Preparation method for phosphorus-doped three-dimensional structured positive electrode material for lithium-sulfur battery

A lithium-sulfur battery and cathode material technology, applied in battery electrodes, secondary batteries, structural parts, etc., can solve problems such as slowing down the kinetics of electrochemical reactions, reducing the utilization rate of sulfur active materials, and deteriorating the performance of lithium-sulfur batteries , to achieve the effect of reducing the shuttle effect, facilitating the conductivity and shortening the conduction distance

Active Publication Date: 2016-06-29
常熟东南高新技术创业服务有限公司
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This phenomenon, known as the shuttle effect, reduces the availability of sulfur active species
At the same time insoluble Li 2 S and Li 2 S 2 Deposited on the surface of the lithium negative electrode, which further deteriorates the performance of the lithium-sulfur battery; (3) the final product of the reaction, Li 2 S is also an electronic insulator and will be deposited on the sulfur electrode, while lithium ions migrate slowly in solid lithium sulfide, slowing down the electrochemical reaction kinetics; (4) sulfur and the final product Li 2 The density of S is different. When sulfur is lithiated, the volume expands by about 79%, which easily leads to Li 2 Pulverization of S, causing safety problems in lithium-sulfur batteries
The above deficiencies restrict the development of lithium-sulfur batteries, which is also a key issue that needs to be solved in current research on lithium-sulfur batteries.

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 for phosphorus-doped three-dimensional structured positive electrode material for lithium-sulfur battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] (1) Add 10 mg of graphite oxide to 10 mL of ethylene glycol and sonicate for 10 minutes to form a 1 g / L graphene oxide suspension;

[0020] (2) Dissolve triphenylphosphine in ethylene glycol to form a solution with a mass fraction of 10%, take 100mL and add it to the graphene oxide suspension, then transfer it to a hydrothermal kettle for reaction, react at 160°C for 6 hours, and the reaction is complete Finally, wash with ethanol, wash with water, and then freeze-dry to obtain three-dimensional phosphorus-doped graphene;

[0021] (3) Take 10 mg of three-dimensional phosphorus-doped graphene obtained in (2) and 5 mg of Ketjen Black and add them to 15 mL of N-methylpyrrolidone and ultrasonically form a 1 g / L suspension;

[0022] (4) Add 150mg of elemental sulfur to 15mL of N-methylpyrrolidone and sonicate at a certain 40°C until the elemental sulfur is completely dissolved to form a 10g / L suspension;

[0023] (5) Mix the two suspensions obtained in (4) and (3), stir eve...

Embodiment 2

[0025] (1) Add 10 mg of graphite oxide to 1 mL of ethylene glycol and sonicate for 60 minutes to form a 10 g / L graphene oxide suspension;

[0026] (2) Dissolve triphenylphosphine in ethylene glycol to form a solution with a mass fraction of 10%, take 500mL and add it to the graphene oxide suspension, then transfer it to a hydrothermal kettle for reaction, react at 200°C for 1 hour, and the reaction is complete Finally, wash with ethanol, wash with water, and then freeze-dry to obtain three-dimensional phosphorus-doped graphene;

[0027] (3) Take 10 mg of three-dimensional phosphorus-doped graphene obtained in (2) and 0.5 mg of Ketjen black and add it to 2.1 mL of N-methylpyrrolidone and ultrasonically form a 5 g / L suspension;

[0028] (4) Add 210mg of elemental sulfur to 14mL of N-methylpyrrolidone and sonicate at 50°C until the elemental sulfur is completely dissolved to form a 15g / L suspension;

[0029] (5) Mix the two suspensions obtained in (4) and (3), stir evenly, then ...

Embodiment 3

[0031] (1) Add 10 mg of graphite oxide to 5 mL of ethylene glycol and sonicate for 30 minutes to form a 2 g / L graphene oxide suspension;

[0032] (2) Dissolve triphenylphosphine in ethylene glycol to form a solution with a mass fraction of 10%, take 200mL and add it to the graphene oxide suspension, then transfer it to a hydrothermal kettle for reaction, react at 180°C for 3 hours, and the reaction is complete Finally, wash with ethanol, wash with water, and then freeze-dry to obtain three-dimensional phosphorus-doped graphene;

[0033] (3) Take 10 mg of three-dimensional phosphorus-doped graphene obtained in (2) and 1 mg of Ketjen black and add it to 5.5 mL of N-methylpyrrolidone and ultrasonically form a 2 g / L suspension;

[0034] (4) Add 132mg of elemental sulfur to 11mL of N-methylpyrrolidone and sonicate at 45°C until the elemental sulfur is completely dissolved to form a 12g / L suspension;

[0035] (5) Mix the two suspensions obtained in (4) and (3), stir evenly, then sl...

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
Login to view more

Abstract

The invention provides a preparation method for a phosphorus-doped three-dimensional structured positive electrode material for a lithium-sulfur battery. The preparation method comprises the following steps of (1) adding graphite oxide into ethylene glycol, and performing ultrasonic processing to obtain a graphene oxide suspension liquid; (2) dissolving triphenylphosphine into ethylene glycol, and then adding the mixture into the graphene oxide suspension liquid; (3) adding the three-dimensional phosphorus-doped graphene obtained in the step (2) and ketjen black into N-methyl pyrrolidone, and performing an ultrasonic reaction to form a suspension liquid; (4) adding elemental sulfur into the N-methyl pyrrolidone, and performing ultrasonic processing until the elemental sulfur is fully dissolved to form a suspension liquid; and (5) mixing the two kinds of suspension liquid obtained in the steps (4) and (3), uniformly stirring, and slowly adding distilling water while stirring to obtain the three-dimensional structured positive electrode material for the lithium-sulfur battery. Due to the sulfur absorption effect of the phosphorus atoms in the phosphorus-doped graphene, the shuttle flying effect can be effectively reduced, and the cycling life of the lithium-sulfur battery can be prolonged.

Description

technical field [0001] The invention relates to the synthesis of nanometer materials, in particular to a preparation method of a cathode material of a lithium-sulfur battery. Background technique [0002] A lithium-sulfur battery is a battery system in which metallic lithium is used as the negative electrode and elemental sulfur is used as the positive electrode. Lithium-sulfur batteries have two discharge platforms (about 2.4V and 2.1V), but their electrochemical reaction mechanism is relatively complicated. Lithium-sulfur batteries have the advantages of high specific energy (2600Wh / kg), high specific capacity (1675mAh / g), and low cost, and are considered to be a promising new generation of batteries. However, at present, there are problems such as low utilization of active materials, low cycle life and poor safety, which seriously restrict the development of lithium-sulfur batteries. The main reasons for the above problems are as follows: (1) elemental sulfur is an elec...

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): H01M4/36H01M4/38H01M4/62H01M10/0525
CPCH01M4/364H01M4/38H01M4/625H01M4/628H01M10/0525Y02E60/10
Inventor 钟玲珑肖丽芳
Owner 常熟东南高新技术创业服务有限公司
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