Preparation method of nickel lithium manganate coated lithium manganate positive electrode material

Abstract

The invention relates to the technical field of lithium batteries, in particular to a preparation method of a lithium nickel manganese oxide coated lithium manganate positive electrode material. The surface of the lithium manganate is coated with a layer of lithium nickel manganate, so that the conductivity of the lithium manganate can be effectively improved, and the charge-discharge performance of the lithium battery is further improved. Meanwhile, the preparation method is simple and easy to implement, low in cost and suitable for large-scale production. The lithium battery is wide in application range and can be applied to various fields needing lithium batteries, such as electronic products, electric automobiles, energy storage systems and the like. The nickel lithium manganate coated lithium manganate positive electrode material prepared by the invention can obviously improve the performance of a lithium battery and prolong the service life of the lithium battery, and has very high practical value and social benefit.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to a method for preparing a positive electrode material of lithium nickel manganese oxide coated with lithium manganese oxide. Background Art

[0002] Lithium manganese oxide is a common positive electrode material for lithium batteries, but its performance in practical applications is limited due to its low electrical conductivity. Therefore, how to improve the electrical conductivity of lithium manganese oxide has become the focus of current research. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing a positive electrode material of lithium nickel manganese oxide coated with lithium manganese oxide, which can effectively improve the conductivity of lithium manganese oxide, thereby improving the charge and discharge performance of lithium batteries.

[0004] The present invention is achieved through the following technical solutions: A method for preparing a lithium nickel manganese oxide coated lithium manganese oxide positive electrode material comprises the following steps: (1) mixing lithium manganate powder with an organic solvent to obtain a lithium manganate suspension; (2) mixing lithium nickel manganese oxide powder with an organic solvent to obtain a lithium nickel manganese oxide suspension; (3) mixing the lithium manganese oxide suspension and the nickel lithium manganese oxide suspension to obtain a mixed suspension; (4) heating and stirring the mixed suspension to coat the surface of the lithium manganese oxide with the lithium nickel manganese oxide; (5) Drying the coated mixture to obtain a lithium nickel manganese oxide coated lithium manganese oxide positive electrode material.

[0005] Compared with the prior art, the present invention has the following beneficial effects: By coating a layer of nickel lithium manganese oxide on the surface of lithium manganese oxide, the conductivity of lithium manganese oxide can be effectively improved, thereby improving the charge and discharge performance of lithium batteries. At the same time, the preparation method is simple and easy, low-cost, and suitable for large-scale production. DETAILED DESCRIPTION

[0006] The embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention.

[0007] Example 1 The purpose of the present invention is to provide a preparation method that can improve the conductivity of lithium manganese oxide positive electrode materials and thus improve the charge and discharge performance of lithium batteries. The method comprises the following steps: Prepare raw materials: Select appropriate amounts of lithium manganese oxide powder and nickel lithium manganese oxide powder as raw materials. These powders can be prepared by conventional methods.

[0008] Mixed suspension: lithium manganate powder is mixed with an organic solvent to obtain a lithium manganate suspension. The organic solvent can be a commonly used organic solvent such as alcohol, ketone or ester. Similarly, nickel lithium manganate powder is mixed with an organic solvent to obtain a nickel lithium manganate suspension.

[0009] Mixed suspension: The lithium manganate suspension and the nickel lithium manganate suspension are mixed to obtain a mixed suspension. This step is to allow the nickel lithium manganate powder to fully contact the lithium manganate powder so that it can better adhere to the surface of the lithium manganate in the subsequent coating step.

[0010] Heating and stirring: The mixed suspension is heated and stirred to coat the surface of lithium manganese oxide with nickel lithium manganese oxide. The heating temperature can be adjusted according to actual needs, generally controlled between 80-150 degrees Celsius. The stirring speed also needs to be moderate to avoid overheating the mixture or generating too many impurities.

[0011] Drying: The coated mixture is dried to obtain a lithium nickel manganese oxide coated lithium manganese oxide positive electrode material. The drying temperature and time can be adjusted according to actual conditions to evaporate the moisture inside the material and ensure the quality of the coating layer.

[0012] The invention has the advantages that by coating a layer of nickel lithium manganese oxide on the surface of lithium manganese oxide, the conductivity of lithium manganese oxide can be effectively improved, thereby improving the charge and discharge performance of the lithium battery. At the same time, the preparation method is simple and easy, low in cost, and suitable for large-scale production.

[0013] The present invention has a wide range of applications and can be used in various fields that require the use of lithium batteries, such as electronic products, electric vehicles, energy storage systems, etc. By using the nickel manganese oxide coated lithium manganese oxide positive electrode material prepared by the present invention, the performance of the lithium battery can be significantly improved, and its service life can be extended, which has high practical value and social benefits.

Claims

1. A method for preparing a positive electrode material of lithium nickel manganese oxide coated with lithium manganese oxide, characterized in that: The following steps are involved: (1) mixing lithium manganate powder with an organic solvent to obtain a lithium manganate suspension; (2) mixing lithium nickel manganese oxide powder with an organic solvent to obtain a lithium nickel manganese oxide suspension; (3) mixing the lithium manganese oxide suspension and the nickel lithium manganese oxide suspension to obtain a mixed suspension; (4) heating and stirring the mixed suspension to coat the surface of the lithium manganese oxide with the lithium nickel manganese oxide; (5) Drying the coated mixture to obtain a lithium nickel manganese oxide coated lithium manganese oxide positive electrode material.

2. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: Prepare raw materials: Select appropriate amounts of lithium manganese oxide powder and nickel lithium manganese oxide powder as raw materials. These powders can be prepared by conventional methods.

3. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: The organic solvent may be a commonly used organic solvent such as alcohol, ketone or ester.

4. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: Mixed suspension: Mix the lithium manganate suspension and the nickel lithium manganate suspension to obtain a mixed suspension.

5. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: Heating and stirring: The mixed suspension is heated and stirred to coat the surface of the lithium manganese oxide with the nickel lithium manganese oxide.

6. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: The heating temperature can be adjusted according to actual needs and is generally controlled between 80-150 degrees Celsius.

7. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: The stirring speed also needs to be moderate to avoid overheating the mixture or creating too many impurities.

8. The method for preparing the lithium nickel manganese oxide coated lithium manganese oxide positive electrode material according to claim 1, characterized in that: Drying: Drying the coated mixture to obtain a lithium nickel manganese oxide coated lithium manganese oxide positive electrode material.