Preparation method for starch-based porous hard carbon negative electrode material of lithium ion battery

A lithium-ion battery and negative electrode material technology, applied in the direction of battery electrodes, circuits, electrical components, etc., can solve the problems of small diffusion coefficient, unstable SEI film, and easy combustion of batteries, and achieve the effect of strong commercial value

Inactive Publication Date: 2016-06-01
XINJIANG TECHN INST OF PHYSICS & CHEM CHINESE ACAD OF SCI
View PDF4 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the current graphite negative electrode has the following problems: 1. The potential platform is close to the potential of metal lithium, and it is easy to precipitate dendrite Li and cause a short circuit; 2. The SEI film is unstable and prone to Li + Co-embedded graphite layer with organic solvent, resulting in graphite exfoliation and pulverization; 3. Graphite C interlayer spacing (d 002 ≤0.34nm)x C 6 (~0.37nm), the volume change is 8%, which will easily lead to the peeling and pulverization of the graphite layer; 4. The exothermic reaction between graphite and organic solvents will easily produce flammable gases, and the battery is easy to burn; 5. Li + Small diffusion coefficient, difficult to charge quickly
However, most of these existing preparation studies use environmentally unfriendly and non-renewable raw materials as carbon sources, or use complex experimental equipment and conditions that cannot be industrialized

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 starch-based porous hard carbon negative electrode material of lithium ion battery
  • Preparation method for starch-based porous hard carbon negative electrode material of lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] a. Mix cornstarch with a buffer solution with a pH value of 4 which is potassium dihydrogen phosphate-sodium hydroxide at a mass ratio of 2:3, add the mixture to a temperature of 55°C and stir for 10 minutes, then add the relative cornstarch mass fraction 1% compound enzyme α-amylase and glucoamylase were mixed according to a mass ratio of 5:1, and stirred for 20 hours to obtain a mixture;

[0021] b. The mixture in step a is subjected to suction filtration and water washing for 3 times and then dried to obtain a solid;

[0022] c. Mix the solid obtained in step b and the dehydration catalyst as ammonium chloride uniformly by 5% by mass to obtain a solid phase mixture;

[0023] d. Pre-carbonize the solid-phase mixture obtained in step c in a vacuum oven at a temperature of 170°C for 12 hours to obtain a black pre-carbonized product;

[0024] e. The pre-carbonized product obtained in step d is subjected to suction filtration and water washing for 3 times, and then dried...

Embodiment 2

[0026] a. Mix rice starch with a buffer solution with a pH value of 6 as acetic acid-ammonium acetate at a mass ratio of 2:3, add the mixture to a temperature of 55°C and stir for 10 minutes, and add 3% of the relative weight of rice starch. The enzyme α-amylase and glucoamylase are mixed according to the mass ratio of 10:1, and stirred for 20 hours to obtain a mixture;

[0027] b. The mixture in step a is subjected to suction filtration and water washing for 3 times and then dried to obtain a solid;

[0028] c. Uniformly mixing the solid obtained in step b with the dehydration catalyst as ammonium chloride by 5% by mass to obtain a solid phase mixture;

[0029] d. Pre-carbonize the solid-phase mixture obtained in step c in a vacuum oven at a temperature of 250° C. for 12 hours to obtain a black pre-carbonized product;

[0030] e. The pre-carbonized product obtained in step d is subjected to three times of suction filtration and water washing, and then dried, then put into a ...

Embodiment 3

[0032] a. Mix rice starch and a buffer solution with a pH value of 7 which is disodium hydrogen phosphate-citric acid at a mass ratio of 2:3, add the mixture to a temperature of 55°C and stir for 10 minutes, and add 2% relative starch mass fraction The compound enzyme is α-amylase and glucoamylase mixed in a mass ratio of 8:1, stirred for 20h to obtain a mixture;

[0033] b. The mixture in step a is subjected to suction filtration and water washing for 3 times and then dried to obtain a solid;

[0034] c. Uniformly mix the solid obtained in step b with the dehydration catalyst as ammonium sulfate at 8% by mass to obtain a solid phase mixture;

[0035] d. Pre-carbonize the solid-phase mixture obtained in step c in a vacuum oven at a temperature of 200° C. for 12 hours to obtain a black pre-carbonized product;

[0036] e. The pre-carbonized product obtained in step d is subjected to three times of suction filtration and water washing, and then dried, then put into a heating fur...

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
current efficiencyaaaaaaaaaa
current efficiencyaaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method for a starch-based porous hard carbon negative electrode material of a lithium ion battery. The method comprises the following steps of firstly, obtaining porous starch through enzymatic hydrolysis of composite bio-enzyme; secondly, reserving a hole morphology of the starch through a pre-carbonization process; and finally, obtaining a porous structured negative electrode material of the lithium ion battery through a carbonization process. The starch-based porous hard carbon for the negative electrode material of the lithium ion battery, obtained through the preparation method, has the characteristics of favorable electrochemical performance, high cycle stability and excellent consistency in batch products, the whole process is suitable for industrial production, and meanwhile, the morphology reservation of the porous starch is promoted. The method has the advantages of simplicity in operation, environmental friendliness in production and easiness in mass production, and the product quality is easy to control.

Description

technical field [0001] The invention belongs to the field of preparation of lithium ion battery negative electrode materials. Background technique [0002] Lithium-ion battery is a new type of high-energy secondary battery that began to be put into practical use in the 1990s. It has the advantages of high working voltage, light weight, large specific energy, small self-discharge, long cycle life, no memory effect and low environmental pollution. Lithium-ion battery anode materials are mainly carbon, mainly artificial graphite, natural graphite and amorphous carbon. However, the current graphite negative electrode has the following problems: 1. The potential platform is close to the potential of metal lithium, and it is easy to precipitate dendrite Li and cause a short circuit; 2. The SEI film is unstable and prone to Li + Co-embedded graphite layer with organic solvent, resulting in graphite exfoliation and pulverization; 3. Graphite C interlayer spacing (d 002 ≤0.34nm)<...

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): H01M4/36H01M4/60H01M4/587
CPCH01M4/36H01M4/587H01M4/60Y02E60/10
Inventor 王磊苏蒙谢秋生王建明孙毅徐金宝任卫边亮常爱民
Owner XINJIANG TECHN INST OF PHYSICS & CHEM CHINESE ACAD OF SCI
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