Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2024282956-A1
Application number	US-202218570729-A
Country	US
Kind code	A1
Filing date	Jun 15, 2022
Priority date	Jun 28, 2021
Publication date	Aug 22, 2024
Grant date	—

Abstract

A lithium secondary battery includes a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material and a nonaqueous electrolyte solution, wherein the positive electrode active material has a lithium composite transition metal oxide having a nickel content of 60 mol % or more in a total transition metal in a form of secondary particles formed by agglomeration of primary particles; and a boron containing coating layer on a surface of all or some of the primary particles, the nonaqueous electrolyte solution comprises a boron dissolved in the nonaqueous electrolyte solution, and a ratio B/A of a boron content (B) in the nonaqueous electrolyte solution to a boron content (A) in the positive electrode active material is 0.001 to 5. The lithium secondary battery according to the present disclosure has improved life characteristics.

First claim

1 . A lithium secondary battery, comprising:
a positive electrode comprising a positive electrode active material, a negative electrode comprising a negative electrode active material and a nonaqueous electrolyte solution, wherein the positive electrode active material comprises a lithium composite transition metal oxide having a nickel content of 60 mol % or more in a total transition metal in a form of secondary particles formed by agglomeration of primary particles; and a boron containing coating layer on a surface of all or some of the primary particles, wherein the nonaqueous electrolyte solution comprises a boron dissolved in the nonaqueous electrolyte solution, and wherein a ratio B/A of a boron content (B) in the nonaqueous electrolyte solution to a boron content (A) in the positive electrode active material is 0.001 to 5.

2 . The lithium secondary battery according to claim 1 , wherein the nonaqueous electrolyte solution comprises a boron containing lithium salt.

3 . The lithium secondary battery according to claim 1 , wherein the nonaqueous electrolyte solution does not comprise a boron containing lithium salt.

4 . The lithium secondary battery according to claim 1 , wherein the B/A is 0.005 to 4.

5 . The lithium secondary battery according to claim 1 , wherein the boron content (A) in the positive electrode active material is 100 to 4,000 ppm, and the boron content (B) in the nonaqueous electrolyte solution is 1 to 3,000 ppm.

6 . The lithium secondary battery according to claim 1 , wherein the boron content (A) in the positive electrode active material is 500 to 2,000 ppm, and the boron content (B) in the nonaqueous electrolyte solution is 10 to 2,000 ppm.

7 . The lithium secondary battery according to claim 1 , wherein the boron content (A) in the positive electrode active material is 500 to 2,000 ppm, the boron content (B) in the nonaqueous electrolyte solution is 10 to 2,000 ppm, and the B/A is 0.005 to 4.

8 . The lithium secondary battery according to claim 1 , wherein the lithium composite transition metal oxide is represented by the following chemical formula 1:
Li a [Ni x Co y M 1 z M 2 w ]O 2   <Chemical formula 1>
where M 1 is at least one of Mn or Al, M 2 is at least one of Zr, B, W, Mo, Cr, Nb, Mg, Hf, Ta, La, Ti, Sr, Ba, Ce, F, P, S or Y, and
0.9≤ a≤ 1.3,0.6≤ x< 1.0,0< y≤ 0.4,0< z≤ 0.4, 0≤ w≤ 0.4, x+y+z+w= 1.

9 . The lithium secondary battery according to claim 1 , wherein an average particle size of the primary particles is 0.1 to 8 μm, and a D50 of the secondary particles is 2 to 15 μm.

10 . The lithium secondary battery according to claim 1 , wherein the coating layer comprises at least one selected from the group consisting of a lithium boron oxide and a boron oxide.

Assignees

• Lg Energy Solution Ltd

Inventors

• Lee Dong-Hun
• Kong Woo-Yeon
• Kim Hye-Mi
• Park Sin-Yong
• Lee Sang-Wook
• Kim Je-Young
• Jung Wang-Mo

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

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

• H01M10/0568

  characterised by the solutes · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/366 Primary

  as layered products · CPC title