CN109473648B - Silicon-carbon composite material for lithium ion battery and preparation method thereof - Google Patents

Silicon-carbon composite material for lithium ion battery and preparation method thereof Download PDF

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CN109473648B
CN109473648B CN201811303288.4A CN201811303288A CN109473648B CN 109473648 B CN109473648 B CN 109473648B CN 201811303288 A CN201811303288 A CN 201811303288A CN 109473648 B CN109473648 B CN 109473648B
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silicon
lithium ion
coating agent
ion battery
composite material
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CN109473648A (en
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刘文平
秦海青
雷晓旭
张振军
卢安军
林峰
卢宗柳
张建伟
蒙光海
王立惠
夏村村
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China Nonferrous Metal Guilin Geology and Mining Co Ltd
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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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • 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
    • 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
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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

Abstract

The invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of a precursor core and a modified polymer coating layer, wherein the precursor core comprises nano silicon powder, a cracking carbon source and graphite powder, the modified polymer coating layer is made of a coating agent, and the coating agent comprises ethyl cellulose or polyvinylidene fluoride; can effectively inhibit the volume expansion of the nano silicon carbon powder, thereby improving the cycle performance and the capacity of the lithium ion battery. Meanwhile, the invention provides a preparation method of the silicon-carbon composite material for the lithium ion battery, which is simple and efficient, and the silicon-carbon composite material for the lithium ion battery with excellent service performance is obtained.

Description

Silicon-carbon composite material for lithium ion battery and preparation method thereof
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a silicon-carbon composite material for a lithium ion battery with a surface coated with a modified polymer film and a preparation method thereof
Background
The theoretical lithium storage capacity of silicon exceeds 10 times of the capacity of a graphite material, but the silicon generates more than 300% volume change along with the insertion and extraction of lithium ions in the charging and discharging processes, so that the silicon falls off from a copper foil current collector; meanwhile, along with the volume expansion and contraction of silicon, the SEI film formed on the surface is broken continuously and consumes active substances, so that a new SEI film formed by the electrolyte is damaged in continuous circulation, the capacity of the battery is rapidly attenuated, and the cycle performance and the capacity of the battery are poor. Meanwhile, silicon has basically no conductivity, which is not beneficial to the exertion of lithium storage capacity. The problem that the cycle life of a silicon-based material is rapidly reduced can be effectively solved by commonly using nano-crystallization and compounding of the silicon material, and the conventional method for preparing the silicon-carbon composite negative electrode material by compounding nano silicon powder and graphite can improve the conductivity of the silicon material and relieve volume expansion.
However, when the graphite and the nano silicon powder are compounded, the nano silicon powder is easy to lose contact with the graphite due to the volume change in the charging and discharging processes, so that the capacity is not exerted, and therefore, how to further improve the electrochemical performance of the silicon-carbon composite anode material after the nano silicon powder and the graphite are compounded is a problem which needs to be solved urgently,
disclosure of Invention
In view of the above, the invention provides a silicon-carbon composite material for a lithium ion battery and a preparation method thereof, the preparation method is simple and efficient, and the obtained silicon-carbon composite material for the lithium ion battery is coated with a modified polymer film on the surface, so that the volume expansion of nano silicon-carbon powder can be effectively inhibited, and the cycle performance and the capacity of the lithium ion battery can be improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
the silicon-carbon composite material for the lithium ion battery is characterized by comprising a precursor core and a modified polymer coating layer, wherein the precursor core comprises nano silicon powder, a cracking carbon source and graphite powder, the modified polymer coating layer is made of a coating agent, and the coating agent comprises ethyl cellulose or polyvinylidene fluoride.
The beneficial effects of the preferred technical scheme are as follows: according to the silicon-carbon composite material for the lithium ion battery, disclosed by the invention, the surface of the silicon-carbon composite negative electrode material is coated with the layer of the modified polymer film with the obdurability, so that the volume expansion of nano silicon powder particles in the charging and discharging process can be reduced, the nano silicon powder particles are prevented from falling off from graphite particles, and the first efficiency and the cycling stability of the silicon-carbon composite negative electrode material can be improved; the cracking carbon source can tightly combine the nano silicon powder on the surface of the graphite particles, so that the stability of the silicon-carbon composite material is improved.
Preferably, the composition consists of the following components in parts by weight: 98-90% of precursor core and 2-10% of modified macromolecule coating layer.
Preferably, the precursor core comprises the following components in percentage by weight: 10% of nano silicon powder, 5% of cracking carbon source and 85% of graphite.
Preferably, the source of the lytic carbon comprises citric acid, glucose or sucrose.
The invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which is characterized by specifically adopting the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparing a precursor core: preparing a precursor core from nano silicon powder, a cracking carbon source and graphite powder;
(3) preparing a modified polymer coating layer: and coating the coating agent on the surface of the prepared precursor core to obtain a modified polymer coating layer, thus obtaining the carbon-silicon composite material for the lithium ion battery.
The beneficial effects of the preferred technical scheme are as follows: the preparation method disclosed by the invention is simple in process, the precursor core is prepared firstly, and then the modified polymer film is directly formed on the surface of the precursor core, so that the silicon-carbon composite material for the lithium ion battery can be obtained, the process flow is simplified, and the working efficiency can be improved.
Preferably, the step (2) specifically comprises the following steps:
(A) adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol for ultrasonic treatment to obtain a suspension;
(B) stirring the suspension obtained in the step (A), adding graphite powder, and uniformly mixing to obtain slurry;
(C) and (C) drying the slurry obtained in the step (B), and then adding the dried slurry into a vacuum carbonization furnace for carbonization treatment to obtain a precursor core.
The beneficial effects of the preferred technical scheme are as follows: the invention firstly carries out ultrasonic treatment to uniformly disperse the nano silicon powder and the cracking carbon source in the mixed solvent, so that the obtained suspension has uniform and stable properties; then adding graphite powder after stirring, which can improve the uniformity of the slurry and reduce the agglomeration of the nano silicon powder on the surface of the graphite particles; after drying, vacuum carbonization can be carried out to carbonize the cracking carbon source and improve the stability of the precursor core.
Preferably, the volume ratio of the deionized water to the alcohol in the mixed solvent is 50: 50-90: 10.
Preferably, the stirring speed in the step (B) is 1000-2000 r/min, and the stirring time is 0.5-1 h.
Preferably, the drying manner in the step (C) is spray drying, freeze drying or oven drying; the carbonization treatment is carried out for 2-5h under the vacuum condition and at the temperature of 600-.
Preferably, the step (3) specifically comprises the following steps:
A. dissolving the coating agent in the step (1) in an organic solvent, then adding the precursor core in the step (2), and uniformly stirring to obtain a mixed system;
B. and (3) stirring and heating the mixed system, drying, continuously heating until the coating agent is molten, adding the molten coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
The beneficial effects of the preferred technical scheme are as follows: according to the invention, the coating agent is dissolved in the organic solvent to form a mixed solution, so that coating can be realized under a liquid state condition, and the coating effect is more uniform; in addition, the invention can realize stable coating after the coating agent is melted, and rapidly cool to ensure that the polymer coated on the surface is rapidly shrunk to improve the coating stability, improve the performance and enhance the toughness.
Preferably, in the step A, the content of the coating agent in the solution is 0.8-4 wt.%, the stirring speed is 100-200 r/min, and the stirring time is 0.5-1 h; the organic solvent comprises alcohol, acetone, dimethylacetamide or N-methylpyrrolidone.
Preferably, in the step B, the temperature is increased to 170-310 ℃ to melt the coating agent.
According to the technical scheme, compared with the prior art, the silicon-carbon composite material for the lithium ion battery is provided, the modified polymer film with high toughness is coated on the surface of the silicon-carbon composite negative electrode material, so that the volume expansion of nano silicon powder particles in the charging and discharging process can be reduced, the nano silicon powder particles are prevented from falling off from graphite particles, and the first efficiency and the cycling stability of the silicon-carbon composite negative electrode material can be improved; meanwhile, the preparation method of the silicon-carbon composite material for the lithium ion battery is simple in preparation process and high in production efficiency.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is an SEM topography of a silicon-carbon composite anode material prepared in example 1 of the present invention;
FIG. 2 is an SEM topography of a silicon-carbon composite anode material prepared in comparative example 1 of the invention;
fig. 3 is a graph of capacity retention rate obtained by testing after negative electrode sheets made of the silicon-carbon composite materials prepared in examples 1 to 4 of the invention and comparative example 1 are assembled into a 2032 button cell.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of a precursor core and a modified polymer coating layer, wherein the precursor core comprises nano silicon powder, a cracking carbon source and graphite powder, the modified polymer coating layer is made of a coating agent, and the coating agent comprises ethyl cellulose or polyvinylidene fluoride.
The weight parts of the components are as follows: 98-90% of precursor core and 2-10% of modified macromolecule coating layer.
The precursor core comprises the following components in percentage by weight: 10% of nano silicon powder, 5% of cracking carbon source and 85% of graphite.
Wherein the cracking carbon source comprises citric acid, glucose or sucrose.
The embodiment of the invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparation of precursor core
(A) Adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol for ultrasonic treatment to obtain a suspension; the volume ratio of the deionized water to the alcohol in the mixed solvent is 50: 50-90: 10
(B) Stirring the suspension obtained in the step (A) at the rotating speed of 1000-2000 r/min for 0.5-1 h, then adding graphite powder, and uniformly mixing to obtain slurry;
(C) and (C) drying the slurry obtained in the step (B), adding the dried slurry into a vacuum carbonization furnace, and carbonizing at the temperature of 600-1000 ℃ for 2-5h under the vacuum condition to obtain a precursor core.
(3) Preparation of modified Polymer coating layer
A. Dissolving the coating agent in the step (1) in an organic solvent to obtain a solution with the coating agent content of 0.8-4 wt.%, adding the precursor core in the step (2), and stirring at the rotating speed of 100-200 r/min for 0.5-1 h to obtain a mixed system;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 170-310 ℃ to melt the coating agent, adding the molten coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
In order to further optimize the technical scheme, the drying mode in the step (C) is spray drying, freeze drying or drying.
In order to further optimize the technical scheme, the coating agent in the step A is added, and the stirring speed is as follows; the organic solvent comprises alcohol, acetone, dimethylacetamide or N-methylpyrrolidone.
Example 1
The embodiment 1 of the invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of 98% of a precursor core and 2% of a modified polymer coating layer, wherein the precursor core is prepared from 10% of nano silicon powder, 5% of a cracking carbon source and 85% of graphite powder, and the modified polymer coating layer is prepared from ethyl cellulose.
The embodiment 1 of the invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparation of precursor core
(A) Adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol to form a mixed solution containing 4 wt.% of nano silicon powder and 2 wt.% of citric acid, and then carrying out ultrasonic treatment to obtain a suspension; the volume ratio of the deionized water to the alcohol in the mixed solvent is 90: 10;
(B) stirring the suspension obtained in the step (A) at the rotating speed of 1000r/min for 1h, then adding graphite powder, and uniformly mixing to obtain slurry containing 34 wt.% of graphite powder;
(C) and (C) spray-drying the slurry obtained in the step (B), adding the slurry into a vacuum carbonization furnace, and carbonizing at 600 ℃ for 5 hours under a vacuum condition to obtain a precursor core.
(3) Preparation of modified Polymer coating layer
A. Dissolving ethyl cellulose in alcohol to obtain a solution with the ethyl cellulose content of 0.8 wt.%, then adding a precursor core, and stirring at the rotating speed of 100r/min for 1h to obtain a mixed system;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 170 ℃ to melt the coating agent, adding the coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
Example 2
The embodiment 2 of the invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of 98 wt.% of a precursor core and 2 wt.% of a modified polymer coating layer, wherein the precursor core is prepared from 10% of nano silicon powder, 5% of a cracking carbon source and 85% of graphite powder, and the modified polymer coating layer is prepared from polyvinylidene fluoride.
The embodiment 2 of the invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparation of precursor core
(A) Adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol to form a mixed solution containing 4 wt.% of nano silicon powder and 2 wt.% of citric acid, and then carrying out ultrasonic treatment to obtain a suspension; the volume ratio of the deionized water to the alcohol in the mixed solvent is 90: 10;
(B) stirring the suspension obtained in the step (A) at the rotating speed of 2000r/min for 0.5h, then adding graphite powder, and uniformly mixing to obtain slurry containing 34 wt.% of graphite powder;
(C) and (C) spray-drying the slurry obtained in the step (B), adding the slurry into a vacuum carbonization furnace, and carbonizing at 1000 ℃ for 2 hours under a vacuum condition to obtain a precursor core.
(3) Preparation of modified Polymer coating layer
A. Weighing 90% of the precursor core in the step (2) and 10% of polyvinylidene fluoride for later use; dissolving polyvinylidene fluoride in dimethylacetamide to obtain a solution with the polyvinylidene fluoride content of 4 wt.%, adding a precursor core, and stirring at the rotating speed of 200r/min for 0.5h to obtain a mixed system;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 250 ℃ to melt the coating agent, adding the coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
Example 3
The embodiment 3 of the invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of 95% of a precursor kernel and 5% of a modified polymer coating layer, wherein the precursor kernel is prepared from 10% of nano silicon powder, 5% of a cracking carbon source and 85% of graphite powder, and the modified polymer coating layer is prepared from polyvinylidene fluoride.
The embodiment 3 of the invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparation of precursor core
(A) Adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol to form a mixed solution containing 4 wt.% of nano silicon powder and 2 wt.% of citric acid, and then carrying out ultrasonic treatment to obtain a suspension; the volume ratio of the deionized water to the alcohol in the mixed solvent is 90: 10;
(B) stirring the suspension obtained in the step (A) at the rotating speed of 2000r/min for 0.5h, then adding graphite powder, and uniformly mixing to obtain slurry containing 34 wt.% of graphite powder;
(C) and (C) spray-drying the slurry obtained in the step (B), adding the slurry into a vacuum carbonization furnace, and carbonizing at 1000 ℃ for 2 hours under a vacuum condition to obtain a precursor core.
(3) Preparation of modified Polymer coating layer
A. Dissolving polyvinylidene fluoride in dimethylacetamide to obtain a solution with the polyvinylidene fluoride content of 2 wt.%, adding a precursor core, and stirring at the rotating speed of 150r/min for 0.5h to obtain a mixed system;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 300 ℃ to melt the coating agent, adding the coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
Example 4
The embodiment 4 of the invention discloses a silicon-carbon composite material for a lithium ion battery, which consists of 98% of a precursor core and 2% of a modified polymer coating layer, wherein the precursor core is prepared from 10% of nano silicon powder, 5% of a cracking carbon source and 85% of graphite powder, and the modified polymer coating layer is prepared from polyvinylidene fluoride.
The embodiment 4 of the invention also discloses a preparation method of the silicon-carbon composite material for the lithium ion battery, which specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent according to the silicon-carbon composite material for the lithium ion battery for later use;
(2) preparation of precursor core
(A) Adding the nano silicon powder and the cracking carbon source in the step (1) into a mixed solvent of deionized water and alcohol to form a mixed solution containing 4 wt.% of nano silicon powder and 2 wt.% of citric acid, and then carrying out ultrasonic treatment to obtain a suspension; the volume ratio of the deionized water to the alcohol in the mixed solvent is 90: 10;
(B) stirring the suspension obtained in the step (A) at the rotating speed of 2000r/min for 0.5h, then adding graphite powder, and uniformly mixing to obtain slurry containing 34 wt.% of graphite powder;
(C) and (C) spray-drying the slurry obtained in the step (B), adding the slurry into a vacuum carbonization furnace, and carbonizing at 1000 ℃ for 2 hours under a vacuum condition to obtain a precursor core.
(3) Preparation of modified Polymer coating layer
A. Dissolving polyvinylidene fluoride in dimethylacetamide to obtain a solution with the polyvinylidene fluoride content of 0.8 wt.%, adding a precursor core, and stirring at the rotating speed of 200r/min for 0.5h to obtain a mixed system;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 250 ℃ to melt the coating agent, adding the coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
Comparative example 1
The precursor core prepared in the step (2) of the example 1 is assembled into a 2032 button cell for testing the cycle life, the material performance data is shown in table 1, and the capacity retention rate curve is shown in fig. 3.
The silicon-carbon composite material prepared in the embodiment is prepared into a negative plate, and is assembled into a 2032 button cell for testing the cycle life, the material performance data is shown in table 1, and the capacity retention rate curve is shown in fig. 3. The method for testing the cycle performance of the battery comprises the following steps: the cycle performance was tested in one cycle by first discharging to 0.01v at a current density of 100mA/g, then discharging to 0.005v at a current of 10mA/g, standing for 3min, and then charging to 1.5v at a current density of 100 mA/g.
TABLE 1
Figure BDA0001852930940000091
As is evident from the data in table 1 above: the silicon-carbon composite material for the lithium ion battery prepared in the embodiments 1 to 4 can obviously improve the first reversible capacity and the first efficiency of the lithium ion battery, and can improve the cycle reversible capacity and the retention rate of the lithium ion battery and improve the cycle usability of the lithium ion battery.
In the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (1)

1. The preparation method of the silicon-carbon composite material for the lithium ion battery is characterized in that the silicon-carbon composite material consists of 90-98 wt% of a precursor core and 2-10 wt% of a modified polymer coating layer, wherein the precursor core is prepared from nano silicon powder, a cracking carbon source and graphite powder, the modified polymer coating layer is prepared from a coating agent, and the coating agent is ethyl cellulose or polyvinylidene fluoride;
the cracking carbon source is citric acid, glucose or sucrose;
the preparation method specifically comprises the following steps:
(1) weighing nano silicon powder, a cracking carbon source, graphite powder and a coating agent for later use;
(2) preparing a precursor core:
step (A): adding the nano silicon powder and the pyrolysis carbon source in the step (1) into a mixed solvent of deionized water and alcohol for ultrasonic treatment to obtain a suspension, wherein the volume ratio of the deionized water to the alcohol in the mixed solvent is 50: 50-90: 10, and the mass percentage of the nano silicon powder in the suspension is 4%;
step (B): stirring the suspension obtained in the step (A) at 1000-2000 r/min for 0.5-1 h, then adding graphite powder, and uniformly mixing to obtain slurry;
step (C): spray drying the slurry obtained in the step (B), and then adding the slurry into a vacuum carbonization furnace for carbonization treatment for 2-5h at the temperature of 600-1000 ℃ under the vacuum condition to obtain a precursor core;
(3) preparing a modified polymer coating layer: A. dissolving the coating agent in the step (1) in an organic solvent to obtain a solution, then adding the precursor core in the step (2), and stirring for 0.5-1 h at a speed of 100-200 r/min to obtain a mixed system; the content of the coating agent in the solution is 0.8-4 wt.%;
the organic solvent is acetone, dimethylacetamide or N-methylpyrrolidone;
B. and (3) stirring and heating the mixed system for drying, continuously heating to 170-310 ℃ to melt the coating agent, adding the molten coating agent into deionized water for quenching, and finally drying to obtain the silicon-carbon composite material for the lithium ion battery.
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Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101179123A (en) * 2006-11-09 2008-05-14 比亚迪股份有限公司 Method for producing anode of lithium ion battery
CN103346305A (en) * 2013-07-01 2013-10-09 华南师范大学 Preparation and application of lithium battery silicon-carbon composite material taking synthetic graphite as carrier
CN103887507A (en) * 2012-12-19 2014-06-25 三星Sdi株式会社 Negative electrode for rechargeable lithium battery, method of preparing the same and rechargeable lithium battery including the same
CN104466128A (en) * 2014-10-31 2015-03-25 山东玉皇新能源科技有限公司 PMMA-coated hollow tin alloy nanoparticles and preparation method and application thereof
CN104638240A (en) * 2015-02-06 2015-05-20 湖州创亚动力电池材料有限公司 Method for preparing lithium ion battery silicon carbon composite anode material and product prepared by method
CN105633368A (en) * 2015-12-31 2016-06-01 深圳市贝特瑞新能源材料股份有限公司 Negative electrode material of lithium ion battery and preparation method for negative electrode material
CN106549149A (en) * 2016-10-28 2017-03-29 浙江天能能源科技股份有限公司 A kind of preparation method and application of Si-C composite material
CN106848241A (en) * 2017-02-27 2017-06-13 苏州大学 A kind of preparation method of polymer overmold lithium ion battery electrode material
CN106876663A (en) * 2015-12-12 2017-06-20 北京好风光储能技术有限公司 A kind of electrode material carbon coating device and method
CN107658450A (en) * 2017-09-18 2018-02-02 江苏道赢科技有限公司 A kind of microcapsule-type silicon-carbon composite cathode material and its preparation method and application
CN107732192A (en) * 2017-09-30 2018-02-23 中国有色桂林矿产地质研究院有限公司 Used as negative electrode of Li-ion battery Si-C composite material and preparation method thereof
CN108461743A (en) * 2018-03-13 2018-08-28 成都新柯力化工科技有限公司 A kind of nickelic ternary electrode material of lithium battery that network is inlayed and preparation method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101201804B1 (en) * 2011-04-21 2012-11-15 삼성에스디아이 주식회사 Negative active for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101179123A (en) * 2006-11-09 2008-05-14 比亚迪股份有限公司 Method for producing anode of lithium ion battery
CN103887507A (en) * 2012-12-19 2014-06-25 三星Sdi株式会社 Negative electrode for rechargeable lithium battery, method of preparing the same and rechargeable lithium battery including the same
CN103346305A (en) * 2013-07-01 2013-10-09 华南师范大学 Preparation and application of lithium battery silicon-carbon composite material taking synthetic graphite as carrier
CN104466128A (en) * 2014-10-31 2015-03-25 山东玉皇新能源科技有限公司 PMMA-coated hollow tin alloy nanoparticles and preparation method and application thereof
CN104638240A (en) * 2015-02-06 2015-05-20 湖州创亚动力电池材料有限公司 Method for preparing lithium ion battery silicon carbon composite anode material and product prepared by method
CN106876663A (en) * 2015-12-12 2017-06-20 北京好风光储能技术有限公司 A kind of electrode material carbon coating device and method
CN105633368A (en) * 2015-12-31 2016-06-01 深圳市贝特瑞新能源材料股份有限公司 Negative electrode material of lithium ion battery and preparation method for negative electrode material
CN106549149A (en) * 2016-10-28 2017-03-29 浙江天能能源科技股份有限公司 A kind of preparation method and application of Si-C composite material
CN106848241A (en) * 2017-02-27 2017-06-13 苏州大学 A kind of preparation method of polymer overmold lithium ion battery electrode material
CN107658450A (en) * 2017-09-18 2018-02-02 江苏道赢科技有限公司 A kind of microcapsule-type silicon-carbon composite cathode material and its preparation method and application
CN107732192A (en) * 2017-09-30 2018-02-23 中国有色桂林矿产地质研究院有限公司 Used as negative electrode of Li-ion battery Si-C composite material and preparation method thereof
CN108461743A (en) * 2018-03-13 2018-08-28 成都新柯力化工科技有限公司 A kind of nickelic ternary electrode material of lithium battery that network is inlayed and preparation method

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