Silicon composite oxide for negative electrode material of lithium secondary battery and preparation method thereof

A composite oxide and lithium secondary battery technology, which is applied in the direction of secondary batteries, electrode manufacturing, battery electrodes, etc., can solve the problems of reduced capacity retention rate, reduced battery capacity, and reduced slurry stability, so as to improve capacity Effects of promotion rate, capacity improvement, and charge/discharge capacity improvement

Active Publication Date: 2021-07-09
DAEJOO ELECTRONICS MATERIALS CO LTD
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

There are some problems with such an irreversible reaction: leading to loss of lithium, the initial charge / discharge efficiency (ICE) drops below 75%, and when designing secondary batteries, excess cathode capacity is required, which in practical batteries would offset every High capacity per unit mass of negative electrode
Through this method, although the initial efficiency is improved, there are still some problems: the battery capacity is reduced, the stability of the slurry is reduced when making electrodes, and industrial production is difficult due to difficult handling
According to this method, the SiO x Powder and MgH 2 or CaH 2 The incorporation of oxygen decreases during the reaction, but the silicon crystal size grows rapidly due to the local exothermic reaction, Mg or Ca is not uniformly distributed, so compared to SiO x The capacity retention rate of

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
  • Silicon composite oxide for negative electrode material of lithium secondary battery and preparation method thereof
  • Silicon composite oxide for negative electrode material of lithium secondary battery and preparation method thereof
  • Silicon composite oxide for negative electrode material of lithium secondary battery and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0061] Preparation of Si-MgSiO 3 -SiO x -C-based silicon composite oxide

[0062] Step (1): Add 8kg of silicon powder with an average particle size of 20μm and 16kg of silicon dioxide powder with an average particle size of 20nm into 50kg of water, stir for 12 hours, mix well, and dry at 200°C for 24 hours to form a raw material Powder mix.

[0063] Step (2): Put 2kg of the raw material powder mixture and metal magnesium into crucible A and crucible B of the vacuum reactor respectively, depressurize to 0.1 torr, then heat, raise the temperature of crucible A to 1500°C, and the crucible B was heated to 900°C and reacted for 5 hours.

[0064] Step (3): The mass of silicon composite oxide deposited on the substrate inside the reactor through the reaction in the high-temperature gas phase is rapidly cooled to room temperature through the water-cooled substrate.

[0065] Step (4): In order to control the particle size, the silicon composite oxide block is mechanically crush...

experiment example

[0076] X-ray diffraction pattern analysis

[0077] In order to analyze the crystal structure of the silicon composite oxide prepared in the above-mentioned embodiment 1, its X-ray diffraction pattern was analyzed, and the results are shown in figure 2 .

[0078] Such as figure 2As can be seen in the X-ray diffraction pattern, the peak attributable to Si crystal appears around the diffraction angle (2θ) 28.5°, and the peak attributable to MgSiO appears near the diffraction angle (2θ) 31.0° 3 Crystal peak, thus it can be seen that the silicon composite oxide prepared in Example 1 of the present invention is composed of crystalline Si and MgSiO 3 composition.

[0079] In addition, if figure 2 As seen in the X-ray diffraction diagram of the silicon composite oxide, it can be known from the content of each element component in the silicon composite oxide that it also contains amorphous silicon oxide (SiO x ) and carbon.

[0080] The Si crystal size (crystal size) in the ...

Embodiment 2

[0083] Preparation of Si-MgSiO 3 -Mg 2 SiO 4 -SiOx-C silicon composite oxide

[0084] The silicon composite oxide powder was prepared by the same method as in the above-mentioned Example 1, except that the silicon composite oxide bulk deposited on the substrate in the above-mentioned Example 1 was naturally cooled with a substrate without water cooling.

[0085] Content analysis of component elements

[0086] The contents of magnesium, oxygen, and carbon in the silicon composite oxide prepared in the above-mentioned Example 2 were analyzed.

[0087] After analysis, the Mg content in the silicon composite oxide is 10wt%, which is analyzed by ICP emission spectrometry, and the content of O and C is 30wt% and 5wt%, which is analyzed by an elemental analyzer. In addition, the specific gravity is 2.6, which is analyzed by a powder pycnometer. After analysis, its value is greater than the specific gravity of SiO (2.2) and less than that of MgSiO 3 Specific gravity (2.7) ...

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
crystal sizeaaaaaaaaaa
thicknessaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to view more

Abstract

The present invention relates to a kind of silicon compound oxide and preparation method thereof for negative electrode material of lithium secondary battery, relate to a kind of by making Si / SiO 2 The raw material powder mixture and metal magnesium undergo a gas phase reaction, so that silicon oxide (SiO X , 0<x<2) contains silicon particles, MgSiO 3 (enstatite) and Mg 2 SiO 4 (Magnesium silicate) crystal, and the silicon composite oxide used for the negative electrode material of lithium secondary battery whose surface is coated with carbon and its preparation method.

Description

technical field [0001] The present invention relates to a kind of silicon compound oxide and preparation method thereof for negative electrode material of lithium secondary battery, relate to a kind of by making Si / SiO 2 The raw material powder mixture and metal magnesium undergo a gas phase reaction, so that silicon oxide (SiO X , 0<x<2) contains silicon particles, MgSiO 3 (enstatite) and Mg 2 SiO 4 (Magnesium silicate) crystal, and the silicon composite oxide used for the negative electrode material of lithium secondary battery whose surface is coated with carbon and its preparation method. Background technique [0002] As the demand for secondary batteries is emphasized in the miniaturization and high performance of mobile devices, electric vehicles, and large-capacity energy storage industries, there is an increasing demand for improved performance of lithium secondary batteries. In order to increase the energy density, research and development are currently un...

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): H01M4/13H01M4/131H01M4/36H01M4/48H01M10/0525
CPCH01M4/48H01M10/0525H01M4/366H01M4/5825H01M4/583H01M4/625H01M2004/027H01M4/1395H01M4/386H01M4/0428H01M4/1391H01M4/364H01M4/483H01M4/485Y02E60/10H01M4/131H01M4/134Y02P70/50
Inventor 吴性旻金壮翰金多恩
Owner DAEJOO ELECTRONICS MATERIALS 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