Fluorine-free preparation method for three-dimensional porous silica powder anode material of lithium ion battery

A technology of lithium-ion batteries and negative electrode materials, which is applied in the field of electrochemical power sources, can solve the problems of hydrofluoric acid toxicity and strong corrosion, improve the specific capacity and cycle stability of materials, reduce the cost of material preparation, and avoid environmental pollution Effect

Active Publication Date: 2011-11-09
CHINA THREE GORGES UNIV +1
View PDF4 Cites 53 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The preparation of porous silicon film is realized by electrochemical anodic oxidation or chemical etching process. Both processes use hydrofluoric acid to preferentially corrode the specific crystal direction of single crystal silicon to realize the growth of pores, and the method of creating pores on polycrystalline silicon particles less research
On the other hand, hydrofluoric acid is highly toxic and corrosive, and has high requirements for experimental operations.

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
  • Fluorine-free preparation method for three-dimensional porous silica powder anode material of lithium ion battery
  • Fluorine-free preparation method for three-dimensional porous silica powder anode material of lithium ion battery
  • Fluorine-free preparation method for three-dimensional porous silica powder anode material of lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0042] Example 1. The three-dimensional porous silicon powder negative electrode material of lithium ion battery was prepared according to the method of the preparation example. During the preparation, the decomposition temperature of magnesium silicide was set at 800° C., and other conditions were according to the scheme of the preparation example. The obtained porous silicon material was prepared as electrode for electrochemical test. The electrode preparation method, battery assembly and test conditions are the same as in Comparative Example 1. The lithium intercalation capacity of the material for the first time is 2883.3mAh / g, the lithium delithiation capacity is 1821.0mAh / g, and the coulombic efficiency is 63.2%. The lithium insertion capacity of the 10th cycle is 123.0mAh / g, and the lithium removal capacity is 119.0mAh / g. The capacity retention rate is 6.53%, and the capacity decay is large. Pure nano-silicon electrode material has poor electrochemical performance. At...

Embodiment 2

[0043] Example 2. The three-dimensional porous silicon powder negative electrode material for lithium-ion batteries was prepared according to the method of the preparation example. During the preparation, the decomposition temperature of magnesium silicide was set at 900° C., and other conditions were according to the scheme of the preparation example. The obtained porous silicon material was prepared as electrode for electrochemical test. The electrode preparation method, battery assembly and test conditions are the same as in Comparative Example 1. The first lithium intercalation capacity of the material is 2007.8mAh / g, the lithium delithiation capacity is 1185.0mAh / g, and the coulombic efficiency is 59.0%. The lithium insertion capacity of the 10th cycle is 529.6mAh / g, the lithium removal capacity is 507.8mAh / g, and the capacity retention rate is 42.85%. After 70 cycles, its lithium intercalation capacity was 211.7mAh / g, its delithiation capacity was 214.0 mAh / g, and its c...

Embodiment 3

[0044] Example 3. The three-dimensional porous silicon powder negative electrode material of lithium ion battery was prepared according to the method of the preparation example. During the preparation, the decomposition temperature of magnesium silicide was set to 1000° C., and other conditions were according to the scheme of the preparation example. The obtained porous silicon material was prepared as electrode for electrochemical test. The electrode preparation method, battery assembly and test conditions are the same as in Comparative Example 1. The first lithium intercalation capacity of the material is 2184.1mAh / g, the first delithiation capacity is 1296.8mAh / g, and the Coulombic efficiency is 59.4%. After 10 cycles, the material can still release a reversible capacity of 596.8mAh / g stably, with a capacity retention rate of 46.02%. After 70 cycles, its lithium intercalation capacity was 261.0mAh / g, its delithiation capacity was 258.2 mAh / g, and its capacity retention rat...

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
electrical conductivityaaaaaaaaaa
current efficiencyaaaaaaaaaa
current efficiencyaaaaaaaaaa
Login to view more

Abstract

The invention discloses a fluorine-free preparation method for a three-dimensional porous silica powder anode material of a lithium ion battery. In the method, combination reaction is performed on ordinary micron-sized silicon and magnesium particles to generate magnesium silicide, and the magnesium silicide is pyrolyzed at high temperature to form magnesium vapor and silica powder with a three-dimensional porous structure. By the fluorine-free preparation method for the three-dimensional porous silica powder anode material of the lithium ion battery, a preparation process is free from fluorine so as to avoid environmental pollutions; the material has the porous structure so as to realize the self-absorption of volume effects of the silicon particles; the specific capacity and recycling stability of the material are improved to a certain extent; and a synthesis process is simple and easy to operate, and the preparation cost of the material is low.

Description

technical field [0001] The invention belongs to the field of electrochemical power sources, and in particular relates to a preparation method technology of a lithium-ion battery porous silicon negative electrode material. Background technique [0002] In addition to carbon-based anode materials in negative electrode research, many studies have focused on metals (such as Al, Zn, Cu, Sn, etc.), semiconductors (Si), metal oxides (such as CoO, Co 3 o 4 、Cu 2 O, NiO, FeO, SnO, SiOx), phosphide (Sn 4 P 3 ), lithium transition metal nitride Li 3-x m x N (M is Co, Cu, Ni) and phosphide Li 7 MP 4 (M is Ti, V, Mn) and other materials. The first cycle efficiency of metal oxides is low, and the delithiation potential is too high; lithium transition metal nitrides may decompose to generate nitrogen gas during short circuit or over discharge; lithium intercalated phosphides will release toxic gas phosphine in the air, which is safe Hidden danger. For lithium alloys, the battery ...

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): H01M4/1395
CPCY02E60/12Y02E60/122Y02E60/10
Inventor 杨学林石长川余德馨王凤军
Owner CHINA THREE GORGES UNIV
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