Positive electrode material and preparation method therefor, and lithium-ion battery

Patent metadata

Field	Value
Publication number	US-2024120476-A1
Application number	US-202318527378-A
Country	US
Kind code	A1
Filing date	Dec 4, 2023
Priority date	Jun 4, 2021
Publication date	Apr 11, 2024
Grant date	—

Abstract

The present disclosure provides a cobalt-free and nickel-free positive electrode material and a preparation method therefor, and a battery. The preparation method includes: preparing a cobalt-free and nickel-free matrix material, and mixing the cobalt-free and nickel-free matrix material, a lithium source, and a divalent manganese compound for reaction to obtain the cobalt-free and nickel-free positive electrode material. By adding the divalent manganese compound, the generation of lamellar LiMnO 2 and spinel LiMn 2 O 4 is inhibited, the generation of lamellar Li 2 MnO 3 is promoted, and the cycle performance of the material is improved.

First claim

1 . A preparation method for a cobalt-free and nickel-free positive electrode material, comprising: preparing a cobalt-free and nickel-free matrix material, and mixing the cobalt-free and nickel-free matrix material, a lithium source, and a divalent manganese compound for reaction to obtain the cobalt-free and nickel-free positive electrode material.

2 . The preparation method according to claim 1 , wherein a general formula of the cobalt-free and nickel-free matrix material is Na x Li y Mn 0.75 O 2 , wherein 0.8≤x≤1, and 0≤y≤0.35.

3 . The preparation method according to claim 1 , wherein a preparation method for the cobalt-free and nickel-free matrix material comprises: mixing a lithium salt, a manganese salt, and a sodium salt, wherein a molar ratio of lithium in the lithium salt, sodium in the sodium salt, and manganese in the manganese salt is (0.2-0.3): (0.9-1.1): (0.65-0.85); and heating the mixture to obtain the cobalt-free and nickel-free matrix material.

4 . The preparation method according to claim 3 , wherein a temperature of the heating in the preparation method for the cobalt-free and nickel-free matrix material is 500-800° C., and time for the heating is 8-12 h.

5 . The preparation method according to claim 1 , wherein a temperature of the heating in the preparation method for the cobalt-free and nickel-free matrix material is 500-800° C., and time for the heating is 8-12 h.

6 . The preparation method according to claim 1 , wherein the cobalt-free and nickel-free matrix material, the divalent manganese compound, and the lithium source are mixed to obtain a mixture, and a molar ratio of lithium to manganese in the mixture is (0.8-1.5):1.

7 . The preparation method according to claim 6 , wherein the divalent manganese compound comprises one of or a combination of at least two of MnO, Mn 3 O 4 , or MnCO 3 .

8 . The preparation method according to claim 6 , wherein the mixing reaction is a melting reaction, a temperature of the mixing reaction is 400-800° C., and time for the mixing reaction is 4-8 h.

9 . The preparation method according to claim 1 , wherein the divalent manganese compound comprises one of or a combination of at least two of MnO, Mn 3 O 4 , or MnCO 3 .

10 . The preparation method according to claim 1 , wherein the mixing reaction is a melting reaction, a temperature of the mixing reaction is 400-800° C., and time for the mixing reaction is 4-8 h.

11 . The preparation method according to claim 1 , wherein the cobalt-free and nickel-free positive electrode material obtained after the mixing reaction is further coated, and a method for the coating comprises the following steps: mixing the cobalt-free and nickel-free positive electrode material obtained by the reaction with AlPO 4 , and performing primary calcination to obtain an AlPO 4 -coated positive electrode material; and mixing the AlPO 4 -coated positive electrode material with TiO 2 , and performing secondary calcination to obtain an AlPO 4 - and TiO 2 -coated cobalt-free and nickel-free positive electrode material.

12 . The preparation method according to claim 11 , wherein a temperature of the primary calcination is 300-800° C., time for the primary calcination is 5-8 h, and an atmosphere for the primary calcination is air or oxygen.

13 . The preparation method according to claim 11 , wherein a temperature of the secondary calcination is 300-800° C., time for the secondary calcination is 5-8 h, and an atmosphere for the secondary calcination is air or oxygen.

14 . The preparation method according to claim 11 , wherein based on a total mass of the cobalt-free and nickel-free positive electrode material, a coating amount of the AlPO 4 is 500-5000 ppm, and a coating amount of the TiO 2 is 500-5000 ppm.

15 . The preparation method according to claim 1 , wherein based on a total mass of the cobalt-free and nickel-free positive electrode material, a coating amount of the AlPO 4 is 500-5000 ppm, and a coating amount of the TiO 2 is 500-5000 ppm.

16 . A cobalt-free and nickel-free positive electrode material prepared by the preparation method according to claim 1 , wherein the cobalt-free and nickel-free positive electrode material comprises lamellar LiMnO 3 , spinel LiMn 2 O 4 , and lamellar Li 2 MnO 3 .

17 . The cobalt-free and nickel-free positive electrode material according to claim 16 , wherein a molar ratio of the lamellar Li 2 MnO 3 in the cobalt-free and nickel-free positive electrode material is 50-90%.

18 . A battery, comprising a positive electrode, a negative electrode, and a separator, wherein the cobalt-free and nickel-free positive electrode material is used in the positive electrode.

19 . The battery according to claim 18 , wherein the cobalt-free and nickel-free positive electrode material comprises lamellar LiMnO 3 , spinel LiMn 2 O 4 , and lamellar Li 2 MnO 3 .

20 . The battery according to claim 19 , wherein a molar ratio of the lamellar Li 2 MnO 3 in the cobalt-free and nickel-free positive electrode material is 50-90%.

Assignees

• Svolt Energy Tech Co Ltd

Inventors

• Wang Pengfei
• Yang Hongxin
• Li Zitan
• Qiao Qiqi
• Shi Zetao
• Guo Feng
• Xu Xinpei

Classifications

• C01G45/125

  of the type (MnO3)n-, e.g. CaMnO3 · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2004/80

  Particles consisting of a mixture of two or more inorganic phases · CPC title