CN-122000285-A - Positive electrode for lithium secondary battery and lithium secondary battery comprising same

Abstract

A positive electrode for a lithium secondary battery according to a specific embodiment of the present invention includes a positive electrode current collector and a positive electrode mixture layer on at least one side of the positive electrode current collector, wherein the positive electrode mixture layer includes a first positive electrode mixture layer on the positive electrode current collector and a second positive electrode mixture layer on the first positive electrode mixture layer, the first positive electrode mixture layer and the second positive electrode mixture layer each independently include lithium metal phosphorus oxide and lithium transition metal oxide as active materials, a weight of the lithium metal phosphorus oxide included in the first positive electrode mixture layer is greater than a weight of the lithium transition metal oxide, the first positive electrode mixture layer includes a dot type conductive material, and the second positive electrode mixture layer includes a linear conductive material.

Inventors

• Jin Zailan
• Pei Zhixi
• SONG YANHE
• Yan Qingxi

Assignees

• SK新能源株式会社

Dates

Publication Date

20260508

Application Date

20251030

Priority Date

20241101

Claims (11)

1. 1. A positive electrode for a lithium secondary battery comprising a positive electrode current collector and a positive electrode mixture layer on at least one surface of the positive electrode current collector, Wherein the positive electrode mixture layer comprises a first positive electrode mixture layer on a positive electrode current collector and a second positive electrode mixture layer on the first positive electrode mixture layer, The first positive electrode mixture layer and the second positive electrode mixture layer each independently contain lithium metal phosphorus oxide and lithium transition metal oxide as active materials, The weight of lithium metal phosphorus oxide contained in the first positive electrode mixture layer is greater than the weight of lithium transition metal oxide, The first positive electrode mixture layer includes a dot-type conductive material, The second positive electrode mixture layer includes a linear conductive material.
2. 2. The positive electrode for a lithium secondary battery according to claim 1, wherein the first positive electrode mixture layer contains a dot-type conductive material in an amount of 0.3 to 0.5 wt%.
3. 3. The positive electrode for a lithium secondary battery according to claim 1, wherein the content of the linear conductive material contained in the second positive electrode mixture layer is 0.5 to 1.5 wt%.
4. 4. The positive electrode for a lithium secondary battery according to claim 1, wherein the first positive electrode mixture layer further comprises a linear conductive material.
5. 5. The positive electrode for a lithium secondary battery according to claim 1, wherein the second positive electrode mixture layer does not contain a dot-type conductive material.
6. 6. The positive electrode for a lithium secondary battery according to claim 4, wherein the weight of the linear conductive material contained in the first positive electrode mixture layer is less than or equal to the weight of the linear conductive material contained in the second positive electrode mixture layer.
7. 7. The positive electrode for a lithium secondary battery according to claim 4, wherein the first positive electrode mixture layer contains a linear conductive material in an amount of 0.5 to 0.7 wt%.
8. 8. The positive electrode for a lithium secondary battery according to claim 1, wherein the second positive electrode mixture layer further contains a dot-type conductive material, and the content of the dot-type conductive material contained in the second positive electrode mixture layer is 0.1 to 0.5 wt%.
9. 9. The positive electrode for a lithium secondary battery according to claim 1, wherein the dot-shaped conductive material comprises carbon black.
10. 10. The positive electrode for a lithium secondary battery according to claim 1, wherein the linear conductive material comprises Carbon Nanotubes (CNTs).
11. 11. A lithium secondary battery comprising the positive electrode for a lithium secondary battery according to any one of claims 1 to 10.

Description

Positive electrode for lithium secondary battery and lithium secondary battery comprising same Technical Field The present invention relates to a positive electrode for a lithium secondary battery and a lithium secondary battery including the same. Background In recent years, there have been a great deal of research into Electric Vehicles (EVs) that can replace vehicles using fossil fuel, such as gasoline vehicles and diesel vehicles, which are one of the main causes of atmospheric pollution, and as a power source of such Electric Vehicles (EVs), lithium secondary batteries having high discharge voltage and high power stability have been mainly used. In order to improve the performance of the lithium secondary battery, it is necessary to develop a technique capable of improving the energy density, safety, and the like of the positive electrode for the lithium secondary battery. Disclosure of Invention First, the technical problem to be solved According to an aspect of the present invention, a positive electrode for a lithium secondary battery having improved safety may be provided. According to another aspect of the present invention, the energy density of the positive electrode for a lithium secondary battery can be improved. According to another aspect of the present invention, the life performance of the positive electrode for a lithium secondary battery can be improved. (II) technical scheme The positive electrode for a lithium secondary battery according to one specific embodiment includes a positive electrode current collector and a positive electrode mixture layer on at least one side of the positive electrode current collector, wherein the positive electrode mixture layer includes a first positive electrode mixture layer on the positive electrode current collector and a second positive electrode mixture layer on the first positive electrode mixture layer, the first positive electrode mixture layer and the second positive electrode mixture layer each independently include lithium metal phosphorus oxide and lithium transition metal oxide as active materials, a weight of the lithium metal phosphorus oxide included in the first positive electrode mixture layer is greater than a weight of the lithium transition metal oxide, the first positive electrode mixture layer includes a dot-type conductive material, and the second positive electrode mixture layer includes a linear conductive material. In some embodiments, the first positive electrode mixture layer may include a dot-type conductive material in an amount of 0.3 wt% to 0.5 wt%. In some embodiments, the linear conductive material may be included in the second positive electrode mixture layer in an amount of 0.5 wt% to 1.5 wt%. In some embodiments, the first positive electrode mixture layer may further include a linear conductive material. In some embodiments, the second positive electrode mixture layer may not include a dot-type conductive material. In some embodiments, the weight of the linear conductive material contained in the first positive electrode mixture layer may be less than or equal to the weight of the linear conductive material contained in the second positive electrode mixture layer. In some embodiments, the linear conductive material may be included in the first positive electrode mixture layer in an amount of 0.5 wt% to 0.7 wt%. In some embodiments, the second positive electrode mixture layer may further include a dot type conductive material, and the dot type conductive material may be included in the second positive electrode mixture layer in an amount of 0.1 wt% to 0.5 wt%. In some embodiments, the dot-type conductive material may include carbon black. In some embodiments, the linear conductive material may include Carbon Nanotubes (CNTs). A lithium secondary battery according to one embodiment includes the positive electrode for a lithium secondary battery according to any one of the above embodiments. (III) beneficial effects According to one embodiment of the present invention, the stability of the positive electrode for a lithium secondary battery can be improved. According to another embodiment of the present invention, a positive electrode for a lithium secondary battery having a high energy density may be provided. According to another embodiment of the present invention, a positive electrode for a lithium secondary battery having excellent life performance can be provided. Drawings Fig. 1 is a sectional view conceptually showing a positive electrode for a lithium secondary battery according to one specific embodiment. Description of the reference numerals: 100 positive electrode for lithium secondary battery 10 Positive electrode current collector 20 Positive electrode mixture layer 21 First positive electrode mixture layer 22 Second positive electrode mixture layer Detailed Description Hereinafter, the technology disclosed in the present specification and specific embodiments thereof will be described in detail with refere