition, when the first electrode sheet (50A) is transported in the fixing process (S910), a curl that may be formed on one side of the first electrode sheet (50A) in the thickness direction can be reduced by the curl reduction roller (100) of the electrode sheet.

[0073] In addition to the effects described above, specific effects of the present invention are described below while explaining specific details for carrying out the invention.

[0074] Figures 1 and 2 are side views schematically showing an electrode sheet according to one embodiment of the present invention.

[0075] Fig. 3 is a side view showing a curl reduction roller of an electrode sheet according to one embodiment of the present invention.

[0076] Figure 4 is a side view showing an electrode assembly manufacturing device according to one embodiment of the present invention.

[0077] Figure 5 is a flowchart of a method for manufacturing an electrode assembly according to one embodiment of the present invention.

[0078] [Explanation of symbols]

[0079] 10: Electrode assembly manufacturing device

[0080] 50: Electrode sheet

[0081] 50A: First electrode sheet 50B: Second electrode sheet

[0082] 52: Whole body 52: Composite layer

[0083] G1: Maintenance Department G2: Unmanned Department

[0084] C: designated point U: unit electrode sheet

[0085] S1: Section 1

[0086] 70: Membrane

[0087] 100: Curl reduction roller of electrode sheet

[0088] 110: 1st roller 120: 2nd roller

[0089] 130: 3rd roller 140: 4th roller

[0090] A1: Axis 1 A2: Axis 2

[0091] A3: Third axis A4: Fourth axis

[0092] D1: First diameter D2: Second diameter

[0093] D3: Third diameter D4: Fourth diameter

[0094] E1: First bending angle E2: Second bending angle

[0095] E3: Third bending angle E4: Fourth bending angle

[0096] 200: Volume 1 300: Volume 2

[0097] 400A: First conveyor 400B: Second conveyor

[0098] 500A: 1st cutter 500B: 2nd cutter

[0099] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0100] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0101] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0102] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0103] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0104] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0105]

[0106] Figures 1 and 2 are side views schematically illustrating an electrode sheet according to one embodiment of the present invention. Figure 3 is a side view illustrating a curl reduction roller of an electrode sheet according to one embodiment of the present invention. Figure 4 is a side view illustrating an electrode assembly manufacturing device according to one embodiment of the present invention. Figure 5 is a flowchart of a method for manufacturing an electrode assembly according to one embodiment of the present invention.

[0107]

[0108] [Electrode Sheet]

[0109] Referring to FIGS. 1 and 2, the electrode sheet (50) may include a current collector (52) and a composite layer (54) formed by applying a material including an active material to the current collector (52). In addition, the electrode sheet (50) may include a holding portion (G1) on which the composite layer (54) is formed on the current collector (52) and a non-forming portion (G2) on which the composite layer (54) is not formed on the current collector (52). The composite layer (54) may be formed on both sides or on one side of the current collector (52). The holding portion (G1) and the non-forming portion (G2) may be formed alternately in the longitudinal direction of the electrode sheet (50).

[0110] The electrode sheet (50) may include a plurality of unit electrode sheets (U) having a predetermined length. The plurality of unit electrode sheets (U) may be connected to each other in the longitudinal direction. Each unit electrode sheet (U) may include a holding portion (G1) and a non-holding portion (G2) and may constitute an electrode assembly.

[0111] When the electrode sheet (50) is cut at a predetermined point (C), the unit electrode sheet (U) can be separated from the neighboring unit electrode sheet (U). That is, in the first, second, and third unit electrode sheets (U) that are adjacent to each other in the length direction, when the point (C) between the first and second unit electrode sheets (U) is cut, one end (front end) of the second unit electrode sheet (U) can be separated from the first unit electrode sheet (U), and when the point (C) between the second and third unit electrode sheets (U) is cut, the other end (rear end) of the second unit electrode sheet (U) can be separated from the third unit electrode sheet (U).

[0112] The electrode assembly manufacturing process can be performed in a state where at least one end (front end) of a unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U). That is, the electrode assembly manufacturing process (e.g., winding process) can be performed in a state where one end of a unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U), and the electrode assembly manufacturing process (e.g., lamination process) can be performed in a state where both one end and the other end (rear end) of the unit electrode sheet (U) are separated from the neighboring unit electrode sheet (U).

[0113] Meanwhile, the unit electrode sheet (U) may have a first section (S1) of a longitudinal end (tip) on which a composite layer (54) is applied on one side of the electrode current collector (52) and on which the composite layer (54) is not applied on the other side (Fig. 2). When one end (tip) of the unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U), the one end (tip) of the unit electrode sheet (U) may be bent by the first section (S1) to one side in the thickness direction on which the composite layer (54) is not applied (Fig. 2). Here, the thickness direction may be the thickness direction of the electrode sheet (50). That is, a curl may be formed on one side (for example, the upper side) in the thickness direction at the end (tip) of the unit electrode sheet (U). This may be because a difference in elongation occurs between one side and the other side (e.g., the lower side) in the thickness direction of the unit electrode sheet (U) in the first section (S1).

[0114] As described above, the electrode assembly manufacturing process is performed in the state of FIG. 2 where at least one end (tip) of the unit electrode sheet (U) is separated from the neighboring unit electrode sheet (U), so when the unit electrode sheet (U) has the first section (S1), the electrode assembly manufacturing process described below may need to be performed in the state of FIG. 2 where a curl is formed at the tip of the unit electrode sheet (U).

[0115] At this time, the electrode assembly manufacturing process may not be performed or a manufacturing defect may occur due to the curl of the tip of the unit electrode sheet (U). For example, in a winding process for manufacturing a jelly roll-type electrode assembly by winding the unit electrode sheet (U) and the separator (70) together, the tip (core portion) of the unit electrode sheet (U) may i) not be inserted / injected into the winding core (300) due to the curl, and ii) even if inserted / injected into the winding core (300), the unit electrode sheet (U) may meander, resulting in a winding defect or a separation (cutting) defect at the rear end of the unit electrode sheet (U). Here, the winding core (300) will be described later.

[0116] Accordingly, the present invention provides a device and method for reducing curl of one end (tip) of a unit electrode sheet (U).

[0117]

[0118] [Curl reduction roller of electrode sheet]

[0119] Referring to FIG. 3, the curl reduction roller (100) of the electrode sheet according to one embodiment may include a first roller (110) and a second roller (120) or a second roller (120) and a third roller (130). The curl reduction roller (100) of the electrode sheet may reduce a curl that may be formed on one side of the electrode sheet (50) in the thickness direction, as shown in FIG. 2.

[0120] Here, the curl that can be formed on one side in the thickness direction of the electrode sheet (50) may mean a curl that is formed on one side in the thickness direction of the electrode sheet (50) when no external force (tension) is applied to the electrode sheet (50) before or after cutting the electrode sheet (50) (Fig. 2).

[0121] The first roller (110) and the second roller (120) or the second roller (120) and the third roller (130) can sequentially come into contact with the electrode sheet (50) being transported in the longitudinal direction. Here, the longitudinal direction may be the longitudinal direction of the electrode sheet (50). The first roller (110) and the second roller (120) or the second roller (120) and the third roller (130) can change the transport direction of the electrode sheet (50).

[0122] Each of the first roller (110) and the third roller (130) may contact the electrode sheet (50) along the outer circumference, but may contact the electrode sheet (50) so that it is bent to one side in the thickness direction.

[0123] The second roller (120) can be in contact with the electrode sheet (50) along the outer circumference, but can be in contact so that the electrode sheet (50) is bent to the other side in the thickness direction.

[0124] The second diameter (R2) of the second roller (120) may be greater than 0 and smaller than the first diameter (R1) of the first roller (110) and the third diameter (R3) of the third roller (130).

[0125] Accordingly, since the curvature of the second roller (120) is large, when the electrode sheet (50) is bent to the other side in the thickness direction by the second roller (120), the bending amount (bending angle) per unit length of the electrode sheet (50) can increase. Accordingly, the curl that can be formed in the electrode sheet (50) can be easily and effectively reduced at low cost with a simple configuration by the second roller (120).

[0126] In addition, since the curvature of the first and third rollers (110, 130) is small, when the electrode sheet (50) is bent in one direction in the thickness direction by the first roller (110) or the third roller (130), the bending amount per unit length of the electrode sheet (50) may be small. Accordingly, even if the electrode sheet (50) is bent by the first roller (110) or the third roller (130), a curl may not be formed in the electrode sheet (50) in one direction in the thickness direction or may be formed weakly.

[0127] In addition, since the first roller (110) is placed on the upstream side of the second roller (120) or the third roller (130) is placed on the downstream side, the bending amount of the electrode sheet (50) by the second roller (120) and the transport direction after bending of the electrode sheet (50) can be easily controlled.

[0128] Here, the upstream side and the downstream side may mean the upstream and the downstream in the transport path of the electrode sheet (50).

[0129] Meanwhile, the curl reduction roller (100) of the electrode sheet may include a first roller (110), a second roller (120), and a third roller (130). The first roller (110), the second roller (120), and the third roller (130) may sequentially come into contact with the electrode sheet (50) being transported in the longitudinal direction. The first roller (110), the second roller (120), and the third roller (130) may change the transport direction of the electrode sheet (50).

[0130] Accordingly, since the first roller (110) and the third roller (130) are respectively arranged on the upstream and downstream sides of the second roller (120), the bending amount of the electrode sheet (50) by the second roller (120) and the transport direction after bending of the electrode sheet (50) can be easily controlled.

[0131] The second bending angle (E2) at which the electrode sheet (50) is bent while contacting the outer circumference of the second roller (120) may be greater than or equal to the first bending angle (E1) and the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumferences of the first roller (110) and the third roller (130), respectively.

[0132] Accordingly, since the bending amount (bending angle) of the electrode sheet (50) in the thickness direction on the other side by the second roller (120) increases, curls that may be formed on the electrode sheet (50) in the thickness direction on one side can be effectively reduced.

[0133] The third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumference of the third roller (130) may be smaller than the first bending angle (E1) at which the electrode sheet (50) is bent while contacting the outer circumference of the first roller (110).

[0134] Accordingly, the degree to which the curl reduction effect by the second roller (120) is reduced / offset by the third roller (130) can be reduced.

[0135] The first roller (110), the second roller (120), and the third roller (130) can rotate around a virtual first axis (A1), a second axis (A2), and a third axis (A3) extending in the width direction, respectively. When the electrode sheet (50) comes into contact along the outer periphery of one side (e.g., the upper side) of the second roller (120) in a first direction (e.g., the vertical direction) perpendicular to the virtual plane including the first axis (A1) and the third axis (A3), the second axis (A2) can be located on one side relative to the first axis (A1) and the third axis (A3) (Fig. 3).

[0136] Accordingly, since the bending amount (bending angle) of the electrode sheet (50) in the thickness direction on the other side by the second roller (120) can be increased, curls that may be formed on the electrode sheet (50) in the thickness direction on one side can be effectively reduced.

[0137] In addition, since the distance between the first and third rollers (110, 130) can be reduced, the curl reduction roller of the electrode sheet (50) can be made smaller and lighter. In addition, since the distance between the first and second rollers (110, 120) and the distance between the second and third rollers (120, 130) can be increased, the electrode sheet (50) can be easily transported.

[0138] The second diameter (R2) may be greater than 0 and less than 3 / 5 of the diameter of each of the first diameter (D1) and the third diameter (D3).

[0139] Accordingly, since the diameter difference between the second roller (120) and the first and third rollers (110, 130) increases, curls that may be formed on the electrode sheet (50) can be effectively reduced by the second roller (120), and at the same time, even if the electrode sheet (50) is bent by the first roller (110) or the third roller (130), curls on the electrode sheet (50) may not be formed on one side in the thickness direction or may be formed weakly.

[0140] The third diameter (D3) may be greater than or equal to the first diameter (D1).

[0141] Accordingly, the degree to which the curl reduction effect by the second roller (120) is reduced / offset by the third roller (130) can be reduced.

[0142] The curl reduction roller (100) of the electrode sheet may include a fourth roller (140), a first roller (110), and a second roller (120).

[0143] The fourth roller (140), the first roller (110), and the second roller (120) can sequentially come into contact with the electrode sheet (50) being transported in the longitudinal direction. The fourth roller (140), the first roller (110), and the second roller (120) can change the transport direction of the electrode sheet (50).

[0144] The fourth roller (140) can be brought into contact with the electrode sheet (50) along the outer circumference, but can be brought into contact so that the electrode sheet (50) is bent to the other side in the thickness direction.

[0145] The fourth diameter (D4) of the fourth roller (140) may be greater than 0 and smaller than the first diameter (R1).

[0146] Accordingly, since the curvature of the fourth and second rollers (140, 120) is large, when the electrode sheet (50) is bent in the other direction in the thickness direction by the fourth and second rollers (140, 120), the bending amount (bending angle) per unit length of the electrode sheet (50) can increase. Accordingly, the curl that can be formed in the electrode sheet (50) can be easily and effectively reduced at low cost with a simple configuration by the fourth and second rollers (140, 120).

[0147] In addition, since the curvature of the first roller (110) is small, when the electrode sheet (50) is bent to one side in the thickness direction by the first roller (110), the bending amount per unit length of the electrode sheet (50) may be small. Accordingly, even if the electrode sheet (50) is bent by the first roller (110), a curl may not be formed on the electrode sheet (50) to one side in the thickness direction or may be formed weakly.

[0148] In addition, since the first roller (110) is placed on the downstream side of the fourth roller (140) and the upstream side of the second roller (120), the bending amount of the electrode sheet (50) by the fourth and second rollers (140, 120) can be easily controlled.

[0149] Meanwhile, the present invention can also be applied to an electrode in which a composite layer (54) is applied only to one side of the current collector (50) and curling occurs. The same applies hereinafter.

[0150]

[0151] [Electrode assembly manufacturing device]

[0152] Referring to FIG. 4, an electrode assembly manufacturing device (10) according to one embodiment may include a first winding machine (200), a curl reduction roller (100) of an electrode sheet, a core (300), a first conveying unit (400A), and a first cutter (500A). Here, the first winding machine (200), the first conveying unit (400A), and the first cutter (500A) may be the winding machine (200), the conveying unit (400), and the cutter (500) of the claims, respectively. The same applies hereinafter. The electrode assembly manufacturing device (10) may further include a second conveying unit (400B) and a second cutter (500B).

[0153] The first electrode sheet (200) can be unwound by the first electrode sheet (50A). Here, the first electrode sheet (50A) may be the electrode sheet (50) of the claim. The same applies hereinafter.

[0154] The curl reduction roller (100) of the electrode sheet can reduce curls that may be formed on one side of the thickness direction of the first electrode sheet (50A) by coming into contact with the first electrode sheet (50A).

[0155] The curl reduction roller (100) of the electrode sheet may be arranged downstream of the first winding machine (200) in the transport path of the first electrode sheet (50A), but upstream of the first cutter (500A).

[0156] The winding core (300) can rotate while the end of the first electrode sheet (50A) is fixed, thereby winding the first electrode sheet (50A). The winding core (300) can rotate while the ends of the first electrode sheet (50A), the second electrode sheet (50B), and the separator (70) are fixed together, thereby winding the first electrode sheet (50A), the second electrode sheet (50B), and the separator (70).

[0157] The first transfer unit (400A) can feed the first electrode sheet (50A) into the core (300). The second transfer unit (400B) can feed the second electrode sheet (50B) into the core (300).

[0158] The first cutter (500A) can cut the first electrode sheet (50A) fed into the core (300). The second cutter (500B) can cut the second electrode sheet (50B) fed into the core (300).

[0159] Accordingly, the curl (Fig. 2) that may be formed at the tip of the first electrode sheet (50A) after being cut by the first cutter (500A) is reduced by the curl reduction roller (100) of the electrode sheet, so that the tip (core portion) of the first electrode sheet (50A) can i) be easily and stably inserted / injected into the core (300), and ii) the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0160] The curl reduction roller (100) of the electrode sheet can be placed adjacent to the first winding machine (200).

[0161] Accordingly, the transport distance from the curl reduction roller (100) of the electrode sheet to the first cutter (500A) or the core (300) can be lengthened. Therefore, even if a reverse curl (a curl in the opposite direction to FIG. 2) in the thickness direction may be formed on the first electrode sheet (50A) by the curl reduction roller (100) of the electrode sheet, the reverse curl can be reduced by the tension applied to the first electrode sheet (50A) during the process of transporting the first electrode sheet (50A) to the first cutter (500A) or the core (300). Therefore, the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0162] The transport distance of the electrode sheet (50) from the first volume extractor (200) to the curl reduction roller (100) of the electrode sheet may be smaller than the transport distance of the electrode sheet (50) from the curl reduction roller (100) of the electrode sheet to the first cutter (500A).

[0163] Accordingly, the transport distance from the curl reduction roller (100) of the electrode sheet to the first cutter (500A) or the core (300) can be lengthened. Therefore, even if a reverse curl (a curl in the opposite direction to FIG. 2) in the thickness direction can be formed on the first electrode sheet (50A) by the curl reduction roller (100) of the electrode sheet, the reverse curl can be reduced by the tension applied to the first electrode sheet (50A) during the process of transporting the first electrode sheet (50A) to the first cutter (500A) or the core (300).

[0164]

[0165] [Electrode assembly manufacturing method]

[0166] Referring to FIG. 5, the electrode assembly manufacturing method (S900) may include a fixing process (S910), a winding process (S920), and a cutting process (S930).

[0167] In the fixing process (S910), the end of the first electrode sheet (50A) can be fixed to the core (300). Here, the first electrode sheet (50A) may be the electrode sheet (50) of the claim. The same applies hereinafter. In addition, the ends of the first electrode sheet (50A), the second electrode sheet (50B), and the separator (70) can be fixed to the core (300).

[0168] In the winding process (S920), the first electrode sheet (50A) can be wound by rotating the winding core (300). In addition, the first electrode sheet (50A), the second electrode sheet (50B), and the separator (70) can be wound together by rotating the winding core (300).

[0169] In the cutting process (S930), the first electrode sheet (50A) can be cut. In addition, the first electrode sheet (50A), the second electrode sheet (50B), and the separator (70) can each be cut.

[0170] When the first electrode sheet (50A) is transported in the winding process (S920), a curl that may be formed on one side of the first electrode sheet (50A) in the thickness direction can be reduced by the curl reduction roller (100) of the electrode sheet.

[0171] Accordingly, the curl (Fig. 2) that may be formed at the tip of the first electrode sheet (50A) after being cut by the first cutter (500A) is reduced by the curl reduction roller (100) of the electrode sheet, so that the tip (core portion) of the first electrode sheet (50A) can i) be easily and stably inserted / injected into the core (300), and ii) the first electrode sheet (50A) may not meander after being inserted / injected into the core (300), and a cutting defect of the first cutter (500A) may not occur.

[0172] In addition, when the first electrode sheet (50A) is transported in the fixing process (S910), a curl that may be formed on one side of the first electrode sheet (50A) in the thickness direction can be reduced by the curl reduction roller (100) of the electrode sheet.

[0173]

[0174] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow, rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all possible modifications and variations derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0175] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. An electrode sheet (50) extruder (200) for extruding the electrode sheet; A curl reduction roller (100) of the electrode sheet that reduces curl that may be formed on one side of the electrode sheet (50) in the thickness direction by coming into contact with the electrode sheet (50); A winding core (300) that rotates while the end of the electrode sheet (50) is fixed to wind the electrode sheet (50); A transfer unit (400) that feeds the electrode sheet (50) into the core (300); and It includes a cutter (500) that cuts the electrode sheet (50) that is fed into the above-mentioned core (300), The curl reduction roller (100) of the above electrode sheet is It includes a first roller (110) and a second roller (120) or a second roller (120) and a third roller (130) that sequentially contact the electrode sheet (50) being transported in the longitudinal direction and change the transport direction of the electrode sheet (50). Each of the first roller (110) and the third roller (130) contacts the electrode sheet (50) along the outer circumference, but contacts the electrode sheet (50) so that it is bent to one side in the thickness direction. The second roller (120) is in contact with the electrode sheet (50) along the outer circumference, but is in contact so that the electrode sheet (50) is bent to the other side in the thickness direction. The second diameter (R2) of the second roller (120) is greater than 0 and smaller than the first diameter (R1) of the first roller (110) and the third diameter (R3) of the third roller (130), The curl reduction roller (100) of the electrode sheet is arranged downstream of the winding machine (200) in the transport path of the electrode sheet (50), but upstream of the cutter (500). The transport distance of the electrode sheet (50) from the above-mentioned extruder (200) to the curl reduction roller (100) of the electrode sheet is smaller than the transport distance of the electrode sheet (50) from the curl reduction roller (100) of the electrode sheet to the cutter (500). Electrode assembly manufacturing device.

2. In claim 1, An electrode assembly manufacturing device in which the curl reduction roller (100) of the above electrode sheet is placed adjacent to the above winding machine (200).

3. In claim 1, An electrode assembly manufacturing device, wherein the curl reduction roller (100) of the electrode sheet includes the first roller (110), the second roller (120), and the third roller (130) that sequentially contact the electrode sheet (50) being transported in the longitudinal direction and change the transport direction of the electrode sheet (50).

4. In any one of claims 1 to 3, An electrode assembly manufacturing device, wherein the second bending angle (E2) at which the electrode sheet (50) is bent while contacting the outer circumference of the second roller (120) is greater than or equal to the first bending angle (E1) and the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumference of each of the first roller (110) and the third roller (130).

5. In claim 3, An electrode assembly manufacturing device, wherein the third bending angle (E3) at which the electrode sheet (50) is bent while contacting the outer circumference of the third roller (130) is smaller than the first bending angle (E1) at which the electrode sheet (50) is bent while contacting the outer circumference of the first roller (110).

6. In claim 3 or claim 5, The first roller (110), the second roller (120) and the third roller (130) rotate around a virtual first axis (A1), a second axis (A2) and a third axis (A3) extending in the width direction, respectively. An electrode assembly manufacturing device, wherein, in a first direction perpendicular to an imaginary plane including the first axis (A1) and the third axis (A3), when the electrode sheet (50) comes into contact along the outer circumference of one side of the second roller (120), the second axis (A2) is located on one side of the first axis (A1) and the third axis (A3).

7. In any one of claims 1 to 6, An electrode assembly manufacturing device, wherein the second diameter (R2) is greater than 0 and less than a value obtained by multiplying each of the first diameter (D1) and the third diameter (D3) by 3 / 5.

8. In claim 3, claim 5 or claim 7, An electrode assembly manufacturing device, wherein the third diameter (D3) is greater than or equal to the first diameter (D1).

9. In any one of claims 1 to 8, It includes a fourth roller (140) that sequentially contacts the electrode sheet (50) being transported in the longitudinal direction and changes the transport direction of the electrode sheet (50), and the first roller (110) and the second roller (120). The fourth roller (140) is in contact with the electrode sheet (50) along the outer circumference, but is in contact so that the electrode sheet (50) is bent to the other side in the thickness direction. An electrode assembly manufacturing device in which the fourth diameter (D4) of the fourth roller (140) is greater than 0 and smaller than the first diameter (R1).

10. In a method for manufacturing an electrode assembly (S900) using an electrode assembly manufacturing device (10) of any one of claims 1 to 9, A fixing process (S910) of fixing the end of the electrode sheet (50) to the core (300); A winding process (S920) for winding the electrode sheet (50) by rotating the above-mentioned winding core (300); and It includes a cutting process (S930) for cutting the above electrode sheet (50), When the electrode sheet (50) is transported in the above winding process (S920), the curl that may be formed on one side of the electrode sheet (50) in the thickness direction is reduced by the curl reduction roller (100) of the electrode sheet. Method for manufacturing an electrode assembly.

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