A kind of lithium-sulfur battery composite cathode material and preparation method thereof

A technology for composite positive electrode materials and lithium-sulfur batteries, applied to battery electrodes, circuits, electrical components, etc., to achieve the effects of simple preparation methods, improved cycle performance, and high-efficiency utilization

Inactive Publication Date: 2017-07-11
CHINA UNIV OF GEOSCIENCES (WUHAN)
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, maintaining high initial capacity and improving cycle performance at high discharge rates are still not well resolved

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
  • A kind of lithium-sulfur battery composite cathode material and preparation method thereof
  • A kind of lithium-sulfur battery composite cathode material and preparation method thereof
  • A kind of lithium-sulfur battery composite cathode material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0050] Prepare a porous multi-walled carbon nanotube / sulfur / glucose composite positive electrode material with glucose as a modifier, wherein the amount of each component is calculated by mass percentage: conductive agent porous multi-walled carbon nanotube 50wt%, electrochemically active substance sulfur 49.9wt%, modifier glucose 0.1wt%.

[0051] The preparation method of above-mentioned porous multi-wall carbon nanotube is: the potassium hydroxide of solid state and carbon material multi-wall carbon nanotube (aperture is 2-5nm, specific surface area is 324m 2 / g, the pore volume is 0.40cm 3 / g, sold by Nanjing Xianfeng Nano Material Technology Co., Ltd.) uniformly mixed with a mass ratio of 5:1, then placed in a tube furnace, with a mixed gas of hydrogen and nitrogen as a protective atmosphere, wherein the hydrogen volume concentration is 5% , calcined at 850° C. for 1.5 h, then the calcined product was taken out, washed with 1 mol / L dilute hydrochloric acid and then washed...

Embodiment 2

[0059] Prepare a porous multi-walled carbon nanotube / sulfur / glucose composite positive electrode material with glucose as a modifier, wherein the amount of each component is calculated by mass percentage: conductive agent porous multi-walled carbon nanotube 59.4wt%, electrochemically active substance Sulfur 40wt%, modifier glucose 0.6wt%.

[0060] The preparation method of above-mentioned porous multi-wall carbon nanotube is: the potassium hydroxide of solid and multi-wall carbon nanotube (aperture is 2-5nm, specific surface area is 324m 2 / g, the pore volume is 0.40cm 3 / g, sold by Nanjing Xianfeng Nano Material Technology Co., Ltd.) uniformly mixed with a mass ratio of 5:1, then placed in a tube furnace, with a mixed gas of hydrogen and nitrogen as a protective atmosphere, wherein the hydrogen volume concentration was 5% , calcined at 650°C for 1.5h, then the calcined product was taken out, washed with dilute hydrochloric acid and then washed with deionized water until neut...

Embodiment 3

[0068] Preparation of porous multi-walled carbon nanotubes / sulfur / glucose composite positive electrode material with glucose as a modifier, the method is similar to Example 1, the difference is that the amount of each component is calculated by mass percentage: conductive agent porous multi-walled carbon nano Tube 50wt%, electrochemical active substance sulfur 49.2wt%, modifier glucose 0.8wt%.

[0069] In this example, the preparation of the composite positive electrode material, the preparation of the positive electrode sheet, the method of assembling the battery, and the battery test are all the same as in Example 1. The battery charge and discharge test results show that: under the 1C rate, the first charge and discharge of the battery prepared in this example The specific capacity is 754mAh / g, and the specific capacity after 200 cycles is 561mAh / g. The discharge cycle test diagram of the battery is as follows figure 2 shown. Compared with Example 2, the increase of gluco...

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
pore sizeaaaaaaaaaa
specific surface areaaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The present invention relates to a lithium sulfur battery composite positive electrode material and a preparation method thereof. The lithium sulfur battery composite positive electrode material is prepared by using a conductive agent having a mesoporous structure, sulfur, and a modifying agent. The sulfur is dispersed in holes of the conductive agent, the modifying agent is connected to orifices of the conductive agent by using a chemical bonding manner, and the mass ratios of the components are: 30% to 59.4% of the conductive agent, 40% to 60% of the sulfur, and 0.1% to 10% of the modifying agent. The preparation method thereof comprises: pouring sulfur into a conductive agent by adopting a molten suction method, to obtain a conductive agent / sulfur composite material; and then modifying the obtained conductive agent / sulfur composite material, to obtain a lithium sulfur battery composite positive electrode material. The composite positive electrode material not only can implement excellent high-rate stability performance, but also can effectively reduce the loss of active substances and the influence such as lithium negative electrode corrosion and rapid capacity attenuation caused by a "shuttle effect" due to dissolution of lithium polysulfide, thereby remarkably increasing the cycle performance of a lithium sulfur battery.

Description

technical field [0001] The invention relates to the technical field of lithium-sulfur batteries, in particular to a lithium-sulfur battery composite cathode material and a preparation method thereof. Background technique [0002] Monosulfur cathode material according to the electrochemical reaction S 8 +16Li→8Li 2 S meter, its specific capacity is as high as 1675mAh·g -1 , has the highest energy density among the known solid cathode materials, and has abundant sulfur single substance reserves, low price, safety and low toxicity, so it has very broad application prospects. But because sulfur is an electronic insulator (5×10 -30 S cm -1 , 25°C), and the high-valence lithium polysulfides formed during the discharge process (when the lithium-sulfur battery is at different discharge voltages, lithium and sulfur react to form lithium polysulfides with different valence states of sulfur, and the specific products are from high-valence states to low-valence states. The valence ...

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): H01M4/62
CPCH01M4/624H01M4/625H01M4/62Y02E60/10
Inventor 周成冈周吟闫允璠韩波吴金平
Owner CHINA UNIV OF GEOSCIENCES (WUHAN)
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