Cathode active material and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-12136733-B2
Application number	US-202117508435-A
Country	US
Kind code	B2
Filing date	Oct 22, 2021
Priority date	Oct 22, 2020
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

The cathode active material according to embodiments of the present invention includes a lithium composite oxide particle having a form of secondary particle in which a plurality of primary particle are aggregated, wherein the primary particles respectively include a lithium conduction pathway through which lithium ions are diffused. Wherein the primary particles include a first particle, and the first particle has an angle of 45° to 90° formed by a direction from a center of the first particle to a center of the lithium composite oxide particle and a direction of the lithium conduction pathway included in the first particle, wherein a ratio of the number of the first particles among the primary particles located on a surface of the lithium composite oxide particle is 20% or more.

First claim

What is claimed is:

1. A cathode active material comprising:
a lithium composite oxide particle having the form of a secondary particle in which a plurality of primary particles are aggregated, wherein the plurality of primary particles respectively include a lithium conduction pathway through which lithium ions are diffused,
wherein the plurality of primary particles include a plurality of first particles, and each of the plurality of first particles has a hexagonal crystal structure and an angle of 45° to 90° formed by a direction from a center of each of the plurality of first particles to a center of the lithium composite oxide particle and a direction of the lithium conduction pathway included in the plurality of first particles,
wherein a ratio of the number of the plurality of first particles among the plurality of primary particles located on a surface of the lithium composite oxide particle is 20% or more,
wherein the plurality of primary particles include a plurality of second particles, and each of the plurality of second particles has a hexagonal crystal structure and an angle of less than 45° formed by a direction from a center of each of the plurality of second particles to a center of the lithium composite oxide particle and a direction of the lithium conduction pathway included in the plurality of second particles and
wherein the plurality of primary particles only include the plurality of first particles and the plurality of second particles,
wherein the lithium conduction pathway is formed in an ab-axis direction of the hexagonal crystal structure.

2. The cathode active material according to claim 1 , wherein at least one of the plurality of first particles has a triangular shape.

3. The cathode active material according to claim 1 , wherein the lithium composite oxide particle has a specific surface area of 0.25 m2/g or less.

4. The cathode active material according to claim 1 , wherein a mole fraction of nickel among elements except for lithium and oxygen of the lithium composite oxide particle is 0.6 or more.

5. The cathode active material according to claim 1 , wherein the lithium composite oxide particle has a strength of 120 Mpa or more.

6. A lithium secondary battery comprising:
a cathode comprising the cathode active material according to claim 1 ,
an anode, and
a separation membrane interposed between the cathode and the anode.

Assignees

• Sk Innovation Co Ltd
• Sk On Co Ltd

Inventors

• Park Sung Soon
• Choi Ji Hoon
• Kim Jik Soo
• Lee Kwang Ho
• Jeun Jeong Hoon

Classifications

• H01M2250/30

  Fuel cells in portable systems, e.g. mobile phone, laptop · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/362

  Composites · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title