CN111509215A - Preparation method of high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material - Google Patents

Preparation method of high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material Download PDF

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CN111509215A
CN111509215A CN202010336787.4A CN202010336787A CN111509215A CN 111509215 A CN111509215 A CN 111509215A CN 202010336787 A CN202010336787 A CN 202010336787A CN 111509215 A CN111509215 A CN 111509215A
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熊永莲
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Yancheng Institute of Technology
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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
    • H01M4/38—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
    • 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
    • H01M4/62—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
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • 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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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 provides a preparation method of a high-first-efficiency long-cycle lithium battery negative electrode silicon carbon material. The lithium battery cathode silicon carbon material prepared by the invention has the advantages of high first efficiency and long cycle, and in addition, the preparation method is convenient to operate, simple and convenient in equipment and convenient for commercial popularization.

Description

Preparation method of high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material
Technical Field
The invention relates to the field of lithium batteries, in particular to the field of preparation of lithium battery cathode silicon-carbon materials.
Technical Field
At present, graphite is mainly used as a negative electrode material of a lithium battery, the theoretical capacity of the negative electrode material is 372mAh/g, but with the wide application of the lithium battery in daily life, the requirements on high power density and high energy density are increasingly highlighted. Compared with the silicon, the theoretical capacity of the silicon is 4200mAh/g, and the advantages of the silicon are self-evident, so that research and development of silicon-carbon negative electrode materials are carried out by various scientific research teams, but silicon is easy to agglomerate in the preparation process of the silicon-carbon negative electrode materials, and the defects of low cycle life and the like are caused. How to reduce the silicon agglomeration in the silicon-carbon cathode material has become a difficult point to be overcome in the industry.
Disclosure of Invention
The invention aims to provide a preparation method of a silicon-carbon material of a lithium battery cathode, and the silicon-carbon material prepared by the method has the advantages of high first efficiency and long cycle.
The preparation method of the silicon-carbon negative electrode material of the lithium ion battery comprises the following steps:
1. a preparation method of a high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material comprises the following steps:
a, adding industrial alcohol into a high-speed mixing, stirring and evaporating machine;
b, adding lauric acid with the graphite content of 0.1-0.5% into the industrial alcohol obtained in the step A, and adjusting the stirring time of a stirring and evaporating machine to be 0.5-1 h and the rotating speed to be 180-240 r/min;
c, adding graphite into the solution in the step B, and stirring for 1.5-2.5 h again at the rotating speed of 180-240 r/min;
d, according to the nano silicon slurry: adding nano silicon slurry into the solution obtained in the step C according to the proportion of graphite to be 25: 12-25: 27, wherein the median particle size of nano silicon is 40-80 nm, the solvent is industrial alcohol, the solid content is 8-12%, stirring for 2-4 h, and rotating speed is 180-240 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150-260 ℃, introducing nitrogen into the stirring and drying machine for protection in the heating process, controlling the nitrogen flow rate to be 8-16L/min, and controlling the rotation speed of the stirring and drying machine to be 180-240 r/min to form a silicon-carbon cathode material precursor;
f, transferring the silicon-carbon cathode material precursor obtained in the step E to a rotary furnace for roasting, heating to 800-900 ℃, introducing nitrogen into the rotary furnace for protection in the heating process, controlling the nitrogen flow rate to be 6-12L/min and the heating rate to be 5-10 ℃/min, controlling the nitrogen flow rate to be 6-8L/min in the heat preservation process, and preserving the heat for 2-4 h, then naturally cooling, and controlling the nitrogen flow rate to be 6-8L/min in the cooling process;
and G, sieving the material obtained in the step F by using a 300-mesh sieve to obtain the silicon-carbon material for the negative electrode of the lithium battery.
Drawings
FIG. 1 is an XRD of a silico-carbonaceous material for a negative electrode prepared in example 1 of the present invention;
FIG. 2 is a charge/discharge curve of a negative electrode prepared in example 1 of the present invention, which is made of a silicon carbon material and has a charging current of 0.1C;
FIG. 3 is a charging cycle curve at a constant current of 0.5C for a negative electrode prepared in example 1 of the present invention and made of a silicon carbon material;
Detailed Description
Example 1
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
and G, sieving the material obtained in the step F by using a 300-mesh sieve to obtain the silicon-carbon material for the negative electrode of the lithium battery.
FIG. 1 is an XRD of a silico-carbonaceous material for a negative electrode prepared in example 1 of the present invention;
FIG. 2 is a charging and discharging curve of a negative electrode prepared in example 1 of the present invention made of a silicon-carbon material with a charging voltage of 0.1C, wherein the gram capacity is 630mAh/g, and the first effect is 91%;
FIG. 3 is a charging cycle curve of a negative electrode prepared in example 1 of the present invention made of a silicon-carbon material with a charging current of 0.5C, wherein the first cycle capacity is 600.2mAh/g, and the gram capacity after 330 cycles is increased to 671.4mAh/g, which may be due to the fact that nano-silicon generates a new interface due to stress during repeated lithium intercalation and deintercalation, thereby increasing the amount of intercalated lithium;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 2
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
b, weighing 112.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 3
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 1h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min and 180r/min
F, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 4
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into industrial alcohol, stirring for 0.5h at the rotating speed of 240 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, stirring for 1.5h, and rotating at the speed of 240 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of the nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and the rotating speed is 240 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 240 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 5
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 2 hours at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of the nano-silicon is 40nm, the solvent is industrial alcohol with the purity of 99.99 percent, the solid content is 8 percent, stirring for 3 hours, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 6
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 4h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 7
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 260 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 8
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by using a rotary furnace, heating to 800 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 5 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.
Example 9
A preparation method of a silicon-carbon negative electrode material for a lithium ion battery specifically comprises the following steps:
weighing 85.14kg of industrial alcohol, adding into a high-speed mixing, stirring and evaporating machine;
weighing 22.5g of lauric acid, adding into the industrial alcohol, stirring for 0.5h at the rotating speed of 180 r/min;
c, weighing 22.5kg of graphite, adding the graphite into the solution obtained in the step B, and stirring for 1.5h at the rotating speed of 180 r/min;
d, adding 31.25kg of nano-silicon solution into the solution obtained in the step C, wherein the median particle size of nano-silicon is 40nm, the solvent is industrial alcohol, the solid content is 8%, stirring for 3h, and rotating speed is 180 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150 ℃, introducing nitrogen for protection, wherein the nitrogen flow rate is 8L/min, and the rotation speed is 180 r/min;
f, roasting the silicon-carbon cathode material precursor obtained in the step E by using a rotary furnace, heating to 900 ℃, wherein the nitrogen flow rate in the heating process is 6L/min, the heating rate is 10 ℃/min, the heat preservation process is 6L/min, the heat preservation is carried out for 4h, and the nitrogen flow rate is 6L/min during cooling;
mixing the prepared silicon-carbon material for the negative electrode with SP, CMC and SBR according to a mass ratio of 85:5:5:5, mixing the mixture with NMP to obtain slurry, uniformly coating the slurry on a copper foil, carrying out vacuum drying at 80 ℃ for 24 hours to obtain an electrode piece for buckling, then using a lithium piece as a counter electrode, using a L iPF6 four-component mixed solvent (EC: DMC: VC: FEC: 1:1:1) of 1.1 mol/L, using a polypropylene microporous membrane as a diaphragm, assembling a CR2025 type buckle type half cell in a vacuum glove box, discharging at a constant current of 0.1C to 5mV, discharging at a constant current of 0.02C to 5mV, charging at a constant current of 0.1C to 1.5V, and then adopting a 0.5C multiplying power for circulation.

Claims (1)

1. A preparation method of a high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material comprises the following steps:
a, adding industrial alcohol into a high-speed mixing, stirring and evaporating machine;
b, adding lauric acid with the graphite content of 0.1-0.5% into the industrial alcohol obtained in the step A, and adjusting the stirring time of a stirring and evaporating machine to be 0.5-1 h and the rotating speed to be 180-240 r/min;
c, adding graphite into the solution in the step B, and stirring for 1.5-2.5 h again at the rotating speed of 180-240 r/min;
d, according to the nano silicon slurry: adding nano silicon slurry into the solution obtained in the step C according to the proportion of graphite to be 25: 12-25: 27, wherein the median particle size of nano silicon is 40-80 nm, the solvent is industrial alcohol, the solid content is 8-12%, stirring for 2-4 h, and rotating speed is 180-240 r/min;
e, heating the solution obtained in the step D to dryness at the heating temperature of 150-260 ℃, introducing nitrogen into the stirring and drying machine for protection in the heating process, controlling the nitrogen flow rate to be 8-16L/min, and controlling the rotation speed of the stirring and drying machine to be 180-240 r/min to form a silicon-carbon cathode material precursor;
f, transferring the silicon-carbon cathode material precursor obtained in the step E to a rotary furnace for roasting, heating to 800-900 ℃, introducing nitrogen into the rotary furnace for protection in the heating process, controlling the nitrogen flow rate to be 6-12L/min and the heating rate to be 5-10 ℃/min, controlling the nitrogen flow rate to be 6-8L/min in the heat preservation process, and preserving the heat for 2-4 h, then naturally cooling, and controlling the nitrogen flow rate to be 6-8L/min in the cooling process;
and G, sieving the material obtained in the step F by using a 300-mesh sieve to obtain the silicon-carbon material for the negative electrode of the lithium battery.
CN202010336787.4A 2020-04-26 2020-04-26 Preparation method of high-first-efficiency long-cycle lithium battery negative electrode silicon-carbon material Pending CN111509215A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103904307A (en) * 2012-12-24 2014-07-02 宁波杉杉新材料科技有限公司 Silicon-carbon composite material, preparation method and application thereof
CN106848258A (en) * 2017-03-27 2017-06-13 深圳市沃特玛电池有限公司 A kind of graphitized carbon cathode material preparation method
CN109216690A (en) * 2018-11-01 2019-01-15 湖北融通高科先进材料有限公司 A kind of high capacity Si-C composite material and preparation method thereof and lithium ion battery
CN109216689A (en) * 2018-10-25 2019-01-15 湖北融通高科先进材料有限公司 A kind of Si-C composite material and preparation method thereof and lithium ion battery
CN109461890A (en) * 2017-09-06 2019-03-12 丰域科技（北京）有限公司 Silicon-carbon cathode material, preparation method and lithium ion battery

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103904307A (en) * 2012-12-24 2014-07-02 宁波杉杉新材料科技有限公司 Silicon-carbon composite material, preparation method and application thereof
CN106848258A (en) * 2017-03-27 2017-06-13 深圳市沃特玛电池有限公司 A kind of graphitized carbon cathode material preparation method
CN109461890A (en) * 2017-09-06 2019-03-12 丰域科技（北京）有限公司 Silicon-carbon cathode material, preparation method and lithium ion battery
CN109216689A (en) * 2018-10-25 2019-01-15 湖北融通高科先进材料有限公司 A kind of Si-C composite material and preparation method thereof and lithium ion battery
CN109216690A (en) * 2018-11-01 2019-01-15 湖北融通高科先进材料有限公司 A kind of high capacity Si-C composite material and preparation method thereof and lithium ion battery

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Application publication date: 20200807