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EP-4478036-B1 - ELECTRODE SHEET DEFECT INSPECTION DEVICE

EP4478036B1EP 4478036 B1EP4478036 B1EP 4478036B1EP-4478036-B1

Inventors

  • LEE, JONG HWA
  • CHOI, Ee Beom

Dates

Publication Date
20260506
Application Date
20231212

Claims (15)

  1. An electrode sheet (10) defect inspection device comprising: a vision inspection part (110, 120) provided to inspect defects in each tab part (15, 18) during a traveling process of an electrode sheet (10) on which a plurality of tab parts (15) is formed; a marking part (130) printing a defective mark on the tab part (15, 18) determined to be defective, based on inspection information of the vision inspection part (110, 120); a tab guide part (200, 300') disposed to pass the tab part (15, 18) of the electrode sheet (10) passing through the marking part (130), having an opening (35, 45, 225) for exposing a partial region of the tab part (15, 18) during traveling to the outside, and provided so that a partial region surrounding the opening (35, 45, 225) is transparent; and a mark inspection part (70, 140) provided to inspect the defective mark indicated on the tab part (15, 18) exposed to the outside through the opening (35, 45, 225) of the tab guide part (200, 300').
  2. The electrode sheet (10) defect inspection device according to claim 1, wherein the tab guide part (200, 300') comprises: an upper guide member (30, 220) disposed at the upper portion of the tab part (15, 18) of the electrode sheet (10) during traveling, and having a first main body (211, 221) having a first opening (225) for exposing the tab part (15, 18) and an upper transparent member (229) provided to cover a partial region of the first opening (225), and a lower guide member disposed at the lower portion of the tab part (15, 18) of the electrode sheet (10) during traveling, and positioned to be apart at a predetermined interval from the upper guide member (30, 220).
  3. The electrode sheet (10) defect inspection device according to claim 2, wherein the tab guide part (200, 300') is disposed so that the tab part (15, 18) of the electrode sheet (10) during traveling passes through the interval between the upper guide member (30, 220) and the lower guide member.
  4. The electrode sheet (10) defect inspection device according to claim 2, wherein the upper guide member (30, 220) has a first guide surface (222) where the first main body (211, 221) faces the upper surface of the tab part (15, 18), and the upper transparent member (229) is provided so that one surface is positioned on the same plane as the first guide surface (222).
  5. The electrode sheet (10) defect inspection device according to claim 4, wherein the upper guide member (30, 220) is provided such that the first guide surface (222) comprises a non-transparent region through which light does not transmit.
  6. The electrode sheet (10) defect inspection device according to claim 4, wherein the upper guide member (30, 220) is provided so that a mounting surface (226, 236), on which the upper transparent member (229) is mounted, is orthogonal to the first guide surface (222).
  7. The electrode sheet (10) defect inspection device according to claim 5, wherein in the upper guide member (30, 220), the first main body (211, 221) and the upper transparent member (229) are formed of different materials.
  8. The electrode sheet (10) defect inspection device according to claim 2, wherein the upper transparent member (229) is formed of a glass material.
  9. The electrode sheet (10) defect inspection device according to claim 2, wherein the mark inspection part (70, 140) is provided to inspect the defective mark indicated on the tab part (15, 18) exposed through the first opening (225) of the upper guide member (30, 220).
  10. The electrode sheet (10) defect inspection device according to claim 2, wherein the lower guide member has a second main body (231) having a second opening (235, 235') for exposing the tab part (15, 18), and a lower transparent member provided to cover a partial region of the second opening (235, 235').
  11. The electrode sheet (10) defect inspection device according to claim 10, wherein the lower guide member has a second guide surface (222, 232, 232') where the second main body (231) faces the lower surface of the tab part (15, 18), and the lower transparent member is provided so that one surface is positioned on the same plane as the second guide surface (222, 232, 232').
  12. The electrode sheet (10) defect inspection device according to claim 11, wherein the lower guide member is provided so that the second guide surface (222, 232, 232') comprises a non-transparent region through which light does not transmit.
  13. The electrode sheet (10) defect inspection device according to claim 11, wherein the lower guide member is provided so that a mounting surface (226, 236), on which the lower transparent member is mounted, is orthogonal to the second guide surface (222, 232, 232').
  14. The electrode sheet (10) defect inspection device according to claim 10, wherein in the lower guide member, the second main body (231) and the lower transparent member are formed of different materials.
  15. The electrode sheet (10) defect inspection device according to claim 10, wherein the lower transparent member is formed of a glass material.

Description

Technical Field The present invention relates to an electrode sheet defect inspection device, and relates to an electrode sheet defect inspection device capable of preventing shadows from occurring upon inspecting defective marks by forming a partial region of a tab guide part with a transparent material. This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0174614 dated December 14, 2022. Background Art The types of devices that use secondary batteries as an energy source increase. Particularly, lithium secondary batteries are also used in a small-sized battery cell field used in mobile devices or small electronic products, and a medium and large-sized battery pack field used as an energy source for electric vehicles or power storage systems, and the like that require high output and high voltage, due to advantages such as high energy density and high charging voltage. The lithium secondary battery is manufactured by housing an electrode assembly and an electrolyte in a battery case, and sealing them. The electrode assembly is formed by laminating a positive electrode and a negative electrode with a separator interposed therebetween. The secondary battery manufacturing process comprises an electrode process, an assembly process, and an activation process, where the electrode process is a process of making a positive electrode and a negative electrode. Figure 1 is an electrode process flowchart of a secondary battery. As shown in Figure 1, the electrode process may comprise a mixing process (S1), a coating process (S2), a rolling process (S3), a slitting process (S4), and a notching process (S5). The mixing process (S1) is a process of measuring and mixing various raw materials necessary to make a negative electrode and a positive electrode, where a positive electrode slurry or a negative electrode slurry, in which various raw materials are mixed in the mixing process (S1), is produced. The coating process (S2) is a process of coating the positive electrode or negative electrode slurry on an electrode sheet (10) (see Figure 2, for example, copper or aluminum) through a coating device. The electrode sheet (10) coated with the positive electrode or negative electrode slurry through the coating process (S2) is transferred to the rolling process (S3). The rolling process (S3) is a process of rolling the slurry coated on the electrode sheet (10) while passing the electrode sheet (10) between two rolling rolls (not shown). In the slurry on the electrode sheet (10), its density increases and its volume decreases by the rolling process (S3). Figure 2 is a schematic diagram showing an arrangement state of a tab guide (20) with respect to an electrode sheet (10), Figure 3 is a perspective diagram schematically showing a tab guide (20) according to a conventional art, and Figure 4 is a diagram in a state cut along the line X-X of Figure 2, which shows an arrangement state of a mark inspection part (70) and a tab guide (20). After the rolling process (S3), the electrode sheet (10) is transferred to a cutting process (S4, S5). The cutting process (S4, S5) comprises a slitting process (S4) and a notching process (S5). Here, the slitting process (S4) is a process of cutting the electrode sheet (10) into a plurality of electrodes. Then, the notching process (S5) is a process for forming a tab part (15) using a laser or the like on a plain part (12) on which the slurry is not applied on an electrode base material (10a). In this instance, in the notching process (S5), which is the last step of the electrode process, a defect inspection of the tab part (15) for the electrode sheet (10) after notching is performed. After the notching process (S5), the tab part (15) of the electrode sheet (10) is inspected for defects based on photographic information obtained by photographing the tab part (15) of the electrode sheet (10) using a vision camera. In this instance, lifting or sagging of the tab part (15), and the like is checked through the defect inspection of the tab part (15). Afterwards, based on the vision inspection information, a defective mark is indicated on the tab part (15) that is determined to be defective. For example, the defective mark may be printed on the tab part (15) where a defect exists in the electrode sheet (10). Afterwards, it is inspected whether the defective mark has been properly printed on the tab part (15) of the electrode sheet (10). Upon inspecting defective marks, the tab guide (20) is used. Referring to Figures 2 and 3, the tab guide (20) is disposed to pass the edge of the electrode sheet (10) in the width direction (W), that is, the plain part (12) on which the tab part (15) is formed. Referring to Figures 3 and 4, the conventional tab guide (20) comprises an upper guide member (30) and a lower guide member (40). The upper guide member (30) and the lower guide member (40) are disposed above and below the tab part (15) of the electrode sheet (10), respec