Unlock instant, AI-driven research and patent intelligence for your innovation.

A kind of doped graphene modified lithium titanate composite negative electrode material and preparation method thereof

The technology of one kind of lithium titanate and negative electrode material, applied in the field of lithium ion materials, can solve the problems of cumbersome process, unfavorable large-scale production, low theoretical capacity of lithium titanate material, etc., to achieve high energy transfer rate, easy operation of production equipment, The effect of improving high-rate charge-discharge performance

Active Publication Date: 2019-01-11
李震祺 +1
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Since the advent of graphene in 2004, it has attracted widespread attention due to its special properties. Some technicians have also used it to improve the conductivity of lithium titanate materials, but most of them use reactor hydrothermal reaction or sol-gel method to prepare composite materials. , the process is cumbersome, which is not conducive to large-scale industrial production; and because the theoretical capacity of the lithium titanate material is relatively low, it is necessary to further increase the conductivity of the lithium titanate negative electrode material to improve the utilization rate of the active material and maximize the capacity. To meet the needs of power battery energy density, so the existing technology needs to be further improved and improved

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] N-doped n-type graphene dopant and lithium titanate Li 4 Ti 5 o 12 The composite material, the doping and coating amount of the graphene dopant is 15% (weight percent), prepared by the following steps:

[0034] Step S1: firstly, graphene oxide is prepared by ultrasonic-assisted Hummers method. Then melamine and graphene oxide powder are mixed and ground according to the weight ratio of 1:5, and then heated in an Ar gas atmosphere furnace at 800°C for 8 hours, and naturally cooled to obtain an N-doped n-type graphene dopant, wherein N-doped Impurity 10% (weight percentage).

[0035] Step S2: Accurately weigh Li according to the molar ratio of Li:Ti of 0.84 2 CO 3 and TiO 2 , ball milled in ethanol dispersion medium for 4 hours to mix evenly, dried the mixture, placed in a corundum boat, kept at 600°C for 6 hours, and cooled in the furnace to obtain pure phase lithium titanate Li with low crystallinity 4 Ti 5 o 12 Precursor powder.

[0036] Step S3: Mix N-doped ...

Embodiment 2

[0039] B-doped p-type graphene dopant and lithium titanate Li 4 Ti 5 o12 The composite material, the doping of described graphene dopant, coating amount is 20%, adopts the following steps to prepare:

[0040] Step S1: firstly, graphene oxide is prepared by ultrasonic-assisted Hummers method. Then benzene diboronic acid and graphene oxide powder are mixed and ground according to the weight ratio of 8:5, and then heated at 750°C for 8 hours in an Ar gas atmosphere furnace, and naturally cooled to obtain a B-doped p-type graphene doped body, wherein B The doping amount is 8% (weight percentage).

[0041] Step S2: Accurately weigh Li according to the molar ratio of Li:Ti of 0.84 2 CO 3 and TiO 2 , ball milled in ethanol dispersion medium for 3 hours to mix evenly, dried the mixture, placed in a corundum boat, kept at 500°C for 8 hours, and cooled in the furnace to obtain pure phase lithium titanate Li with low crystallinity 4 Ti 5 o 12 Precursor powder.

[0042] Step S3: ...

Embodiment 3

[0045] n-type graphene dopant formed by P doping and lithium titanate Li 4 Ti 5 o 12 The composite material, the doping of described graphene dopant, coating amount is 10%, adopts the following steps to prepare:

[0046] Step S1: firstly, graphene oxide is prepared by ultrasonic-assisted Hummers method. Then red phosphorus and graphene oxide powder are mixed and ground according to the weight ratio of 1:9, then heated at 600°C for 6 hours in an Ar gas atmosphere furnace, and cooled naturally to obtain a P-doped n-type graphene dopant, wherein P-doped Impurity is 10% (weight percentage).

[0047] Step S2: Accurately weigh Li according to the molar ratio of Li:Ti of 0.84 2 CO 3 and TiO 2 , ball milled in an ethanol dispersion medium for 2 hours to mix evenly, dried the mixture, placed it in a corundum boat, kept it at 600°C for 8 hours, and cooled it in the furnace to obtain pure phase lithium titanate Li with low crystallinity 4 Ti 5 o 12 Precursor powder.

[0048] St...

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
cycle efficiencyaaaaaaaaaa
cycle efficiencyaaaaaaaaaa
cycle efficiencyaaaaaaaaaa
Login to View More

Abstract

The invention provides a doped graphene-modified lithium titanate composite anode material and a preparation method thereof. Doped graphene is coated with or doped into a lithium titanate material, wherein the coating amount or the doping amount of the doped graphene is 10%-20%. By the technical scheme of the invention, the electrical conductivity of the lithium titanate material is improved with a graphene doping body; the capacity development and the high-rate charge-discharge property are improved; the development requirements of a high-energy and high-power power battery are met; and the preparation technology and production equipment are convenient to operate and are suitable for industrial large-scale production.

Description

technical field [0001] The invention belongs to the technical field of lithium ion materials, and in particular relates to a doped graphene-modified lithium titanate composite negative electrode material and a preparation method thereof. Background technique [0002] At present, the anode materials of commercialized lithium-ion batteries are mainly carbon materials, but the potential of carbon materials to metal lithium is low. During the charging and discharging process, metal lithium is easily precipitated to produce lithium dendrites, which can easily pierce the separator and cause internal short circuit of lithium-ion batteries. cause safety hazards. At the same time, graphite-based carbon materials also have the problem of solvent co-embedding, resulting in poor cycle performance of high-rate charge-discharge. With the growing demand for power lithium-ion batteries, people urgently need to find a safe, reliable, and cycle-performing anode material. to replace carbon an...

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): H01M4/36H01M4/485H01M4/587H01M4/62H01M10/0525
CPCH01M4/366H01M4/485H01M4/587H01M4/625H01M10/0525Y02E60/10
Inventor 李震祺刘立君宋翠环
Owner 李震祺