Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of nitrogen-doped graphene for cathode of lithium ion battery

A technology of nitrogen-doped graphene and lithium-ion batteries, which is applied in the field of preparation of nitrogen-doped graphene, can solve the problems of being unsuitable for large-scale production, graphene difficulties, and high temperature requirements, and achieves easy operation of preparation equipment, low price, and low energy consumption. short-term effect

Inactive Publication Date: 2015-04-01
百顺松涛(天津)动力电池科技发展有限公司
View PDF9 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method is difficult to prepare large-area graphene with a single thickness, and requires a temperature higher than 1100°C, which consumes a lot of energy and is not suitable for large-scale production.

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 nitrogen-doped graphene for cathode of lithium ion battery
  • Preparation method of nitrogen-doped graphene for cathode of lithium ion battery
  • Preparation method of nitrogen-doped graphene for cathode of lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] A method for preparing nitrogen-doped graphene for negative electrodes of lithium-ion batteries, comprising three processes: preparation of graphene oxide, reduction of graphene oxide, and preparation of nitrogen-doped graphene:

[0040] 1. The preparation process of graphene oxide

[0041] 1), 0.5 g of graphite powder and 1.5 g of potassium permanganate were added to 20 mL of concentrated sulfuric acid with a mass concentration of 98%, and uniformly stirred at 25° C., and then the entire reaction system was stirred at 60° C. for 2.5 hours;

[0042] 2), pour the mixture obtained after the reaction in step 1) into 200 mL of deionized water, continue to stir for 15 min, and then add 15 mL of hydrogen peroxide with a mass fraction of 30%;

[0043] 3), carry out suction filtration, wash away metal ions with the dilute hydrochloric acid that mass fraction is 15%, remove acid again with deionized water;

[0044] 4), adding the solid obtained in step 3) into 200mL deionized w...

Embodiment 2

[0051] A method for preparing nitrogen-doped graphene for negative electrodes of lithium-ion batteries, comprising three processes of preparation of graphene oxide, reduction of graphene oxide and preparation of nitrogen-doped graphene, wherein the first two processes are the same as in Example 1, During the preparation of nitrogen-doped graphene, the graphene prepared by reducing graphene oxide is placed in a vacuum tube furnace and annealed at a high temperature under an ammonia atmosphere at 500 °C. The amount of nitrogen doped in the prepared nitrogen-doped graphene is 4.98at%, and the low current (45mA / g) reversible specific capacity is 827mAh / g.

Embodiment 3

[0053] A method for preparing nitrogen-doped graphene for negative electrodes of lithium-ion batteries, comprising three processes of preparation of graphene oxide, reduction of graphene oxide and preparation of nitrogen-doped graphene, wherein the first two processes are the same as in Example 1, During the preparation of nitrogen-doped graphene, the graphene prepared by reducing graphene oxide is placed in a vacuum tube furnace and annealed at a high temperature under an ammonia atmosphere at 700 °C. The amount of nitrogen doped in the prepared nitrogen-doped graphene is 4.77at%, and the low current (45mA / g) reversible specific capacity is 790mAh / g.

[0054] The above three examples illustrate that the temperature of 500°C is not enough for nitrogen ions and graphene decomposed from ammonia to completely generate carbon-nitrogen bonds; and the reason for the low amount of nitrogen doping at 700°C is that nitrogen doping is more likely to occur in defects or graphene Edge, th...

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

No PUM Login to View More

Abstract

The invention provides a preparation method of nitrogen-doped graphene for a cathode of a lithium ion battery. The method comprises three processes: preparing graphene oxide, restoring graphene oxide, and preparing the nitrogen-doped graphene. The nitrogen-doped graphene is prepared by the following steps: restoring the graphene oxide into prepared graphene; putting into a vacuum tube furnace; and carrying out high-temperature annealing in an ammonia gas at 500-700 DEG C. The prepared nitrogen-doped graphene is annealed in a high-temperature environment until the nitrogen doping amount reaches the maximal value, thus the electronic structure of the graphene is changed; the density of a free carrier of the graphene is improved; and the conductive property, the stability, the first charge-discharge efficiency and the reversible capacity of the graphene are further improved.

Description

technical field [0001] The invention relates to the technical field of graphene preparation, in particular to a method for preparing nitrogen-doped graphene used for lithium-ion battery negative electrodes. Background technique [0002] The research on lithium-ion battery anode materials mainly focuses on carbonaceous materials, alloy materials and composite materials. Carbonaceous materials are the earliest materials studied by people and applied to the commercialization of lithium-ion batteries, and they are still one of the focuses of everyone's attention and research. Carbonaceous materials can be divided into graphitizable carbon (soft carbon), amorphous carbon (hard carbon) and graphite according to their structural characteristics. At present, the research on carbon negative electrode mainly uses various methods to modify its surface, but the surface treatment of artificial graphite will further increase the manufacturing cost, so the focus of future research will st...

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): C01B31/04
Inventor 王卿
Owner 百顺松涛(天津)动力电池科技发展有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com