Nanometer sheet-shaped silicon-carbon composite material used as lithium ion battery negative electrode material and preparation method of nanometer sheet-shaped silicon-carbon composite material

A technology of silicon-carbon composite materials and lithium-ion batteries, applied in nanotechnology for materials and surface science, battery electrodes, carbon preparation/purification, etc., can solve problems such as few reports on nano-silicon/carbon composite materials, Achieve the effect of improving charge transfer efficiency, controllable conditions, and improving performance

Active Publication Date: 2022-04-12
HEFEI UNIV OF TECH
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the magnesia thermal reduction method is mostly used to prepare pure-phase nano-silicon anode materials, and there are few reports on the preparation of nano-silicon / carbon composite materials directly based on the magnesia thermal reaction of cage silsesquioxanes.

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
  • Nanometer sheet-shaped silicon-carbon composite material used as lithium ion battery negative electrode material and preparation method of nanometer sheet-shaped silicon-carbon composite material
  • Nanometer sheet-shaped silicon-carbon composite material used as lithium ion battery negative electrode material and preparation method of nanometer sheet-shaped silicon-carbon composite material
  • Nanometer sheet-shaped silicon-carbon composite material used as lithium ion battery negative electrode material and preparation method of nanometer sheet-shaped silicon-carbon composite material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] In this embodiment, nano-sheet silicon-carbon composites are prepared according to the following steps:

[0037] (1) Preparation of precursor powder

[0038] Weigh 0.5 g of vinyl cage octahedral silsesquioxane, 4.5 g of lithium chloride and 5.5 g of potassium chloride and grind them in a mortar for 10 min, and mix the ground powder in a ball mill at 500 rpm for 2 h. The ball-milled mixture was dried at 70° C. for 4 h to obtain the precursor powder.

[0039] (2) High temperature magnesia thermal reduction

[0040] Put the precursor powder on one end of the stainless steel burning boat, add 0.5g magnesium powder to the other end, and transfer the burning boat to the tube furnace. Then, the temperature was raised to 400° C. at a rate of 5° C. / min under argon gas, kept for 4 hours, and cooled to room temperature naturally.

[0041] (3) washing and drying to obtain composite materials

[0042] Put 10 g of the reaction product of step (2) in a beaker, add 500 mL of deioni...

Embodiment 2

[0048] In this embodiment, nano-sheet silicon-carbon composites are prepared according to the following steps:

[0049] (1) Preparation of precursor powder

[0050] Weigh 0.5 g of phenyl cage octahedral silsesquioxane, 4.5 g of lithium chloride and 5.5 g of potassium chloride and grind them in a mortar for 10 min, and mix the ground powder in a ball mill at 500 rpm for 2 h. The ball-milled mixture was dried at 70° C. for 4 h to obtain the precursor powder.

[0051] (2) High temperature magnesia thermal reduction

[0052] Put the precursor powder on one end of the stainless steel burning boat, add 0.5g magnesium powder to the other end, and transfer the burning boat to the tube furnace. Then, the temperature was raised to 300° C. under argon at a heating rate of 5° C. / min, kept for 4 hours, and cooled to room temperature naturally.

[0053] (3) washing and drying to obtain composite materials

[0054] Put 10 g of the reaction product of step (2) in a beaker, add 500 mL of d...

Embodiment 3

[0059] In this embodiment, nano-sheet silicon-carbon composites are prepared according to the following steps:

[0060] (1) Preparation of precursor powder

[0061] Weigh 0.5 g of vinyl cage octahedral silsesquioxane, 4.5 g of lithium chloride and 5.5 g of potassium chloride and grind them in a mortar for 10 min, and mix the ground powder in a ball mill at 500 rpm for 2 h. The ball-milled mixture was dried at 70° C. for 4 h to obtain the precursor powder.

[0062] (2) High temperature magnesia thermal reduction

[0063] Put the precursor powder on one end of the stainless steel burning boat, add 0.5g magnesium powder to the other end, and transfer the burning boat to the tube furnace. Then, the temperature was raised to 300° C. under argon at a heating rate of 5° C. / min, kept for 4 hours, and cooled to room temperature naturally.

[0064] (3) washing and drying to obtain composite materials

[0065] Put 10 g of the reaction product of step (2) in a beaker, add 500 mL of de...

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
diameteraaaaaaaaaa
Login to view more

Abstract

The preparation method comprises the following steps: by taking polyhedral oligomeric silsesquioxane which takes a silicon element as a framework as a precursor, establishing a magnesiothermic reduction reaction process based on a molten salt system, and realizing in-situ conversion of organosiloxane, so as to obtain the nanosheet-shaped silicon-carbon composite material used as the negative electrode material of the lithium ion battery. And thus, the nanosheet-shaped silicon-carbon composite material is obtained. The composite material has excellent cycling stability and lithium storage capacity, the preparation process is simple, the condition is controllable, and the cost is relatively low.

Description

technical field [0001] The invention relates to a preparation method of a lithium-ion battery negative electrode material, in particular to a preparation method of a nano-sheet silicon-carbon composite material used as a lithium-ion battery negative electrode material, and belongs to the technical field of lithium-ion battery negative electrode materials. Background technique [0002] Silicon can form Li with lithium at room temperature 15 Si 4 Alloy, theoretical capacity up to 3590mAh g -1 , has great potential for lithium intercalation. However, the Li intercalation formed by the silicon anode material 15 Si 4 Phase will lead to volume expansion of more than 300%, repeated volume expansion and shrinkage in the process of intercalation / delithiation will lead to particle breakage, and it is also difficult to form a stable solid electrolyte interface film in the electrolyte, which intensifies the corrosion of silicon and capacity decay. In addition, as a semiconductor, ...

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): C01B33/021C01B32/05H01M4/36H01M4/38H01M4/583H01M10/0525B82Y30/00B82Y40/00
CPCY02E60/10
Inventor 范小明杨用三蔡婷杨则恒张卫新
Owner HEFEI UNIV OF 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