CN104993110A - Preparation method of composite negative electrode material for lithium ion battery - Google Patents

Preparation method of composite negative electrode material for lithium ion battery Download PDF

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Publication number
CN104993110A
CN104993110A CN201510315196.8A CN201510315196A CN104993110A CN 104993110 A CN104993110 A CN 104993110A CN 201510315196 A CN201510315196 A CN 201510315196A CN 104993110 A CN104993110 A CN 104993110A
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negative electrode
composite negative
electrode material
preparation
lithium ion
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CN104993110B (en
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苏明如
刘云建
窦爱春
张志强
王起亮
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Jiangsu University
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Jiangsu University
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Silicon Compounds (AREA)

Abstract

The invention discloses a preparation method of a composite negative electrode material for a lithium ion battery. The method is characterized in that the m-Si@G composite negative electrode material is prepared through the combination of a surface modification method and a hydrothermal reduction method. The method specifically includes the following steps of firstly, conducting surface modification on nanometer silicon, adding the nanometer silicon together with a reducing agent to dispersion liquid of graphite oxide, conducting hydrothermal reaction after dispersion is uniform, shifting into a water solution to conduct ion exchange after suction filtration is conducted, and obtaining the composite negative electrode material after suction filtration and freeze drying are conducted. The prepared m-Si@G composite negative electrode material is stable in structure and excellent in circulating performance and rate capability.

Description

A kind of preparation method of composite negative electrode material of lithium ion battery
Technical field
The invention belongs to lithium ion battery material and preparation method thereof field, relate to a kind of lithium ion battery and use mthe preparation method of-Si@G composite negative pole material.
Background technology
Silicium cathode is because having the highest theoretical specific capacity (4 200 mAhg -1), low removal lithium embedded current potential (0.02 ~ 0.6 V vs. Li +/ Li), have received the extensive concern of Chinese scholars; But, electrode material progressively efflorescence fragmentation can be caused in de-/change in volume (~ 300%) that embedding lithium process in which materials itself is huge, to make between silicon grain and and collector between electrical contact be deteriorated, cause the specific capacity of material to decay rapidly, and the adjoint poor high rate performance of lower electron conductivity also hinder the practical application of silicon as lithium ion battery negative material further; And Graphene is because of the physicochemical properties of its excellence, as splendid electronic conductivity and high specific area, simultaneously the pliability of its structure can help buffering other materials to there is larger volume change embedding/deviate from Li process, what is more important, prepare the presoma of Graphene, as graphene oxide, its surface has a large amount of oxygen-containing functional groups, can effectively in conjunction with other ions or functional group, graphene composite negative pole shows huge potentiality in recent years in field of lithium ion battery.
The silicon of current report and the composite material of Graphene mainly adopt the method such as mechanical mixture, suction filtration, freeze drying to prepare, silicon grain is dispersed between graphene sheet layer, and in two-dimentional sandwich, but bond strength is poor on the whole, structural instability, is easily separated in charge and discharge process; In order to improve the chemical property of silicium cathode, invention is a kind of constitutionally stable mthe preparation method of-Si@G composite negative pole material is significant.
Summary of the invention
Technical problem to be solved by this invention is to provide one and prepares mthe method of-Si@G composite negative pole material, suppresses the volumetric expansion of nano-silicon, thus obtains the higher silicium cathode material of structural stability, improves the chemical property of material.
Technical scheme of the present invention comprises the following steps:
Join in absolute ethyl alcohol by nano-silicon, reagent A, water and dispersant, magnetic agitation, control reaction temperature and carry out reaction 1 ~ 48 h at 20-95 DEG C, by the homogeneous suspension filtered that obtains or centrifugation, obtain the nano-silicon after modifying, products therefrom is labeled as m-Si.
By modify after surface with the functional group that can combine with graphite oxide surface functional group nano-silicon ( m-Si) join together with reducing agent in the dispersion liquid of graphite oxide, ultrasonic agitation, and obtain homogeneous suspension, after proceed in hydrothermal reaction kettle and carry out hydro-thermal reaction, products therefrom filter be placed on carry out ion-exchange, washing, drying in the aqueous solution after and get final product m-Si@G composite negative pole material.
Described reagent A is one or more in triethanolamine, the concentrated sulfuric acid, hydrogen peroxide and vinyltrimethoxy silane.
Described nano-silicon is of a size of 30 ~ 300 nm.
Described dispersant is one or more in softex kw, sodium alginate, neopelex and acetone.
Described nano-silicon: water: dispersant: reagent A: the mass ratio=0.5-2:1.5-3:0.05-0.3:0.01-10:25 of absolute ethyl alcohol.
Described reducing agent is one or more in polyvinylpyrrolidone, polyethylene glycol, water soluble chitosan and ethylene glycol, and its consumption is 1 ~ 3 times of theoretical amount.
Described m-Si is 0.2 ~ 1:1 with the mass ratio of graphite oxide.
Described hydrothermal reaction condition is: reaction temperature is 120 ~ 250 DEG C, and the reaction time is 2 ~ 24 h; Described hydro-thermal reaction number of times is 1 ~ 2 time.
Described ion-exchange reaction temperature is normal temperature, and the reaction time is 24 ~ 72 h; Drying mode is freeze drying, and pressure is 60 Mpa, and the time is 48 ~ 72 h.
The beneficial effect that the present invention has is:
The present invention adopts the method that finishing-hydrothermal reduction-ion-exchange combines to prepare m-Si@G composite negative pole material; Finishing is carried out to nano-silicon, nano-silicon not only can be made better to disperse, and active group on nano-silicon surface band can be made, itself and graphite oxide is impelled to carry out the conjunction of chemical combination bond, the structural stability of reinforced composite, thus promote the cyclical stability of composite material, acquisition electrochemical performance m-Si@G composite negative pole material, the composite material prepared by the present invention first embedding/de-lithium performance reaches 1000 more than mAh/g, has very excellent chemical property.
Accompanying drawing explanation
Fig. 1 is in embodiment 1 mthe SEM figure of-Si@G composite material.
Fig. 2 is in example 1 mthe TEM figure that-Si@G composite material is corresponding.
Fig. 3 is in embodiment 1 mthe XRD figure of-Si@G composite material.
Fig. 4 is in embodiment 1 mthe first charge-discharge curve of-Si@G composite material.
Embodiment
Below in conjunction with the drawings and specific embodiments, the invention will be further described.Following embodiment is intended to the present invention instead of limitation of the invention further are described.
Embodiment 1
Take nano-silicon as raw material, in the ethanolic solution of water, select softex kw (CTAB) to be dispersant, triethanolamine is reagent A, control m (nano-silicon) :m (water) :m (CTAB) :m (reagent A) :m (absolute ethyl alcohol)=2 :2 :0.2 :5 :25, reaction temperature is 25 DEG C, and the reaction time is 24 h, after centrifugal m-Si powder.
Will m-Si and graphite oxide are according to 1 :the ratio of 4 is disperseed, adding polyvinylpyrrolidone (adding proportion is 1 times of theoretical amount) is reducing agent, proceed to after ultrasonic agitation is uniformly dispersed in hydrothermal reaction kettle and carry out hydro-thermal reaction, reaction temperature is 160 DEG C, reaction time is 20 h, products therefrom filters and is placed in the aqueous solution and carries out ion-exchange 24 h, after washing, freeze drying 48 h and get final product m-Si@G composite negative pole material.
Gained composite material SEM schemes as shown in Figure 1, and as can be seen from the figure, nano-silicon is wrapped in graphene conductive network well.
As shown in Figure 2, result and sem analysis result are consistent TEM figure, and Graphene is silk shape, and lamella is less, for nano-silicon provides good coated and conductive network.
As shown in Figure 3, nano silicon structure is obvious, and the small peak at 26 places is the characteristic peak of Graphene for XRD figure.As shown in Figure 4, it takes off lithium specific capacity up to 1283.8 mAh/g to chemical property first, electro-chemical activity
Higher.
Embodiment 2
Take nano-silicon as raw material, in the ethanolic solution of water, select neopelex (SDBS) to be dispersant, the mixed liquor of sulfuric acid and hydrogen peroxide is reagent A, control m (nano-silicon) :m (water) :m (SDBS) :m (reagent A) :m (absolute ethyl alcohol)=1 :2 :0.5 :8 :25, reaction temperature is 25 DEG C, and the reaction time is 24 h, after centrifugal m-Si powder.
Will m-Si and graphite oxide are according to 1 :the ratio of 2 is disperseed, adding ethylene glycol (adding proportion is 1.5 times of theoretical amount) is reducing agent, proceed to after ultrasonic agitation is uniformly dispersed in hydrothermal reaction kettle and carry out hydro-thermal reaction, reaction temperature is 180 DEG C, reaction time is 8 h, products therefrom filters to be placed in the aqueous solution and carries out ion-exchange 48 h, washing, freeze drying 60 h, and it takes off lithium specific capacity first up to 1103.9 mAh/g.
Embodiment 3
Take nano-silicon as raw material, in the ethanolic solution of water, select softex kw (CTAB) to be dispersant, triethanolamine is reagent A, control m (nano-silicon) :m (water) :m (CTAB) :m (A) :m (absolute ethyl alcohol)=2 :2 :0.2 :5 :25, reaction temperature is 25 DEG C, and the reaction time is 24 h, after centrifugal m-Si powder.
Will m-Si and graphite oxide are according to 1 :the ratio of 1 is disperseed, adding polyethylene glycol (adding proportion is 3 times of theoretical amount) is reducing agent, proceed to after ultrasonic agitation is uniformly dispersed in hydrothermal reaction kettle and carry out hydro-thermal reaction, reaction temperature is 250 DEG C, reaction time is 4h, products therefrom filters to be placed in the aqueous solution and carries out ion-exchange 72 h, washing, freeze drying 72 h, and it takes off lithium specific capacity first up to 1476.8 mAh/g.

Claims (10)

1. a preparation method for composite negative electrode material of lithium ion battery, is characterized in that: by the nano-silicon of the surface after modification with the functional group that can combine with graphite oxide surface functional group m-Si joins in the dispersion liquid of graphite oxide together with reducing agent, ultrasonic agitation, and obtains homogeneous suspension, after proceed in hydrothermal reaction kettle and carry out hydro-thermal reaction, products therefrom filter be placed on carry out ion-exchange, washing, drying in the aqueous solution after and get final product m-Si@G composite negative pole material.
2. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 1, it is characterized in that: nano-silicon, reagent A, water and dispersant are joined in absolute ethyl alcohol, magnetic agitation, control reaction temperature and carry out reaction 1 ~ 48 h at 20-95 DEG C, by the homogeneous suspension filtered that obtains or centrifugation, obtain the nano-silicon after modifying, products therefrom is labeled as m-Si.
3. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 2, is characterized in that: described reagent A is one or more in triethanolamine, the concentrated sulfuric acid, hydrogen peroxide and vinyltrimethoxy silane.
4. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 2, is characterized in that: described nano-silicon is of a size of 30 ~ 300 nm.
5. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 2, is characterized in that: described dispersant is one or more in softex kw, sodium alginate, neopelex and acetone.
6. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 2, is characterized in that: described nano-silicon: water: dispersant: reagent A: the mass ratio=0.5-2:1.5-3:0.05-0.3:0.01-10:25 of absolute ethyl alcohol.
7. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 1, it is characterized in that: described reducing agent is one or more in polyvinylpyrrolidone, polyethylene glycol, water soluble chitosan and ethylene glycol, its consumption is 1 ~ 3 times of theoretical amount.
8. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 1, is characterized in that: described m-Si is 0.2 ~ 1:1 with the mass ratio of graphite oxide.
9. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 1, is characterized in that: described hydrothermal reaction condition is: reaction temperature is 120 ~ 250 DEG C, and the reaction time is 2 ~ 24 h; Described hydro-thermal reaction number of times is 1 ~ 2 time.
10. the preparation method of a kind of composite negative electrode material of lithium ion battery as claimed in claim 1, is characterized in that: described ion-exchange reaction temperature is normal temperature, and the reaction time is 24 ~ 72 h; Drying mode is freeze drying, and pressure is 60 Mpa, and the time is 48 ~ 72 h.
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Cited By (6)

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CN108172778A (en) * 2017-11-29 2018-06-15 合肥国轩高科动力能源有限公司 Si/SiOxPreparation method of/rGO negative electrode composite material
CN109503166A (en) * 2018-09-29 2019-03-22 东莞市凯金新能源科技股份有限公司 A kind of flatbed lithium ion battery graphite cathode material and preparation method
CN109873150A (en) * 2019-03-14 2019-06-11 西北师范大学 The method for preparing nanometer silicon composite material as raw material using palygorskite
CN110265635A (en) * 2019-05-14 2019-09-20 江苏大学 A kind of preparation method of silicon-carbon composite cathode material of lithium ion battery
CN113415804A (en) * 2021-07-29 2021-09-21 厦门海辰新能源科技有限公司 Carbon-silicon three-dimensional structure composite material and preparation method thereof
CN113488624A (en) * 2021-07-08 2021-10-08 中国恩菲工程技术有限公司 Silicon-carbon composite material and preparation method and application thereof

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108172778A (en) * 2017-11-29 2018-06-15 合肥国轩高科动力能源有限公司 Si/SiOxPreparation method of/rGO negative electrode composite material
CN109503166A (en) * 2018-09-29 2019-03-22 东莞市凯金新能源科技股份有限公司 A kind of flatbed lithium ion battery graphite cathode material and preparation method
CN109503166B (en) * 2018-09-29 2021-07-23 广东凯金新能源科技股份有限公司 Graphite cathode material for platform type lithium ion battery and preparation method thereof
CN109873150A (en) * 2019-03-14 2019-06-11 西北师范大学 The method for preparing nanometer silicon composite material as raw material using palygorskite
CN110265635A (en) * 2019-05-14 2019-09-20 江苏大学 A kind of preparation method of silicon-carbon composite cathode material of lithium ion battery
CN113488624A (en) * 2021-07-08 2021-10-08 中国恩菲工程技术有限公司 Silicon-carbon composite material and preparation method and application thereof
CN113415804A (en) * 2021-07-29 2021-09-21 厦门海辰新能源科技有限公司 Carbon-silicon three-dimensional structure composite material and preparation method thereof
US11817574B2 (en) 2021-07-29 2023-11-14 Xiamen Hithium Energy Storage Technology Co., Ltd. Carbon-silicon three-dimensional structural composite material and preparation method thereof

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