Unlock instant, AI-driven research and patent intelligence for your innovation.

Positive electrode material and preparation method and application thereof

A cathode material and matrix technology, which is applied in the field of cathode materials and their preparation, can solve the problems of reduced material cycle performance and crystal structure damage, and achieves the effects of low production cost, improved energy density, and improved stability.

Pending Publication Date: 2021-12-07
BYD CO LTD
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the problems of chemical delithiation, crystal structure damage, and material cycle performance reduction in lithium-ion battery cathode materials in the prior art after removal of residual lithium on the surface, and to provide a cathode material and its preparation method and application. The positive electrode material effectively utilizes the residual lithium on the surface, improves the stability and cycle performance of the positive electrode material, has simple process, low production cost, and is easy for industrial production

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Positive electrode material and preparation method and application thereof
  • Positive electrode material and preparation method and application thereof
  • Positive electrode material and preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment approach

[0031] According to a preferred embodiment of the present invention, the matrix is ​​selected from LiNi 0.8 co 0.15 al 0.05 o 2 、LiNi 0.8 co 0.1 mn 0.1 o 2 、LiNi 0.6 co 0.2 mn 0.2 o 2 、LiNi 0.4 co 0.3 mn 0.3 o 2 、LiNi 0.7 co 0.3 o 2 、LiNi 0.6 mn 0.4 o 2 、LiNi 0.9 co 0.05 al 0.05 o 2 and LiCoO 2 At least one of them, the present invention is not limited to this, as long as the above general formula is satisfied.

[0032] According to the present invention, preferably, the particle size D50 of the matrix is ​​0.5-40 μm, preferably 2-20 μm, wherein the particle size of the matrix is ​​measured by a laser diffraction method.

[0033] In the present invention, the selection of the particle size of the matrix is ​​mainly based on the comprehensive consideration of the specific surface area of ​​the material and the rate performance of the material. The material with a relatively small particle size of the matrix has a large specific surface area, which may c...

Embodiment 1

[0069] (1) Ni with a particle size of 10 μm 0.8 co 0.1 mn 0.1 (OH) 2 with LiOH·H 2 After O was mixed at a molar ratio of 1:1.05, the first sintering was carried out in an oxygen atmosphere to obtain a matrix, wherein the conditions of the first sintering included: first roasting at 450°C for 3 hours, and then roasting at 780°C for 15 hours;

[0070] (2) the matrix in CO 2 The second sintering is carried out in the air to obtain the positive electrode material P1, wherein the second sintering conditions include: sintering at 200° C. for 2 hours.

[0071] Wherein, the TEM image of the positive electrode material P1 is as follows figure 1 said, by figure 1 It can be seen that the TEM image of the positive electrode material P1 is the matrix (dark color) and the coating layer (light color) from the lower right corner to the upper left corner, that is, the positive electrode material P1 has a core-shell structure.

[0072] Wherein, the XRD pattern of the positive electrode m...

Embodiment 2

[0074] (1) Ni with a particle size of 10 μm 0.8 co 0.1 mn 0.1 (OH) 2 with LiOH·H 2 After O was mixed at a molar ratio of 1:1.05, the first sintering was carried out in an oxygen atmosphere to obtain a matrix, wherein the conditions of the first sintering included: first roasting at 450°C for 3 hours, and then roasting at 780°C for 15 hours;

[0075] (2) the matrix in CO 2 The second sintering is carried out in a mixed gas of CO and air, where CO 2 The content is 20% by volume to obtain the positive electrode material P2, wherein the second sintering condition includes: sintering at 200° C. for 6 hours.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
thicknessaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to View More

Abstract

The invention relates to the technical field of lithium ion batteries, in particular to a positive electrode material and a preparation method and application thereof.The positive electrode material comprises a matrix and a coating layer on the surface of the matrix, the matrix is a compound shown in the general formula LiNi<x>Co<y>Mn<1-x-y-z>M O<2>, M is a doped metal element, x is greater than or equal to 0 and less than or equal to 1, y is greater than or equal to 0 and less than or equal to 1, z is greater than or equal to 0 and less than or equal to 0.2, x + y + z is greater than or equal to 0 and less than or equal to 1, and x, y and z are not 0 at the same time; and the coating layer is Li2CO3 (lithium carbonate). According to the positive electrode material provided by the invention, residual Li2O on the surface of the matrix is converted into Li2CO3, so that the stability of the material in the air is improved, and when Li+ generated by decomposition of Li2CO3 is diffused to a negative electrode, the energy density of the whole battery is improved, so the cycle performance of the battery is improved. Meanwhile, the positive electrode material provided by the invention is simple in preparation method, relatively low in production cost and easy for large-scale industrial production.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a positive electrode material and a preparation method and application thereof. Background technique [0002] With the rapid development of new energy vehicles, the market's requirements for the energy density and life of power lithium-ion batteries are increasing. As an important part of the lithium-ion battery system, cathode materials with high energy density and long cycle life are facing huge market demand. With α-NaFeO 2 Nickel-rich ternary material LiNi with layered structure x co y mn 1-x-y o 2 (x≥0.8) combined with LiNiO 2 、LiCoO 2 and LiMnO 2 The characteristics of the three cathode materials, which simultaneously have the advantages of high energy density, long cycle life, and high safety, have attracted extensive attention from researchers. [0003] However, there are still some problems with high-nickel cathode materials, which limit their larg...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): H01M4/36H01M4/485H01M4/505H01M4/525H01M4/62H01M10/0525
CPCH01M4/366H01M4/485H01M4/505H01M4/525H01M4/62H01M10/0525Y02E60/10
Inventor 韩晓燕焦晓朋李世彩
Owner BYD CO LTD