Method of Preparing Positive Electrode Material for Lithium Secondary Battery and Positive Electrode Material for Lithium Secondary Battery Prepared Thereby

Patent metadata

Field	Value
Publication number	US-2021265615-A1
Application number	US-201917252805-A
Country	US
Kind code	A1
Filing date	Sep 11, 2019
Priority date	Sep 14, 2018
Publication date	Aug 26, 2021
Grant date	—

Abstract

A method of preparing a positive electrode material is provided. The method includes mixing a first positive electrode active material precursor having an average particle diameter (D50) of 10 μm to 30 μm with a lithium-containing raw material and pre-sintering the mixture to obtain a first pre-sintered product, mixing a second positive electrode active material precursor having an average particle diameter (D50) different from that of the first positive electrode active material precursor with a lithium-containing raw material and pre-sintering the mixture to obtain a second pre-sintered product, disintegrating each of the first pre-sintered product and the second pre-sintered product, and mixing the disintegrated first pre-sintered product and the disintegrated second pre-sintered product and main-sintering the mixture to obtain a positive electrode material.

First claim

1 . A method of preparing a positive electrode material, comprising:
mixing a first positive electrode active material precursor having an average particle diameter (D 50 ) of 10 μm to 30 μm with a lithium-containing raw material, and pre-sintering the mixture to obtain a first pre-sintered product; mixing a second positive electrode active material precursor having an average particle diameter (D 50 ) different from the average particle diameter (D 50 ) of the first positive electrode active material precursor with a lithium-containing raw material, and pre-sintering the mixture to obtain a second pre-sintered product; disintegrating each of the first pre-sintered product and the second pre-sintered product; and mixing the disintegrated first pre-sintered product and the disintegrated second pre-sintered product, and main-sintering the mixture to obtain a positive electrode material.

2 . The method of claim 1 , wherein the first positive electrode active material precursor and the lithium-containing raw material are mixed in an equivalence ratio of 1:1.03 to 1.1.

3 . The method of claim 1 , wherein the second positive electrode active material precursor and the lithium-containing raw material are mixed in an equivalence ratio of 1:1.01 to 1.07.

4 . The method of claim 1 , wherein the second positive electrode active material precursor has an average particle diameter (D 50 ) of 3 μm to 7 μm.

5 . The method of claim 1 , wherein the pre-sintering of the mixture to obtain the first pre-sintered product and the pre-sintering of the mixture to obtain the second pre-sintered product are performed in a temperature range of 500° C. to 800° C. for 3 hours to 24 hours.

6 . The method of claim 1 , wherein the disintegrated first pre-sintered product and the disintegrated second pre-sintered product are mixed in a weight ratio of 0.5 to 0.9:0.5 to 0.1.

7 . The method of claim 1 , wherein the main-sintering is performed in a temperature range of 700° C. to 950° C. for 3 hours to 24 hours.

8 . The method of claim 1 , further comprising a washing process after the positive electrode material is obtained.

9 . The method of claim 1 , wherein the first positive electrode active material precursor and the second positive electrode active material precursor are each independently represented by Formula 1:
Ni x Co y M 1 (1−x−y) (OH) 2   [Formula 1]
wherein, M 1 is at least one selected from the group consisting of manganese (Mn) or aluminum (Al), 0.6≤x<1.0, 0≤y<0.4, and 0.6≤x+y≤1.0.

10 . A positive electrode material comprising:
a first positive electrode active material having an average particle diameter (D 50 ) of 10 μm to 30 μm; and a second positive electrode active material having a smaller average particle diameter than the first positive electrode active material, wherein an equivalent weight of lithium in the first positive electrode active material and an equivalent weight of lithium in the second positive electrode active material are different.

11 . The positive electrode material of claim 10 , wherein the second positive electrode active material has an average particle diameter (D 50 ) of 3 μm to 7 μm.

12 . The positive electrode material of claim 10 , wherein the first positive electrode active material is represented by Formula 2, and the second positive electrode active material is represented by Formula 3,
Li 1+a1 Ni x1 Co y1 M 1 (1−x1−y1) M 2 w1 O 2   [Formula 2]
wherein, in Formula 2, M 1 is at least one selected from the group consisting of manganese (Mn) or aluminum (Al), M 2 is at least one selected from the group consisting of tungsten (W), copper (Cu), iron (Fe), vanadium (V), chromium (Cr), titanium (Ti), zirconium (Zr), zinc (Zn), aluminum (Al), Indium (In), tantalum (Ta), yttrium (Y), lanthanum (La), strontium (Sr), gallium (Ga), scandium (Sc), gadolinium (Gd), samarium (Sm), calcium (Ca), cerium (Ce), niobium (Nb), magnesium (Mg), boron (B), and molybdenum (Mo), 0.002≤a1≤0.1, 0.6≤x1≤1.0, 0<y1≤0.4, 0.6≤x1+y1≤1.0, and 0≤w1≤0.05;
Li 1+a2 Ni x2 Co y2 M 1 (1−x2−y2) M 2 w2 O 2   [Formula 3]

wherein, in Formula 3, M 1 is at least one selected from the group consisting of Mn or Al, M 2 is at least one selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, 0.002≤a2≤0.1, 0.6≤x2≤1.0, 0<y2≤0.4, 0.6≤x2+y2≤1.0, and 0≤w2≤0.05.

13 . The positive electrode material of claim 10 , wherein the first positive electrode active material and the second positive electrode active material are included in a weight ratio of 0.5 to 0.9:0.5 to 0.1.

14 . The positive electrode material of claim 10 , wherein the positive electrode material has a tap density of 2.8 g/cc to 4.0 g/cc.

15 . A positive electrode for a lithium secondary battery, the positive electrode comprising the positive electrode material of claim 10 .

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

Assignees

• Lg Chemical Ltd

Inventors

• Choi Sang Soon
• Chae Hwa Seok
• Kim Jae Geun
• Kang Seong Hoon

Classifications

• C04B2235/3286

  Gallium oxides, gallates, indium oxides, indates, thallium oxides, thallates or oxide forming salts thereof, e.g. zinc gallate · CPC title

• C04B2235/6567

  Treatment time · 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

• H01M2004/028

  Positive electrodes · CPC title

• C04B2235/3227

  Lanthanum oxide or oxide-forming salts thereof · CPC title