Negative electrode active material, negative electrode including the same and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-2021351432-A1
Application number	US-202117382544-A
Country	US
Kind code	A1
Filing date	Jul 22, 2021
Priority date	Jun 2, 2016
Publication date	Nov 11, 2021
Grant date	—

Abstract

The present invention relates to a negative electrode active material which includes a secondary particle including a first particle which is a primary particle, wherein the first particle includes a first core and a first surface layer which is disposed on a surface of the first core and contains carbon, and the first core includes a metal compound which includes one or more of a metal oxide and a metal silicate and one or more of silicon and a silicon compound; a method of preparing the same; an electrode including the same; and a lithium secondary battery including the same.

First claim

1 . A negative electrode active material, comprising a secondary particle including a first particle which is a primary particle and a second particle which is a primary particle,
wherein the first particle includes a first core, and a first surface layer which is disposed on a surface of the first core and contains carbon, and the first core includes: one or more of silicon and a silicon compound; and a metal compound which includes one or more of a metal oxide and a metal silicate, wherein the secondary particle further includes a second particle which is a primary particle, the second particle includes a second core and a second surface layer which is disposed on a surface of the second core and contains carbon, and the second core includes one or more of silicon and a silicon compound.

2 . The negative electrode active material according to claim 1 , wherein the metal compound is doped in an amount of 1 to 50 wt % based on the total weight of the first particle.

3 . The negative electrode active material according to claim 1 , wherein a weight ratio of the first particle and the second particle is in a range of 1:0.25 to 1:4.

4 . The negative electrode active material according to claim 1 , wherein an average particle size D 50 of each of the first core and the second core is in a range of 0.5 to 20 μm.

5 . The negative electrode active material according to claim 1 , wherein the silicon included in each of the first core and the second core includes one or more of an amorphous silicon and a crystalline silicon having a crystal size of more than 0 to 30 nm or less.

6 . The negative electrode active material according to claim 1 , wherein the silicon compound included in each of the first core and the second core is a silicon oxide (SiO x , 0<x<2) in which silicon is dispersed in a silicon dioxide (SiO 2 ) matrix.

7 . The negative electrode active material according to claim 1 , wherein the first core and the second core is a porous core including a plurality of pores.

8 . The negative electrode active material according to claim 7 , wherein an internal porosity of the porous core is in a range of 5% to 90% based on the total volume of the porous core.

9 . The negative electrode active material according to claim 1 , wherein the metal oxide includes an oxide of one or more metals selected from the group consisting of lithium (Li), magnesium (Mg), aluminum (Al), calcium (Ca), and titanium (Ti).

10 . The negative electrode active material according to claim 1 , wherein the metal silicate includes a silicate of one or more metals selected from the group consisting of lithium (Li), magnesium (Mg), aluminum (Al), calcium (Ca), and titanium (Ti).

11 . The negative electrode active material according to claim 1 , wherein a thickness of the first surface layer and the second surface layer is in a range of 1 to 100 nm.

12 . The negative electrode active material according to claim 1 , wherein the secondary particle has an average particle size D 50 in a range of 2 to 50 μm.

13 . The negative electrode active material according to claim 1 , wherein the negative electrode active material further comprises a carbon layer which is disposed on a surface of the secondary particle and contains carbon.

14 . The negative electrode active material according to claim 13 , wherein a thickness of the carbon layer is in a range of 5 to 100 nm.

15 . The negative electrode active material according to claim 1 , wherein the secondary particle further includes a crystalline carbon-based material which is a primary particle.

16 . The negative electrode active material according to claim 1 , wherein the negative electrode active material further comprises a graphite-based active material particle.

17 . A negative electrode, comprising the negative electrode active material according to claim 1 .

18 . A lithium secondary battery, comprising the negative electrode according to claim 17 .

Assignees

• Lg Chemical Ltd

Inventors

• Choi Jung Hyun
• Lee Yong Ju
• Kim Eun Kyung

Classifications

• H01M4/386 Primary

  Silicon or alloys based on silicon · CPC title

• H01M4/366

  as layered products · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M10/0525 Primary

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