Lithium ion battery negative electrode comprising diamond-like thin film layer, preparation method for negative electrode, and lithium ion battery

A diamond film, lithium-ion battery technology, applied in battery electrodes, secondary batteries, circuits, etc., can solve the problems of low chemical stability, inability to maintain structure, poor mechanical properties, etc., to prevent the formation of unstable SEI layers , good cycle stability, and the effect of being conducive to large-scale production

Inactive Publication Date: 2017-05-17
SHENZHEN INST OF ADVANCED TECH
View PDF3 Cites 40 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these materials still cannot maintain a very stable structure during the charge-discharge cycle, which is of limited help to improve the cycle stability of the negative electrode, because the above-mentioned carbon layer is mainly composed of amorphous carbon and sp2 phase, and hardly contains diamond phase. Poor performance, low chemical stability, always showing low conductivity, a large number of dangling bonds can also cause chemical and electrochemical reactions with the electrolyte

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
  • Lithium ion battery negative electrode comprising diamond-like thin film layer, preparation method for negative electrode, and lithium ion battery
  • Lithium ion battery negative electrode comprising diamond-like thin film layer, preparation method for negative electrode, and lithium ion battery
  • Lithium ion battery negative electrode comprising diamond-like thin film layer, preparation method for negative electrode, and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] A preparation method of a lithium-ion battery negative electrode containing a diamond-like film layer, comprising the following steps:

[0037] (1) Take a single crystal silicon wafer, the resistivity is lower than 5mΩ﹒ cm, add a mixed aqueous solution of silver nitrate and hydrofluoric acid (where the concentration of silver nitrate is 0.005M and the concentration of hydrofluoric acid is 4.8M) in a polytetrafluoroethylene container, immerse the silicon chip in the solution for 1 minute, and then The silicon chip is taken out and placed in a mixed solution of hydrofluoric acid and hydrogen peroxide (the concentration of hydrofluoric acid is 4.8M and the concentration of hydrogen peroxide is 0.3M) and kept for 30 minutes. After taking out, the silicon chip is rinsed with water and immersed in a nitric acid solution diluted with water ( 1:1 v / v) to remove the silver catalyst, followed by drying at 60°C. The silicon nanowires are separated from the single crystal silicon ...

Embodiment 2

[0048] A preparation method of a lithium-ion battery negative electrode containing a diamond-like film layer, comprising the following steps:

[0049] (1) According to the ratio of silicon powder: acetylene black: carboxymethylcellulose (CMC) mass ratio of 8:1:1, the three are evenly dispersed in N-methylpyrrolidone (NMP), and evenly mixed in a mortar Mix to form a uniformly dispersed slurry, and evenly coat the resulting slurry on a clean metal copper foil, then dry it in a vacuum oven at 80°C for 24 hours, and then take out the coated copper foil and pass it through a roller press After rolling, press it into a disc with a 12mm tablet press to obtain a copper foil with a negative electrode active material layer;

[0050] (2) ECR-MPCVD is used to deposit and prepare a nitrogen-doped n-type conductive diamond-like film layer on the surface of the negative electrode active material layer. During the deposition process, feed methane as a carbon source, nitrogen as a doping gas, ...

Embodiment 3

[0052] A preparation method of a lithium-ion battery negative electrode containing a diamond-like film layer, comprising the following steps:

[0053] (1) According to the ratio of tin-based negative electrode material: acetylene black: carboxymethylcellulose (CMC) mass ratio of 8:1:1, the three are evenly dispersed in NMP, and uniformly mixed in a mortar to form a dispersion Uniform slurry, evenly coat the obtained slurry on a clean metal copper foil, and then dry it in a vacuum oven at 80°C for 24 hours, then take out the coated copper foil and press it with a roller press, Press into a disc with a 12mm tablet press to obtain a copper foil with a negative electrode active material layer;

[0054] (2) Using DC magnetron sputtering to deposit a boron-doped diamond-like carbon film layer on the surface of the negative electrode active material layer, the deposition process is: feed argon into the vacuum chamber and open the composite target, the composite target is carbon Boro...

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a lithium ion battery negative electrode comprising a diamond-like thin film layer. The negative electrode comprises a conductive current collector, a negative electrode active material layer arranged on the conductive current collector and a diamond-like thin film layer deposited on the surface of the negative electrode active material layer; and the diamond-like thin film layer comprises doped elements, wherein the doped elements comprises one or more of Si, B, N, P, Al, Be, Mg, Ti, Cr, W, Fe, Zr, Pt, Mo, Co, Ni and Sb. According to the lithium ion battery negative electrode, the diamond-like thin film layer is deposited on the surface of the negative electrode active material layer, and the diamond-like thin film layer has excellent electrochemical inertness and conductivity and high mechanical strength, so that occurrence of an unstable SEI layer on the surface of the negative electrode active material is avoided, and the cycling stability of the electrode is greatly improved. The invention also provides a preparation method for the lithium ion battery negative electrode, and the lithium ion battery.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a lithium ion battery negative electrode, a preparation method thereof and a lithium ion battery. Background technique [0002] The development of high-performance electrodes is the key to improving the performance of lithium-ion batteries, and it is also a hot and difficult point in current research. Anode materials play a key role in the performance of lithium batteries, especially in terms of capacity and lifetime. New anode materials such as silicon, germanium, tin, transition metal oxides, and metal nitrides all exhibit high anode capacity and good electrochemical performance. However, these materials generally have the problem of poor stability, which seriously restricts their industrialization process. In actual battery applications, as the number of cycles increases, the SEI film on the electrode surface will be destroyed due to continuous expansion and co...

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): H01M4/62H01M4/36H01M4/583H01M10/0525
CPCH01M4/366H01M4/583H01M4/625H01M10/0525Y02E60/10
Inventor 杨扬唐永炳张文军李振声
Owner SHENZHEN INST OF ADVANCED TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products