CN110660989B - Silicon-based Si-B-C negative electrode material prepared from calcium carbide co-reduction silicon oxide and boron-containing oxide and preparation method and application thereof - Google Patents

Silicon-based Si-B-C negative electrode material prepared from calcium carbide co-reduction silicon oxide and boron-containing oxide and preparation method and application thereof Download PDF

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CN110660989B
CN110660989B CN201910925675.XA CN201910925675A CN110660989B CN 110660989 B CN110660989 B CN 110660989B CN 201910925675 A CN201910925675 A CN 201910925675A CN 110660989 B CN110660989 B CN 110660989B
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calcium
boron
silicon
silicon oxide
chloride
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CN110660989A (en
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谢宏伟
董函晴
王锦霞
尹华意
宋秋实
宁志强
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Northeastern University China
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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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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

A silicon-based Si-B-C cathode material prepared from calcium carbide co-reduction silicon oxide and boron-containing oxide, a preparation method and application thereof belong to the field of preparation of battery cathode materials. The method takes calcium carbide, silicon oxide and boron-containing oxide as raw materials, and silicon-based Si-B-C negative electrode material synthesis is carried out in calcium chloride-based molten salt. The method can control the reaction rate and the energy release by adjusting the reaction parameters, and promote the reaction to effectively proceed. The prepared silicon-based Si-B-C negative electrode material has moderate particle size, and the prepared lithium ion battery has good specific capacity and cycle performance, the synthesis method is low in cost, and the synthesis process is simple to operate.

Description

Silicon-based Si-B-C negative electrode material prepared from calcium carbide co-reduction silicon oxide and boron-containing oxide and preparation method and application thereof
Technical Field
The invention relates to the field of preparation of battery cathode materials, in particular to a silicon-based Si-B-C cathode material prepared from calcium carbide co-reduction silicon oxide and boron-containing oxide, and a preparation method and application thereof.
Background
Lithium ion batteries are widely used because of their advantages of high energy density, long cycle life, no memory effect, etc. With the development of new energy vehicles and new energy power generation technologies, lithium ion power batteries for vehicles and lithium ion batteries for energy storage become urgent needs. The current commercialized lithium ion battery cathode material is graphite, the theoretical specific capacity of the graphite is only 372mAh/g, and the requirements of high-performance and high-capacity lithium ion batteries are difficult to meet. The silicon material becomes the focus of research due to the large theoretical specific capacity of 4200 mAh/g. But it suffers from volume expansion effects and lower conductivity, severely limiting its capacity-cycling performance.
At present, the methods for reducing the volume expansion of the silicon negative electrode material of the lithium ion battery are nano, nano porous and nano doping modification. Research shows that the silicon particles with the particle size of 100-150 nm have good electrochemical performance, but the current nanocrystallization cost is high and the scale amplification is not easy. In addition, the problem of volume expansion of the silicon negative electrode material of the lithium ion battery is reduced by nano treatment, and meanwhile, a coating treatment method is required to relieve side effects caused by nano treatment. The coating treatment method can buffer the stress generated by volume expansion, reduce the capacity loss of the nano silicon caused by nanocrystallization, improve the conductivity among particles and improve the cycle performance. Among them, carbon coating is one of effective coating treatment means. However, most of the existing silicon-carbon composites are prepared by simply mechanically mixing silicon particles and carbon, or by dispersing silicon nanoparticles in an organic carbon source such as phenol resin, PVA, citric acid, stearic acid, glucose, sucrose, polyvinyl alcohol, polyvinyl chloride, or polyethylene glycol and calcining and coating the mixture. The amorphous carbon formed after calcination isolates the contact between silicon and electrolyte, improves the stability of the material, but still has the problems that silicon particles are difficult to agglomerate and disperse, the conductivity is insufficient, the ohmic polarization is easy to cause and the like. Meanwhile, the preparation process of the silicon-carbon composite material is complex in process and high in production cost.
In fact, boron can intercalate into the silicon lattice to widen the silicon interplanar spacing, which is beneficial to alleviate the expansion problem of silicon after intercalation with lithium. Moreover, boron is embedded in the silicon lattice, which not only solves the problem of expansion, but also improves the electrical conductivity of silicon. The problems of poor cycle performance of the silicon cathode material of the lithium ion battery and the like are solved. The classic documents are: inorg, chem, 2019,58,4592-4599 and the like use metal magnesium to reduce boron oxide and silicic acid at 700 ℃ to form boron oxide-silicon dioxide after uniformly mixing, thereby preparing the boron-containing silicon lithium ion battery cathode material. Magnesium is a strong reducing agent, reduction is an exothermic reaction, a large amount of heat released in the reaction process can sinter oxide raw materials into large particles, the reaction is not favorably and effectively carried out, the production control is not favorably carried out, and the consumption of active and expensive metal magnesium is large. The method has the problems of high cost, complex operation, uneven distribution of Si and boron, large particle size of silicon products and the like.
Some methods have been to utilize silicon-calcium alloy to directly reduce aluminum chloride (typically: NanoResearch2018,11(12): 6294-. However, the silicon-calcium alloy is also a strong reducing agent, the reduction is an exothermic reaction, and a large amount of heat released in the reaction process can cause the silicon-calcium alloy to be sintered into large particles, so that the reaction is not easy to effectively carry out and control.
In summary, if a Si-B-C structure in which boron-dissolved silicon is embedded in a grid formed by carbon distribution can be constructed, not only can the large theoretical specific capacity of silicon be utilized, but also the problem of expansion of the silicon after lithium is embedded can be alleviated, and the conductivity can be significantly improved, which is beneficial to improving the overall performance of the lithium ion battery.
Disclosure of Invention
The invention provides a silicon-based Si-B-C negative electrode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide, and a preparation method and application thereof. The method can control the reaction rate and the energy release by adjusting the reaction parameters, and promote the reaction to effectively proceed. The prepared silicon-based Si-B-C negative electrode material has moderate particle size, and the prepared lithium ion battery has good specific capacity and cycle performance, the synthesis method is low in cost, and the synthesis process is simple to operate.
The invention is realized by the following technical scheme:
the invention relates to a preparation method of a silicon-based Si-B-C negative electrode material prepared from calcium carbide co-reduced silicon oxide and boron-containing oxide, which comprises the following steps:
step 1: preparation of
(1) Respectively drying the silicon oxide, the boron-containing oxide and the molten salt raw material, and removing water; wherein the molten salt is calcium chloride-based molten salt; the silicon oxide is one or two of silicon oxide or calcium silicate; the boron-containing oxide is boron oxide and borax (Na)2B4O7·10H2O), calcium borate (xCaO. yB)2O3.nH2O), magnesium borate (Mg)2B2O5) Potassium borate (K)2B4O7·5H2O) or a mixture of more than one of O);
(2) under the protection of inert gas, according to the stoichiometric ratio of reaction, respectively grinding the raw materials of calcium carbide-silicon oxide, calcium carbide-boron-containing oxide and molten salt until the materials are uniform, uniformly mixing, and sealing the obtained mixed material;
(3) placing the mixed material in an embedded crucible of a reactor, and sealing;
(4) introducing inert gas into the sealed reactor, maintaining the inert atmosphere, ensuring positive pressure in the reactor, and raising the temperature of the reactor while introducing the inert gas;
step 2: synthesis of
After the temperature of the reactor is raised to the synthesis temperature, keeping the temperature for 1-5 hours to obtain a product after reaction; wherein the synthesis temperature is 530-900 ℃;
and step 3:
and placing the product after reaction in a cooling container for cooling, grinding, washing with hydrochloric acid to remove molten salt, filtering, washing with water, and drying to obtain the silicon carbide co-reduction silicon oxide and the silicon-based Si-B-C negative electrode material prepared from the boron-containing oxide.
In the step 1(1), the particle size of the calcium carbide is 500 mu m-3 mm.
In the step 1(1), the calcium chloride-based molten salt is one of calcium chloride, calcium chloride-sodium chloride, calcium chloride-potassium chloride and calcium chloride-sodium chloride-potassium chloride, wherein the calcium chloride-based molten salt and the calcium chloride are main salts.
In the step 1(1), the drying process comprises: and (3) placing the raw materials in a high-temperature vacuum drying furnace, drying for 10-15 h at the temperature of 300-400 ℃ and under the pressure of-0.1 MPa, and removing adsorbed water and crystal water to obtain a dry molten salt raw material, a dry silicon oxide and a dry boron-containing oxide.
In the step 1(2), the inert gas is one of nitrogen, argon or a nitrogen-argon mixed gas.
In the step 1(2), when the silicon oxide contains silicon oxide and the boron-containing oxide contains boron oxide, the method is as followsMolar ratio, calcium carbide (CaC)2): silicon oxide (SiO)2) (2-2.5): 1, calcium carbide (CaC)2): boron oxide (B)2O3) (3-3.5): 1, silicon oxide (SiO)2): boron oxide (B)2O3) (2-10): 1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide and 3 times of boron oxide is more than or equal to 10: 3.
In the step 1(2), calcium carbide (CaC) is added to the silicon oxide in a molar ratio when the silicon oxide contains calcium silicate and the boron-containing oxide contains boron oxide2): calcium silicate (CaSiO)3) (2-2.5): 1, calcium carbide (CaC)2): boron oxide (B)2O3) (3-3.5): 1, calcium silicate (CaSiO)3): boron oxide (B)2O3) (2-10): 1, calcium chloride in calcium chloride-based molten salt: calcium silicate + boron oxide is more than or equal to 10: 1.
In the step 1(2), when the silicon oxide contains silicon oxide and the boron-containing oxide contains calcium borate, calcium borate CaB is used2O4By way of example, calcium carbide (CaC) in molar ratio2): silicon oxide (SiO)2) (2-2.5): 1, calcium carbide (CaC)2): calcium borate (CaB)2O4) (3-3.5): 1, silicon oxide (SiO)2): calcium borate (CaB)2O4) (2-10): 1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide to 4 times of calcium borate is more than or equal to 10: 3.
In the step 1(2), when the silicon oxide contains calcium silicate and the boron-containing oxide contains calcium borate, calcium borate CaB2O4By way of example, calcium carbide (CaC) in molar ratio2): calcium silicate (CaSiO)3) (2-2.5): 1, calcium carbide (CaC)2): calcium borate (CaB)2O4) (3-3.5): 1, calcium silicate (CaSiO)3): calcium borate (CaB)2O4) (2-10): 1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 4 times of boron oxide are more than or equal to 10: 3.
In the step 1(2), when the silicon oxide contains silicon oxide and the boron-containing oxide contains borax, calcium carbide (CaC) is added according to molar ratio2): silicon oxide (SiO)2) (2-2.5): 1, calcium carbide (CaC)2): borax (Na)2B4O7) (6-10): 1, silicon oxide (SiO)2): borax (Na)2B4O7) (4-20): 1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide and 8 times of borax is more than or equal to 10: 3.
In the step 1(2), calcium carbide (CaC) is added to the silicon oxide in a molar ratio when the silicon oxide contains calcium silicate and the boron-containing oxide contains borax2): calcium silicate (CaSiO)3) (2-2.5): 1, calcium carbide (CaC)2): borax (Na)2B4O7) (6-10): 1, calcium silicate (CaSiO)3): borax (Na)2B4O7) (4-20): 1, calcium chloride in calcium chloride-based molten salt: more than or equal to 10:3 of 3 times of calcium silicate and 8 times of borax.
In the step 1(2), when the silicon oxide contains silicon oxide and the boron-containing oxide contains magnesium borate, calcium carbide (CaC) is added according to molar ratio2): silicon oxide (SiO)2) (2-2.5): 1, calcium carbide (CaC)2): magnesium borate (Mg)2B2O5) (3-3.5): 1, silicon oxide (SiO)2): magnesium borate (Mg)2B2O5) (2-10): 1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide to 4 times of magnesium borate is more than or equal to 10: 3.
In the step 1(2), when the silicon oxide contains calcium silicate and the boron-containing oxide contains magnesium borate, calcium carbide (CaC) is added according to the molar ratio2): calcium silicate (CaSiO)3) (2-2.5): 1, calcium carbide (CaC)2): magnesium borate (Mg)2B2O5) (3-3.5): 1, calcium silicate (CaSiO)3): magnesium borate (Mg)2B2O5) (2-10): 1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 4 times of magnesium borate are more than or equal to 10: 3.
In the step 1(2), when the silicon oxide contains silicon oxide and the boron-containing oxide contains potassium borate, calcium carbide (CaC) is added according to molar ratio2): silicon oxide (SiO)2) (2-2.5): 1, calcium carbide (CaC)2): potassium borate (K)2B4O7) (6-10): 1, silicon oxide (SiO)2): boronPotassium salt (K)2B4O7) (4-20): 1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide to 8 times of potassium borate is more than or equal to 10: 3.
In the step 1(2), calcium carbide (CaC) is added to the silicon oxide in a molar ratio when the silicon oxide contains calcium silicate and the boron-containing oxide contains potassium borate2): calcium silicate (CaSiO)3) (2-2.5): 1, calcium carbide (CaC)2): potassium borate (K)2B4O7) (6-10): 1, calcium silicate (CaSiO)3): potassium borate (K)2B4O7) (4-20): 1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 8 times of potassium borate are more than or equal to 10: 3.
In the step 1(3), the embedded crucible is a graphite crucible or a nickel crucible.
In the step 1(4), the inert gas is argon or argon-nitrogen mixed gas, and when the inert gas is argon-nitrogen mixed gas, the volume ratio of argon: the nitrogen is more than or equal to 1: 1.
In the step 2, the reactor is heated by a resistance wire furnace, and the heating rate of heating to the synthesis temperature is 3-10 ℃/min.
In the step 2, the synthesis temperature is higher than the melting temperature of the molten salt raw material plus (10-20) DEG C.
In the step 2, after the temperature of the reactor is raised to the synthesis temperature, the temperature is kept constant, the stirring paddle can be inserted into the molten salt, stirring is maintained in the constant temperature process, and the rotating speed v of the stirring paddle is more than 0 and less than or equal to 700 r/min.
In the step 2, the stirring paddle is completely immersed in the molten salt, and the stirring paddle is driven to rotate by a frequency modulation motor.
In the step 3, the cooling container is a stainless steel container.
In the step 3, after the reaction product is discharged out of the reactor, the reactor is sealed, and simultaneously, the resistance wire furnace is cooled to room temperature, and the introduction of inert gas is stopped.
In the step 3, a mortar is used for grinding.
In the step 3, the hydrochloric acid is 0.1-0.2 mol/L hydrochloric acid.
In the step 3, the drying is vacuum drying at 50-80 ℃.
A silicon-based Si-B-C cathode material prepared from calcium carbide co-reduced silicon oxide and boron-containing oxide is prepared by the preparation method.
The particle diameter of the silicon-based Si-B-C negative electrode material prepared from the calcium carbide co-reduction silicon oxide and the boron-containing oxide is 50nm-50 mu m; when Si-B-C is statically synthesized, the particle size of the product particles is 5-50 μm; when the Si-B-C is synthesized by stirring, the particle size of the product particles is 50nm-500 nm.
An application of a silicon-based Si-B-C cathode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is used as a cathode material of a lithium ion battery.
The negative electrode material comprises the calcium carbide co-reduced silicon oxide and a silicon-based Si-B-C negative electrode material prepared from a boron-containing oxide.
The electrode plate comprises the anode material, and the anode material further comprises a binder, a conductive agent and a solvent.
A lithium ion battery comprises the electrode slice and a statically synthesized silicon-based Si-B-C negative electrode material, and the first charge-discharge coulombic efficiency of the lithium ion battery>80 percent, preferably 82 to 90 percent, and the first discharge reaches 2700 mAh/g; at 0.1 A.g-1Current density cycle 400 cycles with a reversible specific cycle capacity of>1400mAh/g, preferably 1450-1610 mAh/g; stirring synthesized silicon-based Si-B-C anode material with first charge-discharge coulombic efficiency>75 percent, preferably 77 to 85 percent, and the first discharge reaches 2500 mAh/g; at 0.1 A.g-1Current density is cycled for 500 cycles, and the reversible cycle specific capacity is>1400mAh/g, preferably 1430-1600 mAh/g.
The invention relates to a silicon-based Si-B-C cathode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide, a preparation method and application thereof, wherein the fused salt comprises the following chemical reaction equations:
thermodynamic calculations show that: chemical reaction 2CaC2+SiO2＝2CaO+Si+4C；2CaC2+CaSiO3＝3CaO+Si+4C；3CaC2+B2O3＝3CaO+2B+6C；3CaC2+Mg2B2O5＝6C+2B+3CaO+2MgO，3CaC2+CaB2O4＝4CaO+2B+6C；CaCl2+6CaC2+Na2B4O7＝12C+4B+7CaO+2NaCl；CaCl2+6CaC2+K2B4O7The research shows that calcium carbide has certain solubility in calcium chloride, so that the Si-B-C negative electrode material is synthesized by taking calcium carbide, silicon oxide and boron-containing oxide as raw materials in static or stirring calcium chloride-based molten salt, the particle size is controllable, the reaction can be accelerated, the prepared calcium oxide can be dissolved in the molten salt, the reaction can be accelerated, and the product and the molten salt are effectively separated, and the method can control the reaction rate, control the energy release and promote the reaction to effectively progress. The prepared silicon-based Si-B-C negative electrode material has a moderate particle size, and the prepared lithium ion battery has good first charge-discharge coulombic efficiency, high first discharge specific capacity and good cycle performance. The preparation cost is low, and the synthetic process is simple to operate.
The invention regulates and controls the reaction of calcium carbide, silicon oxide and boron-containing oxide, the reaction of calcium carbide and boron-containing oxide and the generation process of a product Si-B-C material by regulating and controlling the salt composition and proportion, the rotating speed of a stirring paddle, the synthesis temperature and the synthesis time. The reaction rate is controlled, the uniform distribution of silicon, boron and carbon in the Si-B-C product and the control of the particle size are promoted, the volume expansion in the silicon-lithium alloying process of the lithium ion battery cathode material is effectively relieved and buffered, the conductivity of the silicon material is improved, and the electrochemical performance is improved. The method utilizes low-cost calcium carbide, silicon oxide and boron-containing oxide as raw materials to synthesize the materials in the calcium chloride-based molten salt, realizes the preparation of the Si-B-C cathode material of the lithium ion battery with low cost and regulation, and has simple operation process. The prepared silicon-based Si-B-C negative electrode material has the advantages of moderate silicon particle size, good conductivity, good specific capacity and good cycle performance.
Detailed Description
The present invention will be described in further detail with reference to examples.
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are only for the purpose of the present invention and are not intended to limit the scope of the present invention. It should be understood that various changes and modifications can be made by those skilled in the art after reading the disclosure of the present invention, and equivalents fall within the scope of the appended claims.
In the embodiment of the invention, the raw materials and equipment are commercially available and the purity is analytically pure or higher unless otherwise specified; specifically, the adopted calcium carbide, silicon oxide and boron-containing oxide are commercial products, and the purity is analytical purity. The adopted calcium carbide is a commercial product, and the purity is industrial grade. The purity of various chloride salts of the calcium chloride-based salt used was analytical grade. The ceramic mortar, graphite or nickel crucible used are commercially available products.
Various chloride salts of the calcium chloride-based salt adopted in the embodiment of the invention are molten salts, and the operation temperature is controlled to be 530-900 ℃.
In the embodiment of the invention, the gas outlet of the reactor extends to the lower part of the liquid level in the water tank outside the reactor through the pipeline, and bubbles emerge when argon gas continuously circulates.
In the embodiment of the invention, various chloride salts of calcium chloride-based salt and boron-containing oxide containing crystal water are dried to remove adsorbed water and crystal water, and the various chloride salts of calcium chloride-based salt and the boron-containing oxide containing crystal water are placed in a high-temperature vacuum drying furnace and dried for 10-15 hours at the temperature of 300-400 ℃ and under the pressure of-0.1 MPa to remove adsorbed water and crystal water.
In the embodiment of the invention, the material in the reactor is heated by placing the reactor in a resistance wire furnace.
Example 1
A preparation method of a silicon-based Si-B-C negative electrode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide comprises the following steps:
(1) drying silicon oxide, boron oxide and calcium chloride to remove adsorbed water and crystal water;
(2) under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 1.5g +/-0.1 g of boron oxide is weighed, and the calcium carbide-boron oxide is obtained by uniformly mixing and grinding;
(3) under the protection of inert gas, weighing 4.3g +/-0.1 g of calcium carbide, weighing 2.7g +/-0.1 g of silicon oxide, mixing and grinding uniformly to obtain calcium carbide-silicon oxide;
(4) under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride is weighed and uniformly ground;
(5) mixing calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride to obtain mixed salt, and sealing;
(6) the mixed salt is put into a graphite crucible embedded in the reactor, and the reactor cover is sealed.
(7) Introducing inert gas-argon gas from a gas inlet of the reactor cover, and discharging the inert gas from a gas outlet of the reactor cover to ensure that the interior of the reactor is at positive pressure;
(8) heating the resistance wire furnace;
(9) heating the reactor to 800 ℃ at the heating rate of 5 ℃/min, melting calcium chloride to form molten salt, and reacting for 5 hours to obtain a reacted product;
(10) heating to discharge salt;
(11) after the salt in the salt outlet pipe is melted, the product after reaction flows out from the salt outlet by gravity and is stored in a stainless steel container for cooling.
(12) A small amount of reacted products are left in the salt outlet pipe, the salt outlet pipe is stopped being heated, and the residual reacted products are cooled and automatically sealed at a salt outlet;
(13) removing the cooled salt from the stainless steel container and grinding; desalting with 0.1mol/L hydrochloric acid, and filtering; washing the filtered product with deionized water; vacuum drying at 60 ℃ to obtain a silicon-based Si-B-C cathode material, and sealing for later use;
(14) and preparing the prepared silicon-based Si-B-C negative electrode material into a lithium ion battery negative electrode, and carrying out electrochemical test.
Example 2
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (9), in the molten salt reaction process, the reaction time is 3 h; the other ways are the same.
Example 3
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (9), in the molten salt reaction process, the reaction time is 1 h; the other ways are the same.
Example 4
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-boron oxide, calcium carbide-silicon oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 4 hours; the other ways are the same.
Example 5
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 4, and is different from the following steps:
(1) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 2 hours; the other ways are the same.
Example 6
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride is weighed, 7.4g +/-0.1 g of potassium chloride is weighed, and the calcium chloride-potassium chloride is obtained after uniform grinding;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 5 hours; the other ways are the same.
Example 7
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 6, and is different from that of example 6 in that:
(1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 3 hours; the other ways are the same.
Example 8
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 6, and is different from that of example 6 in that:
(1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 1 h; the other ways are the same.
Example 9
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride, potassium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0 +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the reaction time is 4 hours; the other ways are the same.
Example 10
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 9, except that:
(1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the reaction time is 2 hours; the other ways are the same.
Example 11
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), calcium silicate, boron oxide and calcium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (3), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed; the other ways are the same.
Example 12
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 11, except that:
(1) in the step (9), calcium chloride is melted to form molten salt, and the reaction time is 3 hours; the other ways are the same.
Example 13
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 11, except that:
(1) in the step (9), calcium chloride is melted to form molten salt, and the reaction time is 1 h; the other ways are the same.
Example 14
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 11, except that:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and uniformly ground to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 4 hours; the other ways are the same.
Example 15
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 14, except that:
(1) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 2 hours; the other ways are the same.
Example 16
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 11, except that:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride is weighed, 7.4g +/-0.1 g of potassium chloride is weighed, and the calcium chloride-potassium chloride is obtained after uniform grinding;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 5 hours; the other ways are the same.
Example 17
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 16, except that:
(1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 3 hours; the other ways are the same.
Example 18
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 16, except that:
(1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 1 h; the other ways are the same.
Example 19
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 11, except that:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride, potassium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and uniformly ground to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the reaction time is 4 hours; the other ways are the same.
Example 20
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 19 except that:
(1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the reaction time is 2 hours; the other ways are the same.
Example 21
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), silicon oxide, calcium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 4.3g of plus or minus 0.1g of calcium carbide and 2.8g of plus or minus 0.1g of calcium borate are weighed and mixed and ground uniformly to obtain calcium carbide-calcium borate;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed; the other ways are the same.
Example 22
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 21, except that:
(1) in the step (9), the reaction time is 3 h; the other ways are the same.
Example 23
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 21, except that:
(1) in the step (9), the reaction time is 1 h; the other ways are the same.
Example 24
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 21, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 25
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 24 except that:
(1) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 2 hours;
the other ways are the same.
Example 26
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 21, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 7.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
the other ways are the same.
Example 27
A method for preparing a silicon-based Si-B-C negative electrode material by using a calcium carbide co-reduced silicon oxide and a boron-containing oxide, which is similar to example 26, except that: (1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 3 hours; the other ways are the same.
Example 28
A method for preparing a silicon-based Si-B-C negative electrode material by using a calcium carbide co-reduced silicon oxide and a boron-containing oxide, which is similar to example 26, except that: (1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 1 hour; the other ways are the same.
Example 29
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 21, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride, sodium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 40.0g +/-0.1 g of sodium chloride and 7.4g +/-0.1 g of potassium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-sodium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-sodium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 30
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 29, except that:
(1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-sodium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 2 hours; the other ways are the same.
Example 31
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), calcium silicate, calcium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 4.3g of plus or minus 0.1g of calcium carbide and 2.8g of plus or minus 0.1g of calcium borate are weighed and mixed and ground uniformly to obtain calcium carbide-calcium borate;
(3) in the step (3), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(4) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed; the other ways are the same.
Example 32
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 31, except that:
(1) in the step (9), the reaction time is 3 h; the other ways are the same.
Example 33
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 31, except that:
(1) in the step (9), the reaction time is 1 h; the other ways are the same.
Example 34
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 31, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 35
A method for preparing a silicon-based Si-B-C negative electrode material by using a calcium carbide co-reduced silicon oxide and a boron-containing oxide, which is similar to example 34, except that:
(1) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 2 hours;
the other ways are the same.
Example 36
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 31, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 7.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
the other ways are the same.
Example 37
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 36 except that: (1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 3 hours; the other ways are the same.
Example 38
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 36 except that: (1) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 1 hour; the other ways are the same.
Example 39
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 31, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0g +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 40
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 39, except that: (1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 2 hours; the other ways are the same.
EXAMPLE 41
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), calcium silicate, borax and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 6.5g +/-0.1 g of calcium carbide is weighed, 2.3g +/-0.1 g of borax is weighed, and the calcium carbide-borax is obtained after uniform mixing and grinding;
(3) in the step (3), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(4) in the step (4), 140.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(5) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(6) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours; the other ways are the same.
Example 42
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), calcium silicate, borax, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 90.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 43
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), calcium silicate, borax, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 15.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 44
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), calcium silicate, borax, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride, 15.4g +/-0.1 g of potassium chloride and 90.0g +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 45
The preparation method of the silicon-based Si-B-C anode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide is the same as that in example 1, and is different from the following steps:
(1) in the step (1), silicon oxide, borax and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 6.5g +/-0.1 g of calcium carbide is weighed, 2.3g +/-0.1 g of borax is weighed, and the calcium carbide-borax is obtained after uniform mixing and grinding;
(3) in the step (3), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide and 2.7g +/-0.1 g of silicon oxide are weighed and mixed and ground uniformly to obtain calcium carbide-silicon oxide;
(4) in the step (4), 180.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(5) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride to obtain mixed salt, and sealing;
(6) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours; the other ways are the same.
Example 46
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), silicon oxide, borax, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 180.0g +/-0.1 g of calcium chloride and 120.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 47
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), silicon oxide, borax, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, weighing 180.0g +/-0.1 g of calcium chloride, weighing 22.4g +/-0.1 g of potassium chloride, mixing and grinding uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-potassium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 48
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 41, except that:
(1) in the step (1), silicon oxide, borax, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, weighing 180.0g +/-0.1 g of calcium chloride, 22.4g +/-0.1 g of potassium chloride and 120.0g +/-0.1 g of sodium chloride, mixing and grinding uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-potassium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 49
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 48 except that: (1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 3 hours; the other ways are the same.
Example 50
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 48 except that: (1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 2 hours; the other ways are the same.
Example 51
A preparation method of a silicon-based Si-B-C negative electrode material prepared by calcium carbide co-reduction silicon oxide and boron-containing oxide comprises the following steps:
(1) drying silicon oxide, boron oxide and calcium chloride, and removing adsorbed water and crystal water;
(2) under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 2.7g +/-0.1 g of silicon oxide is weighed, and the calcium carbide-silicon oxide is obtained after uniform grinding;
(3) under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 1.6g +/-0.1 g of boron oxide is weighed, and the calcium carbide-boron oxide is obtained after uniform grinding;
(4) under the protection of inert gas, 50.0g +/-0.1 g of calcium chloride is weighed and uniformly ground;
(5) mixing calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride, and sealing in a self-sealing bag;
(6) the mixed salt is loaded into a crucible embedded in the reactor, and the reactor cover is sealed.
(7) Introducing inert gas from a gas inlet of the reactor cover, and discharging the inert gas from a gas outlet of the reactor cover to ensure positive pressure in the reactor;
(8) heating the resistance wire furnace;
(9) heating the reactor to 800 ℃ at the heating rate of 6 ℃/min, melting calcium chloride to form molten salt, preserving heat for 5 hours,
(10) inserting a stirring paddle;
(11) rotating the stirring paddle, wherein the stirring speed is 700r/min, and continuously stirring in the heat preservation process, wherein the stirring time is the same as the heat preservation time;
(12) stopping stirring, and lifting away from the stirring paddle;
(13) a salt outlet pipe of the heating reactor;
(14) after the salt in the salt outlet pipe is melted, the salt flows out from the salt outlet by gravity and is stored in a stainless steel container for cooling.
(15) A small amount of salt is left in the salt outlet pipe, the salt outlet pipe is stopped being heated, and the salt outlet is automatically sealed after the residual salt is cooled;
(16) removing the cooled salt from the stainless steel container and grinding; desalting with 0.1mol/L hydrochloric acid, and filtering; washing the filtered product with deionized water; drying in a vacuum drying oven at 50 ℃ to obtain a silicon-based Si-B-C negative electrode material, and sealing for later use;
(17) and preparing the prepared silicon-based Si-B-C negative electrode material into a lithium ion battery negative electrode for electrochemical test.
Example 52
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that: (1) in the step (11), the stirring speed of the molten salt is 500 r/min; the other ways are the same.
Example 53
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (11), the stirring speed of the molten salt is 200 r/min; the other ways are the same.
Example 54
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 50.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and uniformly ground; mixing and grinding uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 5 hours;
(5) in the step (11), the stirring speed of the molten salt is 600 r/min; the other ways are the same.
Example 55
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 54 except that: (1) in the step (11), the stirring speed of the molten salt is 200 r/min; the other ways are the same.
Example 56
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride is weighed, 7.4g +/-0.1 g of potassium chloride is weighed, and the calcium chloride-potassium chloride is obtained after uniform grinding;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 5 hours;
(5) in the step (11), the stirring speed of the molten salt is 700 r/min; the other ways are the same.
Example 57
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 56, except that:
(1) in the step (11), the stirring speed of the molten salt is 500 r/min; the other ways are the same.
Example 58
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 56, except that:
(1) in the step (11), the stirring speed of the molten salt is 200 r/min; the other ways are the same.
Example 59
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, boron oxide, calcium chloride, potassium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0 +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-boron oxide and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed of the molten salt is 600 r/min; the other ways are the same.
Example 60
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 59, except that:
(1) in the step (11), the stirring speed of the molten salt is 400 r/min; the other ways are the same.
Example 61
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, boron oxide and calcium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed; the other ways are the same.
Example 62
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 61 and is different from the following:
(1) in the step (11), the stirring speed of the molten salt is 500 r/min; the other ways are the same.
Example 63
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 61 and is different from the following:
(1) in the step (11), the stirring speed of the molten salt is 200 r/min; the other ways are the same.
Example 64
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 61 and is different from the following:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and uniformly ground to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the reaction time is 5 hours;
(5) in the step (11), the stirring speed of the molten salt is 600 r/min; the other ways are the same.
Example 65
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 64, except that:
(1) in the step (11), the stirring speed of the molten salt is 400 r/min; the other ways are the same.
Example 66
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 61 and is different from the following:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride is weighed, 7.4g +/-0.1 g of potassium chloride is weighed, and the calcium chloride-potassium chloride is obtained after uniform grinding;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the reaction time is 5 hours;
the other ways are the same.
Example 67
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 66, except that:
(1) in the step (11), the stirring speed of the molten salt is 500 r/min; the other ways are the same.
Example 68
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 66, except that:
(1) in the step (11), the stirring speed of the molten salt is 200 r/min; the other ways are the same.
Example 69
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 61 and is different from the following:
(1) in the step (1), calcium silicate, boron oxide, calcium chloride, potassium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and uniformly ground to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-boron oxide and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 600r/min, and other modes are the same.
Example 70
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 69, except that:
(1) in the step (11), the stirring speed is 400r/min, and other modes are the same.
Example 71
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, calcium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (3), under the protection of inert gas, 4.3g of plus or minus 0.1g of calcium carbide and 2.8g of plus or minus 0.1g of calcium borate are weighed and mixed and ground uniformly to obtain calcium carbide-calcium borate;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
the other ways are the same.
Example 72
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (11), the stirring speed is 500 r/min; the other ways are the same.
Example 73
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (11), the stirring speed is 200 r/min; the other ways are the same.
Example 74
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 600 r/min;
the other ways are the same.
Example 75
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 74, except that:
(1) in the step (11), the stirring speed is 400 r/min; the other ways are the same.
Example 76
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 7.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 700 r/min; the other ways are the same.
Example 77
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 76 except that:
(1) in the step (11), the stirring speed is 500 r/min; the other ways are the same.
Example 78
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 76 except that:
(1) in the step (11), the stirring speed is 200 r/min; the other ways are the same.
Example 79
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (1), silicon oxide, calcium borate, calcium chloride, sodium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 40.0g +/-0.1 g of sodium chloride and 7.4g +/-0.1 g of potassium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium borate, calcium carbide-silicon oxide and calcium chloride-sodium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-sodium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 600 r/min; the other ways are the same.
Example 80
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 79, except that:
(1) in the step (11), the stirring speed is 400 r/min; the other ways are the same.
Example 81
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, calcium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (3), under the protection of inert gas, 4.3g of plus or minus 0.1g of calcium carbide and 2.8g of plus or minus 0.1g of calcium borate are weighed and mixed and ground uniformly to obtain calcium carbide-calcium borate;
(4) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed; the other ways are the same.
Example 82
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 81, except that:
(1) in the step (11), the stirring speed is 500 r/min; the other ways are the same.
Example 83
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 81, except that:
(1) in the step (11), the stirring speed is 200 r/min; the other ways are the same.
Example 84
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 81, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 600 r/min;
the other ways are the same.
Example 85
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 84 and is different from the following:
(1) in the step (11), the stirring speed is 400 r/min; the other ways are the same.
Example 86
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 81, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 7.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 700 r/min;
the other ways are the same.
Example 87
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 86 except that:
(1) in the step (11), the stirring speed is 500 r/min; the other ways are the same.
Example 88
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 86 except that:
(1) in the step (11), the stirring speed is 200 r/min; the other ways are the same.
Example 89
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 71, except that:
(1) in the step (1), calcium silicate, calcium borate, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride, 7.4g +/-0.1 g of potassium chloride and 40.0g +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-calcium borate and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(5) in the step (11), the stirring speed is 600 r/min; the other ways are the same.
Example 90
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 89, except that:
(1) in the step (11), the stirring speed is 400 r/min; the other ways are the same.
Example 91
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, borax and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (3), under the protection of inert gas, 6.5g +/-0.1 g of calcium carbide is weighed, 2.3g +/-0.1 g of borax is weighed, and the calcium carbide-borax is obtained after uniform mixing and grinding;
(4) in the step (4), 140.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(5) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(6) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 92
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 91 except that:
(1) in the step (1), calcium silicate, borax, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 90.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 93
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 91 except that:
(1) in the step (1), calcium silicate, borax, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 15.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 94
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 91 except that:
(1) in the step (1), calcium silicate, borax, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride, 15.4g +/-0.1 g of potassium chloride and 90.0g +/-0.1 g of sodium chloride are weighed, mixed and ground uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-borax and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 95
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, borax and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide and 2.7g +/-0.1 g of silicon oxide are weighed and mixed and ground uniformly to obtain calcium carbide-silicon oxide;
(3) in the step (3), under the protection of inert gas, 6.5g +/-0.1 g of calcium carbide is weighed, 2.3g +/-0.1 g of borax is weighed, and the calcium carbide-borax is obtained after uniform mixing and grinding;
(4) in the step (4), 180.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(5) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride to obtain mixed salt, and sealing;
(6) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours; the other ways are the same.
Example 96
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 95 except that:
(1) in the step (1), silicon oxide, borax, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 180.0g +/-0.1 g of calcium chloride and 120.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 97
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 95 except that:
(1) in the step (1), silicon oxide, borax, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, weighing 180.0g +/-0.1 g of calcium chloride, weighing 22.4g +/-0.1 g of potassium chloride, mixing and grinding uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-potassium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 98
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 95 except that:
(1) in the step (1), silicon oxide, borax, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, weighing 180.0g +/-0.1 g of calcium chloride, 22.4g +/-0.1 g of potassium chloride and 120.0g +/-0.1 g of sodium chloride, mixing and grinding uniformly to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-borax and calcium chloride-potassium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 99
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 98, except that:
(1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 3 hours; the other ways are the same.
Example 100
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, potassium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (3), under the protection of inert gas, 6.5g +/-0.1 g of calcium carbide and 2.6g +/-0.1 g of potassium borate are weighed and mixed and ground uniformly to obtain calcium carbide-potassium borate;
(4) in the step (4), 140.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(5) in the step (5), calcium carbide-calcium silicate, calcium carbide-potassium borate and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(6) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours; the other ways are the same.
Example 101
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, potassium borate, calcium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 90.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-potassium borate and calcium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 102
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, potassium borate, calcium chloride and potassium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 140.0g +/-0.1 g of calcium chloride and 15.4g +/-0.1 g of potassium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-potassium borate and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 103
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, potassium borate, calcium chloride, potassium chloride and sodium chloride are dried to remove adsorbed water and crystal water;
(2) in the step (4), under the protection of inert gas, 140.0g of calcium chloride, 15.4g of +/-0.1 g of potassium chloride and 90.0g of +/-0.1 g of sodium chloride are weighed, ground and uniformly mixed to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), calcium carbide-calcium silicate, calcium carbide-potassium borate and calcium chloride-potassium chloride-sodium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 104
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, potassium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (3), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide and 2.7g +/-0.1 g of silicon oxide are weighed and mixed and ground uniformly to obtain calcium carbide-silicon oxide;
(3) in the step (4), 180.0g +/-0.1 g of calcium chloride is weighed under the protection of inert gas;
(4) in the step (5), calcium carbide-silicon oxide, calcium carbide-potassium borate and calcium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(5) in the step (9), the reactor is heated to 800 ℃, calcium chloride is melted to form molten salt, and the molten salt reacts for 4 hours; the other ways are the same.
Example 105
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, potassium borate, calcium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 180.0g +/-0.1 g of calcium chloride and 120.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-potassium borate and calcium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 106
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, potassium borate, calcium chloride and potassium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, weighing 180.0g +/-0.1 g of calcium chloride, weighing 22.4g +/-0.1 g of potassium chloride, mixing and grinding uniformly to obtain calcium chloride-potassium chloride;
(3) in the step (5), calcium carbide-silicon oxide, calcium carbide-potassium borate and calcium chloride-potassium chloride are mixed uniformly to obtain mixed salt, and the mixed salt is sealed;
(4) in the step (9), the reactor is heated to 700 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 107
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), silicon oxide, potassium borate, calcium chloride, potassium chloride and sodium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (4), under the protection of inert gas, 180.0g +/-0.1 g of calcium chloride, 22.4g +/-0.1 g of potassium chloride and 120.0g +/-0.1 g of sodium chloride are weighed, ground and uniformly mixed to obtain calcium chloride-potassium chloride-sodium chloride;
(3) in the step (5), uniformly mixing calcium carbide-silicon oxide, calcium carbide-potassium borate and calcium chloride-potassium chloride-sodium chloride to obtain mixed salt, and sealing;
(4) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 4 hours;
the other ways are the same.
Example 108
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide to co-reduce silicon oxide and boron-containing oxide, which is similar to example 98, except that:
(1) in the step (9), the reactor is heated to 630 ℃, calcium chloride-potassium chloride are melted to form molten salt, and the molten salt reacts for 3 hours;
the other ways are the same.
Example 109
A method for preparing a silicon-based Si-B-C negative electrode material by using calcium carbide co-reduced silicon oxide and boron-containing oxide, which is similar to example 51, except that:
(1) in the step (1), calcium silicate, magnesium borate and calcium chloride are dried, and adsorbed water and crystal water are removed;
(2) in the step (2), under the protection of inert gas, 5.7g +/-0.1 g of calcium carbide is weighed, 5.2g +/-0.1 g of calcium silicate is weighed, and the calcium carbide-calcium silicate is obtained by mixing and grinding uniformly;
(3) in the step (3), under the protection of inert gas, 4.3g of plus or minus 0.1g of calcium carbide and 3.8g of plus or minus 0.1g of magnesium borate are weighed and mixed and ground uniformly to obtain calcium carbide-magnesium borate;
(4) in the step (4), under the protection of inert gas, 60.0g +/-0.1 g of calcium chloride and 40.0g +/-0.1 g of sodium chloride are weighed and mixed and ground uniformly to obtain calcium chloride-sodium chloride;
(5) uniformly mixing calcium carbide-calcium silicate, calcium carbide-magnesium borate and calcium chloride-sodium chloride to obtain mixed salt, and sealing;
(6) in the step (9), the reactor is heated to 750 ℃, calcium chloride-sodium chloride are melted to form molten salt, and the molten salt reacts for 5 hours;
(7) in the step (11), the stirring speed is 600 r/min; the other ways are the same.
Application example 1
The silicon-based Si-B-C negative electrode material prepared in the example 1, conductive agent acetylene black and binder PVDF are mixed according to the mass ratio: conductive agent acetylene black: binder PVDF 6: 2: 2, uniformly mixing, adding a solvent N-methyl pyrrolidone to prepare slurry, and coating the slurry on a copper foil current collector to obtain an electrode plate;
and (3) placing the electrode slice in vacuum drying, drying for 12h at 90 ℃, and after the electrode slice is completely dried, punching the electrode slice into a circular electrode slice with the diameter of 12 mm.
The obtained disk electrode sheet was used as a negative electrode, a metal lithium sheet was used as a positive electrode, Celgard2400 was used as a separator, and EC/DMC (1:1) -LiPF6(1M) was used as an electrolyte, and the battery was assembled in a glove box.
A blue CT2001A battery test system is used to perform constant current charge and discharge test in the voltage range of 0.01-1.5V. Electrochemical test results show that the coulombic efficiency of the first charge and discharge is 90 percent in the proportion of 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1437.6mAh g-1。
Application example 2
The application of the silicon-based Si-B-C anode material prepared in the example 2 is the same as the application example 1, except that:
(1) first charge-discharge coulombic efficiency of 88% at 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1517.3mAh g-1. The other ways are the same.
Application example 3
The application of the silicon-based Si-B-C anode material prepared in the embodiment 3 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 85 percent, and the first charge-discharge coulombic efficiency is 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1601.6 mAh.g-1. It is composed ofThe other modes are the same.
Application example 4
The application of the silicon-based Si-B-C anode material prepared in the example 11 is the same as the application example 1, except that:
(1) first charge-discharge coulombic efficiency of 88% at 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1451.7 mAh.g-1. The other ways are the same.
Application example 5
The application of the silicon-based Si-B-C anode material prepared in the example 14 is the same as the application example 1, except that:
(1) first charge-discharge coulombic efficiency of 86% at 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1492.6mAh g-1. The other ways are the same.
Application example 6
The application of the silicon-based Si-B-C anode material prepared in the example 16 is the same as the application example 1, except that:
(1) first charge-discharge coulombic efficiency of 84% at 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1505.6mAh g-1. The other ways are the same.
Application example 7
The application of the silicon-based Si-B-C anode material prepared in the example 19 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 82 percent, and the first charge-discharge coulombic efficiency is 0.1 A.g-1After the current density is cycled for 400 times, the reversible cycle specific capacity of the battery is 1520.6mAh g-1. The other ways are the same.
Application example 8
The application of the silicon-based Si-B-C anode material prepared in the example 41 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 85 percent, and is calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1437.6mAh g-1。
Application example 9
The application of the silicon-based Si-B-C anode material prepared in the example 42 is the same as that of the application example 1, except that:
(1) the first charge-discharge coulombic efficiency was 83%, calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1487.3mAh g-1. The other ways are the same.
Application example 10
The application of the Si-B-C based anode material prepared in the example 43 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 82%, calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1501.6mAh g-1. The other ways are the same.
Application example 11
The application of the silicon-based Si-B-C anode material prepared in example 51 is the same as that of application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 85 percent, and is calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1451.7mAh g-1. The other ways are the same.
Application example 12
The application of the Si-B-C based anode material prepared in the example 54 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 82%, calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1492.6mAh g-1. The other ways are the same.
Application example 13
The application of the silicon-based Si-B-C anode material prepared in the example 56 is the same as the application example 1, except that:
(1) the first charge-discharge coulombic efficiency is 79 percent, and is calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1535.6mAh g-1. The other ways are the same.
Application example 14
The application of the silicon-based Si-B-C anode material prepared in the example 59 is the same as that of the application example 1, except that:
(1) the first charge-discharge coulombic efficiency was 77% and calculated as 0.1 A.g-1After the current density is cycled for 500 times, the reversible cycle specific capacity of the battery is 1580.6mAh g-1. The other ways are the same.

Claims (11)

1. A preparation method of a silicon-based Si-B-C negative electrode material prepared from calcium carbide co-reduced silicon oxide and boron-containing oxide is characterized by comprising the following steps:
step 1: preparation of
(1) Respectively drying the silicon oxide, the boron-containing oxide and the molten salt raw material, and removing water; wherein the molten salt is calcium chloride-based molten salt; the silicon oxide is one or two of silicon oxide or calcium silicate;
the boron-containing oxide is boron oxide (B)2O3.) Borax (Na)2B4O7•10H2O), calcium borate, magnesium borate (Mg)2B2O5) Or potassium borate (K)2B4O7·5H2O) or a mixture of more than one of O);
(2) under the protection of inert gas, according to the stoichiometric ratio of reaction, respectively grinding the raw materials of calcium carbide-silicon oxide, calcium carbide-boron-containing oxide and molten salt until the materials are uniform, then uniformly mixing, and sealing the obtained mixed material;
(3) placing the mixed material in an embedded crucible of a reactor, and sealing;
(4) introducing inert gas into the sealed reactor, maintaining the inert atmosphere, ensuring positive pressure in the reactor, and raising the temperature of the reactor while introducing the inert gas;
step 2: synthesis of
After the temperature of the reactor is raised to the synthesis temperature, keeping the temperature for 1-5 hours to obtain a product after reaction; wherein the synthesis temperature is 530-900 ℃;
and step 3:
and placing the product after reaction in a cooling container for cooling, grinding, washing with hydrochloric acid to remove molten salt, filtering, washing with water, and drying to obtain the silicon carbide co-reduction silicon oxide and the silicon-based Si-B-C negative electrode material prepared from the boron-containing oxide.
2. The method for preparing a silicon-based Si-B-C anode material prepared by co-reducing silicon oxide with calcium carbide and boron-containing oxide according to claim 1, wherein in the step 1(1), the calcium chloride-based molten salt is one of calcium chloride, calcium chloride-sodium chloride, calcium chloride-potassium chloride and calcium chloride-sodium chloride-potassium chloride, wherein the calcium chloride-based molten salt and the calcium chloride are main salts.
3. The method for preparing silicon-based Si-B-C anode material prepared from silicon carbide co-reduced oxide and boron-containing oxide according to claim 1, wherein in the step 1(1), the drying process comprises: and (3) placing the raw materials in a high-temperature vacuum drying furnace, drying for 10-15 h at the temperature of 300-400 ℃ and under the pressure of-0.1 MPa, and removing adsorbed water and crystal water to obtain a dry molten salt raw material, a dry silicon oxide and a dry boron-containing oxide.
4. The method for preparing Si-B-C based anode material prepared by co-reducing silicon oxide with calcium carbide and boron-containing oxide according to claim 1, wherein in the step 1(2), calcium carbide (CaC) is added to the silicon oxide in a molar ratio when the silicon oxide contains silicon oxide and the boron-containing oxide contains boron oxide2): silicon oxide (SiO)2) = 2 to 2.5: 1, calcium carbide (CaC)2): boron oxide (B)2O3) = 3 to 3.5: 1, silicon oxide (SiO)2): boron oxide (B)2O3) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide and 3 times of boron oxide is more than or equal to 10: 3;
when the silicon oxide contains calcium silicate and the boron-containing oxide contains boron oxide, calcium carbide (CaC) is added in a molar ratio2): calcium silicate (CaSiO)3) = 2 to 2.5: 1, calcium carbide (CaC)2): boron oxide (B)2O3) = 3 to 3.5: 1, calcium silicate (CaSiO)3): boron oxide (B)2O3) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: calcium silicate + boron oxide is more than or equal to 10: 1;
when the silicon oxide contains silicon oxide and the boron-containing oxide contains CaB2O4In terms of molar ratio, calcium carbide (CaC)2): silicon oxide (SiO)2) = 2 to 2.5: 1, calcium carbide (CaC)2): calcium borate (CaB)2O4) = 3 to 3.5: 1, silicon oxide (SiO)2): calcium borate (CaB)2O4) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: 2 times of silicon oxide and 4 times of calcium borate are more than or equal to 10: 3;
when the silicon oxide comprises calcium silicate and the boron-containing oxide comprises CaB2O4In terms of molar ratio, calcium carbide (CaC)2): calcium silicate (CaSiO)3) = 2 to 2.5: 1, calcium carbide (CaC)2): calcium borate (CaB)2O4) = 3 to 3.5: 1, calcium silicate (CaSiO)3): calcium borate (CaB)2O4) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 4 times of boron oxide are more than or equal to 10: 3;
calcium carbide (CaC) in molar ratio when the silicon oxide contains silicon oxide and the boron-containing oxide contains borax2): silicon oxide (SiO)2) = 2 to 2.5: 1, calcium carbide (CaC)2): borax (Na)2B4O7) = 6 to 10:1, silicon oxide (SiO)2): borax (Na)2B4O7) = 4 to 20: 1, calcium chloride in calcium chloride-based molten salt: more than or equal to 10:3 of 2 times of silicon oxide and 8 times of borax;
calcium carbide (CaC) in molar ratio when the silicon oxide contains calcium silicate and the boron-containing oxide contains borax2): calcium silicate (CaSiO)3) = 2 to 2.5: 1, calcium carbide (CaC)2): borax (Na)2B4O7) = 6 to 10:1, calcium silicate (CaSiO)3): borax (Na)2B4O7) = 4 to 20: 1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 8 times of borax are more than or equal to 10: 3;
when the silicon oxide contains silicon oxide and the boron-containing oxide contains magnesium borate, calcium carbide (CaC) is added in a molar ratio2): silicon oxide (SiO)2) = 2 to 2.5: 1, calcium carbide (CaC)2): magnesium borate (Mg)2B2O5) = 3 to 3.5: 1, silicon oxide (SiO)2): magnesium borate (Mg)2B2O5) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: the ratio of 2 times of silicon oxide to 4 times of magnesium borate is more than or equal to 10: 3;
when the silicon oxide contains calcium silicate and the boron-containing oxide contains magnesium borate, calcium carbide (CaC) is added according to molar ratio2): calcium silicate (CaSiO)3) = 2 to 2.5: 1, calcium carbide (CaC)2): magnesium borate (Mg)2B2O5) = 3 to 3.5: 1, calcium silicate (CaSiO)3): magnesium borate (Mg)2B2O5) = 2 to 10:1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 4 times of magnesium borate are more than or equal to 10: 3;
when the silicon oxide contains silicon oxide and the boron-containing oxide contains potassium borate, calcium carbide (CaC) is added in a molar ratio2): silicon oxide (SiO)2) = 2 to 2.5: 1, calcium carbide (CaC)2): potassium borate (K)2B4O7) = 6 to 10:1, silicon oxide (SiO)2): potassium borate (K)2B4O7) = 4 to 20: 1, calcium chloride in calcium chloride-based molten salt: more than or equal to 10:3 of 2 times of silicon oxide and 8 times of potassium borate;
when the silicon oxide contains calcium silicate and the boron-containing oxide contains potassium borate, calcium carbide (CaC) is added in a molar ratio2): calcium silicate (CaSiO)3) = 2 to 2.5: 1, calcium carbide (CaC)2): potassium borate (K)2B4O7) = 6 to 10:1, calcium silicate (CaSiO)3): potassium borate (K)2B4O7) = 4 to 20: 1, calcium chloride in calcium chloride-based molten salt: 3 times of calcium silicate and 8 times of potassium borate are more than or equal to 10: 3.
5. The method for preparing Si-B-C based anode material prepared from silicon carbide co-reduced oxide and boron-containing oxide according to claim 1, wherein in the step 2, after the temperature of the reactor is raised to the synthesis temperature, the reactor is kept at a constant temperature, the stirring paddle is inserted into the molten salt, the stirring is maintained during the constant temperature reaction, and the rotating speed of the stirring paddle is higher than that of the reactorvIs 0<v≤700r/min。
6. A silicon-based Si-B-C anode material prepared from calcium carbide co-reduced silicon oxide and boron-containing oxide, which is characterized by being prepared by the preparation method of any one of claims 1 to 5.
7. The silicon-based Si-B-C anode material prepared from a calcium carbide co-reduced silicon oxide and a boron-containing oxide according to claim 6, wherein the silicon-based Si-B-C anode material prepared from a calcium carbide co-reduced silicon oxide and a boron-containing oxide has a particle size of 5 μm to 50 μm when statically synthesized; when the silicon-based Si-B-C anode material is stirred and synthesized, the particle size of the silicon-based Si-B-C anode material is 50nm-500 nm.
8. The use of a silicon-based Si-B-C anode material prepared from a calcium carbide co-reduced silicon oxide and a boron-containing oxide, wherein the silicon-based Si-B-C anode material prepared from the calcium carbide co-reduced silicon oxide and the boron-containing oxide according to claim 6 is used as an anode material of a lithium ion battery.
9. An anode material comprising the calcium carbide co-reduced silicon oxide according to claim 6 and a silicon-based Si-B-C anode material prepared from a boron-containing oxide.
10. An electrode sheet, characterized by comprising the negative electrode material according to claim 9, and further comprising a binder, a conductive agent, and a solvent.
11. A lithium ion battery, characterized by comprising the electrode sheet of claim 10 and a statically synthesized silicon-based Si-B-C negative electrode material, and the first charge-discharge coulombic efficiency of the silicon-based Si-B-C negative electrode material>80 percent, the first discharge reaches 2700 mAh/g; at 0.1 A.g-1Current density cycle 400 cycles with a reversible specific cycle capacity of>1400 mAh/g; stirring synthesized silicon-based Si-B-C anode material with first charge-discharge coulombic efficiency>75 percent, the first discharge reaches 2500 mAh/g; at 0.1 A.g-1Current density is cycled for 500 cycles, and the reversible cycle specific capacity is>1400mAh/g。
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103236517A (en) * 2013-04-26 2013-08-07 中国东方电气集团有限公司 Lithium ion battery silicon-based negative material and preparation method thereof
CN106129411A (en) * 2016-09-19 2016-11-16 深圳市贝特瑞新能源材料股份有限公司 A kind of hollow silicon based composites, preparation method and comprise the lithium ion battery of this composite

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5331300B2 (en) * 2006-09-15 2013-10-30 株式会社東芝 Nickel metal hydride secondary battery
CN107293700B (en) * 2016-03-31 2020-08-07 比亚迪股份有限公司 Lithium ion battery negative electrode active material, preparation method thereof, negative electrode and battery
AU2017252650A1 (en) * 2016-04-20 2018-12-06 West Virginia University Research Corporation Methods, apparatuses, and electrodes for carbide-to-carbon conversion with nanostructured carbide chemical compounds
CN110679013B (en) * 2017-09-07 2023-04-25 华盛顿州立大学 Battery with carbon coated macroscopically porous silicon anode
CN109216685A (en) * 2018-09-30 2019-01-15 东北大学 Rice hulls prepare lithium ion battery silicon-carbon negative pole material melten salt electriochemistry method

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103236517A (en) * 2013-04-26 2013-08-07 中国东方电气集团有限公司 Lithium ion battery silicon-based negative material and preparation method thereof
CN106129411A (en) * 2016-09-19 2016-11-16 深圳市贝特瑞新能源材料股份有限公司 A kind of hollow silicon based composites, preparation method and comprise the lithium ion battery of this composite

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