Negative electrode active material, preparation method thereof, and lithium ion battery

A technology of negative electrode active materials and outer layer materials, applied in battery electrodes, secondary batteries, circuits, etc., can solve the problems of poor cycle performance and rate performance of negative electrode active materials, improve dispersion uniformity and conductivity, and avoid swelling Effect, environmental friendliness and pollution-free effect

Active Publication Date: 2016-02-17
DINGYUAN NEW ENERGY TECH CO LTD
View PDF8 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a negative active material for the poor cycle performance and rate performance of the negative active material in the prior art.

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
  • Negative electrode active material, preparation method thereof, and lithium ion battery
  • Negative electrode active material, preparation method thereof, and lithium ion battery
  • Negative electrode active material, preparation method thereof, and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0034] The present invention also provides a preparation method of the above-mentioned negative electrode active material, comprising the following steps:

[0035] S1. Provide a dispersion liquid containing silicon particles and a dispersion solvent;

[0036] S2, mixing multilayer graphene oxide with the dispersion liquid, then performing ultrasonic intercalation treatment, filtering and drying to obtain the first precursor;

[0037] Then subjecting the first precursor to a thermal reduction treatment in a non-oxidizing atmosphere, and cooling to obtain a second precursor;

[0038] S3. Mechanically modifying the second precursor to obtain an inner layer material; the inner layer material includes multi-layer graphene and silicon particles; the multi-layer graphene has a plurality of stacked sheets, corresponding to The spacing between adjacent sheets is 20-500nm;

[0039] S4. Forming a carbon layer on the surface of the inner layer material to obtain the outer layer material...

Embodiment 1

[0105] This example is used to illustrate the negative electrode active material disclosed in the present invention and its preparation method.

[0106] (1) Preparation of dispersion

[0107] Disperse 3g of nano-silicon particles (with a median diameter of 50nm) into a mixture of 45ml of absolute ethanol and 5ml of deionized water, ultrasonically disperse for 1h, then heat at 50°C in a nitrogen atmosphere, and add 0.3 g of γ-methacryloxypropyltrimethoxysilane was reacted for 24 hours to obtain a dispersion liquid comprising nano-silicon particles modified by γ-methacryloxypropyltrimethoxysilane.

[0108] (2) Preparation of the second precursor

[0109] First, prepare multilayer graphene oxide: by the improved Staudenmaier method, add 36ml of concentrated sulfuric acid and 18ml of concentrated nitric acid into a round bottom flask, add 2g of natural flake graphite under ice bath and magnetic stirring, and slowly Add 22g of potassium chlorate, and absorb the chlorine gas produ...

Embodiment 2

[0118] This example is used to illustrate the negative electrode active material disclosed in the present invention and its preparation method.

[0119] (1) Preparation of the first precursor

[0120] Disperse 3g of nano-silicon particles (with a median diameter of 50nm) into a mixture of 45ml of absolute ethanol and 5ml of deionized water, ultrasonically disperse for 1h, then heat at 50°C in a nitrogen atmosphere, and add 0.3 g of γ-methacryloxypropyltrimethoxysilane was reacted for 24 hours to obtain a dispersion liquid comprising nano-silicon particles modified by γ-methacryloxypropyltrimethoxysilane.

[0121] (2) Preparation of the second precursor

[0122] First, prepare multilayer graphene oxide: by the improved Staudenmaier method, add 36ml of concentrated sulfuric acid and 18ml of concentrated nitric acid into a round bottom flask, add 2g of natural flake graphite under ice bath and magnetic stirring, and slowly Add 22g of potassium chlorate, and absorb the chlorine ...

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 sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
specific surface areaaaaaaaaaaa
Login to view more

Abstract

The invention provides a negative electrode active material to solve the problems of poor cycle performances and poor rate performance of negative electrode active materials in the prior art. The negative electrode active material comprises an inner layer material and an outer layer material covered on the surface of the inner layer material; the inner layer material comprises multilayer graphene and silicon particles, a plurality of superposed lamellae are arranged in the multilayer graphene, and a spacing between adjacent lamellae is 20-500nm; the silicon particles are positioned among the lamellae in the multilayer graphene; and the outer layer material is a carbon layer. The invention also discloses a preparation method of the negative electrode active material, and a lithium ion battery. The negative electrode active material has the advantages of high conductivity, high capacity, low expansion, excellent cycle performances and excellent rate performance.

Description

technical field [0001] The invention relates to a negative electrode active material, a preparation method thereof, and a lithium ion battery. Background technique [0002] Lithium-ion batteries have been widely used in portable mobile electronic devices and electric vehicles due to their advantages such as large specific energy, high working voltage, long cycle life, no memory effect, small self-discharge, no pollution and environmental protection. At present, commercial lithium-ion batteries mainly use graphite-based negative electrode materials, but its theoretical specific capacity is only 372mAh / g, which cannot meet the demand for high energy density of lithium-ion batteries in the future. Domestic and foreign research reports, metal elements, metal oxides and metal alloy compounds that can form alloys with lithium, such as Si, Sn, Ge, Sb, Pb, SiO, SnO, SbSn, Mg 2 Si, etc., have a higher specific capacity. However, the battery capacity of these materials decays rapidl...

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): H01M4/36H01M4/583H01M10/0525
CPCH01M4/366H01M4/583H01M10/0525Y02E60/10
Inventor 李胜何鹏张长安
Owner DINGYUAN NEW ENERGY TECH CO LTD
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap