Rolling apparatus for manufacturing electrodes and rolling method for manufacturing electrodes

Abstract

A rolling apparatus for manufacturing an electrode according to one embodiment of the present invention includes a rolling unit that rolls an electrode substrate as the electrode substrate passes through, and a non-coating portion extension unit that additionally extends a non-coating portion of the electrode substrate that has passed through the rolling unit, wherein the non-coating portion extension unit is configured to adjust a relative position of the non-coating portion extension unit with respect to the electrode substrate depending on a state of the non-coating portion of the electrode substrate.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0165533 dated December 1, 2022 and Korean Patent Application No. 10-2023-0159672 dated November 17, 2023, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a rolling apparatus and a rolling method for manufacturing an electrode, and more particularly to a rolling apparatus and a rolling method for manufacturing an electrode that enable precise adjustment of additional stretching to an uncoated portion of an electrode substrate during an electrode rolling process. [Background technology]

[0003] In modern society, as the use of portable devices such as mobile phones, laptops, video cameras, and digital cameras has become commonplace, there has been active development of technologies related to these mobile devices. Furthermore, rechargeable secondary batteries are used as a power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and other vehicles as a way to address air pollution caused by existing gasoline-powered vehicles that use fossil fuels, and there is a growing need for the development of secondary batteries.

[0004] Currently commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Of these, lithium secondary batteries are attracting attention due to their advantages over nickel-based secondary batteries, such as almost no memory effect, freedom in charging and discharging, a very low self-discharge rate, and high energy density.

[0005] The manufacturing process of such lithium secondary batteries can be broadly divided into three steps: an electrode process, an assembly process, and a chemical formation process. The electrode process can be further divided into an active material mixing process, an electrode coating process, a rolling process, a slitting process, and a winding process. Among these, the rolling process is a process in which the electrode substrate is compressed to a desired thickness by passing it between a pair of rolls heated to a high temperature in order to reduce the thickness of the electrode substrate after the coating process, thereby increasing the capacity density and increasing the adhesion between the electrode current collector and the electrode active material.

[0006] However, when the electrode substrate is rolled, the difference in extensibility between the holding portion 12 coated with an active material and the uncoated portion 11 not coated with an active material can cause a problem such as waviness in the uncoated portion 11 of the electrode substrate after rolling. To address this issue, referring to FIG. 1, the uncoated portion 11 of the electrode substrate 10 that has passed through the rolling portion 110 is subjected to additional stretching by the uncoated portion stretching portion 120. However, although the tension applied to the uncoated portion 11 of the electrode substrate by the uncoated portion stretching portion 120 can improve the waviness of the uncoated portion 11, it can also worsen the waviness in some cases.

[0007] Therefore, a more effective solution to the problem of undulations occurring in the uncoated portion 11 of the electrode substrate during the rolling process of the electrode substrate is required. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention aims to alleviate the problem of waviness in the uncoated portion 11 of the electrode substrate by additionally stretching the uncoated portion 11 during the rolling process of the electrode substrate and adjusting the degree of stretching.

[0009] However, the problems to be solved by the embodiments of the present invention are not limited to the above problems, and can be variously expanded within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0010] A rolling apparatus for manufacturing an electrode according to one embodiment of the present invention includes a rolling unit that rolls an electrode substrate as the electrode substrate passes through, and a non-coating portion extension unit that additionally extends a non-coating portion of the electrode substrate that has passed through the rolling unit, wherein the non-coating portion extension unit is configured to adjust a relative position of the non-coating portion extension unit with respect to the electrode substrate depending on a state of the non-coating portion of the electrode substrate.

[0011] The non-coating portion may further include a driving unit for adjusting the position of the non-coating portion extension unit, and the non-coating portion extension unit may be configured to maintain its position, move forward toward the electrode substrate, or move backward from the electrode substrate in the opposite direction, thereby adjusting the position of the non-coating portion extension unit.

[0012] The electrode substrate may further include a monitoring unit that monitors the electrode substrate and determines a state of the uncoated portion of the electrode substrate. When the uncoated portion of the electrode substrate is in a normal state, the uncoated portion extension portion may maintain its position. When the uncoated portion of the electrode substrate is in a predetermined first abnormal state, the uncoated portion extension portion may advance toward the electrode substrate. When the uncoated portion of the electrode substrate is in a predetermined second abnormal state, the uncoated portion extension portion may retreat from the electrode substrate.

[0013] The first abnormal state may be a state in which a valley or ridge of the undulations of the uncoated portion occurs in the longitudinal direction of the electrode substrate, and the second abnormal state may be a state in which a valley or ridge of the undulations of the uncoated portion occurs in the width direction of the electrode substrate.

[0014] If the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is greater than 0 degrees and less than 45 degrees, the uncoated area is determined to be in a first abnormal state; if the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is greater than 45 degrees and less than 90 degrees, the uncoated area is determined to be in a second abnormal state; and if the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is 45 degrees, the uncoated area is determined to be in either the first abnormal state or the second abnormal state.

[0015] When the uncoated portion of the electrode substrate is in a predetermined first abnormal state, the uncoated portion extension portion advances toward the electrode substrate by a first predetermined value, and the advancement of the uncoated portion extension portion by the first predetermined value is repeated until the uncoated portion of the electrode substrate is determined to be in a normal state.

[0016] If the uncoated portion of the electrode substrate is in a predetermined second abnormal state, the uncoated portion extension portion is moved backward from the electrode substrate by a second predetermined value, and the backward movement of the uncoated portion extension portion by the second predetermined value is repeated until the uncoated portion of the electrode substrate is determined to be in a normal state.

[0017] The monitoring unit is positioned downstream of the non-coating portion extension section and is configured to monitor the state of the non-coating portion of the electrode substrate that has passed through the non-coating portion extension section, and adjust the position of the non-coating portion extension section accordingly.

[0018] The monitoring unit is located between the rear of the rolling section and the front of the plain portion extension section, and is configured to monitor the state of the plain portion of the electrode substrate that has passed through the rolling section, and adjust the position of the plain portion extension section accordingly.

[0019] The rolling unit may be a pair of rolling rollers that rotate in opposite directions around a rotation axis, and the plain-area stretching unit may be a plain-area pressure roller including a pressure unit, and the pressure unit may be provided at a position corresponding to the plain area of ​​the electrode substrate and have a structure that protrudes from the outer circumferential surface of the plain-area pressure roller.

[0020] The driving unit may be an actuator connected to the non-coating pressure roller.

[0021] The electrode substrate may further include a guide portion for guiding the movement of the electrode substrate.

[0022] The electrode assembly may further include an electrode rewinder that winds and recovers the electrode substrate.

[0023] A rolling method for manufacturing an electrode according to an embodiment of the present invention includes: rolling an electrode substrate in a rolling unit; additionally extending a non-coating portion of the rolled electrode substrate in a non-coating portion extension unit; and monitoring the electrode substrate with a monitoring unit to determine a state of the non-coating portion of the electrode substrate. If the state of the non-coating portion of the electrode substrate is abnormal, the method may further include adjusting a position of the non-coating portion extension unit relative to the electrode substrate.

[0024] When the uncoated portion of the electrode substrate is in a normal state, the uncoated portion extension can maintain its position.

[0025] The step of adjusting the relative position of the non-coating portion extension portion may include at least one of the steps of: when the non-coating portion of the electrode substrate is in a predetermined first abnormal state, the non-coating portion extension portion moving forward toward the electrode substrate; and when the non-coating portion of the electrode substrate is in a predetermined second abnormal state, the non-coating portion extension portion moving backward from the electrode substrate.

[0026] The first abnormal state may be a state in which a valley or ridge of the undulations of the uncoated portion occurs in the longitudinal direction of the electrode substrate, and the second abnormal state may be a state in which a valley or ridge of the undulations of the uncoated portion occurs in the width direction of the electrode substrate.

[0027] If the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is greater than 0 degrees and less than 45 degrees, the uncoated area is determined to be in a first abnormal state; if the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is greater than 45 degrees and less than 90 degrees, the uncoated area is determined to be in a second abnormal state; and if the angle between the direction of the undulation valleys or ridges of the uncoated area and the direction of travel of the electrode substrate is 45 degrees, the uncoated area is determined to be in either the first abnormal state or the second abnormal state.

[0028] When the uncoated portion of the electrode substrate is in a predetermined first abnormal state, the uncoated portion extension portion advances toward the electrode substrate by a first predetermined value, and the advancement of the uncoated portion extension portion by the first predetermined value is repeated until the uncoated portion of the electrode substrate is determined to be in a normal state.

[0029] If the uncoated portion of the electrode substrate is in a predetermined second abnormal state, the uncoated portion extension portion is moved backward from the electrode substrate by a second predetermined value, and the backward movement of the uncoated portion extension portion by the second predetermined value is repeated until the uncoated portion of the electrode substrate is determined to be in a normal state. [Effects of the Invention]

[0030] According to the present invention, the problem of waviness in the uncoated portion 11 can be more effectively alleviated by additionally extending the uncoated portion 11 of the electrode substrate during the rolling process of the electrode substrate and adjusting the position of the uncoated portion extension, thereby maximizing the production efficiency of the electrode assembly and improving the quality of the produced electrode assemblies.

[0031] The effects of the present invention are not limited to those mentioned above, and effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawings]

[0032] [Figure 1] 1 shows a prior art rolling mill for manufacturing electrodes. [Figure 2] 1 shows a rolling mill for manufacturing electrodes according to an embodiment of the present invention; [Figure 3] FIG. 2 is a schematic view showing a part of an electrode base material. [Figure 4] 3 shows a non-coating portion rolling roller provided in the electrode manufacturing rolling device of FIG. 2. [Figure 5] An example will be shown in which the degree of forward and backward movement of the plain-area extending portion in FIG. 2 is set as a process variable of the wrap angle (θ). [Figure 6] An example of an abnormal state in an uncoated portion of an electrode substrate is shown. [Figure 7]An example of an abnormal state in an uncoated portion of an electrode substrate is shown. [Figure 8] 10 shows a rolling mill for manufacturing an electrode according to another embodiment of the present invention, which is a modified example of the rolling mill for manufacturing an electrode shown in FIG. [Figure 9] 1 shows a flow chart of a rolling method for manufacturing an electrode according to one embodiment of the present invention. [Figure 10] 1 shows a flow chart of a rolling method for manufacturing an electrode according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0033] The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a semiconductor device according to an embodiment of the present invention; FIG. 2 is a block diagram of a semiconductor device according to an embodiment of the present invention; FIG. 3 is a block diagram of a semiconductor device according to an embodiment of the present invention;

[0034] In order to clearly explain the present invention, parts that are not necessary for the explanation will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0035] In addition, the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to those shown in the drawings. In the drawings, thicknesses are exaggerated to clearly show various layers and regions. In the drawings, thicknesses of some layers and regions are exaggerated for the convenience of explanation.

[0036] Furthermore, when a layer, film, region, plate, or other part is said to be "above" another part, this does not only mean that it is "directly above" that part, but also includes cases where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Note that being "above" a reference part means being located above or below the reference part, and does not necessarily mean being "above" in the opposite direction of gravity.

[0037] Furthermore, throughout the specification, when a part is described as "comprising" a certain element, this means that it can further include other elements, rather than excluding other elements, unless otherwise specified.

[0038] Furthermore, throughout the specification, "in a plane" means a view of the subject matter as viewed from above, and "in cross section" means a view of the subject matter as viewed from the side across a vertical cross section.

[0039] Hereinafter, a rolling apparatus 100 for electrode production according to one embodiment of the present invention will be described with reference to FIGS.

[0040] The electrode manufacturing rolling apparatus 100 of FIG. 2 includes a rolling section 110, a non-coating section stretching section 120, a monitoring unit 130, a guide section 140, and an electrode rewinder 150.

[0041] As shown in Fig. 3, the electrode substrate 10 has a structure in which one or both surfaces of a current collector made of aluminum foil or the like are coated with an electrode mixture, i.e., has a holding section 12 (see Fig. 3). The electrode substrate 10 passes through a rolling section 110 and is rolled.

[0042] The rolling unit 110 may be, for example, a pair of rolling rollers. The rolling rollers rotate in opposite directions around a rotation axis located at the center of each rolling roller and extending in the longitudinal direction of the roller. When the electrode substrate 10 passes between the rolling rollers, the holding unit 12 is rolled.

[0043] At this time, undulations may occur in the uncoated portion 11 of the electrode substrate 10 that has passed through the rolling section 110 .

[0044] Thereafter, the non-coating portion 11 of the electrode substrate 10 is stretched by a non-coating portion stretching unit 120 disposed subsequent to the rolling unit 110. More specifically, as shown in FIG. 4, the non-coating portion stretching unit 120 may be, for example, a pressure roller. In addition, to solve the problem of undulations occurring in the non-coating portion 11, a pressure unit 120a may be included to pressurize only the non-coating portion 11 of the electrode substrate 10.

[0045] The pressing portion 120a of the non-coating portion extension 120 is formed at a position corresponding to the non-coating portion 11 of the electrode substrate 10. The pressing portion 120a protrudes from the outer periphery of the non-coating portion extension 120. This allows the pressing portion 120a of the non-coating portion extension 120 to press only the non-coating portion 11, excluding the holding portion 12 of the electrode substrate 10.

[0046] The pressure applying portion 120a of the plain portion stretching portion 120 may be formed integrally with the roller body of the plain portion stretching portion 120, or may be detachably attached to the outer peripheral surface of the plain portion stretching portion 120 by a shrink fit method.

[0047] Furthermore, the pressure unit 120a may include a heat ray therein for applying heat to the uncoated portion 11 in order to effectively roll the uncoated portion 11.

[0048] The width of the pressure applying portion 120a is the same as or slightly smaller than the width of the uncoated portion 11 of the electrode substrate 10. For example, the pressure applying portion 120a may have a width that is 90% to 100% of the width of the uncoated portion 11.

[0049] The plain portion extension 120 is made of any one of metals such as aluminum, its alloys, or stainless steel, or plastic materials such as high-strength and high-hardness engineering plastic materials, low-hardness plastic materials, or rubber materials.

[0050] The uncoated portion extension 120 can rotate in the direction of travel of the electrode substrate 10 around a rotation axis that is in the longitudinal direction at the center of the uncoated portion extension 120 .

[0051] Meanwhile, both ends of the non-coating portion extending portion 120 are connected to a driving unit (not shown) that can adjust the position of the non-coating portion extending portion 120. The driving unit may be, for example, an actuator that adjusts the position of the non-coating portion extending portion 120. The driving unit may move the non-coating portion extending portion 120 forward (A1) toward the electrode substrate 10, or conversely, move the non-coating portion extending portion 120 backward (A2) from the electrode substrate 10.

[0052] For example, bar-shaped support parts may be connected to both ends of the non-coating portion extension part 120 in the direction of the rotation axis of the non-coating portion extension part 120, and the drive part may move the non-coating portion extension part 120 and the support parts forward (A1) toward the electrode substrate 10, or conversely, move them backward (A2) from the electrode substrate 10.

[0053] The condition (e.g., the degree of waviness improvement) of the uncoated portion 11 of the electrode substrate 10 stretched by the uncoated portion stretching unit 120 is monitored by the monitoring unit 130. The monitoring unit 130 may be, for example, a vision unit that captures an image of the condition of the uncoated portion 11 of the electrode substrate 10.

[0054] The monitoring unit 130 monitors the state of the uncoated portion 11 and determines the state of the uncoated portion 11 using a processor 130a that is either integrated into the monitoring unit 130 or separately provided and connected thereto. The monitoring unit 130 can, for example, determine whether the state of the uncoated portion 11 of the electrode substrate 10 is normal or abnormal (abnormal).

[0055] The non-coating portion extension 120 is configured such that the relative position of the non-coating portion extension 120 with respect to the electrode substrate 10 is adjusted according to the state of the non-coating portion 11 of the electrode substrate 10 .

[0056] If the state of the non-coating portion 11 of the electrode substrate 10 corresponds to a normal state, the position of the non-coating portion extension portion 120 is maintained without any change, and pressure is applied to the non-coating portion 11 as is. Here, the normal state of the non-coating portion 11 means that, when the non-coating portion 11 of the electrode substrate is monitored by the monitoring unit 130, no undulations or the like occur in the non-coating portion 11, and the flatness of the holding portion 12 and the flatness of the non-coating portion 11 are the same or within a tolerance range. The extent to which the holding portion 12 and the non-coating portion 11 are extended in the electrode substrate are within a tolerance range. However, if the state of the non-coating portion 11 of the electrode substrate 10 corresponds to an abnormal (non-normal) state, the position of the non-coating portion extension portion 120 is adjusted by the driving unit.

[0057] If the state of the non-coating portion 11 of the electrode substrate 10 is determined to be a predetermined first abnormal state among abnormal (non-normal) states, the driver advances (A1) the non-coating portion extending portion 120 toward the electrode substrate 10. Alternatively, if the state of the non-coating portion 11 of the electrode substrate 10 is determined to be a predetermined second abnormal state among abnormal (non-normal) states, the driver advances (A2) the non-coating portion extending portion 120 in the opposite direction away from the electrode substrate 10. In other words, if undulation occurs in the non-coating portion 11 of the electrode substrate 10 after passing through the rolling unit 110, the non-coating portion extending portion 120 further extends the non-coating portion 11 to resolve the undulation. At this time, the monitoring unit 130 monitors the state of the non-coating portion 11 of the electrode substrate 10 during processing and adjusts the position of the non-coating portion extending portion 120 accordingly to adjust the degree of further extension of the non-coating portion 11. Depending on various process variables such as the type of electrode current collector and electrode mixture, the transport speed of the electrode substrate 10, and the degree of rolling by the rolling section 110, the degree of waviness of the plain portion 11 may be improved by advancing the plain portion extension section 120 toward the electrode substrate 10 (A1). Conversely, the degree of waviness of the plain portion 11 may be improved by moving the plain portion extension section 120 backward from the electrode substrate 10 (A2) to reduce the degree of stretching applied to the plain portion 11.

[0058] In other words, a predetermined first abnormal state, a predetermined second abnormal state, and a normal state can be preset to suit various environments in which the present invention is realized, and the position of the plain portion extension portion 120 can be adjusted accordingly.

[0059] In addition, the extent to which the non-coating portion extension portion 120 moves forward (A1) and / or backward (A2) can be more specifically preset to suit various environments in which the present invention is implemented, thereby enabling precise position adjustment of the non-coating portion extension portion 120.

[0060] Meanwhile, the present invention is not limited to the non-coating portion 11 of the electrode substrate 10 shown in FIG. 3 , and similarly, the non-coating portion extension 120 is not limited to the non-coating portion extension 120 shown in FIG. The non-coating portion 11 and the non-coating portion extension 120 of the electrode substrate 10 can be variously modified and changed to suit various environments and situations in which the present invention is realized. In some cases, the degree to which the non-coating portion extension 120 advances (A1) and / or retreats (A2) may be set as a process variable for the wrap angle (θ), and the degree of that angle may be adjusted. The wrap angle refers to the angle that surrounds a portion of the non-coating portion extension 120 when the electrode substrate 10 contacts the non-coating portion extension 120, as shown in FIG. 5 .

[0061] 6 and 7 each show an example of an abnormal (abnormal) state of the uncoated portion 11. The portion of the electrode substrate 10 shown in FIG. 3 enclosed by the dotted line is enlarged to show a top view, a side view, and a cross-sectional view of the electrode substrate 10, respectively. The arrow indicates the direction in which the electrode substrate 10 advances during the process, but this does not necessarily mean that the direction of advancement is upward in the drawing. It is sufficient for the electrode substrate 10 to advance in the longitudinal direction of the electrode substrate 10, taking into account the various environments in which the present invention is applied.

[0062] First, an example of the predetermined first abnormal state is when undulations in the uncoated portion 11 are formed along the traveling direction of the electrode substrate 10, as shown in Fig. 6. This is the case when extension lines extending along the valleys of the undulations (direction of the valleys of the undulations) and / or extension lines extending along the ridges of the undulations (direction of the ridges of the undulations) are formed along the traveling direction of the electrode substrate 10.

[0063] This occurs when the extent to which the non-coating portion 11 is stretched is less than the extent to which the holding portion 12 is stretched. In other words, if the non-coating portion 11 is stretched by the non-coating portion stretching portion 120 but is not stretched sufficiently to the extent that the holding portion 12 is stretched, undulations will form in the taut non-coating portion 11 in the direction of travel of the electrode substrate 10.

[0064] Furthermore, the valleys of the undulations become deeper or thinner depending on the relative degree of stretch of the plain portion 11 with respect to the holding portion 12. The smaller the difference between the degree of stretch of the plain portion 11 and the degree of stretch of the holding portion 12 (i.e., the absolute value of the difference between the degree of stretch of the plain portion 11 and the degree of stretch of the holding portion 12), the thinner the valleys of the undulations become, and when the degree of stretch of the holding portion 12 and the degree of stretch of the plain portion 11 become the same within the tolerance range, the undulations of the plain portion 11 disappear.

[0065] On the other hand, not only may the direction of the undulation valleys and / or ridges of the uncoated portion 11 coincide with the traveling direction of the electrode substrate 10, but depending on the type of electrode substrate and the process environment, the direction of the undulation valleys and / or ridges of the uncoated portion 11 may have an oblique inclination angle relative to the traveling direction of the electrode substrate 10, and therefore the angle between the direction of the undulation valleys and / or ridges of the uncoated portion 11 and the traveling direction of the electrode substrate 10 may be formed within a range of 0 degrees or more and 45 degrees or less.

[0066] In summary, the monitoring unit 130 monitors the direction of the valleys and / or ridges of the undulations of the uncoated portion 11, and if they are formed along the traveling direction of the electrode substrate 10, it is determined that a first abnormal state has occurred.

[0067] In addition, the meaning that the direction of the undulation valleys and / or ridges of the uncoated portion 11 is formed along the traveling direction of the electrode substrate 10 is determined to be a first abnormal state when the angle between the direction of the undulation valleys and / or ridges of the uncoated portion 11 and the traveling direction of the electrode substrate 10 is between 0 degrees and 45 degrees.

[0068] When the state of the uncoated portion 11 of the electrode substrate 10 is determined to be the first abnormal state, the uncoated portion extension 120 advances toward the electrode substrate 10 side.

[0069] 7, an example of the predetermined second abnormal state is when undulations in the uncoated portion 11 are formed along the width direction of the electrode substrate 10 (a direction perpendicular to the traveling direction of the electrode substrate 10). This is the case when extension lines extending along the valleys of the undulations (direction of the valleys of the undulations) and / or extension lines extending along the ridges of the undulations (direction of the ridges of the undulations) are formed along the width direction of the electrode substrate 10.

[0070] This occurs when the extent to which the non-coating portion 11 is stretched is greater than the extent to which the holding portion 12 is stretched. In other words, if the non-coating portion 11 is stretched by the non-coating portion stretching portion 120 but is actually stretched more than the holding portion 12, undulations will form in the width direction of the electrode substrate 10 in the non-coating portion 11, which has become relatively longer.

[0071] Furthermore, the undulation grooves become deeper or thinner depending on the relative degree of stretch of the plain portion 11 with respect to the holding portion 12. The smaller the difference between the degree of stretch of the plain portion 11 and the degree of stretch of the holding portion 12 (i.e., the absolute value of the difference between the degree of stretch of the plain portion 11 and the degree of stretch of the holding portion 12), the thinner the undulation valleys become, and when the degree of stretch of the holding portion 12 and the degree of stretch of the plain portion 11 become the same within the tolerance range, the undulation of the plain portion 11 disappears.

[0072] Meanwhile, not only may the direction of the undulation valleys and / or ridges of the uncoated portion 11 be perpendicular to the traveling direction of the electrode substrate 10, but depending on the type of electrode substrate and the process environment, the direction of the undulation valleys and / or ridges of the uncoated portion 11 may have an inclination angle oblique to the direction perpendicular to the traveling direction of the electrode substrate 10, and therefore the angle between the direction of the undulation valleys and / or ridges of the uncoated portion 11 and the traveling direction of the electrode substrate 10 may be within the range of 45 degrees or more and 90 degrees or less.

[0073] In summary, the direction of the valleys and / or ridges of the undulations of the uncoated portion 11 is monitored by the monitoring unit 130, and if they are formed along the width direction of the electrode substrate 10, it is determined that a second abnormal state has occurred.

[0074] In addition, the meaning that the direction of the undulation valleys and / or ridges of the uncoated portion 11 is formed along the width direction of the electrode substrate 10 is determined to be a second abnormal state when the angle between the direction of the undulation valleys and / or ridges of the uncoated portion 11 and the traveling direction of the electrode substrate 10 is 45 degrees or more and 90 degrees or less.

[0075] If the state of the uncoated portion 11 of the electrode substrate 10 is determined to be the second abnormal state, the uncoated portion extension 120 moves backward from the electrode substrate 10.

[0076] For reference, when the undulation valleys and / or ridges of the non-coating portion 11 form a 45-degree angle with respect to the traveling direction of the electrode substrate 10, whether to move the non-coating portion extension portion 120 forward (A1) or backward (A2) is predetermined to suit the environment and depends on various process variables such as the type of electrode current collector and electrode mixture, the transport speed of the electrode substrate 10, and the degree of rolling by the rolling portion 110. In other words, when the angle between the direction of the undulation valleys and / or ridges of the non-coating portion 11 and the traveling direction of the electrode substrate 10 is 45 degrees, either the first abnormal state or the second abnormal state is determined depending on the environment in which the present invention is realized, such as the type of electrode substrate 10 and the process environment.

[0077] Meanwhile, the extent to which the non-coating portion extending portion 120 advances toward the electrode substrate 10 when the state of the non-coating portion 11 of the electrode substrate 10 is determined to be the first abnormal state, and the extent to which the non-coating portion extending portion 120 retreats from the electrode substrate 10 when the state of the non-coating portion 11 of the electrode substrate 10 is determined to be the second abnormal state, may each be predetermined based on the type of electrode substrate 10 and / or the process environment. In addition, the extent to which the non-coating portion extending portion 120 advances and the extent to which it retreats are predetermined to first and second predetermined values, respectively.

[0078] If the condition of the non-coating portion 11 of the electrode substrate 10 monitored by the monitoring unit 130 is determined to be a first abnormal state, the result is fed back to the non-coating portion extension portion 120, thereby causing the non-coating portion extension portion 120 to advance toward the electrode substrate 10 by a first predetermined value.

[0079] The monitoring unit 130 monitors the non-coating portion 11 of the electrode substrate 10 stretched in the non-coating portion stretching unit 120 following the forward / backward movement of the non-coating portion stretching unit 120. Alternatively, regardless of this, the monitoring unit 130 may continuously monitor the non-coating portion 11 of the electrode substrate 10 stretched in the non-coating portion stretching unit 120.

[0080] If the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching portion 120, which has advanced by the first predetermined value, is still determined to be in the first abnormal state, the result is fed back to the non-coating portion stretching portion 120, and the non-coating portion stretching portion 120 again advances by the first predetermined value toward the electrode substrate 10.

[0081] If the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching portion 120, which has advanced by the first predetermined amount, is determined to be normal, the non-coating portion stretching portion 120 maintains its position without moving forward or backward.

[0082] Rather, if the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching portion 120, which has advanced by a first predetermined value, is determined to be a second abnormal state, the result is fed back to the non-coating portion stretching portion 120, and the non-coating portion stretching portion 120 moves backward from the electrode substrate 10 by a second predetermined value.

[0083] The above process is repeated until the state of the uncoated portion 11 of the electrode substrate 10 stretched in the uncoated portion stretching unit 120 is determined to be normal.

[0084] Similarly, if the condition of the uncoated portion 11 of the electrode substrate 10 monitored by the monitoring unit 130 is determined to be a second abnormal state, the result is fed back to the uncoated portion extension portion 120, causing the uncoated portion extension portion 120 to move backward from the electrode substrate 10 by a second predetermined value.

[0085] If the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching unit 120, which has moved backward by the second predetermined value, is still determined to be in the second abnormal state, the result is fed back to the non-coating portion stretching unit 120, and the non-coating portion stretching unit 120 again moves forward by the second predetermined value from the electrode substrate 10.

[0086] If the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching portion 120, which has moved backward by the second predetermined amount, is determined to be normal, the non-coating portion stretching portion 120 maintains its position without moving forward or backward.

[0087] Rather, if the state of the non-coating portion 11 of the electrode substrate 10 stretched by the non-coating portion stretching portion 120, which has moved backward by the second predetermined value, is determined to be in the first abnormal state, the result is fed back to the non-coating portion stretching portion 120, and the non-coating portion stretching portion 120 moves forward by the first predetermined value toward the electrode substrate 10.

[0088] The above process is repeated until the state of the uncoated portion 11 of the electrode substrate 10 stretched in the uncoated portion stretching unit 120 is determined to be normal.

[0089] In addition, the first predetermined value and the second predetermined value can be preset in various ways depending on the type of electrode substrate 10 in which the present invention is realized and the process environment (various process variables such as the type of electrode current collector and electrode mixture, the transport speed of the electrode substrate 10, and the degree of rolling by the rolling section 110).

[0090] FIG. 8 shows a modified example of the rolling mill for manufacturing electrodes shown in FIG.

[0091] 2, the monitoring unit 130 is located after the non-coating portion extending section 120. As a result, the monitoring unit 130 monitors the electrode substrate 10 that has passed through the non-coating portion extending section 120 and adjusts the position of the non-coating portion extending section 120 to adjust the degree of waviness of the non-coating portion 11 of the electrode substrate 10 that subsequently enters the non-coating portion extending section 120.

[0092] 8, a monitoring unit 130 is located between the rear of the rolling section 110 and the front of the non-coating section extension section 120. This monitors the electrode substrate 10 that has passed through the rolling section 110 and adjusts the position of the non-coating section 120.

[0093] As described above with reference to FIG. 2, the method of monitoring the electrode substrate 10 and adjusting the position of the non-coating portion extension portion 120 can be achieved by presetting a predetermined first abnormal state, a predetermined second abnormal state, and a normal state in accordance with the various environments in which the present invention is implemented, and adjusting the position of the non-coating portion extension portion 120 accordingly.

[0094] Hereinafter, a rolling method for manufacturing an electrode according to one embodiment of the present invention will be described with reference to FIGS.

[0095] 9, a rolling method for manufacturing an electrode according to an embodiment of the present invention includes step S110 of rolling an electrode substrate in a rolling unit 110, step S120 of additionally extending the uncoated portion 11 of the rolled electrode substrate 10 in the uncoated portion extending unit 120, and step S130 of monitoring the electrode substrate in a monitoring unit 130 to determine the state of the uncoated portion of the electrode substrate. In the embodiment of FIG. 2, step S130 is performed subsequent to step S120. Alternatively, in the embodiment of FIG. 8, step S120 may be performed after step S130. The apparatus according to the embodiment of FIG. 2 will now be described with reference to FIG. 10.

[0096] In step S130, it is determined whether the state of the uncoated area is normal. If it is determined that the state of the uncoated area is abnormal, step S130 includes step S131, in which it is determined whether the state of the uncoated area is a first abnormal state or a second abnormal state. If it is determined that the state of the uncoated area is abnormal, step S131 determines whether the direction of the undulations in the uncoated area is formed in the traveling direction of the electrode substrate or in the width direction of the electrode substrate. A more detailed explanation of whether the state of the uncoated area is the first abnormal state or the second abnormal state overlaps with the explanation given above with reference to FIGS. 1 to 7, so please refer to the explanation given above.

[0097] The method includes a step S140 of adjusting the relative position of the non-coating portion extension portion with respect to the electrode substrate by the driving unit according to the state of the non-coating portion 11 of the electrode substrate monitored by the monitoring unit.

[0098] If it is determined in step S130 that the non-coating portion of the electrode substrate is in a normal state, the non-coating portion extension portion maintains its position.

[0099] Step S140 includes step S141, in which the non-coating portion extending portion advances toward the electrode substrate by a first predetermined value if the non-coating portion of the electrode substrate is determined to be in a predetermined first abnormal state in step S130 (step S131). Step S140 may also include step S142, in which the non-coating portion extending portion retreats from the electrode substrate by a second predetermined value if the non-coating portion of the electrode substrate is determined to be in a predetermined second abnormal state in step S130 (step S131). Step S140, in which the relative position of the non-coating portion extending portion is adjusted, is repeated until the state of the non-coating portion of the electrode substrate is determined to be normal.

[0100] In one embodiment, the electrode refers to the positive electrode and / or negative electrode of a lithium secondary battery.

[0101] The positive electrode has a structure in which a two-layer positive electrode active material layer is laminated on a positive electrode current collector. In one example, the positive electrode active material layer includes a positive electrode active material, a conductive material, a binder polymer, etc., and may further include a positive electrode additive commonly used in the art, as needed.

[0102] The positive electrode active material may be a lithium-containing oxide, which may be the same or different. As the lithium-containing oxide, a lithium-containing transition metal oxide can be used.

[0103] For example, lithium-containing transition metal oxides include Li x CoO2(0.5 <x<1.3)、Li x NiO2(0.5 <x<1.3)、Li x MnO2(0.5 <x<1.3)、Li x Mn2O4(0.5 <x<1.3)、Li x (Ni a Co b Mn c )O2(0.5 <x<1.3、0<a<1、0<b<1、0<c<1、a+b+c=1)、Li x Ni 1-y Co y O2(0.5 <x<1.3、0<y<1)、Li x Co 1-y Mn yO2 (0.5 < x < 1.3, 0 ≤ y < 1), Li x Ni 1-y Mn y O2 (0.5 < x < 1.3, 0 ≤ y < 1), Li x (Ni a Co b Mn c )O4 (0.5 < x < 1.3, 0 < a < 2, 0 < b < 2, 0 < c < 2, a + b + c = 2), Li x Mn 2-z Ni z O4 (0.5 < x < 1.3, 0 < z < 2), Li x Mn 2-z Co z O4 (0.5 < x < 1.3, 0 < z < 2), Li x CoPO4 (0.5 < x < 1.3) and Li x Any one selected from the group consisting of FePO4 (0.5 < x < 1.3) or a mixture of two or more of these may be used, and the lithium-containing transition metal oxide may be coated with a metal or metal oxide such as aluminum (Al). In addition to the lithium-containing transition metal oxide, one or more selected from the group consisting of sulfide, selenide, and halide can also be used.

[0104] The positive electrode active material is contained in the positive electrode active material layer in the range of 94.0 to 98.5% by weight. When the content of the positive electrode active material satisfies the above range, it is advantageous in terms of manufacturing a high-capacity battery and imparting sufficient conductivity of the positive electrode and adhesion between electrode materials.

[0105] The current collector used for the positive electrode can be any metal with high conductivity, a metal to which the positive electrode active material slurry can easily adhere, and a metal that is non-reactive within the voltage range of the electrochemical device. Specifically, non-limiting examples of the current collector for the positive electrode include foils made of aluminum, nickel, or combinations thereof.

[0106] The positive electrode active material layer further contains a conductive material. The conductive material is typically added in an amount of 1 to 30 wt % based on the total weight of the mixture containing the positive electrode active material. There are no particular limitations on the conductive material, as long as it is conductive and does not induce chemical changes in the secondary battery. For example, the conductive material may be one or more selected from the group consisting of graphite such as natural graphite and artificial graphite; carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fiber and metal fiber; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and polyphenylene derivatives.

[0107] The negative electrode has a structure in which a two-layer negative electrode active material layer is laminated on a negative electrode current collector. In one example, the negative electrode active material layer includes a negative electrode active material, a conductive material, a binder polymer, etc., and may further include a negative electrode additive commonly used in the art, as needed.

[0108] The negative electrode active material may include carbon, lithium metal, silicon, or tin. When a carbon material is used as the negative electrode active material, both low-crystalline and high-crystalline carbons can be used. Typical low-crystalline carbons include soft carbon and hard carbon, while typical high-crystalline carbons include one or more high-temperature-calcined carbons selected from the group consisting of natural graphite, kish graphite, pyrolytic carbon, mesophase pitch-based carbon fiber, carbon microbeads, mesophase pitches, and petroleum or coal tar pitch-derived cokes.

[0109] Non-limiting examples of the current collector used in the negative electrode include foil made of copper, gold, nickel, copper alloy, or a combination thereof. The current collector may also be laminated with a substrate made of any of the above materials.

[0110] The negative electrode may also contain conductive materials and binders commonly used in the art.

[0111] Meanwhile, the rolling apparatus 100 for manufacturing an electrode according to an embodiment of the present invention includes a guide unit 140 that guides the movement of the electrode substrate 10. The guide unit 140 may be, for example, a transfer roller. The guide unit 140 may adjust the skew of the electrode substrate 10 and adjust the tension of the electrode substrate 10. Finally, the electrode substrate 10 is rewinded by an electrode rewinder 150.

[0112] The electrodes manufactured using the method for controlling a rolling mill for manufacturing an electrode according to the present embodiment are included in secondary batteries, and a plurality of such secondary batteries can be combined to form a battery module. The battery module can be mounted together with various control and protection systems, such as a Battery Management System (BMS) and a cooling system, to form a battery pack.

[0113] The secondary battery, the battery module, or the battery pack may be applied to various devices, specifically, but not limited to, transportation means such as electric bicycles, electric cars, and hybrid vehicles, and may be applied to various devices that can use secondary batteries.

[0114] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0115] 10: Electrode base material 11: Plain area 12: Holding part 100: Rolling equipment for electrode manufacturing 110: Rolling section 120: Plain part extension part 120a: pressure section 130: Monitoring unit 130a: Processor 140: Guide section 150: Electrode rewinder

Claims

1. A rolling device for manufacturing electrodes, a rolling section that rolls the electrode base material as the electrode base material passes through; a non-coating portion stretching section that additionally stretches the non-coating portion of the electrode substrate that has passed through the rolling section, a rolling mill for manufacturing an electrode, wherein the uncoated portion extension section is configured so that a relative position of the uncoated portion extension section with respect to the electrode base material is adjusted according to a state of the uncoated portion of the electrode base material.

2. a driving unit for adjusting the position of the non-coating portion extending unit, 2. The rolling apparatus for manufacturing an electrode according to claim 1, wherein the position of the non-coating portion extension portion is adjusted by maintaining the position, moving forward toward the electrode substrate, or moving backward from the electrode substrate in the opposite direction.

3. The electrode substrate further includes a monitoring unit configured to monitor the electrode substrate and determine a state of an uncoated portion of the electrode substrate, When the non-coating portion of the electrode substrate is in a normal state, the non-coating portion extension portion maintains its position. When the uncoated portion of the electrode substrate is in a predetermined first abnormal state, the uncoated portion extension portion advances toward the electrode substrate, 3. The rolling apparatus for manufacturing an electrode according to claim 2, wherein when the uncoated portion of the electrode base material is in a predetermined second abnormal state, the uncoated portion extension portion moves backward from the electrode base material.

4. the first abnormal state is a state in which a valley or a ridge of the undulation of the uncoated portion is generated in the longitudinal direction of the electrode base material, 4. The rolling mill for manufacturing an electrode according to claim 3, wherein the second abnormal state is a state in which a valley or a ridge of the undulations of the uncoated portion occurs in the width direction of the electrode base material.

5. When an angle between a direction of a valley or a ridge of the undulation of the uncoated portion and a traveling direction of the electrode substrate is equal to or greater than 0 degrees and less than 45 degrees, the uncoated portion is determined to be in the first abnormal state; When the angle between the direction of the valley or ridge of the undulation of the uncoated portion and the traveling direction of the electrode substrate is more than 45 degrees and not more than 90 degrees, the uncoated portion is determined to be in the second abnormal state, 4. The rolling apparatus for manufacturing an electrode according to claim 3, wherein when an angle between a direction of a valley or a ridge of the undulations of the uncoated portion and a traveling direction of the electrode base material is 45 degrees, the uncoated portion is determined to be in either the first abnormal state or the second abnormal state.

6. When the uncoated portion of the electrode substrate is in the first abnormal state, the uncoated portion extension portion advances toward the electrode substrate by a first predetermined distance, 4. The rolling mill for manufacturing an electrode according to claim 3, wherein the advancement of the uncoated portion extension portion by the first predetermined value is repeated until the uncoated portion of the electrode base material is determined to be in a normal state.

7. When the uncoated portion of the electrode substrate is in the second abnormal state, the uncoated portion extension portion moves backward from the electrode substrate by a second predetermined value, 4. The rolling mill for manufacturing an electrode according to claim 3, wherein the uncoated portion extending portion is repeatedly moved backward by the second predetermined value until the uncoated portion of the electrode base material is determined to be in a normal state.

8. 4. The rolling apparatus for manufacturing an electrode according to claim 3, wherein the monitoring unit is located downstream of the uncoated portion extending section and monitors the state of the uncoated portion of the electrode substrate that has passed through the uncoated portion extending section, thereby adjusting the position of the uncoated portion extending section.

9. 4. The rolling apparatus for manufacturing an electrode according to claim 3, wherein the monitoring unit is located between a rear section of the rolling section and a front section of the uncoated portion extension section, and monitors the state of the uncoated portion of the electrode base material that has passed through the rolling section, thereby adjusting the position of the uncoated portion extension section.

10. the rolling unit is a pair of rolling rollers that rotate in opposite directions around a rotation axis, the non-coating portion stretching unit is a non-coating portion pressing roller including a pressing unit, 3. The rolling device for manufacturing an electrode according to claim 2, wherein the pressure section is provided at a position corresponding to the uncoated portion of the electrode base material and has a structure protruding from the outer peripheral surface of the uncoated portion pressure roller.

11. The rolling apparatus for manufacturing an electrode according to claim 10, wherein the driving unit is an actuator connected to the non-coating portion pressure roller.

12. The rolling apparatus for manufacturing an electrode according to claim 1 , further comprising a guide portion for guiding the movement of the electrode base material.

13. The rolling apparatus for manufacturing an electrode according to claim 1, further comprising an electrode rewinder for winding and recovering the electrode base material.

14. A rolling method for manufacturing an electrode, comprising: rolling the electrode substrate in a rolling section; further stretching the uncoated portion of the rolled electrode substrate in an uncoated portion stretching section; and monitoring the electrode substrate with a monitoring unit to determine a state of the uncoated portion of the electrode substrate; The rolling method for manufacturing an electrode further comprises adjusting a relative position of the uncoated portion extension portion with respect to the electrode substrate when the uncoated portion of the electrode substrate is in an abnormal state.

15. The rolling method for manufacturing an electrode according to claim 14, wherein the uncoated portion extension portion maintains its position when the uncoated portion of the electrode substrate is in a normal state.

16. The step of adjusting the relative position of the non-coating portion extension portion includes: When the non-coating portion of the electrode substrate is in a predetermined first abnormal state, the non-coating portion extension portion advances toward the electrode substrate; and and when the uncoated portion of the electrode substrate is in a predetermined second abnormal state, the uncoated portion extension portion moves backward from the electrode substrate side.

17. the first abnormal state is a state in which a valley or a ridge of the undulation of the uncoated portion is generated in the longitudinal direction of the electrode base material, The rolling method for manufacturing an electrode according to claim 16, wherein the second abnormal state is a state in which a valley or a ridge of the undulations of the uncoated portion occurs in the width direction of the electrode base material.

18. When an angle between a direction of a valley or a ridge of the undulation of the uncoated portion and a traveling direction of the electrode substrate is equal to or greater than 0 degrees and less than 45 degrees, the uncoated portion is determined to be in the first abnormal state; When the angle between the direction of the valley or ridge of the undulation of the uncoated portion and the traveling direction of the electrode substrate is more than 45 degrees and not more than 90 degrees, the uncoated portion is determined to be in the second abnormal state, 17. The rolling method for manufacturing an electrode according to claim 16, wherein when an angle between a direction of a valley or a ridge of the undulations of the uncoated portion and a traveling direction of the electrode base material is 45 degrees, the uncoated portion is determined to be in either the first abnormal state or the second abnormal state.

19. When the uncoated portion of the electrode substrate is in the first abnormal state, the uncoated portion extension portion advances toward the electrode substrate by a first predetermined distance, The rolling method for manufacturing an electrode according to claim 16, wherein the advancement of the uncoated portion extension portion by the first predetermined value is repeatedly performed until the uncoated portion of the electrode base material is determined to be in a normal state.

20. When the uncoated portion of the electrode substrate is in the second abnormal state, the uncoated portion extension portion moves backward from the electrode substrate by a second predetermined value, The rolling method for manufacturing an electrode according to claim 16, wherein the uncoated portion extension portion is repeatedly moved backward by the second predetermined distance until the uncoated portion of the electrode base material is determined to be in a normal state.

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