Sulfur/carbon composite material for lithium-sulfur secondary battery and preparation method thereof

A technology of lithium-sulfur secondary batteries and carbon composite materials, which is applied in battery electrodes, electrode manufacturing, non-aqueous electrolyte battery electrodes, etc., can solve the problems of low electrochemical capacity of sulfur electrodes, achieve good application prospects, improve reactivity, The effect of high charge and discharge efficiency

Inactive Publication Date: 2013-03-13
WUHAN UNIV
View PDF7 Cites 28 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, during the discharge process of the sulfur electrode, the sulfur intermediate product insoluble in the electrolyte immediately deposits on the surface of the sulfur electrode, seals the surface of the sulfur electr...

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
  • Sulfur/carbon composite material for lithium-sulfur secondary battery and preparation method thereof
  • Sulfur/carbon composite material for lithium-sulfur secondary battery and preparation method thereof
  • Sulfur/carbon composite material for lithium-sulfur secondary battery and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] 1) Preparation of porous carbon: Dissolve 10 g of sucrose in 200 mL of 6M H 2 SO 4 Then, add 0.05g of VGCF nano-carbon fiber after nitric acid treatment, stir vigorously, and after hydrothermal reaction at 180°C for 24h, suction filter, wash and dry; finally, carbonize at 1000°C for 2h at high temperature to obtain a grape bunch structure microporous carbon matrix (such as figure 1 ).

[0025] 2) Preparation of sulfur / carbon composite cathode material: 0.1g of sublimed sulfur and 0.2g of porous carbon were placed in different glass vials, which were then sealed in a reaction vessel filled with Ar, and placed in a muffle furnace at 400 After heating at ℃ for 6h, a sulfur-carbon composite material with a sulfur content of 60% was prepared.

[0026]3) Prepare a circular pole piece with a diameter of 1cm using sulfur-carbon composite material: use acetylene black as the conductive agent, PTFE (polytetrafluoroethylene) as the paste, and combine the prepared sulfur-carbon...

Embodiment 2

[0032] After the microporous carbon matrix was prepared according to the above method, 0.1 g of sublimed sulfur and 0.4 g of porous carbon were placed in different glass sample vials, which were then sealed in a reaction kettle filled with Ar, and heated in a muffle furnace at 400 After heating at ℃ for 6h, a sulfur-carbon composite material with a sulfur content of 70% was prepared. After being prepared into a positive electrode sheet, the battery was assembled in the same way using the same organic carbonate electrolyte.

[0033] Charge and discharge tests were carried out on the installed battery at room temperature, with a voltage range of 1.0V-3.0V and a current density of 100mA / g. like Figure 6 As shown, the capacity of the sulfur / carbon composite cathode remained at about 450 mAh / g after 50 cycles, and its charge-discharge Coulombic efficiency remained at 100%, indicating that the composite material with higher sulfur content also has good electrochemical performance....

Embodiment 3

[0036] According to the method described in Example 1, after preparing a sulfur / carbon composite material and a positive electrode sheet with a sulfur content of 60%, the (PP13)TFSI ionic liquid containing 1M LiTFSI is used as the electrolyte (wherein, PP13 represents N-methyl-N-propane Basepiperidinium cation, TFSI means N (CF 3 SO 2 ) 2- anion), the battery was assembled in the same manner.

[0037] Charge and discharge tests were carried out on the installed battery at room temperature, with a voltage range of 1.0V-3.0V and a current density of 100mA / g. like Figure 7 As shown, the charging capacity of the sulfur / carbon composite was 1200 mAh / g in the first week, and after 100 cycles, the capacity remained above 800 mAh / g, and the Coulombic efficiency remained at 100% after 3 weeks.

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 sulfur/carbon composite material for a lithium-sulfur secondary battery and a preparation method thereof. The composite material is formed by compositing a micro-pore carbon substrate with a lithium ion conduction property and elemental sulfur filled in the micro-pore structure. The carbon substrate is used as an electronic conductor in the composite material, and is further used as a lithium ion conductor, so that sulfur electrode reaction is directly carried out on a sulfur/carbon solid-solid interface in a conversion reaction manner without directly contacting with electrolyte. Therefore, the problem of circulation caused by that a polysulfide intermediate product is dissolved in the electrolyte can be solved. Compared with the other sulfur/carbon composite electrode, the composite material has the advantages of high electrochemical capacity, good circulation stability, high charging and discharging efficiency and the like; and meanwhile, the preparation method is simple and low in cost, and has a good application prospect.

Description

[0001] technical field [0002] The invention relates to a sulfur / carbon composite cathode material for a lithium-sulfur secondary battery and a preparation method thereof, belonging to the technical field of chemical power sources. Background technique [0003] With the increasing functional integration of portable electronic products and the rapid development of electric vehicles and energy storage power stations, people's demand for high energy density and low-cost secondary batteries is increasingly strong. Since the lithium-sulfur secondary battery has a theoretical energy density of up to 2600 Wh / kg, and the elemental sulfur as a positive electrode material has the advantages of abundant resources and low price, the lithium-sulfur secondary battery is considered to be the next high-end lithium-ion battery. The focus of specific energy secondary battery development. [0004] However, due to the elemental sulfur (S) and its reduction final product lithium sulfide (Li 2...

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): H01M4/13H01M4/38H01M4/62H01M4/04
CPCY02E60/122Y02E60/10
Inventor 艾新平张文华钱江锋杨汉西曹余良
Owner WUHAN 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