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

Patent metadata

Field	Value
Publication number	US-12401031-B2
Application number	US-202117512548-A
Country	US
Kind code	B2
Filing date	Oct 27, 2021
Priority date	Mar 25, 2021
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

A cathode active material for a lithium secondary battery according to embodiments of the present invention has a high-nickel composition and includes a lithium-nickel composite metal oxide particle in which lithium, nickel and a metal having an oxidation number of +2 are combined in a predetermined range. A cation disorder caused when a nickel ion is present at a lithium-ion site is reduced to improve structural stability of the cathode active material. An initial capacity and a battery efficiency of a lithium secondary battery can be improved using the cathode active material.

First claim

What is claimed is:

1. A cathode active material for a lithium secondary battery, comprising:
a lithium-nickel composite metal oxide particle represented by Chemical Formula 1 and having a secondary particle structure in which a plurality of primary particles are aggregated; and
at least one of a metal sulfate component, a metal carbonate component and a metal oxide component which is present between the primary particles in an inner region of the lithium-nickel composite metal oxide particle,
wherein the metal sulfate component, the metal carbonate component and the metal oxide component each contains M1 in Chemical Formula 1:
Li a Ni x M1 y M2 1-x O b   [Chemical Formula 1]

wherein, in Chemical Formula 1, 0<a≤1.1, 1.98≤b≤2.2, 0.8≤x<0.98, y is a molar ratio of M1 corresponding to a weight greater than 0 wt % and 2.5 wt % or less of a weight of Ni,
M1 is at least one element selected from the group consisting of Sr and Ra, and M1 is present between the primary particles in the inner region of the secondary particle structure of the lithium-nickel composite metal oxide particle, and
M2 includes Mn and Co,
wherein the cathode active material is made by:
preparing an active material precursor obtained by mixing and reacting active material metal salts;
mixing the active material precursor, a sulfate remaining from the preparation of the active material precursor, M1 source and a lithium source; and
reacting the active material precursor, remaining sulfates, M1 source and a lithium source by a heat treatment to form the at least one of the metal sulfate component, the metal carbonate component or the metal oxide component present between the primary particles in the inner region of the lithium-nickel composite metal oxide particle.

2. The cathode active material for a lithium secondary battery according to claim 1 , wherein a weight ratio of M1 is from 0.01 wt % to 1.4 wt % based on the weight of Ni.

3. The cathode active material for a lithium secondary battery according to claim 1 , wherein, in Chemical Formula 1, 0.0002≤y≤0.02.

4. The cathode active material for a lithium secondary battery according to claim 1 , wherein, in Chemical Formula 1, 0.001≤y≤0.01.

5. The cathode active material for a lithium secondary battery according to claim 1 , wherein, in Chemical Formula 1, M2 further comprises at least one element selected from the group consisting of B, Al, Si, Ti, V, Fe, Cu, Zn, Y, Zr, Mo, Sn and W.

6. The cathode active material for a lithium secondary battery according to claim 1 , wherein, in Chemical Formula 1, 0.8≤x≤0.95.

7. A lithium secondary battery, comprising:
a cathode comprising the cathode active material layer for a lithium secondary battery of claim 1 ; and
an anode facing the cathode.

Assignees

• Sk Innovation Co Ltd
• Sk On Co Ltd

Inventors

• Noh Mi Jung
• Kim Jik Soo
• Choi Jae Ho
• Lee Tae Kyoung
• Kim Sang Bok
• Park Sang Min

Classifications

• H01M2004/028

  Positive electrodes · 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

• H01M4/505

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

• C01P2006/40

  Electric properties · CPC title