Porous carbon coated ferrous silicate lithium anode material and preparation method thereof

A technology of lithium ferrosilicate and cathode material, applied in battery electrodes, electrical components, circuits, etc., can solve the problem of affecting the charge and discharge current density and specific capacity of materials, limiting the application of lithium ferrosilicate, and affecting the electrochemical performance of products. and other problems, to achieve the effect of increasing the solid-liquid contact interface area, improving the electrochemical performance, and improving the specific capacity.

Inactive Publication Date: 2010-09-29
TIANJIN UNIV
View PDF5 Cites 27 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method inevitably washes away the soluble ions in the ferrosilicon blend during the washing process, resulting in a mismatch of the stoichiometric ratio, thereby affecting the electrochemical performance of the product.
[0004] The main reason restricting the development of lithium ferrous silicate as positive

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
  • Porous carbon coated ferrous silicate lithium anode material and preparation method thereof
  • Porous carbon coated ferrous silicate lithium anode material and preparation method thereof
  • Porous carbon coated ferrous silicate lithium anode material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019]Lithium acetate, ferrous acetate, and ethyl orthosilicate are used as raw materials, and the corresponding substances are weighed according to the ratio of substances, so that the mass ratio of Li:Fe:Si is 2:1:1, and 1.640g of lithium acetate is accurately weighed, 1.8ml of tetraethyl orthosilicate and 0.399g of polyethylene glycol were dissolved in 13.3ml of ethanol so that the concentration of tetraethyl orthosilicate was 0.6mol / L. The obtained solution system was fully stirred for 10 min and mixed evenly. Accurately weigh 1.391g ferrous acetate, accurately weigh 0.039g ascorbic acid, add it to the above solution, stir to dissolve, and adjust the pH value to 7 with 0.3mol / L ammonia water as a catalyst. The mixed solution was transferred to a reaction kettle, and the reaction kettle was placed in a constant temperature oven to react at 120°C for 20 hours, and the obtained gel mixture was dried in a vacuum oven at 60°C to obtain a xerogel.

[0020] in N 2 Under the pro...

Embodiment 2

[0022] Lithium acetate, ferrous acetate, and ethyl orthosilicate are used as raw materials, and the corresponding substances are weighed according to the ratio of substances, so that the mass ratio of Li:Fe:Si is 2:1:1, and 1.640g of lithium acetate is accurately weighed, 1.8ml of tetraethyl orthosilicate and 0.129g of polyethylene glycol were dissolved in 10.0ml of ethanol so that the concentration of tetraethyl orthosilicate was 0.8mol / L. The obtained solution system was fully stirred for 10 min and mixed evenly. Accurately weigh 1.391g of ferrous acetate and 0.039g of ascorbic acid, add them to the above solution, stir and dissolve, and adjust the pH value to 6 with 0.2mol / L ammonia water as a catalyst. The mixed solution was transferred to a reaction kettle, and the reaction kettle was placed in a constant temperature oven at 140° C. for 17 hours. The obtained gel mixture was dried in a vacuum oven at 70° C. to obtain a xerogel.

[0023] in N 2 Under the protection of th...

Embodiment 3

[0025] Lithium acetate, ferrous acetate, and ethyl orthosilicate are used as raw materials, and the corresponding substances are weighed according to the ratio of substances, so that the mass ratio of Li:Fe:Si is 2:1:1, and 1.640g of lithium acetate is accurately weighed, 1.8ml of tetraethyl orthosilicate and 0.399g of polyethylene glycol were dissolved in 16.0ml of ethanol so that the concentration of tetraethyl orthosilicate was 0.53mol / L. The obtained solution system was fully stirred for 10 min and mixed evenly. Accurately weigh 1.391g of ferrous acetate, accurately weigh 0.039g of ascorbic acid, add it to the above solution, stir and dissolve, and adjust the pH value to 4 with 0.3mol / L ammonia water as a catalyst. The mixed solution was transferred to a reaction kettle, and the reaction kettle was placed in a constant temperature oven at 160° C. for 15 hours. The obtained gel mixture was dried in a vacuum oven at 80° C. to obtain a xerogel.

[0026] in N 2 Under the pro...

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
Average pore diameter of large poresaaaaaaaaaa
Mesopore average pore sizeaaaaaaaaaa
Average pore diameter of large poresaaaaaaaaaa
Login to view more

Abstract

The invention relates to a porous carbon coated ferrous silicate lithium anode material and a preparation method thereof. Polyethylene glycol is adopted as a pore forming agent, gel is formed by the hydrolytic condensation of tetraethoxysilane, and the polyethylene glycol is pyrolyzed to form continuous frames and penetrated macropore/mesoporous port channels in the calcining process of a precursor, wherein the average pore size of the macropore is within 0.5 to 3.9mu m, the average pore size of the mesopore is within 18 to 40nm, and the average porosity is within 57.2 to 71.9 percent. A three-dimensional network structure is formed by the hydrolytic condensation of the tetraethoxysilane, thereby reducing the migration distance in the crystal lattice recombination process and the activation energy required by migration, being beneficial to reducing the reaction temperature and shortening the reaction time and producing the product which has high phase purity and accords with the stoichiometric ratio. The porous structure increases the specific surface area of the material, not only is beneficial to the infiltration of electrolyte in particles, improves the deintercalation probability of lithium ions inside crystals and the utilization ratio of the lithium ions, but also prevents the crystal grains from growing in the calcining process and aggregating in the charging and discharging process and improves the electrochemical property of the anode material.

Description

technical field [0001] The invention relates to a porous carbon-coated lithium ferrous silicate positive electrode material and a preparation method, belonging to the technical field of energy material preparation. Background technique [0002] With the rapid growth of human demand for energy, energy has become an important problem encountered in the economic development of countries all over the world, which has led to urgent problems such as energy crisis and environmental pollution. In energy development, it is of great significance to make full use of natural forces such as wind energy, tidal energy, and solar energy. Due to the discontinuity of these energy sources, to use these natural energies on a large scale requires a matching energy storage device. Lithium-ion battery is a new type of secondary battery. Due to its advantages such as high voltage, high capacity, small size, light weight, long cycle life, good safety performance, and no memory effect, it has become ...

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
IPC IPC(8): H01M4/136H01M4/1397
CPCY02E60/122Y02E60/10
Inventor 蔡舒燕子鹏周幸苗利娟
Owner TIANJIN 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