Positive Electrode Active Material, Positive Electrode Including the Same, and Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2024351914-A1
Application number	US-202218688074-A
Country	US
Kind code	A1
Filing date	Sep 8, 2022
Priority date	Sep 10, 2021
Publication date	Oct 24, 2024
Grant date	—

Abstract

present disclosure A positive electrode active material and a method for preparing the same are provided. The method for preparing a positive electrode material present disclosure—includes the steps of mixing a transition metal precursor and a lithium raw material and primarily sintering the mixture to prepare a lithium nickel-based oxide in the form of single particles or quasi-single particles, secondarily sintering the lithium nickel-based oxide in the form of single particles or quasi-single particles, and mixing the secondarily sintered lithium nickel-based oxide and a boron raw material and then heat-treating the mixture to form a coating layer.

First claim

1 . A method for preparing a positive electrode active material, the method comprising the steps of:
mixing a transition metal precursor and a lithium raw material to form a mixture and primarily sintering the mixture at a temperature from 800° C. to 1,000° C. to prepare a lithium nickel-based oxide having a form of at least one of single particles or quasi-single particles; secondarily sintering the lithium nickel-based oxide at 600° C. to 800° C. to form the secondarily sintered lithium nickel-based oxide; and mixing the secondarily sintered lithium nickel-based oxide and a boron raw material and then heat-treating to form a coating layer.

2 . The method of claim 1 , wherein the transition metal precursor is a nickel cobalt manganese hydroxide having a Ni content of 80 mol % or more.

3 . The method of claim 1 , wherein the lithium nickel-based oxide has composition represented by Formula 1 below:
Li a Ni b Co c M 1 d M 2 e O 2   [Formula 1]
wherein, M 1 is Mn, Al, or a combination thereof, M 2 is at least one selected from the group consisting of Zr, W, Y, Ba, Ca, Ti, Mg, Ta, and Nb, 0.8≤a≤1.2, 0.8≤b<1, 0<c<0.2, 0<d<0.2, and 0≤e≤0.1.

4 . The method of claim 1 , wherein the primarily sintering is performed at a temperature—from 800° C. to 950° C.

5 . The method of claim 1 , wherein the primarily sintering is performed in an oxygen atmosphere for 6 hours to 35 hours.

6 . The method of claim 1 , wherein the secondarily sintering is performed at a temperature from 650° C. to 750° C.

7 . The method of claim 1 , wherein the secondarily sintering is performed in an oxygen atmosphere for 2 hours to 10 hours.

8 . The method of claim 1 , wherein the heat treating is performed at a temperature from 200° C. to 500° C.

9 . The method of claim 1 , wherein the method does not include washing.

10 . A positive electrode active material comprising:
a lithium nickel-based oxide having a composition represented by Formula 1 below and having a form of at least one of single particles or quasi-single particles; and a coating layer formed on the surface of the lithium nickel-based oxide, wherein the coating layer includes boron (B), wherein a spinel-like phase is included on the surface of the lithium nickel-based oxide:
Li a Ni b Co c M 1 d M 2 e O 2   [Formula 1]

wherein, M 1 is Mn, Al, or a combination thereof, M 2 is at least one selected from the group consisting of Zr, W, Y, Ba, Ca, Ti, Mg, Ta, and Nb, 0.8≤a≤1.2, 0.8≤b<1, 0<c<0.2, 0<d<0.2 and 0≤e≤0.1.

11 . The positive electrode active material of claim 10 , wherein the single particles are particles composed of a single nodule, and the quasi-single particles are complexes of at most 30 nodules.

12 . The positive electrode active material of claim 10 , wherein the positive electrode active material has a residual lithium amount of 0.5 wt % or less.

13 . The positive electrode active material of claim 11 , wherein the positive electrode active material has an average particle diameter of nodules of 0.5 μm to 3 μm.

14 . The positive electrode active material of claim 10 , wherein when the positive electrode active material included a coin-half cell,
a ratio R 10 /R 90 of resistance at SOC 10 to resistance at SOC 90 measured while charging a coin-half cell to 4.25 V and discharging to 2.5 V at 0.1 C/0.1 C is 3 or less, and a resistance increase rate is 100% or less when charging and discharging the coin-half cell at 45° C. to 2.5-4.25 V at 0.1 C/0.1 C is set as 1 cycle, and 50 cycles of charging and discharging.

15 . A positive electrode comprising a positive electrode active material layer comprising the positive electrode active material of claim 10 .

16 . A lithium secondary battery comprising the positive electrode of claim 15 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Hwang Jin Tae
• Jung Wang Mo
• Jo Chi Ho
• Yoo Tae Gu
• Jung Hae Jung
• Heo Jong Wook
• Cho Hyeon Jin

Classifications

• C01G53/506

  with the molar ratio of nickel with respect to all the metals other than alkali metals higher than or equal to 0.8, e.g. Li(MzNixCoyMn1-x-y-z)O2 with x ≥ 0.8 · CPC title

• C01G53/42

  containing alkali metals, e.g. LiNiO2 · CPC title

• H01M10/0427

  Button cells · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title