A silicon-based negative electrode material for a secondary battery, a method for preparing the same, and the secondary battery

A silicon-based negative electrode material and secondary battery technology, which is applied in secondary batteries, battery electrodes, electrode manufacturing, etc., can solve the problems of poor safety performance of lithium supplementation process, reduced electrode cycle life, and low initial Coulombic efficiency, etc., to achieve improved Effects of fast charging ability, enhanced electron mobility rate, and improved cycle performance

Active Publication Date: 2020-05-15
SHANGHAI SHANSHAN TECH CO LTD
View PDF4 Cites 27 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In the prior art, the lithium layer is usually directly coated on the surface of the electrode pole piece, or the process of electrochemically plating lithium on the surface of the electrode pole piece is used to supplement lithium. However, the lithium supplementation process will lead to Si on the one hand The grain growth is too large, which reduces the cycle life of the electrode. On the other hand, the safety performance of the lithium supplementation process is poor, and it is difficult to achieve mass production
Moreover, due to the formation of irreversible substances during the lithium intercalation process of silicon-oxygen materials, the first Coulombic efficiency is low, making it difficult for commercial applications.

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 silicon-based negative electrode material for a secondary battery, a method for preparing the same, and the secondary battery
  • A silicon-based negative electrode material for a secondary battery, a method for preparing the same, and the secondary battery
  • A silicon-based negative electrode material for a secondary battery, a method for preparing the same, and the secondary battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0056] Another aspect of the present application provides a method for preparing a silicon-based negative electrode material for a secondary battery, comprising:

[0057] Step S1, preparing a first mixture, said first mixture including silicon oxygen raw material SiOx, metal source material and carbon source material (wherein 0

[0058] Wherein, the silicon-oxygen raw material SiOx is a powder with a median particle diameter D50 of 1-10 μm, and the method for forming the silicon-oxygen raw material SiOx powder is, for example, to obtain SiOx powder by coarsely crushing and pulverizing bulk SiOx. The primary crushing includes using a jaw crusher, a pair of roller crushers, a cone crusher, a hammer crusher or an impact crusher to perform primary crushing on the massive SiOx. The crushing includes further crushing the coarsely crushed SiOx by using any one of a jet mill, a mechanical mill, a ball mill or a vibration mill, so as to obtain a powder with a median particle size...

Embodiment 1

[0075] The bulk SiOx (x=0.9) is coarsely crushed by a roller crusher, and the coarsely crushed raw material is pulverized by a jet mill to obtain a SiOx powder with a particle diameter D50 of 5 μm, and the SiOx powder is mixed with carbonic acid Lithium and citric acid are thoroughly mixed in a high-speed stirring mill to prepare a first mixture comprising lithium carbonate, citric acid and SiOx. Wherein, the quality of the silicon oxygen raw material SiOx is 1Kg, the quality of the lithium carbonate is 476.8g, and the quality of the citric acid is 5g.

[0076] The first mixture is calcined by a rotary kiln in an argon atmosphere, the calcination temperature is 750°C, and the reaction time is 12h, to obtain the inner core including SiOx 1 and Si particles, the first shell consists of Li 2 SiO 3 and the first product of the C particle.

[0077] The first product is passed through a pitch doped with conductive graphite for a coating reaction in a coating kettle. The coating r...

Embodiment 2

[0080] The bulk SiOx (x=0.9) is coarsely crushed by a roller crusher, and the coarsely crushed raw material is pulverized by a jet mill to obtain a SiOx powder with a particle diameter D50 of 5 μm, and the SiOx powder is mixed with carbonic acid Lithium and citric acid are thoroughly mixed in a high-speed stirring mill to prepare a first mixture comprising lithium carbonate, citric acid and SiOx. Wherein, the quality of the silicon oxygen raw material SiOx is 1Kg, the quality of the lithium citrate is 286.1g, and the quality of the citric acid is 5g.

[0081] The first mixture is calcined by a rotary kiln in an argon atmosphere, the calcination temperature is 750°C, and the reaction time is 12h, to obtain the inner core including SiOx 1 and Si particles, the first shell consists of Li 2 SiO 3 and the first product of the C particle.

[0082] The first product is coated with pitch doped with conductive graphite in a coating kettle, the coating reaction is carried out in an a...

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The present application provides a silicon-based negative electrode material for a secondary battery, a method for preparing the same, and a secondary battery; the silicon-based negative electrode material for a secondary battery comprising: an inner core comprising Si particles and a silicon oxide SiOx1, wherein 0<x1<2; the first shell layer that comprises a compound with a general formula of MySiOz (y is more than 0 and less than or equal to 4, z is more than 0 and less than or equal to 5, and z is more than or equal to x1) and C particles, the first shell layer covers the inner core, and the contents of M and C in the first shell layer are gradually increased from one side close to the inner core to one side far away from the inner core; and the second shell layer that comprises a carbon film layer or a composite film layer formed by the carbon film layer and a conductive additive, and the second shell layer wraps the first shell layer. The first charge-discharge cycle capability ofthe silicon-based negative electrode material is improved, and the manufacturing cost is reduced.

Description

technical field [0001] The invention relates to the field of secondary batteries, in particular to a silicon-based negative electrode material for secondary batteries, a preparation method thereof, and a secondary battery. Background technique [0002] The negative electrode material of traditional lithium-ion batteries is graphite. However, the theoretical capacity of graphite is only 372mAh / g, which cannot meet the high energy demand of lithium-ion batteries in the current industry. Silicon is abundant in nature, and it is safe and environmentally friendly, which has attracted more and more attention from researchers. Moreover, in theory, silicon has a high capacity, its capacity can reach 4200mAh / g, its discharge potential is relatively low, its price is low, and it is environmentally friendly. It is an excellent negative electrode material for lithium-ion batteries. However, due to the serious volume effect of silicon-based materials, the cycle performance of silicon-ba...

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): H01M4/36H01M4/38H01M4/48H01M4/58H01M4/62H01M10/0525
CPCH01M4/366H01M4/386H01M4/48H01M4/625H01M4/5825H01M10/0525Y02E60/10H01M4/36H01M4/364H01M4/134H01M4/483H01M4/485H01M4/38H01M4/1395H01M4/62H01M4/58H01M4/587H01M4/131H01M2004/027H01M4/0471
Inventor 吴玉虎马飞刘冬冬魏良勤吴志红丁晓阳李凤凤
Owner SHANGHAI SHANSHAN 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