WO2022205904A1 - 复合负极材料及其制备方法、锂离子电池 - Google Patents

复合负极材料及其制备方法、锂离子电池 Download PDF

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WO2022205904A1
WO2022205904A1 PCT/CN2021/128547 CN2021128547W WO2022205904A1 WO 2022205904 A1 WO2022205904 A1 WO 2022205904A1 CN 2021128547 W CN2021128547 W CN 2021128547W WO 2022205904 A1 WO2022205904 A1 WO 2022205904A1
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sio
composite
negative electrode
silicon
electrode material
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French (fr)
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庞春雷
梁腾宇
任建国
贺雪琴
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BTR New Material Group Co Ltd
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BTR New Material Group Co Ltd
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Priority to EP21934540.2A priority Critical patent/EP4290620A4/en
Priority to JP2023554386A priority patent/JP2024509237A/ja
Priority to KR1020237030774A priority patent/KR20230144599A/ko
Priority to US18/549,336 priority patent/US20240182313A1/en
Publication of WO2022205904A1 publication Critical patent/WO2022205904A1/zh
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Definitions

  • the present application relates to the technical field of negative electrode materials, in particular, to a composite negative electrode material, a preparation method thereof, and a lithium ion battery.
  • the silicon-carbon composite anode material is a new type of lithium battery anode material with high capacity and long cycle. It has a capacity far higher than that of graphite and a cycle better than that of metal silicon. It is an important anode material for next-generation lithium batteries today.
  • the carbon in the silicon-carbon composite anode material can enhance the conductivity of the silicon-oxygen material system and stabilize the structure of the material, so that it has more excellent cyclic expansion performance.
  • the structure of the carbon coating layer in the existing silicon-carbon composite material is not dense enough, and there are certain pores inside the silicon-carbon composite material, which leads to the limited improvement of the conductivity of the carbon coating layer to the silicon active material, which is not conducive to improving the capacity and efficiency of the material.
  • the material particles will be pulverized during the process of deintercalating lithium from active silicon, resulting in poor stability and poor cycle performance.
  • the present application proposes a composite negative electrode material, a preparation method thereof, and a lithium ion battery, which can improve the cycle stability of the material.
  • the present application provides a composite negative electrode material
  • the composite negative electrode material includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material;
  • the physical adsorption and desorption isotherm type of the composite negative electrode material is Type II or type III
  • the physical adsorption and desorption isotherm type of the silicon oxide material is type IV or type V.
  • the physical adsorption and desorption isotherm of the silicon-oxygen material is type IV or V-type, and the silicon-oxygen material and the carbon coating layer can be more closely combined, which is beneficial to the electron conduction in the process of intercalation and delithiation.
  • the physical adsorption and desorption isotherm type of the composite negative electrode material is type II or type III, the composite negative electrode material has a dense structure, and the carbon coating layer has a certain Mechanical strength and stable structure can ensure that the integrity of particles is maintained during the process of active silicon deintercalation and lithium intercalation, inhibit particle pulverization, improve the stability of silicon-oxygen materials, and further improve the overall cycle performance of materials.
  • the composite negative electrode material has a carbon characteristic peak D, a carbon characteristic peak G and a silicon characteristic peak A, and the peak intensity ID of the carbon characteristic peak D is the same as the The ratio ID/ IG of the peak intensity IG of the carbon characteristic peak G is 0.5-2, and the ratio of the peak intensity IA of the silicon characteristic peak A to (ID+ IG ) is 0.1-10.
  • the composite negative electrode material satisfies at least one of the following conditions a to e:
  • the silicon-oxygen material includes SiO x , wherein 0 ⁇ x ⁇ 2;
  • the silicon-oxygen material also includes a composite material of SiO x
  • the composite material of SiO x includes SiO x composite SiO y , SiO x composite SiO 2 , SiO x composite Li m SiO n , SiO x composite Na m SiO n , SiO x composite K m SiO n , SiO x composite Mg m SiO n , SiO x composite Cam SiO n , SiO x composite Al m SiO n , SiO x composite amorphous carbon, SiO x composite graphite, SiO x composite graphene , at least one of SiO x composite carbon nanotubes and SiO x composite polymer materials, wherein 0 ⁇ y ⁇ 2 and x ⁇ y, m ⁇ 1, n ⁇ 1;
  • the mass percentage content of oxygen in the silicon-oxygen material is 0.1% to 50%;
  • the grain size of silicon in the silicon-oxygen material is 1 nm to 100 nm;
  • the specific surface area of the silicon-oxygen material is less than 100 m 2 /g;
  • the composite negative electrode material satisfies at least one of the following conditions a to e:
  • the particles of the composite negative electrode material are spherical or quasi-spherical, and the Wardle sphericity coefficient is greater than 0.01;
  • the average particle size of the composite negative electrode material is 1.0 ⁇ m to 50 ⁇ m;
  • the porosity of the composite negative electrode material is less than 10%
  • the specific surface area of the composite negative electrode material is 1m 2 /g ⁇ 50m 2 /g;
  • the mass percentage content of carbon in the composite negative electrode material is 0.1% to 50%.
  • the present application provides a method for preparing a composite negative electrode material, the method comprising the following steps:
  • a first aliphatic hydrocarbon gas is introduced to preheat the silicon oxide material and the first aliphatic hydrocarbon gas, wherein the physical adsorption and desorption isotherm type of the silicon oxide material is type IV or V type;
  • the second aliphatic hydrocarbon gas is introduced in an intermittent pulse mode, and the second aliphatic hydrocarbon gas is subjected to chemical vapor deposition on the preheated product to obtain the composite negative electrode material.
  • the aliphatic hydrocarbon gas can be adsorbed in the pores of the silicon-oxygen material particles whose physical adsorption and desorption isotherm type is IV or V-type by preheating, so as to fill the pores of the silicon-oxygen material, and the intermittent pulse
  • the introduction of aliphatic hydrocarbon gas will not lead to excessive deposition of local carbon sources.
  • Aliphatic hydrocarbon gas will be decomposed into zero-dimensional single carbon atom radicals or one-dimensional short carbon chains during cracking, which will be stacked more closely, which is more conducive to Forming the composite negative electrode material particles with a dense structure and spherical or quasi-spherical structure is beneficial to the integrity of the conductive network of the negative electrode material and the stability of the structure, and is beneficial to improve the cycle stability of the composite negative electrode material.
  • the preparation method satisfies at least one of the following conditions a to f:
  • the silicon-oxygen material includes SiO x , wherein 0 ⁇ x ⁇ 2;
  • the silicon-oxygen material also includes a composite material of SiO x
  • the composite material of SiO x includes SiO x composite SiO y , SiO x composite SiO 2 , SiO x composite Li m SiO n , and SiO x composite Na m SiO n , SiO x composite K m SiO n , SiO x composite Mg m SiO n , SiO x composite Cam SiO n , SiO x composite Al m SiO n , SiO x composite amorphous carbon, SiO x composite graphite, SiO x composite graphene , at least one of SiO x composite carbon nanotubes and SiO x composite polymer materials, wherein 0 ⁇ y ⁇ 2 and x ⁇ y, m ⁇ 1, n ⁇ 1;
  • the mass percentage content of oxygen in the silicon-oxygen material is 0.1% to 50%;
  • the grain size of silicon in the silicon-oxygen material is 1 nm to 100 nm;
  • the specific surface area of the silicon-oxygen material is less than 100 m 2 /g;
  • the preparation method satisfies at least one of the following conditions a to d:
  • the protective atmosphere includes at least one of nitrogen, helium, neon, argon, krypton and xenon;
  • the first aliphatic hydrocarbon gas and the second aliphatic hydrocarbon gas each independently comprise at least one of acetylene, ethylene, propyne, ethane and propylene;
  • the weight ratio A of the second aliphatic hydrocarbon gas to the silicon-oxygen material satisfies the following relationship: 1.5 ⁇ a /(1- ⁇ a ) ⁇ A ⁇ 15 ⁇ a /(1- ⁇ a ), wherein ⁇ a is the porosity of the silica material;
  • the gas flow rates of the first aliphatic hydrocarbon gas and the second aliphatic hydrocarbon gas are independently 0.1 L/min to 5 L/min.
  • the preparation method satisfies at least one of the following conditions a to e:
  • the preheating temperature is 100°C ⁇ 600°C;
  • the preheating time is 0.5h ⁇ 24h
  • reaction temperature of the chemical vapor deposition is 600°C ⁇ 1050°C;
  • the interval time of the intermittent pulse is 8s ⁇ 12s.
  • the pulse duration of the intermittent pulse is 8s ⁇ 1min.
  • the method further includes:
  • the composite negative electrode material obtained by deposition is cooled and sieved so that the average particle size of the composite negative electrode material is 1.0 ⁇ m ⁇ 50 ⁇ m.
  • the present application provides a lithium ion battery, the lithium ion battery comprising the composite negative electrode material according to the first aspect or the composite negative electrode material prepared according to the preparation method described in the second aspect.
  • the physical adsorption and desorption isotherm type of the silicon-oxygen material is IV type or V type, so that it has more bonding points with carbon and can be more closely combined with the carbon coating layer, and has It is beneficial to electron conduction and ion conduction in the process of intercalation and delithiation;
  • the physical adsorption and desorption isotherm type of the composite negative electrode material is type II or type III, indicating that the composite negative electrode material is relatively dense and stable in structure, which can ensure that the active silicon is deintercalated in the process of lithium deintercalation. Maintaining the integrity of particles, inhibiting particle pulverization, and improving the stability of silicon-oxygen materials are beneficial to long cycles and improve the cycle stability of finished batteries as a whole.
  • the preparation method is simple and easy to operate, the preparation process is safe and efficient; the manufacturing cost is effectively reduced, which is suitable for quantitative production; the obtained product is used as a battery pole piece, which is beneficial to electron conduction and ion conduction in the process of intercalation and delithiation, and is beneficial to Improve battery cycle stability.
  • Fig. 1 is the flow chart of the preparation method of the composite negative electrode material provided by the embodiment of the application;
  • Example 2 is a schematic diagram of the physical adsorption and desorption isotherm of the composite negative electrode material provided in Example 1 of the present application;
  • Example 3 is a schematic diagram of the physical adsorption and desorption isotherm of the silicon-oxygen material provided in Example 1 of the present application;
  • FIG. 4 is a schematic diagram of the physical adsorption and desorption isotherm of the composite negative electrode material provided in Comparative Example 1 of the present application.
  • the present application provides a composite negative electrode material
  • the composite negative electrode material comprises a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material;
  • the physical adsorption and desorption isotherm type of the composite negative electrode material is type II or type III,
  • the physical adsorption and desorption isotherms of silicon-oxygen materials are type IV or type V.
  • the physical adsorption and desorption isotherm type of the silicon-oxygen material is IV type or V type, which can be more closely combined with the carbon coating layer, which is conducive to the intercalation and delithiation process of electrons.
  • Conduction and ion conduction are beneficial to improve the first effect, capacity and cycle stability of the material;
  • the physical adsorption and desorption isotherm type of the composite negative electrode material is type II or type III, indicating that the composite negative electrode material has a dense structure, and the carbon coating layer has With a certain mechanical strength and stable structure, it can ensure the integrity of the particles during the process of de-intercalating lithium from active silicon, inhibit particle pulverization, improve the stability of the silicon-oxygen material, and further improve the cycle performance of the material as a whole.
  • the silicon-oxygen material includes SiO x , where 0 ⁇ x ⁇ 2; SiO x may specifically be SiO 0.5 , SiO 0.8 , SiO 0.9 , SiO, SiO 1.1 , SiO 1.2 or SiO 1.5 and the like.
  • the silicon oxide material is SiO.
  • the composition of SiO x is relatively complex, which can be understood as being formed by the uniform dispersion of nano-silicon in SiO 2 .
  • the silicon-oxygen material further includes a composite material of SiO x
  • the composite material of SiO x includes SiO x composite SiO y , SiO x composite SiO 2 , SiO x composite Li m SiO n , SiO x composite Na m SiO n , SiO x complex K m SiO n , SiO x complex Mg m SiO n , SiO x complex Cam SiO n , SiO x complex Al m SiO n , SiO x complex amorphous carbon, SiO x complex graphite, SiO x complex At least one of graphene, SiO x composite carbon nanotube and SiO x composite polymer material, wherein 0 ⁇ y ⁇ 2 and x ⁇ y, m ⁇ 1, n ⁇ 1.
  • the grain size of silicon in the silicon oxide material is 1 nm to 100 nm; specifically, it may be 1 nm, 10 nm, 20 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm or 100 nm, etc., However, it is not limited to the recited numerical values, and other unrecited numerical values within the numerical range are equally applicable. It is understandable that the silicon grain size of the silicon-oxygen material is controlled within the above-mentioned range, which is beneficial to improve the structural stability, thermal stability and long-term cycle stability of the negative electrode material. It should be noted that the grain size of silicon in the silicon-oxygen material is the half-width of the 28.6°Si(111) peak measured by XRD pattern, and calculated by Scherrer's formula.
  • the mass percentage content of oxygen in the silicon-oxygen material is 0.1% to 50%, specifically 0.1%, 1%, 10%, 20%, 25%, 30%, 35%, 40% or 50%, etc., but are not limited to the recited values, and other unrecited values within this range of values are equally applicable.
  • the oxygen content in the silicon-oxygen material is too high, the material capacity will decrease, and the first Coulomb efficiency will decrease; when the oxygen content in the silicon-oxygen material is too low, that is, the silicon content will increase, which will easily cause the material to expand easily during the cycle. lead to serious powdering of the material.
  • the specific surface area of the silicon - oxygen material is less than 100 m 2 / g ; 50m 2 /g or 90m 2 /g, etc., but not limited to the recited values, and other unrecited values within the range of values are also applicable.
  • the specific surface area of the composite negative electrode material is within the above range, which ensures the processing performance of the material, is beneficial to improve the primary efficiency of the lithium battery made of the negative electrode material, and is beneficial to improve the cycle performance of the negative electrode material.
  • the porosity ⁇ a ⁇ 10% of the silicon-oxygen material can be specifically 1%, 2%, 3%, 5%, 6%, 8% or 9%, etc., but not limited to the listed ones value, other non-recited values within this value range also apply.
  • the porosity of the silicon-oxygen material is too high, it is not conducive to forming a composite material with a dense structure, and is not conducive to improving the cycle stability of the material.
  • the porosity of the silicon-oxygen material is 1% ⁇ a ⁇ 10%.
  • the composite negative electrode material is spherical or quasi-spherical, and its Wardle sphericity coefficient is greater than 0.01, specifically 0.02, 0.04, 0.08, 0.1, 0.15, 0.2, 0.25, 0.3, 0.5, 0.6, 0.8, 0.9 , 0.95 or 0.99, but are not limited to the recited values, and other unrecited values within this range of values are equally applicable.
  • the Wardle shape coefficient of the composite negative electrode material is 0.1-0.3.
  • the specific surface area of the composite negative electrode material ranges from 1 m 2 /g to 50 m 2 /g; specifically, it can be 1 m 2 /g, 10 m 2 /g, 15 m 2 /g, 20 m 2 /g, 25 m 2 /g , 30m 2 /g, 35m 2 /g, 40m 2 /g, 45m 2 /g or 50m 2 /g, etc., but are not limited to the listed values, and other unlisted values within the numerical range are also applicable.
  • the specific surface area of the composite negative electrode material is within the above range, which ensures the processing performance of the material, is beneficial to improve the primary efficiency of the lithium battery made of the negative electrode material, and is beneficial to improve the cycle performance of the negative electrode material.
  • the average particle size of the composite negative electrode material is 1.0 ⁇ m to 50 ⁇ m, specifically 1.0 ⁇ m, 2.0 ⁇ m, 3.0 ⁇ m, 4.0 ⁇ m, 5.0 ⁇ m, 10 ⁇ m, 15 ⁇ m, 20 ⁇ m, 30 ⁇ m or 50 ⁇ m, etc.
  • the average particle size of the composite negative electrode material is controlled within the above range, which is beneficial to the improvement of the cycle performance of the negative electrode material.
  • the average particle size of the composite negative electrode material is 1.0 ⁇ m ⁇ 10 ⁇ m. If the average particle size of the composite anode material is too large, the cycle performance of the material decreases, the rate performance decreases, and the first efficiency of the battery decreases.
  • the porosity of the composite negative electrode material is less than 10%; specifically, it may be 0.5%, 1.0%, 2.0%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 9.9% %, etc., but are not limited to the recited values, and other unrecited values within the numerical range are also applicable. Controlling the porosity of the composite negative electrode material within the above range will enable the material to have good rate performance.
  • the mass percentage content of carbon in the composite negative electrode material is 0.1% to 50%; specifically, it may be 0.1%, 3.0%, 5.0%, 10.0%, 15.5%, 20%, 30% or 50%, etc. etc., but are not limited to the recited numerical values, and other unrecited numerical values within the numerical range are equally applicable. If the carbon content is too high, the lithium ion transmission efficiency is reduced, which is not conducive to the high-rate charge and discharge of the material, and the overall performance of the negative electrode material is reduced. Lead to long cycle performance price difference.
  • the mass percentage content of carbon in the composite negative electrode material is 1% to 10%.
  • the composite negative electrode material in the Raman spectrum, has a carbon characteristic peak D, a carbon characteristic peak G and a silicon characteristic peak A, the peak intensity ID of the carbon characteristic peak D and the peak intensity I G of the carbon characteristic peak G
  • the ratio ID/ IG is 0.5 to 2, specifically 0.5, 0.8, 1.0, 1.2, 1.5, 1.8 or 2.0, etc.
  • the ratio of ID/IG is too large, the efficiency of the composite negative electrode material decreases for the first time;
  • the ratio of ID/IG is too small, the rate performance of the composite anode material decreases.
  • the ID/ IG value is in this range, it indicates that the carbon layer is formed by the cracking of chain carbon chains, and it is difficult to generate graphite sheets.
  • the ratio of the peak intensity IA of the silicon characteristic peak A to (ID + IG ) is 0.1 to 10, specifically 0.1, 0.2, 0.3, 0.5, 0.6, 0.8 or 1.0, etc.
  • the ratio of IA /(ID + IG ) is too large, the cycle performance of the composite negative electrode material decreases; when the ratio of IA / (ID + IG ) is too small, the specific discharge capacity of the composite negative electrode material decreases, which is not conducive to improving the The energy density of the battery.
  • I A /(ID + IG ) values the carbon coating is tight and silicon is not easily exposed outside the carbon layer.
  • the present application provides a method for preparing a composite negative electrode material, comprising the following steps:
  • Step S100 in a protective atmosphere, the first aliphatic hydrocarbon gas is introduced to preheat the silicon oxide material and the first aliphatic hydrocarbon gas, wherein the physical adsorption and desorption isotherm type of the silicon oxide material is IV type or V type;
  • step S200 the second aliphatic hydrocarbon gas is introduced in an intermittent pulse manner, so that the second aliphatic hydrocarbon gas is subjected to chemical vapor deposition on the preheated product to obtain a composite negative electrode material.
  • the first aliphatic hydrocarbon gas can be adsorbed in the pores of the silicon-oxygen material particles whose physical adsorption and desorption isotherm type is IV or V-type by preheating, so as to fill the pores of the silicon-oxygen material.
  • the physical adsorption and desorption isotherm type of oxygen material is type IV or type V, which is more conducive to the deposition of the first aliphatic hydrocarbon gas in the pores.
  • the second aliphatic hydrocarbon gas is decomposed into zero-dimensional single carbon atom radicals or one-dimensional shorter carbon chains during cracking, which will be more closely stacked with each other, which is more conducive to the formation of dense structure and spherical or spherical-like composite negative electrode material particles , which is beneficial to the integrity of the conductive network of the negative electrode material and the stability of the structure, and is beneficial to improve the cycle stability of the composite negative electrode material.
  • Step S100 in a protective atmosphere, a first aliphatic hydrocarbon gas is introduced to preheat the silicon oxide material and the first aliphatic hydrocarbon gas.
  • the silicon oxide material includes SiO x , wherein 0 ⁇ x ⁇ 2; more specifically, SiO x may be SiO 0.5 , SiO 0.8 , SiO 0.9 , SiO, SiO 1.1 , SiO 1.2 or SiO 1.5 etc.
  • the silicon oxide material is SiO.
  • the composition of SiO x is relatively complex, which can be understood as being formed by the uniform dispersion of nano-silicon in SiO 2 .
  • the silicon oxide material further includes a composite material of SiO x
  • the composite material of SiO x includes SiO x composite SiO y , SiO x composite SiO 2 , SiO x composite Li m SiO n , SiO x composite Nam SiO n , SiO x complex K m SiO n , SiO x complex Mg m SiO n , SiO x complex Cam SiO n , SiO x complex Al m SiO n , SiO x complex amorphous carbon, SiO x complex graphite, SiO At least one of x composite graphene, SiO x composite carbon nanotube and SiO x composite polymer material, wherein 0 ⁇ y ⁇ 2 and x ⁇ y, m ⁇ 1, n ⁇ 1.
  • the grain size of silicon in the silicon oxide material is 1 nm to 100 nm; specifically, it may be 1 nm, 10 nm, 20 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm or 100 nm, etc., However, it is not limited to the recited numerical values, and other unrecited numerical values within the numerical range are equally applicable. It is understandable that the silicon grain size of the silicon-oxygen material is controlled within the above-mentioned range, which is beneficial to improve the structural stability, thermal stability and long-term cycle stability of the negative electrode material. It should be noted that the grain size of silicon in the silicon-oxygen material is the half-width of the 28.6°Si(111) peak measured by XRD pattern, and calculated by Scherrer's formula.
  • the mass percentage content of oxygen in the silicon-oxygen material is 0.1% to 50%, specifically 0.1%, 1%, 10%, 20%, 25%, 30%, 35%, 40% or 50%, etc., but are not limited to the recited values, and other unrecited values within this range of values are equally applicable.
  • the oxygen content in the silicon-oxygen material is too high, the material capacity will decrease, and the first Coulomb efficiency will decrease; when the oxygen content in the silicon-oxygen material is too low, that is, the silicon content will increase, which will easily cause the material to expand during the cycle. , resulting in serious pulverization of the material.
  • the specific surface area of the silicon - oxygen material is less than 100 m 2 / g ; 50m 2 /g or 100m 2 /g, etc., but not limited to the recited values, and other unrecited values within the range of values are also applicable.
  • the specific surface area of the composite negative electrode material is within the above range, which ensures the processing performance of the material, is beneficial to improve the primary efficiency of the lithium battery made of the negative electrode material, and is beneficial to improve the cycle performance of the negative electrode material.
  • the porosity ⁇ a ⁇ 10% of the silicon-oxygen material can be specifically 1%, 2%, 3%, 5%, 6%, 8% or 10%, etc., but not limited to the listed ones value, other non-recited values within this value range also apply.
  • the porosity of the silicon-oxygen material is too high, it is not conducive to forming a composite material with a dense structure, and it is not conducive to improving the cyclic stability of the material.
  • the protective atmosphere includes at least one of nitrogen, helium, neon, argon, krypton, and xenon. Heat treatment in a protective atmosphere can improve the safety of the reaction.
  • the first aliphatic hydrocarbon gas includes at least one of acetylene, ethylene, propyne, ethane, and propylene.
  • the gas flow rate of the first aliphatic hydrocarbon gas ranges from 0.1L/min to 5L/min, specifically 0.1L/min, 0.5L/min, 1L/min, 1.5L/min, 2L/min, 2.5L/min, 3L/min, 3.5L/min or 5L/min, etc., but not limited to the listed values, and other unlisted values within the numerical range are also applicable.
  • the preheating temperature is 100°C to 600°C, specifically 100°C, 200°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C or 600°C, etc., but not only Limitation to the recited values applies equally to other non-recited values within the range of values.
  • the preheating time is 0.5h to 24h; specifically, it can be 0.5h, 1.0h, 1.5h, 3h, 5h, 6h, 8h, 12h, 15h, 18h or 24h, etc.
  • the first The aliphatic hydrocarbon gas can be adsorbed into the pores inside and on the surface of the silica material, which is beneficial to the formation of a dense carbon coating.
  • the preheating temperature is 400° C. ⁇ 600° C.
  • the preheating time is 1 h ⁇ 5 h.
  • step S200 the second aliphatic hydrocarbon gas is introduced in an intermittent pulse manner, so that the second aliphatic hydrocarbon gas is subjected to chemical vapor deposition on the preheated product to obtain a composite negative electrode material.
  • the stacking of each other will be more closely, which is more conducive to the formation of a dense structure of composite negative materials, which is conducive to the integrity of the conductive network of the material. And the stability of the structure is beneficial to improve the cycle stability of the composite anode material.
  • a conventional solid-phase carbon source such as an organic substance containing aromatic rings or higher aliphatic hydrocarbons, its boiling point is generally higher than the decomposition point, and it decomposes into two-dimensional carbon rings or long carbon chains during cracking.
  • the physical adsorption and desorption isotherms obtained by pore size analysis have hysteresis loops.
  • aromatic hydrocarbon gases such as benzene vapor
  • the physical adsorption and desorption isotherms obtained by pore size analysis have hysteresis. ring, which is not conducive to maintaining the cycle stability of the negative electrode material.
  • the weight ratio A of the second aliphatic hydrocarbon gas to the silicon oxide material satisfies the following relationship: 1.5 ⁇ a /(1- ⁇ a ) ⁇ A ⁇ 15 ⁇ a /(1- ⁇ a ), wherein ⁇ a is the porosity of the silica material.
  • the second aliphatic hydrocarbon gas includes at least one of acetylene, ethylene, propyne, ethane, and propylene.
  • the gas flow rate of the second aliphatic hydrocarbon gas ranges from 0.1L/min to 5L/min, specifically 0.1L/min, 0.5L/min, 1L/min, 1.5L/min, 2L/min, 2.5L/min, 3L/min, 3.5L/min or 5L/min, etc., but not limited to the listed values, and other unlisted values within the numerical range are also applicable.
  • the reaction temperature of chemical vapor deposition is 600°C to 1050°C, specifically 600°C, 700°C, 800°C, 850°C, 900°C, 950°C, 1000°C or 1050°C, etc., but not only Limitation to the recited values applies equally to other non-recited values within the range of values. Understandably, through chemical vapor deposition, the second aliphatic hydrocarbon gas is decomposed into zero-dimensional single carbon atom radicals or one-dimensional shorter carbon chains during cracking, which will be stacked more closely with each other, which is more conducive to forming a composite negative electrode with a dense structure. It is beneficial to the integrity of the conductive network of the material and the stability of the structure, and it is beneficial to improve the cycle stability of the composite negative electrode material. Preferably, the reaction temperature of chemical vapor deposition is 800°C ⁇ 1000°C.
  • the aliphatic hydrocarbon gas is continuously passed through in an intermittent pulse manner, and the interval between the intermittent pulses is 8s ⁇ 12s.
  • the pulse duration of the intermittent pulse is 8s ⁇ 1min.
  • the pulse duration may be the aliphatic hydrocarbon gas fed for 10s every 10s.
  • the carbon source gas (the second aliphatic hydrocarbon gas) is introduced in intermittent pulse mode, which is not easy to cause excessive local deposition of the carbon source on the surface of the silicon-oxygen material, which is beneficial to improve the uniformity of the carbon coating layer on the surface of the silicon-oxygen material. It is beneficial to form a uniform and dense carbon coating layer.
  • the method of continuously feeding the second aliphatic hydrocarbon gas is adopted, it is unfavorable to generate the physical adsorption and desorption isotherm type of the composite negative electrode material to be type II or type III structure, which is not conducive to improving the cycle stability of the negative electrode material.
  • the method further includes:
  • the composite negative electrode material obtained by deposition is cooled and sieved so that the average particle size of the composite negative electrode material is 1.0 ⁇ m to 50 ⁇ m, specifically 1 ⁇ m, 5 ⁇ m, 10 ⁇ m, 15 ⁇ m, 20 ⁇ m, 30 ⁇ m, 40 ⁇ m or 50 ⁇ m.
  • the average particle size of the composite negative electrode material is controlled within the above range, which is beneficial to the improvement of the cycle performance of the negative electrode material.
  • the average particle size of the composite negative electrode material is 1 ⁇ m ⁇ 10 ⁇ m.
  • screening includes at least one of crushing, ball milling, screening, or classification.
  • the present application provides a lithium ion battery, the lithium ion battery comprising the composite negative electrode material of the first aspect or the composite negative electrode material prepared by the preparation method of the second aspect.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S1 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • the physical adsorption and desorption isotherm of the composite negative electrode material is shown in Figure 2. It can be seen that the physical adsorption and desorption isotherm type is type II; after the carbon element in the composite negative electrode material is removed by burning, the measured The physical adsorption and desorption isotherm is shown in Figure 3, and the physical adsorption and desorption isotherm type is IV.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S2 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S3 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S4 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S5 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S6 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S7 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S8 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S9 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material S10 prepared in this example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • a preparation method of a composite negative electrode material comprising the following steps:
  • a preparation method of a composite negative electrode material comprising the following steps:
  • the composite negative electrode material D2 prepared in this comparative example includes a silicon-oxygen material and a carbon coating layer on the surface of the silicon-oxygen material.
  • the physical adsorption and desorption isotherm type of composite anode material D2 is type IV.
  • the average particle size of the composite negative electrode material obtained in the above-described embodiment and the comparative example is measured using a laser particle size analyzer, as shown in Table 1;
  • the specific surface area of the composite negative electrode material made by the above-described embodiment and the comparative example is respectively as shown in Table 1 using the BET method nitrogen adsorption specific surface area meter to measure the material;
  • the composite negative electrode material that the above-mentioned embodiment and comparative example are made use the specific surface area and average particle diameter that record respectively to obtain the wadell (Wadell) sphericity of material particle, concrete numerical value is as shown in table 1;
  • the composite negative electrode material that above-mentioned embodiment and comparative example make use Raman spectrometer to record Raman spectrum respectively, in Raman spectrum, described composite negative electrode material has carbon characteristic peak D, carbon characteristic peak G and silicon characteristic Peak A, the ratio ID / IG of the peak intensity ID of the carbon characteristic peak D to the peak intensity I G of the carbon characteristic peak G , and the peak intensity I A and (ID of the silicon characteristic peak A + IG ) ratio, as shown in Table 1;
  • the composite negative electrode material obtained by the above-described embodiment and the comparative example is analyzed using a trace carbon analyzer, and the mass percentage content of the carbon that obtains the composite negative electrode material is as shown in Table 1;
  • the composite negative electrode materials made by the above-mentioned examples and comparative examples were placed under a 300-degree air-atmosphere electric furnace and processed until constant weight, and when the carbon content was less than 0.1% using a trace carbon analyzer, the obtained decarbonization Treated silica material.
  • the specific surface area of the silicon-oxygen material after the carbon removal treatment was measured by the BET method nitrogen adsorption specific surface area meter, as shown in Table 1;
  • the above-mentioned composite negative electrode material was treated with the mixed acid composed of excess hydrofluoric acid and concentrated nitric acid, until the mixed acid was added and placed for 30min and no reddish-brown gas was released, then the material was filtered and dried.
  • the resulting treated material is the carbon coating.
  • Use a nitrogen adsorption pore size analyzer to test the pore size distribution of the carbon coating in the pore size range of 1.7 nm to 300 nm, and obtain the physical adsorption and desorption isotherms and porosity.
  • the physical adsorption and desorption isotherms are in the p/p0 range of 0 to 1. Whether there is a hysteresis loop and its physical adsorption and desorption isotherm type, the results are shown in Table 1;
  • the carbon coating layer prepared above was subjected to a charge-discharge test to obtain the charge-discharge capacity of the carbon coating layer. The results are shown in Table 1.
  • the above-mentioned carbon cladding layer is used to measure the Raman spectrum using a Raman spectrometer, respectively.
  • the carbon cladding layer has a carbon characteristic peak D, a carbon characteristic peak G, and the carbon characteristic peak
  • the ratio ID/IG of the peak intensity ID of D to the peak intensity IG of the carbon characteristic peak G is shown in Table 1.
  • the negative electrode materials, conductive carbon black and PAA glue prepared in Examples 1-10 and Comparative Examples 1-2 were prepared into negative electrode slurry in a mass ratio of 75:15:10, coated on copper foil, and dried. Then the negative pole piece is made.
  • the lithium metal sheet was used as the counter electrode to assemble a button battery in an argon-filled glove box. Under the current density of 0.1C, the charge-discharge range is 0.01-1.5V for the charge-discharge test. The test obtained the first reversible specific capacity, first efficiency and capacity retention rate after 50 cycles of the battery.
  • the first coulomb efficiency test was performed on the above 12 sets of batteries on the Blue Power CT2001A battery test system.
  • the charge and discharge current was 0.05C, and the first coulomb efficiency was measured.
  • the results are shown in Table 2.
  • the physical adsorption and desorption isotherms of the composite negative electrode material of Example 1 are type II
  • the physical adsorption and desorption isotherms of the silicon-oxygen material of Example 1 are type IV.
  • the physical adsorption and desorption isotherms of the composite negative electrode materials prepared in Examples 2 to 8 are type II or type III, indicating that the composite negative electrode materials are relatively compact and stable in structure, and can ensure that the active silicon is deintercalated during the lithium extraction process. The integrity of the particles is inhibited, and the cycle stability of the battery made from it is effectively improved.
  • the gas will lead to excessive deposition of local carbon sources of the silicon-oxygen material, the mass proportion of the negative electrode active material (silicon-oxygen material) is reduced, and the first discharge specific capacity and the first coulombic efficiency of the negative electrode material are significantly reduced.
  • the conductivity of the negative electrode material decreases, and the first discharge specific capacity, the first coulomb efficiency, and the cycle retention rate are all lower than those in Example 1.
  • Comparative Example 1 The main difference between Comparative Example 1 and Example 1 is that the second aliphatic hydrocarbon gas introduced during chemical vapor deposition is benzene vapor, and the benzene vapor (C 6 H 6 ) becomes a two-dimensional carbocyclic ring after being cracked.
  • the coated composite anode material Compared with the one-dimensional short carbon chains or zero-dimensional carbon atoms formed by the cracking of ethylene, the coated composite anode material has a hysteresis loop in the physical adsorption and desorption isotherms of pore size analysis, as shown in Figure 4.
  • the wire is type IV, and the cycle capacity retention of Comparative Example 1 is lower than that of Example 1.
  • Comparative Example 2 The main difference between Comparative Example 2 and Example 1 is that during chemical vapor deposition, the second aliphatic hydrocarbon gas is continuously fed, and the intermittent pulse form is not used to pass in, resulting in excessive local deposition of the carbon source on the surface of the silicon oxide material, which is not conducive to Improve the uniformity of the carbon coating layer on the surface of the silicon-oxygen material, the physical adsorption and desorption isotherm type of the prepared composite negative electrode material is type IV, and the cycle capacity retention rate of Comparative Example 2 is lower than that of Example 1. , which is not conducive to improving the cycle stability of the negative electrode material.
  • the present application provides a method for preparing a composite negative electrode material, which is simple and easy to operate, and has a safe and efficient preparation process; the manufacturing cost is effectively reduced, which is suitable for quantitative production; the obtained product is used as a battery pole piece, which is beneficial to insertion and removal
  • the electron conduction and ion conduction in the lithium process are beneficial to improve the battery cycle stability.

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Abstract

本申请涉及负极材料领域，提供一种复合负极材料及其制备方法、锂离子电池，所述复合负极材料包括硅氧材料和位于所述硅氧材料表面的碳包覆层；所述复合负极材料的物理吸脱附等温线类型为II型或III型，所述硅氧材料的物理吸脱附等温线类型为IV型或V型。本申请的复合负极材料及其制备方法、锂离子电池，能够有效提高锂电池的倍率性能及循环稳定性。

Description

复合负极材料及其制备方法、锂离子电池
本申请要求于2021年03月29日提交中国专利局，申请号为2021103353838、申请名称为“复合负极材料及其制备方法、锂离子电池”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及负极材料技术领域，具体地讲，涉及复合负极材料及其制备方法、锂离子电池。
背景技术
硅碳复合负极材料为高容量长循环新型锂电池负极材料，具有远高于石墨的容量及优于金属硅的循环，为当今重要的下一代锂电池负极材料。硅碳复合负极材料中的碳可以为硅氧材料体系增强导电性及稳定材料的结构，使其具有更优异的循环膨胀性能。但是现有的硅碳复合材料中碳包覆层结构不够密实，硅碳复合材料内部存在一定的孔隙，导致碳包覆层对硅活性材料的电导率提升有限，不利于提高材料的容量和首效，而且活性硅脱嵌锂过程中材料颗粒会发生粉化，稳定性差，进而导致循环性能差。
申请内容
鉴于此，本申请提出复合负极材料及其制备方法、锂离子电池，能够提高材料循环稳定性。
第一方面，本申请提供一种复合负极材料，所述复合负极材料包括硅氧材料和位于所述硅氧材料表面的碳包覆层；所述复合负极材料的物理吸脱附等温线类型为II型或III型，所述硅氧材料的物理吸脱附等温线类型为IV型或V型。
本申请提供的复合负极材料中，硅氧材料的物理吸脱附等温线类型为IV型或V型，硅氧材料与碳包覆层能更紧密地结合，有利于嵌脱锂过程中电子传导和离子传导，有利于提高材料的首效、容量和循环稳定性；复合负极材料的物理吸脱附等温线类型为II型或III型，复合负极材料具有密实结构，碳包覆层具有一定的机械强度，结构稳定，能够保证在活性硅脱嵌锂过程中保持颗粒的完整性，抑制颗粒粉化，提升硅氧材料稳定性，进一步从整体上改善材料的循环性能。
本申请中，物理吸脱附等温线类型的分类依据是国际纯粹与应用化学联合会(IUPAC)提出的物理吸脱附等温线分类方法。
在一种可行的实施方式中，在拉曼光谱中，所述复合负极材料具有碳特征峰D、碳特征峰G及硅特征峰A，所述碳特征峰D的峰强度I D与所述碳特征峰G的峰强度I G的比值I D/I G为0.5～2，且所述硅特征峰A的峰强度I A与(I D+I G)的比值为0.1～10。
在一种可行的实施方式中，所述复合负极材料满足以下条件a～e的至少一者：
a.所述硅氧材料包括SiO x，其中，0<x<2；
b.所述硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、 SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至少一种，其中，0<y<2且x≠y，m≥1，n≥1；
c.所述硅氧材料中氧的质量百分含量为0.1％～50％；
d.所述硅氧材料中硅晶粒尺寸为1nm～100nm；
e.所述硅氧材料的比表面积小于100m 2/g；
f.所述硅氧材料的孔隙率φ a<10％。
在一种可行的实施方式中，所述复合负极材料满足以下条件a～e的至少一者：
a.所述复合负极材料颗粒呈球形或类球形，其沃德尔球形度系数大于0.01；
b.所述复合负极材料的平均粒径为1.0μm～50μm；
c.所述复合负极材料的孔隙率小于10％；
d.所述复合负极材料的比表面积为1m 2/g～50m 2/g；
e.所述复合负极材料中碳的质量百分含量为0.1％～50％。
第二方面，本申请提供一种复合负极材料的制备方法，所述方法包括以下步骤：
在保护性气氛下，通入第一脂肪烃气体，将硅氧材料和所述第一脂肪烃气体进行预热，其中，所述硅氧材料的物理吸脱附等温线类型为IV型或V型；
以间歇脉冲方式通入第二脂肪烃气体，使所述第二脂肪烃气体在所述预热后的产物上进行化学气相沉积，得到所述复合负极材料。
在上述方案中，先通过预热，使得脂肪烃气体能够吸附在物理吸脱附等温线类型为IV型或V型的硅氧材料颗粒的孔隙内，从而填充硅氧材料的孔隙，间歇式脉冲通入脂肪烃气体，不会导致局部碳源过多沉积，脂肪烃气体在裂解时分解成零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密，更有利于形成密实结构且球形或类球形的复合负极材料颗粒，有利于负极材料导电网络的完整及结构的稳定性，有利于提高复合负极材料的循环稳定性。
在一种可行的实施方式中，所述制备方法满足以下条件a～f的至少一者：
a.所述硅氧材料包括SiO x，其中，0<x<2；
b.所述硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至少一种，其中，0<y<2且x≠y，m≥1，n≥1；
c.所述硅氧材料中氧的质量百分含量为0.1％～50％；
d.所述硅氧材料中硅晶粒尺寸为1nm～100nm；
e.所述硅氧材料的比表面积小于100m 2/g；
f.所述硅氧材料的孔隙率φ a<10％。
在一种可行的实施方式中，所述制备方法满足以下条件a～d的至少一者：
a.所述保护性气氛包括氮气、氦气、氖气、氩气、氪气和氙气中的至少一种；
b.所述第一脂肪烃气体和所述第二脂肪烃气体各自独立的包括乙炔、乙烯、丙炔、乙烷和丙烯中的至少一种；
c.所述第二脂肪烃气体与所述硅氧材料的重量比A满足以下关系：1.5φ a/(1-φ a)≤A≤15φ a/(1-φ a)，其中，φ a为所述硅氧材料的孔隙率；
d.所述第一脂肪烃气体和所述第二脂肪烃气体的气体流量各自独立的为0.1L/min～5L/min。
在一种可行的实施方式中，所述制备方法满足以下条件a～e的至少一者：
a.所述预热温度为100℃～600℃；
b.所述预热时间为0.5h～24h；
c.所述化学气相沉积的反应温度为600℃～1050℃；
d.所述间歇脉冲的间隔时间为8s～12s。
e.所述间歇脉冲的脉冲时长为8s～1min。
在一种可行的实施方式中，所述方法还包括：
对沉积得到的所述复合负极材料进行冷却及筛分使得所述复合负极材料的平均粒径为1.0μm～50μm。
第三方面，本申请提供一种锂离子电池，所述锂离子电池包含如上述第一方面所述的复合负极材料或根据上述第二方面所述的制备方法制得的复合负极材料。
本申请的技术方案至少具有以下有益的效果：
1)本申请提供的复合负极材料，硅氧材料的物理吸脱附等温线类型为IV型或V型，使得其与碳的结合点更多，与碳包覆层能更紧密地结合，有利于嵌脱锂过程中电子传导和离子传导；复合负极材料的物理吸脱附等温线类型为II型或III型，说明复合负极材料比较密实，结构稳定，能够保证在活性硅脱嵌锂过程中保持颗粒的完整性，抑制颗粒粉化，提升硅氧材料稳定性，有利于长循环，从整体上改善成品电池的循环稳定性。
2)本申请提供的复合负极材料的制备方法，先通过预热，使得第一脂肪烃气体能够吸附在物理吸脱附等温线类型为IV型或V型的硅氧材料颗粒的孔隙内，从而填充硅氧材料的孔隙，间歇式脉冲通入第二脂肪烃气体，不会导致局部碳源过多沉积，第二脂肪烃气体在裂解时分解成零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密，更有利于形成密实结构且呈球形或类球形的复合负极材料颗粒，有利于负极材料导电网络的完整及结构的稳定性，有利于提高复合负极材料的循环稳定性。并且，制备方法简单易操作，制备过程安全、高效；制造成本有效降低，适于量化生产；制得的产物用作电池极片使用，有利于嵌脱锂过程中电子传导和离子传导，有利于提高电池循环稳定性。
附图说明
图1为本申请实施例提供的复合负极材料的制备方法流程图；
图2为本申请实施例1提供的复合负极材料的物理吸脱附等温线示意图；
图3为本申请实施例1提供的硅氧材料的物理吸脱附等温线示意图；
图4为本申请对比例1提供的复合负极材料的物理吸脱附等温线示意图。
具体实施方式
以下所述是本申请实施例的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本申请实施例原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也视为本申请实施例的保护范围。
第一方面，本申请提供一种复合负极材料，复合负极材料包括硅氧材料和位于硅氧材料表面的碳包覆层；复合负极材料的物理吸脱附等温线类型为II型或III型，硅氧材料的物理吸脱附等温线类型为IV型或V型。
本申请中，物理吸脱附等温线类型的分类依据是国际纯粹与应用化学联合会(IUPAC)提出的物理吸脱附等温线分类方法。
在上述方案中，本申请提供的复合负极材料，硅氧材料的物理吸脱附等温线类型为IV型或V型，与碳包覆层能更紧密地结合，有利于嵌脱锂过程中电子传导和离子传导，有利于提高材料的首效、容量和循环稳定性；复合负极材料的物理吸脱附等温线类型为II型或III型，说明复合负极材料具有密实结构，碳包覆层具有一定的机械强度，结构稳定，能够保证在活性硅脱嵌锂过程中保持颗粒的完整性，抑制颗粒粉化，提升硅氧材料稳定性，进一步从整体上改善材料的循环性能。
以下作为本申请优选的技术方案，但不作为对本申请提供的技术方案的限制，通过以下优选的技术方案，可以更好的达到和实现本申请的技术目的和有益效果。
在一些实施方式中，硅氧材料包括SiO x，其中，0<x<2；SiO x具体可以为SiO 0.5、SiO 0.8、SiO 0.9、SiO、SiO 1.1、SiO 1.2或SiO 1.5等。优选地，硅氧材料为SiO。可以理解地，SiO x的组成比较复杂，可以理解为由纳米硅均匀分散在SiO 2中形成。
在一些实施方式中，硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至少一种，其中，0<y<2且x≠y，m≥1，n≥1。
在一些实施方式中，硅氧材料中硅晶粒尺寸为1nm～100nm；具体可以是1nm、10nm、20nm、40nm、45nm、50nm、55nm、60nm、65nm、70nm、75nm、80nm或100nm等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。可以理解地，硅氧材料的硅晶粒尺寸控制在上述范围内，有利于提高负极材料的结构稳定性、热稳定性和长循环稳定性。需要说明的是，硅氧材料中的硅晶粒尺寸是通XRD图谱测得28.6°Si(111)峰的半峰宽，并利用谢乐公式计算得到。
在一些实施方式中，硅氧材料中氧的质量百分含量为0.1％～50％，具体可以是0.1％、1％、10％、20％、25％、30％、35％、40％或50％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。当硅氧材料中的氧含量过高时，会导致材料容量下降，首次库伦效率下降；当硅氧材料中的氧含量过低时，即硅含量增高，容易导致材料在循环过程中容易膨胀，导致材料粉化严重。
在一些实施方式中，硅氧材料的比表面积小于100m 2/g；具体可以是1.50m 2/g、2.50m 2/g、3.50m 2/g、5.00m 2/g、10m 2/g、50m 2/g或90m 2/g等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。复合负极材料的比表面积在上述范围内，保证了材料的加工性能，有利于提高由该负极材料制成的锂电池的首次效率，有利于提高负极材料的循环性能。
在一些实施方式中，硅氧材料的孔隙率φ a<10％，具体可以是1％、2％、3％、5％、6％、8％或9％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。当硅氧材料孔隙率过高时，不利于形成密实结构的复合材料，不利于提高材料循环稳定性，优选地，硅氧材料的孔隙率1％<φ a<10％。
在一些实施方式中，复合负极材料呈球形或类球形，其沃德尔球形度系数大于0.01，具体可以是0.02、0.04、0.08、0.1、0.15、0.2、0.25、0.3、0.5、0.6、0.8、0.9、0.95或0.99，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。可选地，复合负极材料的沃德尔形度系数为0.1～0.3。当复合负极材料沃德尔球形度系数过低时，颗粒稳定性差，在循环过程中容易粉化，循环膨胀率增大。
在一些实施方式中，复合负极材料的比表面积为1m 2/g～50m 2/g；具体可以是1m 2/g、10m 2/g、15m 2/g、20m 2/g、25m 2/g、30m 2/g、35m 2/g、40m 2/g、45m 2/g或50m 2/g等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。复合负极材料的比表面积在上述范围内，保证了材料的加工性能，有利于提高由该负极材料制成的锂电池的首次效率，有利于提高负极材料的循环性能。
在一些实施方式中，复合负极材料的平均粒径1.0μm～50μm，具体可以是1.0μm、2.0μm、3.0μm、4.0μm、5.0μm、10μm、15μm、20μm、30μm或50μm等。复合负极材料的平均粒径控制在上述范围内，有利于负极材料循环性能的提升。优选地，复合负极材料的平均粒径为1.0μm～10μm。复合负极材料的平均粒径过大导致材料循环性能下降，倍率性能下降，电池首次效率下降。
在一些实施方式中，复合负极材料的孔隙率小于10％；具体可以是0.5％、1.0％、2.0％、3％、4％、5％、6％、7％、8％、9％或9.9％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。将复合负极材料的孔隙率控制在上述范围内，会使材料具有良好的倍率性能。
在一些实施方式中，复合负极材料中碳的质量百分含量为0.1％～50％；具体可以是0.1％、3.0％、5.0％、10.0％、15.5％、20％、30％或50％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。碳含量过高，锂离子传输效率降低，不利于材料大倍率充放电，降低负极材料的综合性能，碳含量过低，不利于增加负极材料的导电性且对材料的体积膨胀抑制性能较弱，导致长循环性能价差。优选地，复合负极材料中的碳的质量百分比含量为1％～10％。
在一些实施方式中，在拉曼光谱中，复合负极材料具有碳特征峰D、碳特征峰G及硅特征峰A，碳特征峰D的峰强度I D与碳特征峰G的峰强度I G的比值I D/I G为0.5～2，具体可以是0.5、0.8、1.0、1.2、1.5、1.8或2.0等等，当I D/I G比值过大时，复合负极材料首次效率下降；当I D/I G比值过小时，复合负极材料的倍率性能下降。I D/I G值在此 范围时，表明碳层由链状碳链裂解而成，不易生成石墨片层。
在一些实施方式中，硅特征峰A的峰强度I A与(I D+I G)的比值为0.1～10，具体可以是0.1、0.2、0.3、0.5、0.6、0.8或1.0等等，当I A/(I D+I G)比值过大时，复合负极材料的循环性能下降；当I A/(I D+I G)比值过小时，复合负极材料的放电比容量下降，不利于提高电池的能量密度。I A/(I D+I G)值在此范围内是，碳包覆层紧密，硅不容易裸露在碳层之外。
第二方面，如图1所示，本申请提供一种复合负极材料的制备方法，包括以下步骤：
步骤S100，在保护性气氛下，通入第一脂肪烃气体，将硅氧材料和所述第一脂肪烃气体进行预热，其中，所述硅氧材料的物理吸脱附等温线类型为IV型或V型；
步骤S200，以间歇脉冲方式通入第二脂肪烃气体，使所述第二脂肪烃气体在所述预热后的产物上进行化学气相沉积，得到复合负极材料。
在上述方案中，先通过预热，使得第一脂肪烃气体能够吸附在物理吸脱附等温线类型为IV型或V型的硅氧材料颗粒的孔隙内，从而填充硅氧材料的孔隙，硅氧材料的物理吸脱附等温线类型为IV型或V型，更有利于第一脂肪烃气体沉积在孔隙中，间歇式脉冲通入第二脂肪烃气体，不会导致局部碳源过多沉积，第二脂肪烃气体在裂解时分解成零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密，更有利于形成密实结构且球形或类球形的复合负极材料颗粒，有利于负极材料导电网络的完整及结构的稳定性，有利于提高复合负极材料的循环稳定性。
以下详细介绍本方案提供的制备方法：
步骤S100，在保护性气氛下，通入第一脂肪烃气体，将硅氧材料和所述第一脂肪烃气体进行预热。
在一些实施方式中，硅氧材料包括SiO x，其中，0<x<2；更具体地，可以是SiO x具体可以为SiO 0.5、SiO 0.8、SiO 0.9、SiO、SiO 1.1、SiO 1.2或SiO 1.5等。优选地，硅氧材料为SiO。可以理解地，SiO x的组成比较复杂，可以理解为由纳米硅均匀分散在SiO 2中形成。
在一些实施方式中，所述硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至少一种，其中，0<y<2且x≠y，m≥1，n≥1。
在一些实施方式中，硅氧材料中硅晶粒尺寸为1nm～100nm；具体可以是1nm、10nm、20nm、40nm、45nm、50nm、55nm、60nm、65nm、70nm、75nm、80nm或100nm等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。可以理解地，硅氧材料的硅晶粒尺寸控制在上述范围内，有利于提高负极材料的结构稳定性、热稳定性和长循环稳定性。需要说明的是，硅氧材料中的硅晶粒尺寸是通XRD图谱测得28.6°Si(111)峰的半峰宽，并利用谢乐公式计算得到。
在一些实施方式中，硅氧材料中氧的质量百分含量为0.1％～50％，具体可以是0.1％、 1％、10％、20％、25％、30％、35％、40％或50％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。当硅氧材料中的氧含量过高时，会导致材料容量下降，首次库伦效率下降会；当硅氧材料中的氧含量过低时，即硅含量增高，容易导致材料在循环过程中容易膨胀，导致材料粉化严重。
在一些实施方式中，硅氧材料的比表面积小于100m 2/g；具体可以是1.50m 2/g、2.50m 2/g、3.50m 2/g、5.00m 2/g、10m 2/g、50m 2/g或100m 2/g等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。复合负极材料的比表面积在上述范围内，保证了材料的加工性能，有利于提高由该负极材料制成的锂电池的首次效率，有利于提高负极材料的循环性能。
在一些实施方式中，硅氧材料的孔隙率φ a<10％，具体可以是1％、2％、3％、5％、6％、8％或10％等等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。当硅氧材料孔隙率过高时，不利于形成密实结构的复合材料，不利于提高材料循环稳定性。
在一些实施方式中，保护性气氛包括氮气、氦气、氖气、氩气、氪气和氙气中的至少一种。在保护性气氛下进行热处理，可以提高反应安全性。
在一些实施方式中，第一脂肪烃气体包括乙炔、乙烯、丙炔、乙烷和丙烯中的至少一种。
在一些实施方式中，第一脂肪烃气体的气体流量为0.1L/min～5L/min，具体可以是0.1L/min、0.5L/min、1L/min、1.5L/min、2L/min、2.5L/min、3L/min、3.5L/min或5L/min等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。
在一些实施方式中，预热温度为100℃～600℃，具体可以是100℃、200℃、300℃、350℃、400℃、450℃、500℃、550℃或600℃等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。预热时间为0.5h～24h；具体可以是0.5h、1.0h、1.5h、3h、5h、6h、8h、12h、15h、18h或24h等，可以理解地，通过充分预热，使得第一脂肪烃气体能够吸附至硅氧材料内部的孔隙内及其表面，有利于形成致密的碳包覆层。优选地，预热温度为400℃～600℃，预热时间为1h～5h。
步骤S200，以间歇脉冲方式通入第二脂肪烃气体，使所述第二脂肪烃气体在所述预热后的产物上进行化学气相沉积，得到复合负极材料。
第二脂肪烃气体裂解时分解成为零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密，更有利于形成密实结构的复合负极材料，有利于材料导电网络的完整及结构的稳定性，有利于提高复合负极材料的循环稳定性。若采用常规的固相碳源，如成份为含芳香环或高级脂肪烃的有机物，其沸点一般高于分解点，裂解时分解成为二维的碳环或长碳链，互相堆叠的紧密度不如零维的单个碳原子自由基或一维的较短碳链，孔径分析得到的物理吸脱附等温线存在迟滞环。而采用芳香烃气体，如苯蒸气，裂解后成为二维的碳环，其堆叠的紧密度也不及一维短碳链或零维的碳原子，孔径分析得到的物理吸脱附等温线存在迟滞环，不利于保持负极材料的循环稳定性。
在一些实施方式中，第二脂肪烃气体与硅氧材料的重量比A满足以下关系：1.5φ a/(1-φ a)≤A≤15φ a/(1-φ a)，其中，φ a为硅氧材料的孔隙率。通过通入适量的第 二脂肪烃气体，有利于在硅氧材料表面沉积形成均匀的碳包覆层，且使得碳包覆层包裹的硅氧材料能够形成密实结构，降低硅氧材料的孔隙率。
在一些实施方式中，第二脂肪烃气体包括乙炔、乙烯、丙炔、乙烷和丙烯中的至少一种。
在一些实施方式中，第二脂肪烃气体的气体流量为0.1L/min～5L/min，具体可以是0.1L/min、0.5L/min、1L/min、1.5L/min、2L/min、2.5L/min、3L/min、3.5L/min或5L/min等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。
在一些实施方式中，化学气相沉积的反应温度为600℃～1050℃，具体可以是600℃、700℃、800℃、850℃、900℃、950℃、1000℃或1050℃等，但并不仅限于所列举的数值，该数值范围内其他未列举的数值同样适用。可以理解地，通过化学气相沉积，第二脂肪烃气体裂解时分解成为零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密，更有利于形成密实结构的复合负极材料，有利于材料导电网络的完整及结构的稳定性，有利于提高复合负极材料的循环稳定性。优选地，化学气相沉积的反应温度为800℃～1000℃。
在一些实施方式中，在化学气相沉积过程中，以间歇脉冲方式继续通过脂肪烃气体，间歇脉冲的间隔时间为8s～12s。
在一些实施方式中，间歇脉冲的脉冲时长为8s～1min。脉冲时长具体可以是每隔10s通入10s的脂肪烃气体。通过间歇式脉冲方式通入碳源气体(第二脂肪烃气体)，不容易导致硅氧材料表面的碳源局部过多沉积，有利于提高硅氧材料表面的碳包覆层的均匀性，有利于形成均匀致密的碳包覆层。若采用连续通入第二脂肪烃气体的方式，不利于生成复合负极材料的物理吸脱附等温线类型为II型或III型结构，不利于提高负极材料的循环稳定性。
在一些实施方式中，在步骤S200之后，方法还包括：
对沉积得到的复合负极材料进行冷却及筛分使得复合负极材料的平均粒径为1.0μm～50μm，具体可以是1μm、5μm、10μm、15μm、20μm、30μm、40μm或50μm等。复合负极材料的平均粒径控制在上述范围内，有利于负极材料循环性能的提升。优选地，复合负极材料的平均粒径为1μm～10μm。
在一些实施方式中，筛分包括破碎、球磨、筛选或分级中的至少一种。
第三方面，本申请提供一种锂离子电池，锂离子电池包含上述第一方面的复合负极材料或上述第二方面的制备方法制得的复合负极材料。
下面分多个实施例对本申请实施例进行进一步的说明。其中，本申请实施例不限定于以下的具体实施例。在保护范围内，可以适当的进行变更实施。
实施例1
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S1包括硅氧材料和位于硅氧材料表面的碳包覆层。复合负极材料的物理吸脱附等温线如图2所示，可以看出其物理吸脱附等温线类型为II型；将复合负极材料中的碳元素灼烧去除后，测得硅氧材料的物理吸脱附等温线如图3所示，其物理吸脱附等温线类型为IV型。
实施例2
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 3H 6处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 3H 6。通过流量计读数和时间，控制C 3H 6通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S2包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例3
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为V型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至300℃，通入C 3H 4处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 3H 4。通过流量计读数和时间，控制C 3H 4通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S3包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例4
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至300℃，通入C 2H 2处理12h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S4包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例5
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为200g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S5包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例6
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为1000g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S6包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例7
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO 0.8材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO 0.8材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S7包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例8
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO 1.5材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO 1.5材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S8包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例9
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为75g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S9包括硅氧材料和位于硅氧材料表面的碳包覆层。
实施例10
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 3H 4处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本实施例制得的复合负极材料S10包括硅氧材料和位于硅氧材料表面的碳包覆层。
对比例1
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率 5％，物理吸脱附等温线类型为II型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入苯蒸气C 6H 6处理2h；
(3)再将回转炉升温至800℃后，每隔10s通入10s C 6H 6。通过流量计读数和时间，控制C 6H 6通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本对比例制得的复合负极材料D1包括硅氧材料和位于硅氧材料表面的碳包覆层。复合负极材料的物理吸脱附等温线如图4所示，其物理吸脱附等温线类型为IV型。
对比例2
一种复合负极材料的制备方法，包括以下步骤：
(1)将Si与SiO 2进行真空沉积反应，得到的SiO材料，然后挑选950g孔隙率5％，物理吸脱附等温线类型为IV型的SiO材料；
(2)取上述SiO材料置于回转炉A中，往回转炉A通入Ar保护气后，升温至500℃，通入C 2H 2处理2h；
(3)再将回转炉升温至800℃后，连续通入C 2H 2。通过流量计读数和时间，控制C 2H 2通入总量为100g；
(4)反应结束后将样品冷却取出，使用破碎机打散，得到复合负极材料。
本对比例制得的复合负极材料D2包括硅氧材料和位于硅氧材料表面的碳包覆层。复合负极材料D2的物理吸脱附等温线类型为IV型。
性能参数测试
1.将上述实施例以及对比例制得的复合负极材料分别使用氧氮氢分析仪，测得除碳后的硅氧材料氧含量如表1所示；
2.将上述实施例以及对比例制得的复合负极材料分别使用激光粒度仪测得复合负极材料的平均粒径如表1所示；
3.将上述实施例以及对比例制得的复合负极材料分别使用BET法氮吸附比表面积仪测得材料的比表面积如表1所示；
4.将上述实施例以及对比例制得的复合负极材料分别使用测得的比表面积以及平均粒径计算得到材料颗粒的wadell(沃德尔)球形度，具体数值如表1所示；
5.将上述实施例以及对比例制得的复合负极材料分别使用氮吸附孔径分析仪在1.7nm～300nm孔径范围测试复合负极材料的孔径分布，得到物理吸脱附等温线及孔隙率，其物理吸脱附等温线在p/p0在0～1区间内是否存在迟滞环以及其物理吸脱附等温线类型，结果如表1所示；
6.将上述实施例以及对比例制得的复合负极材料分别使用拉曼光谱仪测得拉曼光谱，在拉曼光谱中，所述复合负极材料具有碳特征峰D、碳特征峰G及硅特征峰A，所述碳特征峰D的峰强度I D与所述碳特征峰G的峰强度I G的比值I D/I G，以及所述硅 特征峰A的峰强度I A与(I D+I G)的比值，如表1所示；
7.将上述实施例以及对比例制得的复合负极材料使用X射线衍射分析仪进行分析，能观察到Si特征峰，对28～30°的Si(111)峰进行拟合，再使用谢勒公式计算硅氧材料的粒径尺寸，如表1所示；
8.将上述实施例以及对比例制得的复合负极材料使用使用微量碳分析仪进行分析，得到复合负极材料的碳的质量百分比含量如表1所示；
9.上述实施例以及对比例制得的复合负极材料分别置于300度空气氛电炉下进入处理，直至恒重，且使用微量碳分析仪测得其碳含量<0.1％时，得到的除碳处理后的硅氧材料。使用氮吸附孔径分析仪在1.7nm～300nm孔径范围测试硅氧材料的孔径分布，得到物理吸脱附等温线及孔隙率，其物理吸脱附等温线在p/p0在0～1区间内是否存在迟滞环以及其物理吸脱附等温线类型，结果如表1所示；
10.将除碳处理后的硅氧材料分别使用BET法氮吸附比表面积仪测得材料的比表面积如表1所示；
11.将除碳处理后的硅氧材料分别使用氧氮氢分析仪，测得硅氧材料的氧含量如表1所示；
12.将上述制得的复合负极材料分别使用过量的氢氟酸和浓硝酸组成的混酸进行处理，直至继续添加混酸并放置30min后也不放出红棕色气体时，将材料抽滤并烘干，得到的处理后的材料即为碳包覆层。使用氮吸附孔径分析仪在1.7nm～300nm孔径范围测试碳包覆层的孔径分布，得到物理吸脱附等温线及孔隙率，其物理吸脱附等温线在p/p0在0～1区间内是否存在迟滞环以及其物理吸脱附等温线类型，结果如表1所示；
13.将上述制得的碳包覆层进行充放电测试，得到碳包覆层的充放电容量，结果如表1所示。
14.将上述制得的碳包覆层分别使用拉曼光谱仪测得拉曼光谱，在拉曼光谱中，所述碳包覆层具有碳特征峰D、碳特征峰G，所述碳特征峰D的峰强度ID与所述碳特征峰G的峰强度IG的比值ID/IG，如表1所示。
表1.复合负极材料性能参数结果表
Figure PCTCN2021128547-appb-000001
Figure PCTCN2021128547-appb-000002
进一步地，将本实施例1～10以及对比例1～2制得的负极材料和导电炭黑和PAA胶按质量比75:15:10调制成负极浆料，在铜箔上涂布，干燥后制成负极极片。以金属锂片作为对电极，在充满氩气的手套箱中组装成扣式电池完成。在0.1C的电流密度下，按充放电区间为0.01-1.5V进行充放电测试。测试得到电池的首次可逆比容量，首次效率以及循环50圈后容量保持率。
锂离子电池性能测试
1.对上述12组电池在蓝电CT2001A电池测试系统上进行放电比容量测试，1小时放电的电量与电池容量的比为首次放电比容量，结果如表2所示。
2.对上述12组电池在蓝电CT2001A电池测试系统上进行首次库伦效率测试，充放电电流为0.05C，测得首次库伦效率，结果如表2所示。
3.对上述12组电池在蓝电CT2001A电池测试系统上进行循环50周测试，充放电电流为0.2C，循环50圈后测试计算圈后电池容量及圈后容量保持率。
其中，0.2C循环50圈后容量保持率＝第50圈循环放电容量/第一周放电容量*100％，结果如表2所示。
表2.锂离子电池性能比对结果表
Figure PCTCN2021128547-appb-000003
由上表1～2可知，实施例1至8采用先预热，使得第一脂肪烃气体能够吸附在硅氧材料颗粒的孔隙内，从而填充硅氧材料的孔隙，间歇式脉冲通入第二脂肪烃气体，不会导致局部碳源过多沉积，第二脂肪烃气体在裂解时分解成零维的单个碳原子自由基或一维的较短碳链，互相堆叠会更紧密。如图2至图3所示，实施例1的复合负极材料的物理吸脱附等温线为II型，实施例1的硅氧材料物理吸脱附等温线为IV型。并且，实施例2至8制得的复合负极材料的物理吸脱附等温线类型为II型或III型，说明复合负极材料比较密实，结构稳定，能够保证在活性硅脱嵌锂过程中保持颗粒的完整性，抑制颗粒粉化，由其制成的电池循环稳定性有效提高。
实施例6中的第二脂肪烃气体通入过量，第二脂肪烃气体与硅氧材料的重量比A大于0.79，即15φ a/(1-φ a)＝0.79，说明过量的第二脂肪烃气体会导致硅氧材料的局部碳源过多沉积，负极活性物质(硅氧材料)的质量占比减少，负极材料的首次放电比容量以及首次库伦效率明显下降。
实施例9中的第二脂肪烃气体通入偏少，第二脂肪烃气体与硅氧材料的重量比A等于0.079，即1.5φ a/(1-φ a)＝0.079，导致硅氧材料表面沉积的碳源过少，负极材料导电性下降，首次放电比容量以及首次库伦效率、循环保持率均相比于实施例1有所下降。
对比例1与实施例1的主要区别在于，化学气相沉积时通入的第二脂肪烃气体为苯蒸气，苯蒸气(C 6H 6)裂解后成为二维的碳环，其堆叠的紧密度不及乙烯裂解形成的一维短碳链或零维的碳原子，包覆后的复合负极材料经过孔径分析的物理吸脱附等温线存在迟滞环，如图4所示，其物理吸脱附等温线为IV型，对比例1的循环容量保持率低于实施例1的循环容量保持率。
对比例2与实施例1的主要区别在于，化学气相沉积时连续通入第二脂肪烃气体，没有采用间歇式脉冲形式通入，导致硅氧材料表面的碳源局部过多沉积，不有利于提高硅氧材料表面的碳包覆层的均匀性，制成的复合负极材料的物理吸脱附等温线类型为IV型，对比例2的循环容量保持率低于实施例1的循环容量保持率，不利于提高负极材料的循环稳定性。
综上所述，本申请提供复合负极材料的制备方法，简单易操作，制备过程安全、高效；制造成本有效降低，适于量化生产；制得的产物用作电池极片使用，有利于嵌脱锂过程中电子传导和离子传导，有利于提高电池循环稳定性。
本申请虽然以较佳实施例公开如上，但并不是用来限定权利要求，任何本领域技术人员在不脱离本申请构思的前提下，都可以做出若干可能的变动和修改，因此本申请的保护范围应当以本申请权利要求所界定的范围为准。

Claims (10)

  1. 一种复合负极材料，其特征在于，所述复合负极材料包括硅氧材料和位于所述硅氧材料表面的碳包覆层；所述复合负极材料的物理吸脱附等温线类型为II型或III型，所述硅氧材料的物理吸脱附等温线类型为IV型或V型。
  2. 根据权利要求1所述的复合负极材料，其特征在于，在拉曼光谱中，所述复合负极材料具有碳特征峰D、碳特征峰G及硅特征峰A，所述碳特征峰D的峰强度I D与所述碳特征峰G的峰强度I G的比值I D/I G为0.5～2，且所述硅特征峰A的峰强度I A与(I D+I G)的比值为0.1～10。
  3. 根据权利要求1所述的复合负极材料，其特征在于，其满足以下条件a～f的至少一者：
    a.所述硅氧材料包括SiO x，其中，0<x<2；
    b.所述硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至少一种，其中，0<y<2且x≠y，m≥1，n≥1；c.所述硅氧材料中氧的质量百分含量为0.1％～50％；
    d.所述硅氧材料中硅晶粒尺寸为1nm～100nm；
    e.所述硅氧材料的比表面积小于100m 2/g；
    f.所述硅氧材料的孔隙率φ a<10％。
  4. 根据权利要求1～3任一项所述的复合负极材料，其特征在于，其满足以下条件a～e的至少一者：
    a.所述复合负极材料颗粒呈球形或类球形，其沃德尔球形度系数大于0.01；
    b.所述复合负极材料的平均粒径为1.0μm～50μm；
    c.所述复合负极材料的孔隙率小于10％；
    d.所述复合负极材料的比表面积为1m 2/g～50m 2/g；
    e.所述复合负极材料中碳的质量百分含量为0.1％～50％。
  5. 一种复合负极材料的制备方法，其特征在于，所述方法包括以下步骤：
    在保护性气氛下，通入第一脂肪烃气体，将硅氧材料和所述第一脂肪烃气体进行预热，其中，所述硅氧材料的物理吸脱附等温线类型为IV型或V型；
    以间歇脉冲方式通入第二脂肪烃气体，使所述第二脂肪烃气体在所述预热后的产物上进行化学气相沉积，得到所述复合负极材料。
  6. 根据权利要求5所述的制备方法，其特征在于，其满足以下条件a～f的至少一者：
    a.所述硅氧材料包括SiO x，其中，0<x<2；
    b.所述硅氧材料还包括SiO x的复合材料，所述SiO x的复合材料包括SiO x复合SiO y、SiO x复合SiO 2、SiO x复合Li mSiO n、SiO x复合Na mSiO n、SiO x复合K mSiO n、SiO x复合Mg mSiO n、SiO x复合Ca mSiO n、SiO x复合Al mSiO n、SiO x复合无定型碳、SiO x复合石墨、SiO x复合石墨烯、SiO x复合碳纳米管和SiO x复合高分子材料中的至 少一种，其中，0<y<2且x≠y，m≥1，n≥1；
    c.所述硅氧材料中氧的质量百分含量为0.1％～50％；
    d.所述硅氧材料中硅晶粒尺寸为1nm～100nm；
    e.所述硅氧材料的比表面积小于100m 2/g；
    f.所述硅氧材料的孔隙率φ a<10％。
  7. 根据权利要求5所述的制备方法，其特征在于，其满足以下条件a～d的至少一者：
    a.所述保护性气氛包括氮气、氦气、氖气、氩气、氪气和氙气中的至少一种；
    b.所述第一脂肪烃气体和所述第二脂肪烃气体各自独立的包括乙炔、乙烯、丙炔、乙烷和丙烯中的至少一种；
    c.所述第二脂肪烃气体的通入总质量与所述硅氧材料的重量比A满足以下关系：1.5φ a/(1-φ a)≤A≤15φ a/(1-φ a)，其中，φ a为所述硅氧材料的孔隙率；
    d.所述第一脂肪烃气体和所述第二脂肪烃气体的气体流量各自独立的为0.1L/min～5L/min。
  8. 根据权利要求5或7所述的制备方法，其特征在于，其满足以下条件a～e的至少一者：
    a.所述预热温度为100℃～600℃；
    b.所述预热时间为0.5h～24h；
    c.所述化学气相沉积的反应温度为600℃～1050℃；
    d.所述间歇脉冲的间隔时间为8s～12s；
    e.所述间歇脉冲的脉冲时长为8s～1min。
  9. 根据权利要求5所述的制备方法，其特征在于，所述方法还包括：
    对沉积得到的所述复合负极材料进行冷却及筛分使得所述复合负极材料的平均粒径为1.0μm～50μm。
  10. 一种锂离子电池，其特征在于，所述锂离子电池包含如权利要求1～4任一项所述的复合负极材料或根据权利要求5～9任一项所述的制备方法制得的复合负极材料。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2025537608A (ja) * 2023-06-30 2025-11-18 貝特瑞新材料集団股▲ふん▼有限公司 負極材料及びその製造方法、並びにリチウムイオン電池

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113066985A (zh) * 2021-03-29 2021-07-02 贝特瑞新材料集团股份有限公司 复合负极材料及其制备方法、锂离子电池
CN116500015B (zh) * 2023-06-28 2023-08-29 北京壹金新能源科技有限公司 一种硅基复合材料制备的质量监控方法
WO2025199684A1 (zh) * 2024-03-25 2025-10-02 宁德新能源科技有限公司 一种二次电池及其制备方法、电子装置
CN120504320A (zh) * 2025-07-18 2025-08-19 深圳索理德新材料科技有限公司 多孔硅碳负极材料及其制备系统和制备方法、锂离子电池

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103280560A (zh) * 2013-05-20 2013-09-04 北京科技大学 一种锂离子电池介孔氧化亚硅碳复合负极材料的制备方法
CN104993102A (zh) * 2015-05-19 2015-10-21 长安大学 介孔非晶SiOX/C纳米复合的负极材料制备方法
CN106797026A (zh) * 2014-10-08 2017-05-31 信越化学工业株式会社 非水电解质二次电池、其负极、其负极活性物质及其负极材料的制造方法
US20200044239A1 (en) * 2018-07-18 2020-02-06 Daegu Gyeongbuk Institute Of Science And Technology Porous inorganic insulator-sulfur composite, and lithium-sulfur battery comprising the same
CN113066985A (zh) * 2021-03-29 2021-07-02 贝特瑞新材料集团股份有限公司 复合负极材料及其制备方法、锂离子电池

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4724877B2 (ja) * 2005-01-28 2011-07-13 独立行政法人物質・材料研究機構 炭素多孔体、炭素多孔体を製造する方法、吸着剤および生体分子素子
CN100371302C (zh) * 2006-05-26 2008-02-27 中国科学院上海硅酸盐研究所 气相渗硅工艺制备碳纤维增强碳化硅基复合材料的方法
JP5665127B2 (ja) * 2011-04-28 2015-02-04 国立大学法人東北大学 表面を炭素被覆されたシリカ材料の製造方法、該製造方法により製造された炭素被覆シリカ材料及びその用途
CN104254490B (zh) * 2011-11-30 2016-12-21 上海交通大学 用作锂离子电池负极材料的介孔硅/碳复合材料以及其制备方法
CN103094534B (zh) * 2012-12-21 2015-08-26 顾向红 一种高比容量锂离子电池负极材料的制备方法
DE102016202459A1 (de) * 2016-02-17 2017-08-17 Wacker Chemie Ag Kern-Schale-Kompositpartikel
JP6772429B2 (ja) * 2016-03-24 2020-10-21 国立大学法人信州大学 複合ナノ繊維の製造方法
JP2018206560A (ja) * 2017-06-01 2018-12-27 信越化学工業株式会社 負極活物質、混合負極活物質材料、及び、負極活物質粒子の製造方法
US11999624B2 (en) * 2017-09-29 2024-06-04 Lg Energy Solution, Ltd. Yolk-shell structured particles, method for producing same, and lithium secondary battery comprising same
CN111656584A (zh) * 2018-01-31 2020-09-11 日立化成株式会社 锂离子二次电池用负极活性物质、锂离子二次电池用负极和锂离子二次电池
CN111162268B (zh) * 2019-09-26 2021-06-18 贝特瑞新材料集团股份有限公司 一种复合负极材料及其制备方法和锂离子电池
CN111029543B (zh) * 2019-11-28 2022-02-15 宁德新能源科技有限公司 负极材料及包含其的电化学装置和电子装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103280560A (zh) * 2013-05-20 2013-09-04 北京科技大学 一种锂离子电池介孔氧化亚硅碳复合负极材料的制备方法
CN106797026A (zh) * 2014-10-08 2017-05-31 信越化学工业株式会社 非水电解质二次电池、其负极、其负极活性物质及其负极材料的制造方法
CN104993102A (zh) * 2015-05-19 2015-10-21 长安大学 介孔非晶SiOX/C纳米复合的负极材料制备方法
US20200044239A1 (en) * 2018-07-18 2020-02-06 Daegu Gyeongbuk Institute Of Science And Technology Porous inorganic insulator-sulfur composite, and lithium-sulfur battery comprising the same
CN113066985A (zh) * 2021-03-29 2021-07-02 贝特瑞新材料集团股份有限公司 复合负极材料及其制备方法、锂离子电池

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2025537608A (ja) * 2023-06-30 2025-11-18 貝特瑞新材料集団股▲ふん▼有限公司 負極材料及びその製造方法、並びにリチウムイオン電池

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