Method of preparing positive electrode active material for secondary battery and secondary battery using the same

Patent metadata

Field	Value
Publication number	US-11764347-B2
Application number	US-201816652830-A
Country	US
Kind code	B2
Filing date	Oct 17, 2018
Priority date	Oct 20, 2017
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

Provided is a method of preparing a positive electrode active material, which includes preparing a mixture by mixing a lithium compound, a transition metal precursor, and a metal oxide additive, and sintering the mixture to form a lithium transition metal oxide, wherein the sintering is performed through two-stage temperature holding sections, a temperature of a first temperature holding section is in a range of 400° C. to 650° C., and a temperature of a second temperature holding section is in a range of 700° C. to 900° C. A positive electrode including a positive electrode active material prepared according to the method, and a lithium secondary battery including the positive electrode is also provided.

First claim

The invention claimed is:

1. A method of preparing a positive electrode active material, comprising:
sintering a mixture to form a positive electrode active material that comprises a lithium transition metal oxide,
wherein the mixture includes a lithium compound, a transition metal precursor, and a metal oxide additive, and
wherein the sintering comprising:
sintering in a first temperature holding section having a temperature in a range of 400° C. to 650° C. for a first holding time; and
sintering in a second temperature holding section having a temperature in a range of 700° C. to 900° C. for a second holding time to form the positive electrode active material.

2. The method of claim 1 , wherein the metal oxide additive comprises at least one of ZrO 2 , ZnO, Nb 2 O 5 , MgO, Fe 2 O 3 , V 2 O 5 , WO 3 , SiO, SiO 2 , or Sn 2 O 3 .

3. The method of claim 1 , wherein the metal oxide additive is mixed in an amount of 0.01 wt % to 1.0 wt % based on a combined weight of the lithium compound and the transition metal precursor.

4. The method of claim 1 , wherein, when an average particle diameter (D 50 ) of the transition metal precursor is in a range of 5 μm to 10 μm, the temperature of the first temperature holding section is in the range of 400° C. to 600° C.

5. The method of claim 1 , wherein an average particle diameter (D 50 ) of the transition metal precursor is greater than 10 μm, the temperature of the first temperature holding section is in the range of 500° C. to 650° C.

6. The method of claim 1 , wherein the transition metal precursor comprises at least one of nickel (Ni), cobalt (Co), or manganese (Mn).

7. The method of claim 6 , wherein the transition metal precursor is Ni a1 CO b1 Mn c1 M d1 (OH) 2 ,
wherein M comprises at least one of aluminum (Al), zirconium (Zr), magnesium (Mg), zinc (Zn), yttrium (Y), iron (Fe), tungsten (W), and titanium (Ti), and 0.4≤a1≤1.0, 0≤b1≤ 0.6, 0≤c1≤0.6, 0≤d1≤0.2, and a1+b1+c1+d1=1.

8. The method of claim 7 , wherein the transition metal precursor includes Ni in an amount of 70 mol % or more based on a total transition metals.

9. The method of claim 1 , wherein a first heating rate before reaching the first temperature holding section is in a range of 1.0° C./min to 3.0° C./min.

10. The method of claim 1 , wherein a second heating rate before reaching the second temperature holding section from the first temperature holding section is in a range of 1.0° C./min to 3.0° C./min.

11. The method of claim 1 , wherein the first holding time of the first temperature holding section is in a range of 2 hours to 8 hours.

12. The method of claim 1 , wherein the second holding time of the second temperature holding section is in a range of 4 hours to 12 hours.

Assignees

• Lg Chemical Ltd

Inventors

• Baek Hyeon Hui
• Ban Sung Ho
• Eom Jun Ho
• Park Na Ri

Classifications

• H01M4/131 Primary

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

• C01G53/44 Primary

  containing manganese · CPC title

• H01M4/0471 Primary

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/505

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

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title