KR-20260066358-A - ELECTRODE AND LITHIUM SECONDARY BATTERY INCLUDING THE SAME

KR20260066358AKR 20260066358 AKR20260066358 AKR 20260066358AKR-20260066358-A

Abstract

An electrode for a lithium secondary battery according to one embodiment of the present invention comprises: an electrode current collector; and a multilayer active material layer on the electrode current collector, wherein the multilayer active material layer comprises a first active material layer, a second active material layer, and a third active material layer sequentially stacked on the electrode current collector, wherein the first active material layer comprises a first active material and the third active material layer comprises a second active material. The second active material layer comprises first regions comprising the first active material; and second regions comprising the second active material. The first regions and the second regions are alternately arranged along a first direction, the first regions extend parallel to each other in a second direction intersecting the first direction, and the second regions extend parallel to each other in the second direction. The porosity of the third active material layer is greater than that of the second active material layer, and the porosity of the second active material layer is greater than that of the first active material layer.

Inventors

박정주
남현
여정옥
박진석
이민호
정민영

Assignees

삼성에스디아이 주식회사

Dates

Publication Date: 20260512
Application Date: 20241104

Claims (20)

Electrode current collector; and It includes a multilayer active material layer on the electrode current collector, The above multilayer active material layer comprises a first active material layer, a second active material layer, and a third active material layer sequentially stacked on the electrode current collector, and The above first active material layer includes the first active material, The above third active material layer includes a second active material, The above second active material layer is: First regions comprising the first active material; and It includes second regions comprising the above-mentioned second active material, and The first regions and the second regions are arranged alternately along the first direction, and The first regions are extended parallel to each other in a second direction that intersects the first direction, and The above second regions extend parallel to each other in the above second direction, and The porosity of the third active material layer is greater than that of the second active material layer, and The porosity of the second active material layer is greater than that of the first active material layer. Electrode for lithium secondary battery.
In paragraph 1, Each of the above first active material layer, second active material layer, and third active material layer further comprises a binder and a conductive material, wherein The content of the conductive material in the second active material layer is 3 to 10 times greater than the content of the conductive material in the first active material layer or the third active material layer. Electrode for lithium secondary battery.
In paragraph 2, An electrode for a lithium secondary battery, wherein the content of the conductive material in the first active material layer and the third active material layer is 0.001 weight% to 0.5 weight%.
In paragraph 2, An electrode for a lithium secondary battery, wherein the content of the conductive material in the second active material layer is 1 weight% to 5 weight%.
In paragraph 2, The above conductive material comprises at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, acetylene black, ketjenblack, carbon fiber, carbon nanofiber, and carbon nanotube. Electrode for lithium secondary battery.
In paragraph 2, The above binder comprises at least one selected from the group consisting of rubber-based binders, acrylate-based binders, polyvinylidene fluoride-based binders, polyvinylpyrrolidone-based binders, acetate-based binders, polyvinyl alcohol-based binders, and cellulose-based binders. Electrode for lithium secondary battery.
In paragraph 1, The average particle size (D 50 ) of the first active material is smaller than the average particle size (D 50 ) of the second active material, and The average particle size (D 50 ) of the first active material is 2 μm to 30 μm, and The average particle size (D 50 ) of the second active material is 10 μm to 50 μm, Electrode for lithium secondary battery.
In paragraph 1, An electrode for a lithium secondary battery, wherein the first active material and the second active material are each independently represented by the following chemical formula 1: [Chemical Formula 1] Li x4 M 1 y M 2 z M 3 1-yz O 2- a In the above chemical formula 1, 0.5≤x4≤1.8, 0≤a≤0.05, 0<y≤1, 0≤z≤1, and 0≤y+z≤1, and M1 , M2 , and M3 each independently comprise one or more elements selected from metals such as Ni, Co, Mn, Al, B, Ba, Ca, Ce, Cr, Fe, Mo, Nb, Si, Sr, Mg, Ti, V, W, Zr, or La, and combinations thereof, and X includes one or more elements selected from F, S, P, or Cl.
In paragraph 1, An electrode for a lithium secondary battery, wherein the volume ratio of the first regions and the second regions is 1:9 to 9:1.
In paragraph 1, An electrode for a lithium secondary battery, wherein the thickness of the second active material layer is 30 to 70% with respect to the first active material layer or the third active material layer.
Electrode current collector; A first active material layer on the electrode current collector; and It includes a second active material layer on the first active material layer, The above first active material layer is: First regions comprising a first active material; and It includes second regions containing a second active material, and The first regions and the second regions are arranged alternately along the first direction, and The first regions are extended parallel to each other in a second direction that intersects the first direction, and The above second regions extend parallel to each other in the above second direction, and The second active material layer comprises the second active material, The second active material layer has a lower rolling density than the first active material layer. Electrode for lithium secondary battery.
In Paragraph 11, The porosity of the second active material layer is greater than that of the first active material layer. Electrode for lithium secondary battery.
In Paragraph 11, Each of the above first active material layer and second active material layer further comprises a binder and a conductive material, wherein The content of the conductive material in the first active material layer is 3 to 10 times greater than the content of the conductive material in the second active material layer. Electrode for lithium secondary battery.
In Paragraph 13, An electrode for a lithium secondary battery, wherein the content of the conductive material in the first active material layer is 1% to 5% by weight.
In Paragraph 13, The above conductive material comprises at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, acetylene black, ketjenblack, carbon fiber, carbon nanofiber, and carbon nanotube. The above binder comprises at least one selected from the group consisting of rubber-based binders, acrylate-based binders, polyvinylidene fluoride-based binders, polyvinylpyrrolidone-based binders, acetate-based binders, polyvinyl alcohol-based binders, and cellulose-based binders. Electrode for lithium secondary battery.
In Paragraph 11, The average particle size (D 50 ) of the first active material is smaller than the average particle size (D 50 ) of the second active material, and The average particle size (D 50 ) of the first active material is 2 μm to 30 μm, and The average particle size (D 50 ) of the second active material is 10 μm to 50 μm, Electrode for lithium secondary battery.
In Paragraph 11, An electrode for a lithium secondary battery, wherein the first active material and the second active material are each independently represented by the following chemical formula 1: [Chemical Formula 1] Li x4 M 1 y M 2 z M 3 1-yz O 2- a In the above chemical formula 1, 0.5≤x4≤1.8, 0≤a≤0.05, 0<y≤1, 0≤z≤1, and 0≤y+z≤1, and M1 , M2 , and M3 each independently comprise one or more elements selected from metals such as Ni, Co, Mn, Al, B, Ba, Ca, Ce, Cr, Fe, Mo, Nb, Si, Sr, Mg, Ti, V, W, Zr, or La, and combinations thereof, and X includes one or more elements selected from F, S, P, or Cl.
In Paragraph 11, An electrode for a lithium secondary battery, wherein the volume ratio of the first regions and the second regions is 1:9 to 9:1.
In Paragraph 11, An electrode for a lithium secondary battery, wherein the thickness of the first active material layer is 30 to 70% with respect to the second active material layer.
anode; cathode; A separator interposed between the anode and the cathode; and Includes electrolyte, but, A lithium secondary battery in which at least one of the anode and the cathode is an electrode according to any one of claims 1 to 19.

Description

Electrode and Lithium Secondary Battery Including the Same The present invention relates to an electrode and a lithium secondary battery including the same. Recently, accompanied by the rapid proliferation of battery-powered electronic devices such as mobile phones, laptop computers, and electric vehicles, the demand for high-energy-density, high-capacity rechargeable batteries is rapidly increasing. Accordingly, research and development to improve the performance of lithium-ion batteries is actively underway. A lithium secondary battery is a battery comprising a positive electrode and a negative electrode containing an active material capable of lithium ion intercalation and deintercalation, and an electrolyte, which produces electrical energy through oxidation and reduction reactions when lithium ions are intercalated or deintercalated from the positive and negative electrodes. FIG. 1 is a conceptual diagram briefly illustrating a lithium secondary battery according to embodiments of the present invention. FIGS. 2 to 5 are schematic diagrams illustrating a lithium secondary battery according to one embodiment, where FIG. 2 is a cylindrical type, FIG. 3 is a prismatic type, and FIGS. 4 and 5 are pouch-type battery shapes. FIG. 6 is a schematic diagram of an electrode for a lithium secondary battery according to one embodiment of the present invention. FIG. 7 is a cross-sectional view illustrating an electrode for a secondary battery according to embodiments of the present invention. FIG. 8 is an enlarged view for illustrating an electrode according to embodiments of the present invention. FIG. 9 is a schematic diagram of an electrode according to other embodiments of the present invention. FIG. 10 is a cross-sectional view illustrating an electrode according to other embodiments of the present invention. FIG. 11 is an enlarged view illustrating an electrode according to other embodiments of the present invention. FIG. 12a is a drawing for explaining a method for manufacturing an electrode according to one embodiment of the present invention. FIG. 12b is a drawing for explaining a method for manufacturing an electrode according to another embodiment of the present invention. In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of these embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Additionally, in the drawings, the thicknesses of the components are exaggerated for the effective description of the technical content. Throughout the specification, parts indicated by the same reference numeral represent the same components. The embodiments described herein will be described with reference to cross-sectional and/or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of the films and regions are exaggerated for effective description of the technical content. Accordingly, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific forms of the regions and are not intended to limit the scope of the invention. Although terms such as first, second, third, etc., have been used to describe various components in the various embodiments of this specification, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include their complementary embodiments. Unless otherwise specified in this specification, the singular form may also include the plural. Additionally, unless otherwise specified, "A or B" may mean "comprising A, comprising B, or comprising A and B." As used herein, "comprises" and/or "comprising" do not exclude the presence or addition of one or more other components to the mentioned components. In this specification, "combination of these" may mean a mixture of components, a laminate, a composite, a copolymer, an alloy, a blend, and a reaction product, etc. Unless otherwise defined in this specification, the particle size may be the average particle size. Additionally, the particle size refers to the average particle size ( D50 ), which represents the diameter of the particle whose cumulative volume in the particle size distribution is 50% by volume. The average particle size ( D50 ) may be measured by methods widely kn