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EP-4742313-A1 - ELECTRODE AND RECHARGEABLE BATTERY INCLUDING THE SAME

EP4742313A1EP 4742313 A1EP4742313 A1EP 4742313A1EP-4742313-A1

Abstract

An electrode for a rechargeable battery according to an example embodiment includes a substrate, an active material layer formed on the substrate, a hole formed in the active material layer, and a first groove and a second groove formed on both sides of the hole and spaced apart from the hole.

Inventors

  • LEE, HOJUNG
  • KIM, YEONGAP
  • HONG, DAEHYUN
  • MIN, JUNGKI
  • JI, Hyeongmin

Assignees

  • SAMSUNG SDI CO., LTD.

Dates

Publication Date
20260513
Application Date
20251030

Claims (15)

  1. An electrode (700) for a rechargeable battery (110), the electrode (700) comprising: a substrate (70); an active material layer (71) formed on the substrate (70); a hole (S1) formed in the active material layer (71); and a first groove (S2) and a second groove (S3) formed on both sides of the hole (S1) and spaced apart from the hole (S1).
  2. The electrode (700) for the rechargeable battery (110) of claim 1, wherein a sum of the length of the first groove (S2) and a length of the second groove (S3) is in a range of about 10% to about 80% of a length of the active material layer (71) in a first direction.
  3. The electrode (700) for the rechargeable battery (110) of claim 1 or 2, wherein an interval between the first groove (S2) and the second groove (S3) is in a range of about 10% to about 80% of a length of the active material layer (71) in a first direction.
  4. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein the electrode (700) comprises a plurality of holes (S1) have an opening facing the surface of the active material layer (71), and the plurality of holes (S1) are arranged at regular intervals.
  5. The electrode (700) for the rechargeable battery (110) of claim 4, wherein the hole (S1) has a shape that narrows in width with increasing distance from the surface of the active material layer (71).
  6. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein a depth of the first groove (S2) and the second groove (S3) is substantially constant.
  7. The electrode (700) for the rechargeable battery (110) of claim 6, wherein a depth of the first groove (S2) and of the second groove (S3) is shallower than a depth of the hole (S1).
  8. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein a center of the hole (S1) and the horizontal line that bisects a width of the groove (15) are positioned on a same straight line.
  9. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein: the first groove (S2) and the second groove (S3) are inclined at an angle in a range of about -50 degrees to about 50 degrees with respect to a virtual center line passing between the first groove (S2) and the second groove (S3) and bisecting a length of the active material layer (71) in a first direction.
  10. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein: the hole (S1), the first groove (S2) and the second groove (S3) are substantially symmetrical with respect to a virtual center line passing between the first groove (S2) and the second groove (S3) and bisecting a length of a first direction of the active material layer (71).
  11. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein the first groove (S2) and the second groove (S3) comprise a curved line.
  12. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein: the width of the first groove (S2) and of the second groove (S3) is in a range of about 10µm to about 100µm, and an interval between adjacent first grooves (S2) and an interval between adjacent second grooves (S3) are in a range of about 70µm to about 300µm.
  13. The electrode (700) for the rechargeable battery (110) of any one of the preceding claims, wherein the diameter of the hole (S1) is in a range of about 10 µm to about 100 µm.
  14. A rechargeable battery (110) comprising: an electrode assembly (130) including a positive electrode (131), a negative electrode (132) overlapping the positive electrode (131), and a separator (133) between the positive electrode (131) and the negative electrode (132); a case (120) accommodating the electrode assembly (130); an electrolyte injected into the case (120); and a cap assembly (140) sealing the case (120); wherein at least one of the positive electrode (131) and the negative electrode (132) includes an active material layer (71) having a substrate (70), a first groove (S2) and a second groove (S3) formed on the substrate (70) and spaced apart from each other in a direction in which the electrolyte is injected, and a hole (S1) positioned between the first groove (S2) and the second groove (S3).
  15. The rechargeable battery (110) of claim 14, wherein a plurality of holes (S1) are placed at regular intervals on the active material layer (71).

Description

BACKGROUND OF THE DISCLOSURE (a) Field of the Disclosure The present disclosure relates to an electrode, and a rechargeable battery including the electrode. (b) Description of the Related Art As technology for portable devices develops, demand for rechargeable batteries as an energy source is increasing. A rechargeable battery, unlike a primary battery, may be repeatedly charged and discharged. Rechargeable batteries may be manufactured by overlapping a positive electrode, a separator, and a negative electrode, and then winding the positive electrode, the separator, and the negative electrode to form a cylindrical or jelly roll-shaped electrode assembly, or by separating the positive electrode, the separator, and the negative electrode into sheets and then laminating the sheets to form a laminated electrode assembly. In the rechargeable battery, the electrode assembly is inserted into the case, and an electrolyte is then injected. An impregnation amount of the electrolyte may vary depending on the state of edges and a center of the electrode assembly or an active material layer. A non-uniform electrolyte can lead to lithium (Li) precipitation, shortening the battery's lifespan and making rapid charging challenging. SUMMARY OF THE DISCLOSURE Examples of the present disclosure provide an electrode capable of reducing electrolyte non-uniformity at an edge and center of the electrode, and a rechargeable battery including the electrode. An electrode for a rechargeable battery according to an aspect includes a substrate, an active material layer formed on the substrate, a hole formed in the active material layer, and a first groove and a second groove formed on both sides of the hole and spaced apart from the hole. The sum of the length of the first groove and the length of the second groove may be in a range of about 10% to about 80% of the length in a first direction of the active material layer. An interval between the first groove and the second groove may be in a range of about 10% to about 80% of the length of the active material layer in the first direction. The holes may have an opening facing the surface of the active material layer, may be formed in multiples, and may be arranged at regular intervals. The holes may have a shape that narrows in width as the distance from the surface of the active material layer increases. The depth of the first groove and the second groove may be constant. The depth of the first groove and the second groove may be shallower than the depth of the hole. The center of the hole and a horizontal line that bisects the width of the groove may be positioned on one straight line. The first groove and the second groove may be inclined at an angle in a range of about -50 to about 50 degrees with respect to an imaginary or virtual center line passing between the first groove and the second groove and bisecting the length of the first direction of the active material layer. The hole, the first groove and the second groove may be symmetrical, or substantially symmetrical, with respect to the imaginary or virtual center line passing between the first groove and the second groove and bisecting the length of the first direction of the active material layer. The first groove and the second groove may include a curved line. The width of the first groove and the second groove may be in a range of about 10 µm to about 100 µm, and the interval between the adjacent first grooves and the interval between the adjacent second grooves may be in a range of about 70 µm to about 300 µm. The diameter of the hole may be in a range of about 10 µm to about 100 µm. A rechargeable battery according to another aspect includes an electrode assembly including a positive electrode, a negative electrode overlapping the positive electrode, a separator positioned between the positive electrode and the negative electrode, a case accommodating the electrode assembly, an electrolyte injected into the case, and a cap assembly sealing the case. At least one of the positive electrode and the negative electrode includes an active material layer having a substrate, the first groove and the second groove formed on the substrate and spaced apart from each other in a direction in which the electrolyte is injected, and a hole positioned between the first groove and the second groove. The sum of the length of the first groove and the length of the second groove may be in a range of about 10% to about 80% of the length of the active material layer in the direction in which the electrolyte is injected. The interval between the first groove and the second groove may be in a range of about 10% to about 80% of the length of the active material layer in the direction in which the electrolyte is injected. The holes may be formed in a plurality and may be placed at a given interval. The first groove and the second groove may be inclined at an angle in a range of about -50 degrees to about 50 degrees with respect to the imaginary or v