Positive Electrode Including Positive Electrode Additive for Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2024194857-A1
Application number	US-202218285784-A
Country	US
Kind code	A1
Filing date	Aug 12, 2022
Priority date	Aug 12, 2021
Publication date	Jun 13, 2024
Grant date	—

Abstract

A positive electrode with excellent life characteristics and high capacity is provided by using a positive electrode additive of ZrO 2-x (0<x<2) to complement structural stability of a high-nickel positive electrode active material. A method of preparing the same, and a lithium secondary battery including the positive electrode are also provided.

First claim

1 . A positive electrode comprising:
a positive electrode active material layer including a positive electrode active material, a conductive agent, a binder, and a positive electrode additive, wherein the positive electrode additive is ZrO 2-x , wherein 0<x<2.

2 . The positive electrode of claim 1 , wherein the positive electrode active material comprises a lithium transition metal oxide represented by Formula 1;
Li a Ni 1-x-y Co x M 1 y M 2 z O 2   [Formula 1]
wherein, in Formula 1, M 1 is aluminum (Al), manganese (Mn), or a combination thereof, M 2 is at least one element selected from the group consisting of zirconium (Zr), titanium (Ti), magnesium (Mg), tantalum (Ta), niobium (Nb), tungsten (W), molybdenum (Mo), and chromium (Cr), and 1.0≤a≤1.3, 0<x<0.4, 0<y<0.4, 0≤z≤0.1, and 0.6≤1-x-y<1.0.

3 . The positive electrode of claim 1 , wherein the positive electrode additive has an average particle diameter (D 50 ) of 200 nm to 50 μm.

4 . The positive electrode of claim 1 , wherein the ZrO 2-x satisfies Equation 1:
5< P 1/ P 2<8  [Equation 1]
wherein, in Equation 1, P1 is an intensity of a peak in a 2θ range of 29° or more to 31° or less on XRD, and P2 is an intensity of a peak in a 2θ range of 35° or more to 37° or less on XRD.

5 . The positive electrode of claim 1 , wherein the positive electrode additive has a tetragonal crystal structure.

6 . The positive electrode of claim 1 , wherein the positive electrode additive has a band gap energy of 3.0 eV or less.

7 . The positive electrode of claim 1 , wherein the positive electrode additive is included in an amount of 1 wt % to 5 wt % based on a total weight of the positive electrode active material layer.

8 . A lithium secondary battery comprising the positive electrode of claim 1 .

9 . A method of preparing a positive electrode, the method comprising:
preparing ZrO 2-x (0<x<2) by reducing a precursor containing zirconium (Zr); preparing a positive electrode slurry by mixing the ZrO 2-x , as a positive electrode additive, with a positive electrode active material, a conductive agent, and a binder; and preparing a positive electrode active material layer by using the positive electrode slurry.

10 . The method of claim 9 , wherein the precursor is at least one selected from acetate, sulfate, and nitrate of Zr.

11 . The method of claim 9 , wherein the ZrO 2-x (0<x<2) is prepared by performing a heat treatment on a precursor solution containing zirconium in a reducing atmosphere.

12 . The method of claim 11 , wherein the reducing atmosphere is formed by hydrogen and argon.

13 . The method of claim 11 , wherein the heat treatment is performed at a temperature of 500° C. to 700° C.

Assignees

• Lg Energy Solution Ltd
• Univ Sookmyung Womens Ind Acad Coop Found

Inventors

• Jo Chi Ho
• Jung Wang Mo
• Ryu Won Hee
• Kim You Jin
• Kim Su Ji

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/0402

  Methods of deposition of the material · CPC title

• H01M4/0471

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

• H01M4/1391

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

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title