CN117038941B - Porous silicon-carbon anode material and preparation method and application thereof - Google Patents
Porous silicon-carbon anode material and preparation method and application thereof Download PDFInfo
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- CN117038941B CN117038941B CN202311296879.4A CN202311296879A CN117038941B CN 117038941 B CN117038941 B CN 117038941B CN 202311296879 A CN202311296879 A CN 202311296879A CN 117038941 B CN117038941 B CN 117038941B
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- porous silicon
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- HMDDXIMCDZRSNE-UHFFFAOYSA-N [C].[Si] Chemical compound [C].[Si] HMDDXIMCDZRSNE-UHFFFAOYSA-N 0.000 title claims abstract description 109
- 239000010405 anode material Substances 0.000 title claims abstract description 76
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 113
- 229910021385 hard carbon Inorganic materials 0.000 claims abstract description 109
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 103
- 239000011148 porous material Substances 0.000 claims abstract description 54
- 239000011259 mixed solution Substances 0.000 claims abstract description 49
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- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims abstract description 37
- 238000003763 carbonization Methods 0.000 claims abstract description 31
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- 230000008021 deposition Effects 0.000 claims abstract description 26
- 239000011856 silicon-based particle Substances 0.000 claims abstract description 26
- 238000005406 washing Methods 0.000 claims abstract description 26
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- 239000002253 acid Substances 0.000 claims abstract description 17
- 239000011258 core-shell material Substances 0.000 claims abstract description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 55
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- 239000002344 surface layer Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
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- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/021—Preparation
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- 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
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- H—ELECTRICITY
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- 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
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
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- 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
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- 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
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention relates to a porous silicon-carbon anode material, and a preparation method and application thereof. The porous silicon carbon anode material is of a core-shell structure, the inner core is porous hard carbon particles with silicon particles attached in the pores, the outer shell is a carbon layer, and the inner pores of the porous hard carbon particles are larger than the outer pores. The preparation method of the invention specifically comprises the following steps: the carbon source and modified lignin mixed solution are sequentially subjected to primary carbonization treatment, secondary carbonization treatment and acid washing to obtain hard carbon particles with a hierarchical porous structure, silane deposition is carried out to improve the capacity of the hard carbon particles, and finally a compact porous carbon layer is prepared on the surface of the hard carbon particles to effectively improve the compression resistance of the porous silicon carbon negative electrode material.
Description
Technical Field
The invention relates to the technical field of secondary batteries, in particular to a porous silicon-carbon negative electrode material and a preparation method and application thereof.
Background
Silicon, which is a typical alloy-type negative electrode material, has a theoretical specific capacity of up to 4200mAh/g among known negative electrodes of lithium ion batteries, and is considered as an ideal negative electrode candidate material for the next generation. At present, only the silicon-carbon composite anode material with small change rate of charge/discharge volume (less than 30 percent) and low specific capacity (less than 1000 mAh/g) is gradually applied to the scenes of electric two/three wheels, mobile phones, flat plates and the like; the silicon-carbon composite anode material with high specific capacity (more than 1000 mAh/g) has great application potential on electric tools such as electric automobiles, electric aircrafts and the like, but faces the problem of larger volume change (the volume change rate is more than 30%) in the charging/discharging process.
The silicon-carbon anode material obtained by depositing silane in a porous carbon pore structure is a lithium ion battery silicon-carbon anode material with great development prospect, and nano-scale silicon clusters are deposited and dispersed in nano carbon pores (less than 50 nm), so that the silicon-carbon anode material can provide very high reversible capacity (more than 1500 mAh/g), and a strategy for solving the problem of relatively large silicon volume change is provided: in the first lithium intercalation process, si is formed x Li y The silicon-carbon composite anode material is surrounded by a nano carbon hole structure of a carbon material, avoids mutual extrusion during expansion, well isolates nano silicon clusters, reduces the negative effect of overlarge silicon volume expansion during lithiation, improves the first coulomb efficiency and the service life of a battery, and has obvious advantages in electrochemical performance when a silicon-carbon anode material obtained by depositing silane on porous carbon, thereby being a silicon-carbon composite anode material with great application value.
Because silane deposited silicon is dispersed in the nano carbon holes, and the nano carbon holes have weaker structures, the structural strength of the silicon-carbon negative electrode material is lower, the prepared electrode plate is easy to crush during cold pressing, and a better solution is needed to be researched.
Disclosure of Invention
In order to solve the technical problems, the invention provides a porous silicon-carbon anode material and a preparation method and application thereof.
The invention is realized by the following steps:
the first object of the present invention is to provide a porous silicon-carbon anode material, which has a core-shell structure, wherein the core is porous hard carbon particles with silicon particles attached in pores, the shell is a carbon layer, and the internal pores of the porous hard carbon particles are larger than the external pores.
In one embodiment of the invention, the Dv50 of the porous silicon carbon anode material is 3.2-26 μm.
In one embodiment of the invention, the poresThe pore volume of the silicon-carbon anode material is 0.02-0.48 cm 3 /g。
In one embodiment of the invention, the tap density of the porous silicon carbon anode material is 0.6-1.8 cm 3 /g。
In one embodiment of the invention, the silicon particles are amorphous silicon.
In one embodiment of the invention, the porous silicon carbon anode material contains carbon, silicon and oxygen elements.
In one embodiment of the invention, the carbon content of the porous silicon-carbon anode material is 15-65wt%, the silicon content is 15-65wt%, the oxygen content is 0.01-8wt%, and the total amount of the carbon content and the silicon content is 80-99.99wt%.
The second object of the present invention is to provide a method for preparing the porous silicon-carbon anode material, comprising the following steps:
S1, under an alkaline condition, sequentially adding lignin and a reaction monomer into a solvent, and drying after reaction to obtain modified lignin;
s2, dispersing the modified lignin in an organic solvent to obtain a mixed solution, and adding metal salt into the mixed solution to obtain a modified lignin mixed solution;
s3, uniformly stirring and mixing the carbon source and the modified lignin mixed solution according to a certain proportion to obtain a mixed solution, and carbonizing the mixed solution once to obtain hard carbon particles;
s4, sequentially carrying out secondary carbonization treatment, acid washing treatment and drying on the hard carbon particles to obtain porous hard carbon particles;
s5, conveying the porous hard carbon particles into a reaction cavity, and introducing mixed silane gas under the conditions of a certain temperature and an inert atmosphere to perform silicon deposition to obtain porous hard carbon particles with silicon particles attached in pores;
s6, preparing a carbon layer on the surface of the porous hard carbon particles with the silicon particles attached in the pores, and obtaining the porous silicon-carbon anode material.
In one embodiment of the present invention, in step S1, the pH of the alkaline condition is 11.5-14.
In one embodiment of the present invention, in step S1, the reaction monomer is at least one selected from epichlorohydrin, propylene oxide and ethylene oxide, and the reaction monomer may be polymerized with lignin to form modified lignin.
In one embodiment of the invention, in step S1, the mass ratio of lignin to the reactive monomer is 100: 4-30.
In one embodiment of the present invention, in step S1, the solvent is deionized water.
In one embodiment of the present invention, in step S1, the reaction temperature is 30 to 65 ℃ and the reaction time is 30min to 4h.
In one embodiment of the present invention, in step S2, the organic solvent is selected from at least one of methanol, ethanol, n-propanol, isopropanol, butanol, and dimethyl dibutyl alcohol solution.
In one embodiment of the present invention, in step S2, the metal salt is selected from at least one of nickel nitrate, manganese nitrate, copper nitrate, ferric nitrate, nickel sulfate, manganese sulfate, copper sulfate, ferric sulfate, nickel chloride, manganese chloride, copper chloride, and ferric chloride, and the metal salt is subjected to a complexation reaction with lignin, so that a stable structure is formed.
In one embodiment of the present invention, in step S2, the mass ratio of the modified lignin to the metal salt is 100:0.1 to 8.
In one embodiment of the present invention, in step S2, the mass ratio of the modified lignin to the organic solvent is 1:2-30.
In one embodiment of the present invention, in step S3, the carbon source is selected from at least one of phenolic resin, epoxy resin, furfural resin, urea resin, silicone resin, polyester resin, polyamide resin, acrylic resin, vinyl resin.
In one embodiment of the present invention, in step S3, the mass ratio of the carbon source to the modified lignin mixed solution is 10:0.1 to 2.
In one embodiment of the present invention, in step S3, the primary carbonization temperature is 400-900 ℃ and the time is 30 min-3 h.
In one embodiment of the present invention, in step S4, the temperature of the secondary carbonization is 800-1500 ℃ and the time is 4-12 hours.
In one embodiment of the present invention, in step S4, the mass concentration of the acid in the pickling is 2 to 20wt%. The acid washing treatment can remove the metal elements of the metal salts complexed on the modified lignin in the hard carbon particle precursor (modified lignin mixed solution).
In one embodiment of the present invention, in step S4, the drying temperature is 75 to 120 ℃.
In one embodiment of the present invention, in step S5, the temperature is 300 to 980 ℃.
In one embodiment of the present invention, in step S5, the inert atmosphere is selected from one or more of nitrogen, helium, xenon, radon, neon, and argon.
In one embodiment of the present invention, in step S5, the mixed silane gas is a mixed gas of silane and inert gas, and the silane is one or more selected from monosilane, disilane and trisilane; the airflow ratio of the silane to the inert gas is 1-10: 0.05-10.
In one embodiment of the present invention, in step S5, the silicon deposition time is 20min to 8h.
In one embodiment of the present invention, in step S6, the method for preparing the carbon layer is vapor phase carbon deposition.
In one embodiment of the invention, the gas phase carbon is selected from one or more of methane, ethane, propane, acetylene, propyne, butyne, ethylene.
In one embodiment of the present invention, the time for vapor carbon deposition is 1 to 6 hours.
In one embodiment of the present invention, the temperature condition of the vapor carbon deposition is 300-800 ℃.
The third object of the invention is to provide a negative electrode sheet comprising the porous silicon-carbon negative electrode material or the porous silicon-carbon negative electrode material obtained by the preparation method.
A fourth object of the present invention is to provide a secondary battery including the above-described negative electrode sheet.
Compared with the prior art, the technical scheme of the invention has the following advantages:
the porous hard carbon particle core with the silicon particles attached in the pores has the hierarchical structure characteristic of a plurality of large pores in the inside and a plurality of small pores densely outwards, and the porous hard carbon particle core is combined with a carbon layer shell with compact pores, so that the tension caused by the deintercalation of lithium ions in the circulating process can be effectively buffered, and the surface structural strength and toughness of the porous silicon carbon negative electrode material are improved. The compact carbon layer shell plays a role in surface passivation at the same time, and is favorable for forming a stable SEI film on the outer surface of the porous silicon-carbon anode material, so that the problem of cracking of a material structure caused by corrosion of electrolyte byproducts is avoided. The porous hard carbon particle inner core has great amount of pores to increase the specific surface area of the material, and is favorable to depositing silicon particle, so as to raise the depositing amount of silicon and the capacity of the material.
Drawings
In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings, in which,
FIG. 1 is an SEM image of porous hard carbon particles prepared in example 1 of the invention.
Fig. 2 is an SEM image of the porous silicon carbon anode material prepared in example 4 of the present invention.
Fig. 3 is an SEM image of a negative electrode sheet prepared from the porous silicon carbon negative electrode material prepared in example 4 of the present invention.
Fig. 4 is an SEM image of a negative electrode sheet prepared from the porous silicon carbon negative electrode material prepared in comparative example 1 of the present invention.
Detailed Description
In order to solve the technical problems pointed out in the background art, the invention provides the following technical proposal to solve: carrying out short-time primary carbonization treatment on a carbon source and modified lignin mixed solution, wherein the obtained hard carbon particles are rich in anions of oxyhydrogen elements and metal salts, the hard carbon particles are slow in carbonaceous development, carbon sources in the hard carbon particles, carbon, hydrogen, oxygen elements in lignin, nitrogen, sulfur, chlorine and other elements in the metal salts need to be gasified and volatilized, and the carbon, hydrogen, oxygen, nitrogen, sulfur, chlorine and other elements in the hard carbon particles are gasified through secondary high-temperature carbonization to form the hard carbon particles with fine pores; and then acid washing is carried out to remove metal elements of metal salts in the hard carbon particle precursor (modified lignin mixed solution), so that porous hard carbon particles with internal macropores and external small pore structures are formed due to the acid washing removal of the metal elements. The internal pores are increased, and the external pores have a carbon structure less than the internal pores, so that the silane deposition is facilitated, and the purpose of improving the material capacity is achieved. The porous hard carbon particles with silicon particles attached in the pores are provided with the carbon layer with a more compact pore structure on the surfaces to form the in-situ carbon protective shell, so that the tension caused by lithium ion deintercalation in the battery cycle process can be effectively buffered, the surface structural strength and toughness of the porous silicon carbon negative electrode material are improved, the carbon layer can isolate the permeation of electrolyte and the effect of surface passivation, the stable solid electrolyte membrane (SEI film) can be formed on the outer surface, and the structural cracking caused by byproduct erosion can be avoided.
Specifically, the invention aims to provide a porous silicon-carbon anode material which has a core-shell structure, wherein the inner core is porous hard carbon particles with silicon particles attached in pores, the outer shell is a carbon layer, and the inner pores of the porous hard carbon particles are larger than the outer pores.
In an embodiment of the present invention, the Dv50 of the porous silicon carbon negative electrode material is 3.2 to 26 μm, and further, the Dv50 of the porous silicon carbon negative electrode material may be 3.2 to 10 μm, 5 to 15 μm, 12 to 21 μm, 15 to 26 μm or more.
In the embodiment of the invention, the pore volume of the porous silicon-carbon anode material is 0.02-0.48 cm 3 /g, further, the porous silicon carbon anode material can have a pore volume of 0.02-0.02 cm 3 /g、0.08cm 3 /g、0.15cm 3 /g、0.23cm 3 /g、0.29cm 3 /g、0.37cm 3 /g、0.45cm 3 The ratio/g is not equal.
In the embodiment of the invention, the tap density of the porous silicon carbon anode material is 0.6-1.8 cm 3 And/g, further, the tap density of the porous silicon carbon anode material is 0.6cm 3 /g、1.1cm 3 /g、1.4cm 3 /g、1.8cm 3 The ratio/g is not equal.
In a specific embodiment of the invention, the silicon particles are amorphous silicon.
In a specific embodiment of the invention, the porous silicon-carbon anode material contains carbon, silicon and oxygen elements.
In the specific embodiment of the invention, the carbon content of the porous silicon-carbon anode material is 15-65wt%, the silicon content is 15-65wt%, the oxygen content is 0.01-8wt%, and the total amount of the carbon content and the silicon content is 80-99.99wt%.
Another object of the present invention is to provide a method for preparing the above porous silicon carbon anode material,
the method comprises the following steps:
s1, under an alkaline condition, sequentially adding lignin and a reaction monomer into a solvent, and drying after reaction to obtain modified lignin;
s2, dispersing the modified lignin in an organic solvent to obtain a mixed solution, adding metal salt into the mixed solution, and uniformly mixing to obtain a modified lignin mixed solution;
s3, uniformly stirring and mixing the carbon source and the modified lignin mixed solution according to a certain proportion to obtain a mixed solution, and carbonizing the mixed solution once to obtain hard carbon particles;
s4, sequentially carrying out secondary carbonization treatment, acid washing treatment and drying on the hard carbon particles to obtain porous hard carbon particles;
s5, conveying the porous hard carbon particles into a reaction cavity, and introducing mixed silane gas under the conditions of a certain temperature and an inert atmosphere to perform silicon deposition to obtain porous hard carbon particles with silicon particles attached in pores;
s6, preparing a carbon layer on the surface of the porous hard carbon particles with the silicon particles attached in the pores, and obtaining the porous silicon-carbon anode material.
In a specific embodiment of the present invention, in step S1, the pH of the alkaline condition is 11.5-14.
In a specific embodiment of the present invention, in step S1, the reaction monomer is at least one selected from epichlorohydrin, propylene oxide and ethylene oxide, preferably epichlorohydrin.
In a specific embodiment of the present invention, in step S1, the solvent is deionized water.
In a specific embodiment of the present invention, in step S1, the mass ratio of the lignin to the reaction monomer is 100: 4-30.
In the embodiment of the invention, in the step S1, the reaction temperature is 30-65 ℃ and the reaction time is 30 min-4 h.
In a specific embodiment of the present invention, in step S2, the organic solvent is at least one selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, butanol, and dimethyl dibutyl alcohol solution.
In a specific embodiment of the present invention, in step S2, the metal salt is selected from at least one of nickel nitrate, manganese nitrate, copper nitrate, iron nitrate, nickel sulfate, manganese sulfate, copper sulfate, iron sulfate, nickel chloride, manganese chloride, copper chloride, and iron chloride;
in a specific embodiment of the present invention, in step S2, the mass ratio of the modified lignin to the metal salt is 100:0.1 to 8.
In a specific embodiment of the present invention, in step S3, the carbon source is at least one selected from phenolic resin, epoxy resin, furfural resin, urea resin, silicone resin, polyester resin, polyamide resin, acrylic resin, vinyl resin.
In a specific embodiment of the present invention, in step S3, the mass ratio of the carbon source to the modified lignin mixed solution is 10:0.1 to 2.
In the embodiment of the invention, in the step S3, the primary carbonization temperature is 400-900 ℃ and the time is 30 min-3 h.
In the embodiment of the invention, in the step S4, the temperature of the secondary carbonization is 800-1500 ℃ and the time is 4-12 hours.
In a specific embodiment of the present invention, in step S4, the mass concentration of the acid in the acid washing is 2 to 20wt%.
In a specific embodiment of the present invention, the acid is selected from one or more of hydrochloric acid, oxalic acid, nitric acid, formic acid, acetic acid.
In the embodiment of the present invention, in step S4, the drying temperature is 75 to 120 ℃.
In a specific embodiment of the present invention, in step S5, the temperature is 300 to 980 ℃.
In a specific embodiment of the present invention, in step S5, the inert atmosphere is one or more selected from nitrogen, helium, xenon, radon, neon, and argon.
In the specific embodiment of the present invention, in step S5, the mixed silane gas is a mixed gas of silane and inert gas, and the silane is one or more selected from monosilane, disilane and trisilane; the airflow ratio of the silane to the inert gas is 1-10: 0.05-10.
In the embodiment of the present invention, in step S5, the silicon deposition time is 20min to 8h.
In the embodiment of the present invention, in step S6, the manner of preparing the carbon layer may be a liquid phase method, a spray method, a gas phase method, and preferably a gas phase method.
In a specific embodiment of the invention, the gas phase process is polymer gas phase deposition or gas phase carbon deposition, preferably gas phase carbon deposition.
In a specific embodiment of the present invention, the gas phase carbon is selected from one or more of methane, ethane, propane, acetylene, propyne, butyne, ethylene.
In a specific embodiment of the present invention, the time for vapor carbon deposition is 1 to 6 hours.
In an embodiment of the present invention, the temperature condition of the vapor carbon deposition is 300 to 800 ℃.
The invention also provides a negative electrode plate which comprises the porous silicon-carbon negative electrode material and the porous silicon-carbon negative electrode material obtained by the preparation method.
In a specific embodiment of the present invention, the negative electrode sheet is obtained by the following preparation method: uniformly mixing a negative electrode material (the mass ratio of the porous silicon carbon negative electrode material to the graphite negative electrode material is (1-75) (99-25)), a conductive agent, a binder and deionized water to obtain a negative electrode slurry, coating the negative electrode slurry on a negative electrode current collector, drying and rolling to obtain the negative electrode sheet.
In a specific embodiment of the present invention, the conductive agent is at least one of conductive carbon black, acetylene black, graphite, graphene, carbon micro-wires, carbon nano-wires, carbon micro-tubes, and carbon nano-tubes.
In a specific embodiment of the present invention, the binder is at least one of polyvinylidene fluoride, polyimide, polyamideimide, aramid, polyacrylic acid, lithium polyacrylate, carboxymethyl cellulose, styrene-butadiene based rubber, fluororubber, polyethylene, polyvinyl alcohol, polyimide, lithium alginate, sodium alginate.
In a specific embodiment of the invention, the mass percentages of the anode material, the conductive agent and the binder are 85-99.6: 0.2-7: 0.2 to 8.0.
In a specific embodiment of the invention, the mass ratio of the porous silicon carbon anode material to the graphite anode material is (1-75): (99-25).
In a specific embodiment of the present invention, the slurry has a solid content of 40-60%, preferably 45-55%.
In a specific embodiment of the present invention, the viscosity of the slurry is 1.0 to 6pa.s, preferably 2.5 to 4pa.s.
In a specific embodiment of the present invention, the negative electrode current collector is one or more of copper foil, nickel foam/copper foil, zinc-plated copper foil, nickel-plated copper foil, carbon-coated copper foil, nickel foil, and titanium foil, preferably copper foil, nickel-plated copper foil, and carbon-coated copper foil.
In a specific embodiment of the present invention, the thickness of the negative electrode current collector is 1 to 25 μm, preferably 10 μm and 12 μm.
In a specific embodiment of the present invention, the drying temperature is 80-105 ℃.
In a specific embodiment of the present invention, the negative electrode sheet has a compacted density of 1.40 to 1.80g/cm 3 Preferably 1.55 to 1.65g/cm 3 。
In a specific embodiment of the present invention, the thickness of the negative electrode sheet is 35 to 500 μm, preferably 60 to 180 μm.
The invention also provides a secondary battery, which comprises the negative electrode plate, a positive electrode plate, a diaphragm and electrolyte.
In a specific embodiment of the present invention, the positive electrode sheet is prepared by the following method: the positive electrode active material, the conductive agent and the binder are mixed according to the mass ratio of 80-99: 0.5-10: and (3) preparing positive electrode slurry from 0.5 to 10, coating the positive electrode slurry on a positive electrode current collector, drying, rolling, cutting into pieces, and slitting to prepare the positive electrode plate of the secondary battery.
In a specific embodiment of the present invention, the positive electrode active material is selected from at least one of lithium nickel manganese oxide, lithium nickel cobalt aluminate, lithium cobalt oxide, lithium iron phosphate, lithium iron manganese fluorophosphate, and lithium nickel iron manganese oxide.
In a specific embodiment of the present invention, the positive electrode current collector is one or more of aluminum foil, foamed aluminum foil, and nickel-plated aluminum foil.
In a specific embodiment of the present invention, the separator is a polymer separator, and the polymer is at least one of polyethylene, polypropylene, polysulfonyl, polyacrylonitrile, polyvinyl alcohol, polyarylethersulfone, polyvinylidene fluoride, and polymalonic acid.
In a specific embodiment of the present invention, the secondary battery is prepared by the following method: and sequentially stacking and winding the positive plate, the isolating film and the negative plate to obtain a bare cell and an ultrasonic welding tab, putting the bare cell into a battery shell, drying at 90-120 ℃ to remove water, injecting electrolyte into the battery shell, and packaging to obtain the secondary battery.
The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to be limiting, so that those skilled in the art will better understand the invention and practice it.
Example 1
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to adjust the pH value to 12.4, adding epichlorohydrin (the mass ratio of lignin to epichlorohydrin is 100:8), reacting for 50min at 45 ℃, centrifuging, and washing the precipitate with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: and (3) stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% of 10 times of the modified lignin) and nickel sulfate at normal temperature (the mass ratio of the modified lignin to the nickel sulfate is 100:2), so as to obtain the modified lignin mixed solution.
1.3 Hard carbon particles: adding 0.3 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 500 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: the hard carbon particles are sent to a heating furnace for secondary carbonization for 6 hours at 1300 ℃, then cooled and washed with acid (the acid washing is specifically that the hard carbon particles after secondary carbonization are sent to hydrochloric acid (containing 3.4wt% of hydrogen chloride) solution with 7.5 times of mass for suction filtration and washing for 6 times), and dried at 105 ℃ to obtain porous hard carbon particles (as can be seen from figure 1, the prepared porous hard carbon particles have porous structures of internal macropores and external macropores);
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the gas flow ratio of monosilane to argon is 2:7.5) is introduced to deposit silicon for 1h (until the deposited silicon content accounts for 51wt% of the porous hard carbon particles with silicon particles attached in the pores), and the porous hard carbon particles with silicon particles attached in the pores are obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 550 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.17cm 3 Per g, dv50 of 9.4 μm, tap density of 0.9cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 48wt%, the silicon content is 50wt%, the oxygen content is 2wt%, and the total content of the carbon content and the silicon content is 98wt%.
Example 2
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to adjust the pH value to 13.2, adding epichlorohydrin (the mass ratio of lignin to epichlorohydrin is 100:8), reacting for 50min at 45 ℃, centrifuging, and washing the precipitate with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: and (3) stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% of 10 times of the modified lignin) and nickel sulfate at normal temperature (the mass ratio of the modified lignin to the nickel sulfate is 100:2.5), so as to obtain the modified lignin mixed solution.
1.3 hard carbon particles: adding 0.3 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 500 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: delivering the hard carbon particles into a heating furnace, carbonizing for 6 hours at 1300 ℃, cooling, pickling (pickling is specifically that the hard carbon particles after secondary carbonization are delivered into hydrochloric acid (containing 3.4wt% of hydrogen chloride) solution with 7.5 times of mass per se for suction filtration and washing for 6 times), and drying at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the gas flow ratio of monosilane to argon is 2:7.5) is introduced to deposit silicon for 1h (until the deposited silicon content accounts for 50wt% of the porous hard carbon particles with silicon particles attached in the pores), and the porous hard carbon particles with silicon particles attached in the pores are obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 550 ℃, introducing butyne, and depositing for 1h to obtain a porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material0.18cm 3 Per g, dv50 of 8.7 μm, tap density of 0.9cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 49wt%, the silicon content is 49wt%, the oxygen content is 2wt%, and the total amount of the carbon content and the silicon content is 98wt%.
Example 3
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to adjust the pH value to 12.9, adding epichlorohydrin (the mass ratio of lignin to epichlorohydrin is 100:8), reacting for 50min at 45 ℃, centrifuging, and washing the precipitate with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: and (3) stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% and 2-30 times of the modified lignin) and nickel sulfate at normal temperature (the mass ratio of the modified lignin to the nickel sulfate is 100:3.5), so as to obtain the modified lignin mixed solution.
1.3 hard carbon particles: adding 0.3 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 500 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: delivering the hard carbon particles into a heating furnace, carbonizing for 6 hours at 1300 ℃, cooling, and pickling (pickling is specifically carried out by delivering the hard carbon particles subjected to secondary carbonization into hydrochloric acid (containing 3.4wt% of hydrogen chloride) solution with 7.5 times of mass of the hard carbon particles, carrying out suction filtration and washing for 6 times), and drying at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the gas flow ratio of monosilane to argon is 2:7.5) is introduced to deposit silicon for 1h (until the deposited silicon content accounts for 50wt% of the porous hard carbon particles with silicon particles attached in the pores), and the porous hard carbon particles with silicon particles attached in the pores are obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 550 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.17cm 3 Per g, dv50 of 8.5 μm, tap density of 1.0cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 47wt%, the silicon content is 50wt%, the oxygen content is 3wt%, and the total amount of the carbon content and the silicon content is 97wt%.
Example 4
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to pH 12.6, adding epichlorohydrin (lignin and epichlorohydrin with mass ratio of 100:10), reacting at 50deg.C for 45min, centrifuging, collecting precipitate, and washing with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: and (3) stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% of 10 times of the modified lignin) and copper sulfate at normal temperature (the mass ratio of the modified lignin to the copper sulfate is 100:2), so as to obtain the modified lignin mixed solution.
1.3 hard carbon particles: adding 0.5 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 500 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: the hard carbon particles are sent to a heating furnace for secondary carbonization for 5 hours at 1200 ℃, then cooled and pickled (the hard carbon particles after secondary carbonization are sent to hydrochloric acid (containing 3.4 weight percent of hydrogen chloride) solution with 7.5 times of mass for suction filtration and water washing for 6 times), and dried at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the airflow ratio of monosilane to argon is 1:4) is introduced to deposit silicon for 80min (until the deposited silicon content accounts for 44wt% of the porous silicon-carbon negative electrode material), and the porous silicon-carbon negative electrode material is obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 600 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.19cm 3 Per g, dv50 of 9.3 μm, tap density of 1.1cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 54wt%, the silicon content is 44wt%, the oxygen content is 2wt%, and the total content of the carbon content and the silicon content is 98wt%.
Example 5
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to adjust the pH value to 12.6, adding epichlorohydrin (the mass ratio of lignin to epichlorohydrin is 100:10), reacting for 45min at 50 ℃, centrifuging, and washing the precipitate with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% of which the mass is 10 times of that of the modified lignin) and copper sulfate at normal temperature (the mass ratio of the modified lignin to the copper sulfate is 100:2.5), so as to obtain the modified lignin mixed solution;
1.3 hard carbon particles: adding 0.5 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 500 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: delivering the hard carbon particles into a heating furnace, carbonizing for 5 hours at 1200 ℃, cooling, pickling (pickling is specifically that the hard carbon particles after secondary carbonization are delivered into hydrochloric acid (containing 3.4wt% of hydrogen chloride) solution with 7.5 times of mass per se for suction filtration and washing for 6 times), and drying at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the gas flow ratio of monosilane to argon is 1:4) is introduced to deposit silicon for 80 minutes (until the deposited silicon content accounts for 45wt% of the porous hard carbon particles with silicon particles attached in the pores), and the porous hard carbon particles with silicon particles attached in the pores are obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 600 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.21cm 3 Per g, dv50 of 10.4 μm, tap density of 1.0cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 53wt%, the silicon content is 45wt%, the oxygen content is 2wt%, and the total amount of the carbon content and the silicon content is 98wt%.
Example 6
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to adjust the pH value to 12.8, adding epichlorohydrin (the mass ratio of lignin to epichlorohydrin is 100:10), reacting for 45min at 50 ℃, centrifuging, taking precipitate, and washing with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution which is 10 times of the modified lignin and contains 55wt percent) and copper sulfate at normal temperature (the mass ratio of the modified lignin to the copper sulfate is 100:3.5), so as to obtain the modified lignin mixed solution;
1.3 hard carbon particles: adding 0.5 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source (epoxy resin), mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 600 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: the hard carbon particles are sent into a heating furnace for secondary carbonization for 5 hours at 1200 ℃, then cooled and pickled (the pickling is that the hard carbon particles after secondary carbonization are sent into hydrochloric acid (containing 3.4 weight percent of hydrogen chloride) solution with 7.5 times of mass for suction filtration and water washing for 6 times), and dried at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the gas flow ratio of monosilane to argon is 1:4) is introduced to deposit silicon for 80 minutes (until the deposited silicon content accounts for 43wt% of the porous hard carbon particles with silicon particles attached in the pores), and the porous hard carbon particles with silicon particles attached in the pores are obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 600 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.20cm 3 Per g, dv50 of 8.9 μm, tap density of 1.1cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 55wt%, the silicon content is 43wt%, the oxygen content is 2wt%, and the total amount of the carbon content and the silicon content is 98wt%.
Example 7
The embodiment provides a preparation method of a porous silicon-carbon anode material, which comprises the following steps:
1.1 modifying lignin: dispersing lignin in 15 times of water, adding alkali (sodium hydroxide) to pH 12.6, adding epichlorohydrin (lignin and epichlorohydrin with mass ratio of 100:10), reacting at 50deg.C for 45min, centrifuging, collecting precipitate, and washing with water for 5 times to obtain modified lignin;
1.2 modified lignin mixing solution: and (3) stirring and mixing the modified lignin mixed solution (the modified lignin is dispersed in methanol solution containing 55wt% of 10 times of the modified lignin) and copper sulfate at normal temperature (the mass ratio of the modified lignin to the copper sulfate is 100:4.5), so as to obtain the modified lignin mixed solution.
1.3 hard carbon particles: adding 0.5 part by mass of modified lignin mixed solution into 10 parts by mass of carbon source A epoxy resin, mixing and stirring at 85 ℃ for 60min to obtain a carbon source mixture, feeding the carbon source mixture into a heating furnace, introducing nitrogen into the heating furnace to remove air, carbonizing for 2h at 600 ℃, cooling, ball-milling and sieving to obtain hard carbon particles with the size of 0.3-60 mu m;
1.4 porous hard carbon particles: the hard carbon particles are sent to a heating furnace for secondary carbonization for 5 hours at 1200 ℃, then cooled and pickled (the pickling is that the hard carbon particles after secondary carbonization are sent to hydrochloric acid (containing 3.4 weight percent of hydrogen chloride) solution with 7.5 times of mass for suction filtration and water washing for 6 times), and dried at 105 ℃ to obtain porous hard carbon particles;
1.5 silicon deposition: the porous hard carbon particles are sent into a fluidized bed, the temperature of the fluidized bed is controlled at 500 ℃, inert gas is introduced to remove air, mixed monosilane (the airflow ratio of monosilane to argon is 1:4) is introduced to deposit silicon for 80min (until the deposited silicon content accounts for 45wt% of the porous silicon-carbon negative electrode material), and the porous silicon-carbon negative electrode material is obtained;
1.6 surface passivation: controlling the temperature of the fluidized bed at 600 ℃, introducing butyne, and depositing for 1h to obtain the porous silicon-carbon anode material, wherein the pore volume of the obtained porous silicon-carbon anode material is 0.18cm 3 Per g, dv50 of 8.7 μm, tap density of 1.1cm 3 And/g, wherein the carbon content in the porous silicon-carbon anode material is 53wt%, the silicon content is 44wt%, the oxygen content is 3wt%, and the total amount of the carbon content and the silicon content is 97wt%.
Comparative example 1
The difference from example 1 is that: 1.3 to a carbon source (epoxy resin) was not added 0.3 parts by mass of the modified lignin mixed solution.
Comparative example 2
The difference from example 1 is that: and (3) the carbon source mixture which lacks primary carbonization, namely the carbon source mixture which lacks step 1.3, is sent to a heating furnace for primary carbonization at 500 ℃ for 2 hours, cooled, ball-milled and sieved to obtain hard carbon particles with the size of 0.3-60 mu m, 0.3 part of modified lignin mixed solution is directly added to 10 parts of carbon source A epoxy resin by mass, and the mixture is mixed and stirred at 85 ℃ for 60 minutes to obtain a carbon source mixture, sent to the heating furnace for secondary carbonization at 1300 ℃ for 6 hours, cooled and pickled (the hard carbon particles after secondary carbonization are sent to hydrochloric acid (containing 3.4wt% of hydrogen chloride) solution for suction filtration and water washing for 6 times) by 3-30 times by weight, and dried at 105 ℃ to obtain porous hard carbon particles.
Comparative example 3
The difference from example 1 is that: step 1.6 is absent and there is no surface passivation treatment.
Preparation of secondary battery:
(1) The cathode material (the cathode material prepared in the above examples and comparative examples and the graphite cathode material are obtained according to a mass ratio of 10:90), the conductive agent (conductive carbon black) and the binder (1/3 of lithium polyacrylate and 2/3 of carboxymethyl cellulose) are prepared according to a mass percentage of 95:2:3 mixing, adding deionized water, mixing to obtain a cathode slurry with solid content of 50% and viscosity of 3Pa.s, coating the cathode slurry on a cathode current collector copper foil, drying at 95deg.C, and rolling to obtain a compact density of 1.60g/cm 3 A negative electrode sheet having a thickness of 132 μm.
(2) Positive electrode active material (nickel cobalt lithium manganate), conductive agent (conductive carbon black) and binder (polyvinylidene fluoride) according to the mass ratio of 96:1.5:2.5, preparing the anode slurry, coating the anode slurry on an anode current collector aluminum foil, drying, rolling, cutting, slitting and preparing the anode plate of the secondary battery after slitting.
(3) And sequentially stacking and winding the positive plate, the polyethylene isolating film and the negative plate to obtain a bare cell and an ultrasonic welding tab, putting the bare cell into a battery shell, drying at 90-120 ℃ to remove moisture, injecting electrolyte into the battery shell, and packaging to obtain the secondary battery.
Performance test:
(1) Powder compression resistance measurement: testing the porous silicon-carbon anode materials Dv of examples 1-7 and comparative examples 1-3 at 23 ℃ by using a laser particle sizer min The powders of examples 1 to 7 and comparative examples 1 to 3 were tested for Dv by pressing with a press for 5 minutes at 56 to 58MPa min Dv before and after recording pressure min （Dv min The higher the pressure resistance of the material is, the less the negative electrode plate is easily broken in the process of rolling, the more the material structure is complete, and the better cycle performance of the secondary battery is maintained. The powder compression resistance test results of the porous silicon carbon anode materials of examples 1 to 7 and comparative examples 1 to 3 are shown in table 1.
(2) And (3) testing the cycle performance: the secondary batteries prepared from the negative electrode materials of examples and comparative examples were subjected to high-temperature formation and capacity division, and then subjected to a 0.33C constant current/4.25V constant voltage charge/1C constant current discharge cycle test at a starting voltage of 2.75V and a cut-off voltage of 4.25V at room temperature of 25 ℃, and the capacity retention rates at 100 weeks and 500 weeks were recorded. The results of the cycle performance test of the porous silicon carbon anode materials of examples 1 to 7 and comparative examples 1 to 3 are shown in Table 2.
(3) SEM test method (powder & pole piece):
and observing the surface morphology of the porous hard carbon particles prepared in the example 1, the porous silicon carbon negative electrode material prepared in the example 4, the negative electrode sheet obtained by the porous silicon carbon negative electrode material prepared in the example 4 and the negative electrode sheet obtained by the porous silicon carbon negative electrode material prepared in the comparative example 1 by using a thermal field emission scanning electron microscope under the working voltage of 10-30 KV. FIG. 1 is a porous hard carbon particle in example 1, the porous hard carbon particle having a porous structure with inner macropores and outer macropores; FIG. 2 shows a porous silicon-carbon negative electrode material of example 4, wherein the surface of the porous silicon-carbon negative electrode material is smoother after being coated with carbon, and no obvious pores are formed, so that the surface layer of the material is prevented from cracking; FIG. 3 is a negative electrode sheet prepared from the porous Si-C negative electrode material prepared in example 4, with substantially no cracking of the surface porous Si-C negative electrode material particles and graphite negative electrode material particles; fig. 4 is a view showing the case where the porous silicon carbon negative electrode material particles and the graphite negative electrode material particles on the surface of the negative electrode sheet prepared from the porous silicon carbon negative electrode material prepared in comparative example 1 are significantly broken.
TABLE 1 powder compression resistance test results for porous silicon carbon negative electrode materials of examples 1-7 and comparative examples 1-3
TABLE 2 results of cycle performance test of porous silicon carbon negative electrode materials of examples 1 to 7 and comparative examples 1 to 3
As can be seen from tables 1 and 2, compared with the comparative example, the embodiment of the invention is advantageous to improve the structural strength and toughness of the porous silicon-carbon negative electrode material by adding the modified lignin solution into the carbon source, and sequentially performing primary carbonization, secondary carbonization, acid washing treatment and carbon coating, so that the porous silicon-carbon negative electrode material Dv before and after pressing min The compression resistance of the material is improved. As can be seen from the comparison of fig. 3 (the negative electrode sheet electron microscope image of example 4) and fig. 4 (the negative electrode sheet electron microscope image of comparative example 1), the surface of the negative electrode sheet prepared from the porous silicon-carbon negative electrode material of the embodiment of the application has no cracking phenomenon, the structure of the material is kept complete, and the compression resistance of the material is good. In addition, the secondary battery prepared by the porous silicon-carbon negative electrode material has higher capacity retention rate. As can be seen from the comparison of example 1 with comparative example 1 and comparative example 2, since the modified lignin mixed solution was not added in comparative example 1 and the carbonization treatment was not performed once in comparative example 2, the negative electrode materials prepared in comparative example 1 and comparative example 2 were inferior in compression resistance, resulting in easy cracking of the electrode sheet (see fig. 4), and thus poor in capacity retention. As is clear from comparison of example 1 and comparative example 3, the lack of the carbon coating layer somewhat reduces the compression resistance and capacity retention of the negative electrode material. In a word, the porous silicon-carbon anode material prepared by the embodiment of the invention has good powder compression resistance and cycle performance.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations and modifications of the present invention will be apparent to those of ordinary skill in the art in light of the foregoing description. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (10)
1. The porous silicon-carbon anode material is characterized in that the porous silicon-carbon anode material is of a core-shell structure, the inner core is porous hard carbon particles with silicon particles attached in pores, the outer shell is a carbon layer, and the inner pores of the porous hard carbon particles are larger than the outer pores;
the preparation method of the porous silicon-carbon anode material comprises the following steps:
s1, under an alkaline condition, sequentially adding lignin and a reaction monomer into a solvent, and drying after reaction to obtain modified lignin;
s2, dispersing the modified lignin in an organic solvent to obtain a mixed solution, adding metal salt into the mixed solution, and uniformly mixing to obtain a modified lignin mixed solution;
s3, uniformly stirring and mixing the carbon source and the modified lignin mixed solution according to a certain proportion to obtain a mixed solution, and carbonizing the mixed solution once to obtain hard carbon particles;
S4, sequentially carrying out secondary carbonization treatment, acid washing treatment and drying on the hard carbon particles to obtain porous hard carbon particles;
s5, conveying the porous hard carbon particles into a reaction cavity, and introducing mixed silane gas under the conditions of a certain temperature and an inert atmosphere to perform silicon deposition to obtain porous hard carbon particles with silicon particles attached in pores;
s6, preparing a carbon layer on the surface of the porous hard carbon particles with the silicon particles attached in the pores, and obtaining the porous silicon-carbon anode material.
2. The porous silicon carbon anode material of claim 1, wherein one or more of the following conditions are satisfied:
the Dv50 of the porous silicon-carbon anode material is 3.2-26 mu m;
the pore volume of the porous silicon-carbon anode material is 0.02-0.48 cm 3 /g；
The tap density of the porous silicon carbon anode material is 0.6-1.8 cm 3 /g；
The silicon particles are amorphous silicon;
the porous silicon-carbon anode material contains carbon, silicon and oxygen;
the porous silicon-carbon anode material comprises 15-65wt% of carbon, 15-65wt% of silicon, 0.01-8wt% of oxygen and 80-99.99wt% of total carbon and silicon.
3. The porous silicon carbon anode material according to claim 1, wherein in step S1, the pH value of the alkaline condition is 11.5 to 14;
The reaction monomer is at least one selected from epichlorohydrin, propylene oxide and ethylene oxide;
the solvent is deionized water;
the mass ratio of the lignin to the reaction monomer is 100: 4-30 parts;
the reaction temperature is 30-65 ℃ and the reaction time is 30 min-4 h.
4. The porous silicon-carbon anode material according to claim 1, wherein in step S2, the organic solvent is at least one selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, butanol, and dimethyl dibutyl alcohol solution;
the metal salt is at least one selected from nickel nitrate, manganese nitrate, copper nitrate, ferric nitrate, nickel sulfate, manganese sulfate, copper sulfate, ferric sulfate, nickel chloride, manganese chloride, copper chloride and ferric chloride;
the mass ratio of the modified lignin to the metal salt is 100: 0.1-8;
the mass ratio of the modified lignin to the organic solvent is 1:2-30.
5. The porous silicon-carbon negative electrode material according to claim 1, wherein in step S3, the carbon source is at least one selected from the group consisting of phenolic resin, epoxy resin, furfural resin, urea resin, silicone resin, polyester resin, polyamide resin, acrylic resin, vinyl resin;
The mass ratio of the carbon source to the modified lignin mixed solution is 10: 0.1-2;
the primary carbonization temperature is 400-900 ℃ and the time is 30 min-3 h.
6. The porous silicon-carbon anode material according to claim 1, wherein in step S4, the secondary carbonization temperature is 800-1500 ℃ for 4-12 hours;
the mass concentration of the acid in the acid washing is 2-20wt%;
the drying temperature is 75-120 ℃.
7. The porous silicon-carbon anode material according to claim 1, wherein in step S5, the temperature is 300-980 ℃;
the inert atmosphere is one or more selected from nitrogen, helium, xenon, radon, neon and argon;
the mixed silane gas is a mixed gas of silane and inert gas, and the silane is selected from one or more of monosilane, disilane and trisilane; the airflow ratio of the silane to the inert gas is 1-10: 0.05-10;
and the silicon deposition time is 20 min-8 h.
8. The porous silicon-carbon negative electrode material according to claim 1, wherein in step S6, the manner of preparing the carbon layer is vapor phase carbon deposition;
the gas-phase carbon is selected from one or more of methane, ethane, propane, acetylene, propyne, butyne and ethylene;
The vapor carbon deposition time is 1-6 hours;
the temperature condition of the vapor carbon deposition is 300-800 ℃.
9. A negative electrode sheet comprising the porous silicon-carbon negative electrode material according to any one of claims 1 to 8.
10. A secondary battery comprising the negative electrode sheet described in claim 9.
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| CN111146430A (en) * | 2020-02-10 | 2020-05-12 | 马鞍山科达普锐能源科技有限公司 | Porous core-shell structure silicon-carbon negative electrode material for lithium ion battery and preparation method thereof |
| CN115642233A (en) * | 2022-09-30 | 2023-01-24 | 北京卫蓝新能源科技有限公司 | Graphitized porous silicon carbon negative electrode material, preparation method thereof and lithium ion battery |
| CN115642234A (en) * | 2022-09-30 | 2023-01-24 | 北京卫蓝新能源科技有限公司 | Silicon-carbon negative electrode material with pore gradient structure, preparation method thereof and lithium ion battery |
| CN116130642A (en) * | 2023-02-10 | 2023-05-16 | 江苏正力新能电池技术有限公司 | Hierarchical porous silicon-carbon negative electrode material, silicon-containing negative electrode sheet and lithium ion battery |
| CN116553547A (en) * | 2023-07-12 | 2023-08-08 | 玖贰伍碳源科技（天津）有限公司 | High-energy high-power carbon material, preparation method and sodium ion battery |
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| CN115642233A (en) * | 2022-09-30 | 2023-01-24 | 北京卫蓝新能源科技有限公司 | Graphitized porous silicon carbon negative electrode material, preparation method thereof and lithium ion battery |
| CN115642234A (en) * | 2022-09-30 | 2023-01-24 | 北京卫蓝新能源科技有限公司 | Silicon-carbon negative electrode material with pore gradient structure, preparation method thereof and lithium ion battery |
| CN116130642A (en) * | 2023-02-10 | 2023-05-16 | 江苏正力新能电池技术有限公司 | Hierarchical porous silicon-carbon negative electrode material, silicon-containing negative electrode sheet and lithium ion battery |
| CN116553547A (en) * | 2023-07-12 | 2023-08-08 | 玖贰伍碳源科技（天津）有限公司 | High-energy high-power carbon material, preparation method and sodium ion battery |
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