KR-20260063427-A - MANUFACTURING METHOD FOR LITHIUM SECONDARY BATTERY ELECTRODE, LITHIUM SECONDARY BATTERY ELECTRODE AND LITHIUM SECONDARY BATTERY INCLUDING THE SAME

Abstract

The present disclosure relates to a method for manufacturing an electrode for a lithium secondary battery, an electrode for a lithium secondary battery, and a lithium secondary battery including the same. A method for manufacturing an electrode for a lithium secondary battery according to one embodiment may include: a preparation step of forming an electrode active material layer on at least one surface of an electrode current collector; a forming step of forming a plurality of grooves in the electrode active material layer; and a rolling step of rolling the electrode active material layer in which a plurality of grooves are formed in the forming step.

Inventors

• 유경화
• 강병찬
• 임형주
• 진보경
• 허균

Assignees

• 에스케이온 주식회사

Dates

Publication Date

20260507

Application Date

20241030

Claims (18)

1. A preparation step of forming an electrode active material layer on at least one surface of an electrode current collector; A forming step of forming a plurality of grooves in the electrode active material layer; and A method for manufacturing an electrode for a lithium secondary battery, comprising: a rolling step of rolling an electrode active material layer having a plurality of grooves formed in the above forming step.
2. In Article 1, A method for manufacturing an electrode for a lithium secondary battery in which the above electrode is a negative electrode.
3. In claim 1, the forming step A method for manufacturing an electrode for a lithium secondary battery, wherein a plurality of grooves are formed such that the pitch between the plurality of grooves is independently 50 μm or more and 200 μm or less.
4. In claim 1, the forming step A method for manufacturing an electrode for a lithium secondary battery, wherein a plurality of grooves are formed such that the depth of each of the plurality of grooves is independently 10 μm or more and 250 μm or less.
5. In claim 1, the forming step A method for manufacturing an electrode for a lithium secondary battery, wherein a plurality of grooves are formed such that the width of each of the plurality of grooves is independently 10 μm or more and 200 μm or less.
6. In claim 1, the forming step A method for manufacturing an electrode for a lithium secondary battery, wherein the plurality of grooves are formed such that the shape observed in the cross-section in the thickness direction of the electrode active material layer is each independently selected from the group consisting of at least a part of a circle, at least a part of a square, at least a part of a triangle, and at least a part of a trapezoid.
7. In Paragraph 6, A method for manufacturing an electrode for a lithium secondary battery in which the plurality of grooves are formed with the same shape.
8. In claim 1, the rolling step A method for manufacturing an electrode for a lithium secondary battery, wherein the electrode active material layer is rolled such that the first thickness deviation defined by the following relationship 1 is 4.5% or less. [Relationship 1] First thickness deviation (%) = In the above relationship 1, T h is the maximum thickness of the electrode after the rolling step is performed, and T a is the average thickness of the electrode in the preparation step.
9. Electrode current collector; and The electrode active material layer formed on at least one surface of the electrode current collector; comprising The electrode active material layer comprises a plurality of grooves and a corresponding closure adjacent to each of the plurality of grooves, for an electrode for a lithium secondary battery.
10. In Article 9, The above electrode is a negative electrode for a lithium secondary battery.
11. In claim 9, the plurality of grooves are An electrode for a lithium secondary battery, wherein the pitch between the grooves is independently 50 μm or more and 200 μm or less.
12. In claim 9, the plurality of grooves are An electrode for a lithium secondary battery, wherein the depth of each groove is independently 10 μm or more and 250 μm or less.
13. In claim 9, the plurality of grooves are Electrode for a lithium secondary battery, wherein the width of each groove is independently 10 μm or more and 200 μm or less.
14. In claim 9, the plurality of grooves are An electrode for a lithium secondary battery comprising, wherein the shape observed in the cross-section in the thickness direction of the electrode active material layer is independently selected from the group consisting of at least a part of a circle, at least a part of a square, at least a part of a triangle, and at least a part of a trapezoid.
15. In Paragraph 14, The above plurality of grooves are electrodes for a lithium secondary battery having the same shape as each other.
16. In claim 9, the electrode is An electrode for a lithium secondary battery having a second thickness deviation of 4.5% or less, defined by the following relationship 2. [Relationship 2] Second thickness deviation (%) = In the above equation 2, L4 is the average thickness of the electrode and L5 is the maximum thickness of the electrode.
17. In Article 9, The above-mentioned closure is an electrode for a lithium secondary battery that seals a corresponding groove.
18. A lithium secondary battery comprising an electrode manufactured according to the manufacturing method of any one of claims 1 to 8 or an electrode according to any one of claims 9 to 17.

Description

Manufacturing method for lithium secondary battery electrode, lithium secondary battery electrode and lithium secondary battery including the same The present disclosure relates to a method for manufacturing an electrode for a lithium secondary battery, an electrode for a lithium secondary battery, and a lithium secondary battery including the same. More specifically, the present disclosure relates to a method for manufacturing an electrode for a lithium secondary battery, an electrode for a lithium secondary battery, and a lithium secondary battery including the same, wherein lifespan characteristics are not degraded even during rapid charging. As faster charging speeds can reduce the time required to prepare lithium-ion batteries for use after discharge, research on rapid-charging lithium-ion batteries has recently been attracting attention. However, in the case of conventional lithium secondary batteries, when rapidly charging at a high C-rate, lithium dendrites may form on the surface of the negative electrode due to negative electrode resistance, which can cause problems such as a decrease in battery capacity as the charge and discharge cycles progress. Therefore, there is a need to develop lithium secondary batteries that do not experience degradation in lifespan characteristics even during rapid charging. FIG. 1 is a flowchart illustrating a method for manufacturing an electrode for a lithium secondary battery according to one embodiment of the present disclosure. FIG. 2 is a diagram illustrating a method for manufacturing an electrode for a lithium secondary battery according to one embodiment of the present disclosure, wherein a plurality of grooves are formed in an electrode active material layer using a pattern roller during the forming step. FIG. 3 is a diagram showing the MD direction cross-section of the thickness direction cross-section of an electrode in which a plurality of grooves are formed in the electrode active material layer according to one embodiment of the above-described formation step. Figure 4 is a diagram showing the MD direction cross-section of the thickness direction cross-section of an electrode in which a plurality of grooves are formed in the electrode active material layer according to another embodiment of the above-described formation step. FIG. 5 is a diagram showing the MD direction cross-section of the thickness direction cross-section of an electrode in which a plurality of grooves are formed in the electrode active material layer according to another embodiment of the above-described formation step. FIG. 6 is a diagram showing the MD direction cross-section of the thickness direction cross-section of an electrode in which a plurality of grooves are formed in the electrode active material layer according to another embodiment of the above-described formation step. FIG. 7 is a drawing showing a cross-section in the MD direction of the thickness direction cross-section of an electrode for a lithium secondary battery according to one embodiment of the present disclosure. FIG. 8 is a drawing showing a cross-section in the MD direction of the thickness direction cross-section of an electrode for a lithium secondary battery according to another embodiment of the present disclosure. FIG. 9 is a drawing showing a cross-section in the MD direction of the thickness direction cross-section of an electrode for a lithium secondary battery according to another embodiment of the present disclosure. FIG. 10 is a drawing showing a cross-section in the MD direction of the thickness direction cross-section of an electrode for a lithium secondary battery according to another embodiment of the present disclosure. FIG. 11 is an SEM image of the surface of an electrode having a plurality of grooves formed in an active material layer according to one embodiment of the present disclosure. FIG. 12 is an SEM image of the surface of an electrode after rolling an electrode having a plurality of grooves formed in an active material layer according to one embodiment of the present disclosure. FIG. 13 is an XRM image of a cross-section in the thickness direction of an electrode having a plurality of grooves formed in an active material layer according to one embodiment of the present disclosure. FIG. 14 is an XRM image of a cross-section in the thickness direction of an electrode after rolling an electrode having a plurality of grooves formed in an active material layer according to one embodiment of the present disclosure. FIG. 15 is a graph showing the capacity retention rate of a battery including the negative electrodes of Example 2, Comparative Example 2, and Comparative Example 8. FIG. 16 is a graph showing the DC-IR values of a battery including the negative electrodes of Example 2, Comparative Example 2, and Comparative Example 8. Since the embodiments described in this specification may be modified in various different forms, the technology according to one embodiment is not limited to t