Preparation method of composite positive pole material for lithium sulphur battery

A composite cathode material, lithium-sulfur battery technology, applied in battery electrodes, circuits, electrical components, etc., can solve the problems of increased transmission impedance of carbon materials, low sulfur content of composite materials, slow volatilization process, etc. The effect of electrical conductivity and fast diffusion

Inactive Publication Date: 2015-05-20
SHENZHEN RES INST CENT SOUTH UNIV
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The single activation of potassium hydroxide on the carbon airgel material prepared by the sol-gel method increases its specific surface area and pore volume, but after activation, the pore volume increases, the pores increase, the carbon structure is destroyed, and the electrical conductivity Weaken, the transmission impedance of carbon materials increases
[0005] Chinese patent CN101891930A discloses a method for preparing carbon nanotube sulfur-based composite cathode materials by heat treatment, which is beneficial to the dispersion of carbon nanotubes and the absorption of sulfur Uniform distribution, but low and difficult to control sulfur content in composites
The preparation method is simple, and the sulfur loading capacity of the composite material is high, but it takes a long time to remove the solvent through natural volatilization or heating volatilization; the volatilization process is slow, and the sulfur will slowly crystallize, resulting in large and uneven particle sizes of precipitated sulfur

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
  • Preparation method of composite positive pole material for lithium sulphur battery
  • Preparation method of composite positive pole material for lithium sulphur battery
  • Preparation method of composite positive pole material for lithium sulphur battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Add 4g of potassium hydroxide and 2g of melamine to 1g of charcoal airgel at the same time, mix well, pour into a nickel crucible, place in a muffle furnace and heat to 800°C under an inert atmosphere of argon or nitrogen, and keep it warm for 2 hours. The obtained solid was washed with dilute sulfuric acid solution, then washed with distilled water or ethanol until neutral, and dried at 120°C to obtain a carbon airgel material modified by activation + nitrogen doping synchronous process. The specific surface area of ​​the modified carbon airgel is increased from that of the unmodified 620 m 2 / g increased to 1958m 2 / g, pore volume from 0.34 cm 3 / g increased to 0.67cm 3 / g, the nitrogen doping amount reaches 15.8at%.

[0028] At room temperature, 2 g of elemental sulfur was dissolved in 40 g of carbon disulfide organic solvent to form an organic sulfur solution with a sulfur content of 5%, and 0.37 g of modified carbon airgel material was slowly added, and ultrasoni...

Embodiment 2

[0032] At room temperature, 2 g of elemental sulfur was dissolved in 10 g of toluene organic solvent to form an organic sulfur solution with a sulfur content of 20%, and 1.2 g of the modified carbon airgel material obtained according to the method of Example 1 was slowly added, and ultrasonically oscillated at room temperature for 1 hour. Then put the solution into the extraction kettle, use supercritical propylene fluid as the extraction agent to carry out anti-solvent crystallization extraction, the extraction temperature is 150°C, the pressure is 28MPa, the time is 50 minutes, and the flow rate of the supercritical fluid is 500 ml / min; Separation under reduced pressure, the separation pressure is 4MPa, the separation temperature is 45°C, and then rinsed with ethanol eluent. After vacuum drying at 60°C, a carbon airgel-sulfur cathode composite material modified with a sulfur content of 58.4% was obtained.

Embodiment 3

[0034] At room temperature, 2 g of elemental sulfur was dissolved in 40 g of benzene organic solvent to form an organic sulfur solution with a sulfur content of 5%, and 0.23 g of the modified carbon airgel material obtained according to the method of Example 1 was slowly added, and ultrasonically oscillated at room temperature. Then the solution is put into the extraction kettle, and the anti-solvent crystallization extraction is carried out with supercritical cyclohexane fluid as the extraction agent. The extraction temperature is 300° C., the pressure is 30 MPa, the time is 55 minutes, and the flow rate of the supercritical fluid is 900 ml / Minutes; separated under reduced pressure, the separation pressure is 5 MPa, the separation temperature is 40 ° C, and then rinsed with ethanol eluent. After vacuum drying at 60°C, a carbon airgel-sulfur cathode composite material modified with a sulfur content of 88.9% was obtained.

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 invention discloses a preparation method of a composite positive pole material of a lithium sulphur battery. The preparation method comprises the following steps of: (1) utilizing activation and nitrogen doping to simultaneously carry out modification on a carbon aerogel to obtain a modified carbon aerogel material; and (2) slowly adding the modified carbon aerogel in an organic sulfur solution, taking a supercritical fluid as an extraction agent to ultrasonically extract in an extraction kettle under room temperature, carrying out pressure reduction and separation, leaching by an ethanol eluting agent, and drying to obtain the modified carbon aerogel-sulfur composite positive pole material. The material prepared by the preparation method provided by the invention has the advantages that the sulfur content is high, the sulfur particles are small, the granularity is uniformly controllable, and the material simultaneously has higher conductibility, specific surface area and porosity. The recovery of the used organic solvent is simple in the preparation process, the extraction agent is circularly used through compression, the extraction efficiency is high, the operation is simple, and the pollution is not generated.

Description

technical field [0001] The invention belongs to the field of new energy, and relates to a method for preparing a cathode material of a lithium-sulfur battery, in particular to a method for preparing a carbon aerogel-sulfur composite anode material. Background technique [0002] With the popularization of portable electronic products, the rapid development of energy storage technology and electric vehicles, the requirements for the energy density and power density of lithium-ion batteries are getting higher and higher. It is predicted that the future 4G mobile communication requires the energy density of the battery to reach more than 500Wh / Kg. Lithium-sulfur batteries have high specific capacity (1675 mAh / g) and high energy density (2600 Wh / kg), and the positive electrode material elemental sulfur is abundant, cheap, and environmentally friendly. Therefore, lithium-sulfur batteries are high-energy-density secondary batteries with great development potential and application ...

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): H01M4/38H01M4/62
CPCY02E60/10
Inventor 张治安李劼蒋绍峰卢海赖延清贾明
Owner SHENZHEN RES INST CENT SOUTH 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

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