Cathode active material for lithium secondary battery and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-2026005238-A1
Application number	US-202519249982-A
Country	US
Kind code	A1
Filing date	Jun 25, 2025
Priority date	Jun 26, 2024
Publication date	Jan 1, 2026
Grant date	—

Abstract

Embodiments of the present disclosure relate to a cathode active material for lithium secondary battery including lithium-transition metal composite oxide particles. In the lithium-transition metal composite oxide particles, a (105) plane FWHM ratio measured through in-situ X-ray diffraction (XRD) and defined by Equation 1 is less than or equal to 600%. The life characteristics of a lithium secondary battery can be improved by preventing deformation of a lattice structure and/or crystal structure within the lithium-transition metal composite oxide particles.

First claim

What is claimed is:

1 . A cathode active material for lithium secondary battery including lithium-transition metal composite oxide particles in which a (105) plane FWHM ratio measured through in-situ X-ray diffraction (XRD) and defined by Equation 1 below is less than or equal to 600%:

(
105
)

⁢

plane
⁢

FWHM
⁢

ratio
⁢

(
%
)

=

100
*

(

FWHM
max

(
105
)

/

FWHM
min

(
105
)

)

[

Equation
⁢

1

]

where FWHM max (105) is a maximum FWHM value of a (105) plane peak of the lithium-transition metal composite oxide particles measured through the in-situ XRD, and
FWHM min (105) is a minimum FWHM value of the (105) plane peak of the lithium-transition metal composite oxide particles measured through the in-situ XRD.

2 . The cathode active material for lithium secondary battery of claim 1 , wherein the (105) plane FWHM ratio is 450 to 550%.

3 . The cathode active material for lithium secondary battery of claim 1 , wherein the (105) plane FWHM ratio is 512 to 552%.

4 . The cathode active material for lithium secondary battery of claim 1 , wherein the FWHM max (105) is 0.5 to 1.0.

5 . The cathode active material for lithium secondary battery of claim 1 , wherein the FWHM min (105) is 0.1 to 0.16.

6 . The cathode active material for lithium secondary battery of claim 1 , wherein a change in a FWHM value of the (105) plane peak of the lithium-transition metal composite oxide particles based on a charge and a discharge of the lithium secondary battery is measured in real time through the in-situ XRD.

7 . The cathode active material for lithium secondary battery of claim 1 , wherein the lithium-transition metal composite oxide particles include at least one doping element.

8 . The cathode active material for lithium secondary battery of claim 1 , wherein the lithium-transition metal composite oxide particles have a secondary particle structure including a plurality of primary particles.

9 . The cathode active material for lithium secondary battery of claim 8 , wherein the secondary particle structure includes 2 to 5 primary particles.

10 . The cathode active material for lithium secondary battery of claim 1 , wherein the lithium-transition metal composite oxide particles have a single crystal structure.

11 . The cathode active material for lithium secondary battery of claim 1 , wherein the lithium-transition metal composite oxide particles are represented by formula 1 below:

where M includes at least one of Ti, Zr, Al, Mg or W, and
0.8<x<1.5, 0.70≤a≤0.98, 0≤b≤0.20, 0.02≤c≤0.30, 0≤d≤0.05, 0.985a+b+c≤1.02, and −0.1≤y≤0.1.

12 . The cathode active material for lithium secondary battery of claim 11 , wherein in the Formula 1, 0.85≤a≤0.98.

13 . A lithium secondary battery comprising:
a cathode including a cathode active material layer including a cathode active material for lithium secondary battery according to claim 1 ; and an anode opposite the cathode.

Assignees

• Sk On Co Ltd

Inventors

• Lim Byoung Beom
• Kang Min Suk
• Do Ji Yae
• Lee Sang Wook
• Lee Sang Han
• Cho Yong Hyun

Classifications

• C01P2004/50

  Agglomerated particles · CPC title

• C01P2002/52

  containing elements as dopants · CPC title

• C01P2002/54

  one element only · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2002/70

  defined by measured X-ray, neutron or electron diffraction data · CPC title