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CN-122025528-A - Electrode and secondary battery

CN122025528ACN 122025528 ACN122025528 ACN 122025528ACN-122025528-A

Abstract

The present disclosure relates to an electrode and a secondary battery, and a technical problem to be solved is to provide an electrode that prevents a substrate from being damaged by a tab. To this end, the present disclosure provides an electrode including a substrate, an active material layer provided on a portion of the substrate, and a tab in contact with the substrate, wherein at least a portion of the tab is located on the active material layer.

Inventors

  • JIN GUICAI
  • DING YUANYI

Assignees

  • 三星SDI株式会社

Dates

Publication Date
20260512
Application Date
20251110
Priority Date
20241112

Claims (14)

  1. 1. An electrode, comprising: A substrate; An active material layer provided on a part of the substrate, and And a tab in contact with the substrate, wherein at least a portion of the tab is located on the active material layer.
  2. 2. The electrode of claim 1, wherein the tab is formed such that a first side of the tab is in contact with the substrate and a second side of the tab extends away from the substrate, and The tab includes a first edge connecting the first side and the second side.
  3. 3. The electrode of claim 2, wherein at least a portion of the first edge is located on the active material layer.
  4. 4. The electrode according to claim 3, wherein the tab further comprises a second edge located at a position on the tab farthest from the first edge in a width direction of the tab, and Wherein at least a portion of the second edge is located on the active material layer.
  5. 5. The electrode of claim 2, wherein the tab is positioned such that at least a portion of the first edge is in contact with the active material layer.
  6. 6. The electrode of claim 1, wherein a length of a portion of the tab on the substrate is the same as or less than a length of the substrate.
  7. 7. The electrode of any one of claims 1 to 5, wherein the electrode further comprises: a coating portion on which the active material layer is provided on the substrate, and An uncoated portion on which the active material layer is not provided on the substrate, wherein the tab is formed to have a width wider than the uncoated portion.
  8. 8. The electrode according to any one of claims 1 to 5, wherein the wiring tab is formed to have a thickness less than or equal to a thickness of the active material layer, and The electrode further includes a reinforcing layer attached to the tab.
  9. 9. The electrode according to any one of claims 1 to 5, wherein the tab has a thickness exceeding a thickness of the active material layer.
  10. 10. The electrode according to any one of claims 1 to 5, further comprising an insulating tape comprising an insulating material covering the tab.
  11. 11. The electrode of any one of claims 1 to 5, wherein the tab is electrically connected to the substrate, and wherein the tab is in contact with the substrate via a solder portion.
  12. 12. The electrode of claim 11, wherein the weld portion comprises a first weld portion and a second weld portion positioned spaced apart from one another.
  13. 13. A secondary battery, comprising: an electrode assembly formed by winding an electrode and a separator, and A case accommodating the electrode assembly, Wherein the electrode is an electrode according to any one of claims 1 to 12.
  14. 14. The secondary battery according to claim 13, wherein the tab has a thickness of 100 μm or less.

Description

Electrode and secondary battery Cross Reference to Related Applications The present application claims priority and equity from korean patent application No. 10-2024-0159843 filed in the korean intellectual property office on day 11 and 12 of 2024, the entire disclosure of which is incorporated herein by reference. Technical Field The present disclosure relates to an electrode and a secondary battery capable of preventing cracks from occurring in a substrate. Background Unlike a primary battery that cannot be recharged, a secondary battery is a battery that can be charged and discharged. Low-capacity secondary batteries are used for small portable electronic devices such as smart phones, function phones, notebook computers, digital cameras, and video cameras, while high-capacity secondary batteries are widely used as power sources for motors in hybrid vehicles, electric vehicles, and the like, and as storage batteries. These secondary batteries include an electrode assembly including an electrode (e.g., including a positive electrode and/or a negative electrode), a case accommodating the electrode assembly, an electrode terminal connected to the electrode assembly, and the like. The electrode includes a substrate and an active material layer formed on the substrate. The active material layer includes an active material. In addition, the electrode may include a tab attached to the substrate. An electrode assembly comprising such an electrode may be wound, for example, to form a electrode core (i.e., a plurality of electrodes stacked layer upon layer and wound together, resulting in a cylindrical wound structure). When the secondary battery is charged, the electrode may expand. In this case, the substrate may be deformed as the electrode is compressed by expansion. In particular, stress applied to the substrate may concentrate at a tab boundary, which is an area where the tab is attached in the substrate. Accordingly, the tab boundary may reach its local extension limit, and cracks may occur at the tab boundary. In recent years, as the demand for high-capacity secondary batteries increases, the substrate tends to become thinner. Accordingly, cracks are more likely to occur in the substrate. When a crack occurs in the electrode, the resistance of the secondary battery increases, heat is generated around the crack, and/or the capacity of the secondary battery decreases, which results in a decrease in the reliability of the secondary battery. The above information disclosed in the background of the present disclosure is only intended to enhance understanding of the background of the present disclosure and thus may include information that does not constitute a related art. Disclosure of Invention One embodiment of the present disclosure relates to an electrode and/or a secondary battery that mitigates the occurrence of cracks in a substrate. One embodiment of the present disclosure relates to an electrode and/or a secondary battery that relieves stress from being concentrated on a substrate by a tab. However, technical problems to be achieved by the present disclosure are not limited to the above-described problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. According to one embodiment of the present disclosure, to solve the above technical problems, an electrode includes a substrate, an active material layer provided on a portion of the substrate, and a tab in contact with the substrate, wherein at least a portion of the tab is located on the active material layer. According to one embodiment of the present disclosure, to solve the above technical problems, a secondary battery includes an electrode assembly formed by winding an electrode and a separator, and a case accommodating the electrode assembly, wherein the electrode includes a substrate, an active material layer provided on a portion of the substrate, and a tab in contact with the substrate, wherein at least a portion of the tab is positioned on the active material layer. Drawings The following drawings accompanying the present specification illustrate preferred embodiments of the present disclosure and, together with the detailed description of the present disclosure described below, serve to further understand the technical ideas of the present disclosure, and thus the present disclosure is not limited to what is described in these drawings, in which: fig. 1 is a sectional view schematically illustrating an example of a cylindrical secondary battery according to an embodiment of the present disclosure; FIG. 2 is a cross-sectional view illustrating an example of an electrode; fig. 3 is a cross-sectional view illustrating an example of an electrode assembly; FIG. 4 is a cross-sectional view illustrating an example of an electrode according to one embodiment of the present disclosure; FIG. 5 is a cross-sectional view illustrating an example of an electrode according to one embod