CN110871135B

CN110871135B - Method for classifying and separating electrode materials with micro-size

Info

Publication number: CN110871135B
Application number: CN201911101661.2A
Authority: CN
Inventors: 崔大祥; 阳靖峰; 张芳; 卢玉英; 张道明; 王亚坤; 焦靖华; 张放为
Original assignee: Shanghai National Engineering Research Center for Nanotechnology Co Ltd
Current assignee: Shanghai National Engineering Research Center for Nanotechnology Co Ltd
Priority date: 2019-11-12
Filing date: 2019-11-12
Publication date: 2021-07-20
Anticipated expiration: 2039-11-12
Also published as: CN110871135A

Abstract

The invention discloses a method for classifying and separating a fine-size electrode material. The method comprises the steps of carrying out coarse grinding and screening on coarse powder of an electrode raw material by using a vertical mill, preparing slurry, carrying out classification separation by using a hydrocyclone, and finally selecting and collecting to obtain a fine-size material meeting the size requirement. The invention effectively separates fine-size particle materials and coarse-size particle materials, ensures the quality of raw materials, greatly reduces the production cost and the production time, and obviously improves the production efficiency compared with the traditional vacuum or pressure filtration method. The method has the advantages of convenient operation, low cost and low energy consumption, and effectively prepares the electrode material of the fine-sized particles which meets the size requirement.

Description

Method for classifying and separating electrode materials with micro-size

Technical Field

The invention relates to the field of battery electrode material preparation, in particular to a fine-size electrode material grading separation method, and belongs to a method for screening and selecting electrode materials.

Background

Lithium ion batteries are now widely used in many areas and industries of society, such as automobiles, portable devices, telecommunication base stations, and the like. At present, the capacity of the lithium ion battery becomes the biggest bottleneck meeting the development requirements of human society, a novel electrode material is searched and developed, and the capacity of the battery is urgently improved. The novel electrode material such as silicon and sub-silicon has the characteristic of large capacity, but because the novel electrode material has a volume effect and has requirements on the size of material particles, the performance of the ultra-fine particle electrode material is optimal. Therefore, the electrode material needs to be screened and separated during the preparation process so as to obtain a product with a desired size.

Disclosure of Invention

Aiming at the problems that the granularity of the current battery electrode material is required to reach 5 microns or less, and fine particles with target sizes are difficult to obtain by adopting common vacuum or pressure filtration, the invention aims to provide a fine size electrode material fractionation method. The method has the characteristics of convenience and rapidness in operation, low cost and low energy consumption, and can obtain electrode materials meeting different size requirements.

The purpose of the invention is realized by the following technical scheme: a fine size electrode material grading separation method is characterized in that a vertical mill is used for carrying out coarse grinding and screening on coarse powder of an electrode raw material, then the coarse powder is prepared into slurry, the slurry is subjected to grading separation through a hydrocyclone, and finally fine selection and collection are carried out to obtain a fine size material meeting size requirements, and the method comprises the following steps:

(1) coarsely grinding the electrode material raw material by using a vertical mill until the particle size is 1-150 microns;

(2) mixing the coarsely ground and pulverized material with a solvent to enable the mass percentage of the material in the slurry to be 10-30% and preparing slurry;

(3) the slurry is subjected to classification separation through a hydrocyclone;

(4) collecting the separated electrode particles with the micro size, thereby obtaining a target product.

Wherein, the solvent in the step (2) is water or alcohol.

In the step (3), the hydrocyclone fractionation process comprises three times of stage-by-stage separation, particles below 100 microns are separated in an overflow liquid mode for the first time, and the separated particles D50 are smaller than 100 microns; separating particles with particle size below 50 microns in the overflow liquid separated from the overflow liquid for the second time, wherein the separated particles D50 is less than 50 microns; and thirdly, separating particles with the particle size of less than 5 microns in the overflow liquid separated in the second time, wherein the separated particles D50 is less than 5 microns.

In the invention, the outlet of the vertical mill is connected with a slurry preparation container, and the slurry preparation container is connected with a hydrocyclone.

The invention has the following advantages: fine-size particle materials and coarse-size particle materials are effectively separated, and the quality of the electrode material is ensured; greatly reducing the production cost and the production time; compared with the traditional vacuum or pressure filtration method, the production efficiency is obviously improved; convenient operation, low cost and low energy consumption.

Drawings

FIG. 1 is a schematic view of a process for classifying a fine-sized electrode material according to the present invention.

Detailed Description

Example 1

A fine size electrode material grading separation method, utilize the vertical mill to carry on the coarse grinding screening to the raw material coarse powder of electrode, then make into the slurry liquid and pass the hydrocyclone grading separation, finally carefully select collect get accord with fine size material that size require, as shown in figure 1 fine size electrode material grading process schematic diagram of the invention, according to the following steps:

a) feeding the electrode material raw material into a vertical mill, and carrying out coarse grinding and crushing on the electrode material raw material, wherein the particle size D50 of the raw material subjected to coarse grinding is 100 micrometers;

b) mixing the coarsely ground and pulverized material with water according to a mass ratio of 15: 85, namely preparing the slurry by mixing the materials in the slurry according to the mass percentage of 15%;

c) feeding the slurry into a hydrocyclone through a slurry pump to carry out three times of separation respectively;

d) and collecting the final product after three times of separation, thereby obtaining the fine-size material meeting the requirement.

Wherein, the hydrocyclone separation process comprises three times of step-by-step separation, the first time separates the particles below 100 microns in an overflow liquid mode, and the separated particles D50 are less than 100 microns; separating particles with particle size below 50 microns in the overflow liquid separated from the overflow liquid for the second time, wherein the separated particles D50 is less than 50 microns; and thirdly, separating particles with the particle size of less than 5 microns in the overflow liquid separated in the second time, wherein the separated particles D50 is less than 5 microns. And (4) respectively collecting.

Example 2

The method for separating the electrode material with the micro size comprises the following steps, similar to the embodiment:

a) the raw material of the electrode material was subjected to coarse grinding and pulverization in a vertical mill, and the particle size D50 of the coarse ground raw material was 80 μm.

b) Mixing the coarsely ground and pulverized material with water according to the mass ratio of 20: 80 (i.e., 20% by weight of the material in the slurry) to form a slurry.

c) The slurry is pumped into a hydrocyclone by a slurry pump to be separated for three times respectively.

Example 3

a) the electrode material raw material was subjected to coarse grinding and pulverization in a vertical mill, and the particle size D50 of the coarse ground raw material was 50 μm.

b) Mixing the coarsely ground and pulverized material with water according to a mass ratio of 30: 70 percent (i.e., 30 percent by weight of material in the slurry) to form a slurry.

The above examples are merely illustrative for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.

Claims

1. A method for grading and separating electrode materials with fine size is characterized in that a vertical mill is used for carrying out coarse grinding and screening on the raw materials of the electrode materials, then the raw materials are prepared into slurry, the slurry is subjected to grading separation through a hydrocyclone, and finally, fine selection and collection are carried out to obtain the materials with the fine size meeting the size requirement, and the method comprises the following steps:

(2) mixing the coarsely ground and pulverized material with a solvent to enable the mass percentage of the material in the slurry to be 10-30% and preparing the slurry;

(4) collecting the separated electrode particles with the micro size so as to obtain a target product; wherein the content of the first and second substances,

the hydrocyclone separation process in the step (3) comprises three times of step-by-step separation, particles below 100 microns are separated in an overflow liquid mode for the first time, and the separated particles D50 are smaller than 100 microns; separating particles with particle size below 50 microns in the overflow liquid separated from the overflow liquid for the second time, wherein the separated particles D50 is less than 50 microns; and thirdly, separating particles with the particle size of less than 5 microns in the overflow liquid separated in the second time, wherein the separated particles D50 is less than 5 microns.

2. The method for fractionating a fine-sized electrode material according to claim 1, wherein the solvent in the step (2) is water or alcohol.

3. The method for classifying a fine-sized electrode material according to claim 1, wherein the outlet of the vertical mill is connected to a slurry preparation vessel, and the slurry preparation vessel is further connected to a hydrocyclone.