A kind of lithium ion battery negative electrode active material and preparation method, negative electrode and lithium ion battery

A negative electrode active material and lithium-ion battery technology, applied in battery electrodes, nanotechnology for materials and surface science, secondary batteries, etc., can solve the problems of poor battery cycle performance and large differences in conductivity of silicon-carbon materials, etc. Achieve better capacity, high first discharge efficiency, and good cycle performance

Active Publication Date: 2018-04-20
BYD CO LTD
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The present invention aims to solve the technical problem that the electrical conductivity of the silicon-carbon material and the electrical conductivity of graphite are greatly different from those of the existing lithium-ion battery negative electrode active materials, thereby resulting in poor battery cycle performance, and provides a negative electrode active material with stable conductivity and its Preparation method and negative electrode containing the negative electrode active material, while providing a lithium-ion battery with good cycle performance

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
  • A kind of lithium ion battery negative electrode active material and preparation method, negative electrode and lithium ion battery
  • A kind of lithium ion battery negative electrode active material and preparation method, negative electrode and lithium ion battery
  • A kind of lithium ion battery negative electrode active material and preparation method, negative electrode and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0038] The present invention has no special requirements for the preparation method of the negative electrode of the lithium ion battery, and can be carried out with reference to the prior art. For example, the preparation method of the negative electrode provided by the present invention generally includes coating and / or filling the negative electrode slurry on the negative electrode conductive matrix On, dry, calendered or not.

[0039] The negative electrode conductive substrate can be a conventional negative electrode conductive substrate in a lithium ion battery, such as punched metal, metal foil, mesh metal, foam metal, copper foil is used as the negative electrode conductive substrate in a specific embodiment of the present invention.

[0040] The methods and conditions of coating and / or filling, drying and calendering are well known to those skilled in the art. For example, the drying temperature is generally 100-150°C.

[0041] The present invention also provides a l...

Embodiment 1

[0053] Mix 1g of silicon with a particle size of 30nm and 10ml of diethylene glycol, then high-energy ball mill at a speed of 1000 rpm for 90 minutes to obtain A1; 10g of flat natural graphite at a speed of 1500 rpm for high-energy ball milling for 90 minutes Obtain flake graphite; then add the flake graphite into A1 and continue high-energy ball milling for 90 minutes at a rotational speed of 1500 rpm. Then under the protection of high-purity Ar, the temperature was raised to 950°C at a heating rate of 10°C / min, and calcined at 950°C for 5 hours to obtain product B1, which was crushed, treated with 3% HF for 20 minutes, and then washed with water until The pH value is 6, after drying, mix with 0.2g of high-temperature pitch (40), add 20g of naphthalene: stir at 80°C for 60 minutes, then put the stirred product under the protection of high-purity Ar, and increase the temperature to 10°C The temperature was raised to 1000° C. at a heating rate of 1 / min, and then calcined for 3 ...

Embodiment 2

[0055] Mix 2g of silicon with a particle size of 100nm and 10ml of diethylene glycol, and then high-energy ball mill at a speed of 2000 rpm for 60 minutes to obtain A2; 10g of Betray 918 graphite is high-energy ball milled at a speed of 2000 rpm 30min to obtain flake graphite; then add the flake graphite to A2 and continue high-energy ball milling at a speed of 1500 rpm for 90min. then 5%H 2 Under the protection of / Ar mixed gas, the temperature was raised to 600°C at a heating rate of 20°C / min, and calcined at 600°C for 3 hours to obtain product B2, which was crushed, treated with 15% NaOH aqueous solution for 30min, and then washed to pH The value is 8, and after drying, mix with 6g phenolic resin and stir at 60°C for 90 minutes, then put the stirred product in 5%H 2 Under the protection of / Ar mixed gas, the temperature was raised to 950° C. at a heating rate of 20° C. / min, and then calcined for 5 hours to obtain the negative electrode active material S2.

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
Login to view more

Abstract

The invention provides an active material comprising a first silicon carbon material and carbon covering the first silicon carbon material. The first silicon carbon material comprises flake graphite and a second silicon carbon material covering the flake graphite. The second silicon carbon material comprises nanometer silicon powder and amorphous carbon on the surface of the nanometer silicon powder. The mass ratio of the first silicon carbon material to the carbon covering the first silicon carbon material is 1:0.01-0.3. The invention also provides a preparing method of the active material, an anode containing the active material, and a lithium ion battery comprising the anode. The nanometer silicon of the anode active material is uniformly dispersed in the graphite and integrates with the flake graphite, so that conductivity is consistent. The lithium ion battery prepared by the anode active material is good in charge discharge efficiency, capacity retention ratio and coulombic efficiency.

Description

technical field [0001] The invention belongs to the field of lithium-ion batteries, and in particular relates to a lithium-ion battery negative electrode active material, a preparation method, a negative electrode and a lithium-ion battery. Background technique [0002] Lithium-ion batteries have been widely researched and applied due to their high working voltage, high energy density, good safety, light weight, and no pollution. Due to the low theoretical specific capacity of carbon materials generally used as negative electrode materials, which is only 372mAh / g, the development space is very limited, so the development of new negative electrode materials is very necessary. The use of silicon as a lithium-ion battery material, with a theoretical reversible capacity of 4400mAh / g, has attracted people's attention. However, studies have found that when silicon powder is used as the negative electrode material, the volume of the particles changes greatly during the charge and ...

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 Patents(China)
IPC IPC(8): H01M4/36H01M4/38H01M4/587H01M10/0525B82Y30/00
CPCB82Y30/00H01M4/366H01M4/38H01M4/587H01M4/625H01M10/0525Y02E60/10
Inventor 江正福
Owner BYD 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