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JP-2026076292-A - Electrode rolling machine

JP2026076292AJP 2026076292 AJP2026076292 AJP 2026076292AJP-2026076292-A

Abstract

[Problem] To provide an electrode rolling apparatus in which both the first and second rolling rollers can be used for rolling plain sections. [Solution] The present invention relates to an electrode rolling apparatus that applies pressure to the plain portion of an electrode. [Selection Diagram] Figure 3

Inventors

  • ヨン・デ・キム

Assignees

  • エルジー エナジー ソリューション リミテッド

Dates

Publication Date
20260511
Application Date
20260206
Priority Date
20221005

Claims (17)

  1. An electrode rolling apparatus that applies pressure to the uncoated portion of an electrode, comprising a maintenance portion coated with an electrode active material and a plain portion not coated with an electrode active material, wherein the plain portion includes an insulating coated portion and a non-insulating coated portion. The electrode rolling apparatus includes a first rolling roller and a second rolling roller, The first rolling roller includes a first central part and a first end located at one end of the first central part in the longitudinal direction. The second rolling roller includes a second central part and a second end located at one end of the second central part in the longitudinal direction. The other end cross-section of the first central part and the other end cross-section of the second central part are in contact with each other. The first-1 outer diameter of the first central part connected to the first end is different from the first-2 outer diameter of the first central part that is in contact with the other end cross section of the second central part. The second-1 outer diameter of the second central part connected to the second end is different from the second-2 outer diameter of the second central part that is in contact with the other end cross section of the first central part. The outer diameters of the first and second 2 are the same. An electrode rolling apparatus in which the first end or the second end is adjacent to the boundary between the insulating coated portion and the non-insulating coated portion.
  2. The electrode rolling apparatus according to claim 1, wherein the outer diameter of the first-first is smaller than the outer diameter of the first-second, and the outer diameter of the second-first is smaller than the outer diameter of the second-second, or the outer diameter of the first-first is larger than the outer diameter of the first-second, and the outer diameter of the second-first is larger than the outer diameter of the second-second.
  3. The electrode rolling apparatus according to claim 2, wherein the lengths of the first central part and the second central part are the same or different from each other.
  4. The lengths of the first central part and the second central part are the same. The electrode rolling apparatus according to claim 3, wherein the 1-1 outer diameter and the 2-1 outer diameter are the same or different from each other.
  5. The lengths of the first central part and the second central part are different from each other. The electrode rolling apparatus according to claim 3, wherein the 1-1 outer diameter and the 2-1 outer diameter are the same or different from each other.
  6. The electrode rolling apparatus according to claim 3, wherein the ratio of the lengths of the first central part and the second central part is 3:5 to 5:3.
  7. The outer diameter of the first-2 is 0.8 to 0.99 times or 1.01 to 1.2 times the outer diameter of the first-1. The electrode rolling apparatus according to claim 1, wherein the outer diameter of the second-second part is 0.8 to 0.99 times or 1.01 to 1.2 times the outer diameter of the second-first part.
  8. The first end has a tapered shape in which the outer diameter gradually decreases from the first center to the rear end. The electrode rolling apparatus according to claim 1, wherein the second end has a tapered shape in which the outer diameter gradually decreases from the second center to the rear end.
  9. The electrode rolling apparatus according to claim 8, wherein the tapered surfaces of the first and second ends include a curved tapered surface and a linear tapered surface extending from the curved tapered surface.
  10. The electrode rolling apparatus according to claim 8, wherein the taper angles of the first end and the second end are the same or different from each other.
  11. The electrode rolling apparatus according to claim 10, wherein the taper angles of the first and second ends are 20 to 30 degrees.
  12. The materials of the first rolling roller and the second rolling roller are either the same or different. The electrode rolling apparatus according to claim 1, wherein the material is a metal or a polymer.
  13. The electrode rolling apparatus according to claim 1, wherein the insulating coating portion includes one or more materials selected from the group consisting of insulating polymer materials and insulating ceramic materials.
  14. The material of the first rolling roller or the second rolling roller is metal. The electrode rolling apparatus according to claim 1, wherein the insulating coating portion includes an insulating polymer material.
  15. The material of the first rolling roller or the second rolling roller is a polymer. The electrode rolling apparatus according to claim 1, wherein the insulating coating portion includes an insulating ceramic material.
  16. The electrode rolling apparatus according to any one of claims 1 to 15, wherein at least one of the outer circumferential surfaces of the first central part, the first end, the second central part, and the second end has grooves and protrusions alternately formed on the plain portion, parallel to the direction from the maintenance portion to the rear end of the plain portion.
  17. The electrode rolling apparatus according to claim 16, wherein the groove and protrusion have a cross-sectional shape similar to a triangle or a semicircle.

Description

This application claims priority under Korean Patent Application No. 10-2022-0126836 dated October 5, 2022, and incorporates all the contents disclosed in the said Korean Patent Application as part of this Specification. This invention relates to an electrode rolling apparatus, and more specifically, to an electrode rolling apparatus that applies pressure to the plain portion of an electrode. Rechargeable batteries are not only used as an energy source for mobile devices, but recently their use as a power source for electric vehicles (EVs) and hybrid electric vehicles (HEVs) has also become a reality, and their applications are expanding to include auxiliary power sources in the context of grid infrastructure. The manufacturing process for such secondary batteries is broadly divided into three stages: the electrode process, the assembly process, and the chemical conversion process. The electrode process is further divided into the active material mixing process, the electrode coating process, the rolling process, the slitting process, the winding process, and so on. Of these steps, the rolling process involves reducing the thickness of the electrode sheet after the electrode active material coating process is complete, increasing its capacity density, and improving the adhesion and bonding between the electrode current collector and the electrode active material. This process involves passing the electrode sheet between two high-temperature heated rolling rollers to compress it to the desired thickness and density. In this rolling process, the thickness of the electrode sheet is determined by the rolling gap between the two rolling rollers. This rolling gap is calculated by operating a drive unit that controls the vertical position of the rolling rollers, thereby compressing and rolling the electrode to the desired thickness. Generally, with one of the two rolling rollers fixed, the position of the remaining roller is adjusted by the drive unit, and the electrode is compressed and rolled based on the calculated rolling gap. However, when the electrode sheet is rolled by rolling rollers, almost no pressure is applied to the uncoated areas compared to the coated areas (the areas where the electrode active material is applied). This difference in stretching rates between the coated and uncoated areas causes undulation or wrinkles to occur in the uncoated areas. Such undulations and wrinkles cause meandering and serious dimensional defects in the winding process that follows the rolling process, ultimately hindering the quality of electrodes for secondary batteries. Therefore, an additional step is required to roll the plain areas after the electrode sheet has been rolled. Figure 1 is a cross-sectional view showing a conventional electrode rolling mill for rolling a plain portion. The conventional electrode rolling mill includes one rolling roll (10), which includes a central part (11), a first end (12), and a second end (13). Here, in the electrode rolling mill, the outer surface of the central part (11) extends from the first end (12) to the second end (13), and the first outer diameter (r1) of the central part (11) connected to the first end (12) is greater than the second outer diameter (r2) of the central part (11) connected to the second end (13). The plain portion (22) of the electrode (20) includes an insulating coated portion (23) and a non-insulating coated portion (24), and the first end (12) is located adjacent to the boundary between the insulating coated portion (23) and the non-insulating coated portion (24) of the electrode (20), and applies pressure to the insulating coated portion (23) and the non-insulating coated portion (24). Because the first outer diameter (r1) is larger than the second outer diameter (r2), even if there is a difference in thickness between the insulating coating portion (23) and the non-insulating coating portion (24), pressure is applied uniformly, reducing the deviation in the elongation rate. However, in the conventional electrode rolling apparatus described above, the plain portion (22) of the electrode (20) can only be rolled using the first end, which has a larger outer diameter, and the second end (13) cannot be used to roll the plain portion (22). Therefore, when the rolling roll (10) needs to be replaced due to wear at the first end (12), the second end (13) must also be discarded. This results in significant economic costs for rolling the plain portion (22), and efforts to improve this situation are necessary. Korean Published Patent No. 2019-0059210Korean Published Patent No. 2022-0067239 This is a cross-sectional view showing a conventional electrode rolling mill.This is a cross-sectional view of the electrode.This is a cross-sectional view showing an electrode rolling apparatus used for the plain portion of an electrode according to one embodiment of the present invention.This is a cross-sectional view showing an electrode rolling apparatus used for the plai