454results about "Silicon" patented technology

The invention belongs to the field of negative electrode materials, and particularly relates to a silicon-graphite composite material, a preparation method and application thereof and a lithium ion battery, the preparation method comprises the following steps: mixing and slurrying silicon powder, graphite and a composite functional additive, and then carrying out ball milling modification to obtain primary composite particles; the composite functional auxiliary agent comprises an auxiliary agent A, an auxiliary agent B and an auxiliary agent C; the primary composite particles and a carbon source liquid phase are compounded and then subjected to spray drying and heat treatment, or spray pyrolysis is directly carried out, and secondary composite particles are prepared; and carrying out modification treatment on the secondary composite particles prepared in the step 2 in a surface modification liquid, and then carrying out low-temperature annealing at 150-300 DEG C to prepare the silicon-graphite composite material. The surface modification liquid is an organic solution in which conductive lithium salt and an auxiliary agent D are dissolved. Based on the combined control of the preparation process and the structure, the silicon-based negative electrode material with ultra-long cycle life and excellent low-temperature fast charging performance can be obtained.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a preparation method of a graded ordered silicon-carbon negative electrode material for a lithium ion battery, which comprises the following steps: (S1) mixing phenolic resin and a template agent, calcining, and etching to obtain porous carbon containing macropores; (S2) carrying out cracking and carbon coating on the silicon source gas to obtain nano crystalline silicon containing a carbon coating layer; (S3) mixing the porous carbon with the nano crystalline silicon containing the carbon coating layer, and then carrying out ultrasonic vibration, so that macropores of the porous carbon are filled with the nano crystalline silicon to obtain a silicon-carbon composite material I; (S4) treating the silicon-carbon composite material I by using a carbon-containing sealing agent, and then activating to obtain a silicon-carbon composite material II; and (S5) carrying out vapor phase silicon deposition on the silicon-carbon composite material II to fill the amorphous silicon in the pores of the porous carbon, and then carrying out carbon coating to obtain the graded ordered silicon-carbon negative electrode material. The silicon-carbon negative electrode material prepared by the invention is of a composite structure in which crystalline silicon and amorphous silicon are spatially and orderly distributed, so that the structural stability and the uniform distribution of silicon are realized.

The invention provides a preparation method for preparing porous carbon based on an aerogel method, the porous carbon and application of the porous carbon, and belongs to the technical field of porous carbon material preparation. The preparation method comprises the following steps: mixing polyhydroxy phenol, aromatic aldehyde, acrylamide, graphene oxide and lithium salt according to a mass ratio of 100: (50-200): (5-30): (1-5): (1-5), carrying out hydrothermal reaction at 100-200 DEG C for 1-6 hours, and freeze-drying at-40 DEG C to obtain a hydrogel precursor; and carbonizing the precursor in organic heteroatom gas at 500-800 DEG C, mixing the intermediate with alkali according to the ratio of 100: (100-500), activating at 900-1100 DEG C, pickling and drying to obtain the porous carbon. The conductivity of the product is improved by means of graphene, lithium salt and heteroatoms, and the aerogel method obtains large aperture, has the characteristics of low impedance, high first efficiency and small charge-discharge expansion, and can be efficiently applied to silicon-carbon materials.

The application provides a negative electrode material and a preparation method thereof and a secondary battery, and relates to the technical field of battery materials. The negative electrode material comprises a silicon-based inner core and a carbon layer coated on the surface of the silicon-based inner core, wherein the silicon-based inner core comprises nanosilicon and a silicate containing a metal element M; the negative electrode material is subjected to section analysis and energy spectrum analysis, and meets the conditions of k1<=10, k2<=5 and 0.1 The preparation method of the negative electrode material comprises the following steps: heating and evaporating pre-disproportionated silicon monoxide material and M metal source material to obtain silicon monoxide gas and metal source gas; mixing and condensing the two kinds of gas to obtain an inner core material; and performing carbon coating treatment to obtain the negative electrode material. In the negative electrode material prepared by the application, the metal silicate effectively separates the nanosilicon domain and the silicon oxide domain, and is uniformly distributed, and the negative electrode material has high initial efficiency and excellent cycle performance.

This invention provides a material that can serve as a negative electrode active material for manufacturing lithium-ion secondary batteries with excellent capacity and cycle characteristics. [Solution] A negative electrode active material for a lithium-ion secondary battery containing a stacked disordered silicon carbide, an amorphous carbon material, and silicon, wherein the stacked disordered silicon carbide and the silicon are dispersed in the amorphous carbon material such that they have conductive paths with the amorphous carbon material, and the silicon content is 5.0 to 28.0% by mass, with a total amount of 100% by mass, and the stacked disordered silicon carbide content is 21.6 to 57.0% by mass.

According to the silicon powder processing device, a follow-up dust collection mechanism comprises a dust collection pipe, a dust collection opening communicated with the dust collection pipe and a follow-up driving device for driving the dust collection opening to synchronously move along with a laser processing point; the follow-up driving device is a linear module, the linear module comprises a guide rail extending in the machining direction and a sliding block in sliding fit with the guide rail, and the dust suction opening is connected with the sliding block through a fixing frame. The trumpet-shaped flow guide cover at the dust collection opening is better in guidance quality, the wide opening end faces a machining point, the dust collection coverage range is directly enlarged, and the area, prone to dust diffusion, around the machining point can be covered; the narrow opening end is communicated with the dust suction pipe, local negative pressure is directly enhanced through section contraction, dust suction power is improved, and retention and escape of dust in a machining area are reduced. The motion stability of the dust suction inlet moving along with the machining point is directly guaranteed, dust suction position deviation caused by shaking is avoided, it is guaranteed that the dust suction inlet is always aligned with the core area of the machining point, and the stable dust removal effect is maintained.

The invention relates to porous carbon for a silicon-carbon negative electrode material and a preparation method thereof, and the preparation method of the porous carbon for the silicon-carbon negative electrode material comprises the following steps: removing inorganic matters in biochar to less than 100 ppm; the preparation method comprises the following steps: adding biochar and a triblock copolymer F127 into an ethanol solution, and grinding to combine the biochar and the triblock copolymer F127 into a mesostructure to obtain a precursor solution; drying the precursor solution and preparing microsphere particles; adding urea, polyvinyl alcohol and graphene, and uniformly mixing to obtain a porous carbon composite precursor; carbonizing the porous carbon composite precursor; after carbonization is completed, activation is conducted through water vapor, and porous carbon is obtained after activation is completed. According to the porous carbon for the silicon-carbon negative electrode material and the preparation method, the biochar is used as a carbon source, the raw material price is low, and the production cost is reduced.

The invention discloses a preparation method and application of a liquid-phase-coated surface-passivated silicon-carbon negative electrode material based on a fluidized bed product, and belongs to the field of battery negative electrode materials.The preparation method of a silicon-carbon negative electrode comprises the steps that a, the silicon-carbon negative electrode material prepared through a fluidized bed is placed in a fluidized bed reactor; fluidizing gas is introduced, so that the silicon-carbon negative electrode material is in a fluidized state; b) atomizing a coating agent solution containing a carbon precursor and a solvent, and spraying the atomized coating agent solution into the fluidized bed reactor to uniformly coat the surface of the silicon-carbon negative electrode material with the coating agent solution; and c) carrying out heat treatment on the coated silicon-carbon negative electrode material, and converting the carbon precursor into a carbonaceous passivation layer. The method has the advantages of low cost, high efficiency and high quality.

The invention provides a spherical silicon-based composite material and a preparation method thereof, a negative electrode and a battery, and relates to the technical field of silicon-based composite materials, the spherical silicon-based composite material comprises phenolic resin microspheres, a conductive agent and silicon nanoparticles, the phenolic resin microspheres are doped with the conductive agent to form a matrix of the spherical silicon-based composite material, and the silicon nanoparticles are doped with the conductive agent to form the spherical silicon-based composite material. The phenolic resin microspheres are of a regular spherical structure, grooves or protrusions or the combination of the grooves and the protrusions are arranged on the outer surfaces of the phenolic resin microspheres, the conductive agent is evenly dispersed in the phenolic resin microspheres, and part of the conductive agent is dispersed on the outer surfaces of the phenolic resin microspheres. The matrix is activated to form porous carbon microspheres with discontinuous porous channels or pores, and the silicon nanoparticles are deposited in the porous channels or pores. The problems that the ion conduction rate of the spherical silicon-based composite material is reduced and the conductivity is reduced can be solved, so that the first efficiency and the cycle stability of the spherical silicon-based composite material are improved.

The invention provides a nitrogen-fluorine double-element doped porous carbon material, a silicon-carbon negative electrode material and a preparation method thereof, and the preparation method of the porous carbon material comprises the following steps: mixing porous carbon with ammonium fluoride and / or ammonium bifluoride, and carrying out vapor deposition coating or liquid phase coating; and calcining the coated porous carbon material in a closed environment in an inert atmosphere to obtain the nitrogen-fluorine double-element doped porous carbon material. According to the invention, by utilizing the characteristics of nano-scale micropores and super-large specific surface of porous carbon and the properties of low melting point and low boiling point of ammonium fluoride and ammonium bifluoride, a uniformly coated ammonium fluoride and ammonium bifluoride coating layer is obtained by adopting a vapor deposition or liquid phase coating method, and then the porous carbon material is obtained by utilizing high-temperature calcination treatment. According to the present invention, the characteristics of high specific surface and nano-scale micropores can be simultaneously retained, and after the silicon-carbon negative electrode material is prepared, the expansion of the silicon-carbon negative electrode material is substantially reduced, the cycle performance of the material is ensured, and the rate capability of the obtained silicon-carbon negative electrode material is improved.

The invention relates to the technical field of lithium battery material production, in particular to a lithium ion battery silicon-oxygen negative electrode material preparation system and method.The lithium ion battery silicon-oxygen negative electrode material preparation system comprises a transversely-arranged furnace body, the furnace body is internally provided with a preheating area and a high-temperature area, and the lithium ion battery silicon-oxygen negative electrode material preparation system further comprises a two-way conveying part, a driving assembly and a gas guide assembly; the driving assembly is arranged on the furnace body and connected with the two-way conveying piece. Through the arrangement of the two-way conveying part, the driving assembly and the air guide assembly, carrier particles can be preheated before entering a high-temperature area, and the situation that tiny cracks are generated due to the fact that thermal stress on the surfaces of the carrier particles is too large due to sudden temperature difference when the carrier particles enter the high-temperature area is avoided; and meanwhile, the carrier particles can be continuously subjected to'climbing-sliding-re-climbing 'movement in the rotating process of the two-way conveying part, so that full contact between the carrier particles and the reaction gas is ensured, and dual guarantee on the endurance performance of the lithium battery is realized.

The invention discloses petroleum coke, a silicon carbon material, a silicon composite negative electrode material and a preparation method thereof. The preparation method comprises the following steps: carrying out first solid removal treatment on a first heavy oil raw material to obtain first purified heavy oil; carrying out second solid removal treatment on the second heavy oil raw material to obtain second purified heavy oil; mixing the second purified heavy oil with nano-porous silicon to obtain third purified heavy oil and heavy oil containing nano-porous silicon; carrying out spray granulation on the heavy oil containing the nano porous silicon to obtain a silicon-carbon precursor and fourth purified heavy oil; mixing the third purified heavy oil, the fourth purified heavy oil and the first purified heavy oil to obtain heavy mixed oil; carrying out distillation, pyrolysis and modification treatment on the heavy mixed oil to obtain petroleum coke; carbonizing the silicon-carbon precursor to obtain a silicon-carbon material; the silicon composite negative electrode material is prepared from petroleum coke and a silicon carbon material. The petroleum coke and the silicon carbon material with relatively high quality can be prepared, and the electrochemical performance of the negative electrode material can be improved.

The present exemplary embodiments relate to a silicon-based negative electrode active material, a method of preparing the same, and a lithium secondary battery including the same. The silicon-based negative electrode active material according to an exemplary embodiment may have a particle size fraction D1 of 1 µm or more, a D99 of 20 µm or less, and a degree of oxidation of 0.3% to 3.0%.

The invention relates to a device and a method for continuously preparing a silicon-carbon composite negative electrode material based on multiple fluidized beds. The device comprises a carbon activation fluidized bed, a passivation fluidized bed and a silicon deposition and carbon coating fluidized bed which are sequentially connected in series, a first loop gas sealer is arranged between the carbon activation fluidized bed and the passivation fluidized bed; a second loop gas sealer is arranged between the silicon deposition and carbon coating fluidized bed and the passivation fluidized bed; the two ends of the first loop gas sealer and the two ends of the second loop gas sealer are each independently provided with a double-end inert gas sealing nozzle. A top gas outlet of the silicon deposition and carbon coating fluidized bed is connected with a bottom gas inlet of the passivation fluidized bed; the carbon activation fluidized bed is independently provided with a gas inlet and a feeding hole respectively; a gas inlet and a discharge hole are formed in the bottom of the silicon deposition and carbon coating fluidized bed. The device disclosed by the invention can realize continuous production of the silicon-carbon composite negative electrode material, and the production efficiency and the process safety are greatly improved.

The invention belongs to the technical field of preparation of nano silicon materials, and particularly relates to a method for preparing nano silicon by etching a silicon-aluminum alloy and a nano silicon material thereof. Comprising the following steps: placing a pretreated silicon-aluminum alloy sample wafer in an etching tank containing a main etching solution, etching under the action of an alternating pulse electric field and ultrasonic-megasonic coupling, and adjusting the pH value to 2.5-3.0 by using acetic acid; quickly washing the silicon-aluminum alloy sample wafer subjected to main etching, putting the silicon-aluminum alloy sample wafer into an electrolytic cell containing a composite buffer solution of oxalic acid and sulfuric acid, and performing electrochemical fine etching under a direct-current constant-voltage electric field; and when the etching current density is reduced to 10% of the initial value, the reaction is terminated, and after low-temperature treatment and low-temperature vacuum drying, the nano silicon material with the residual Al content of 8-12 wt% and the O / Si atomic ratio of 0.15-0.25 is obtained. According to the invention, the problems of out-of-control components, structural damage and serious pollution in the prior art are solved, and the nano silicon material with controllable residual aluminum element and low oxygen-silica ratio can be stably prepared.

A negative electrode active material for a lithium secondary battery, according an embodiment of the present invention, comprises a silicon carbon (Si / C) composite having a modulus value (A) of 15-25 GPa and a hardness value (B) of 2500-5000 MPa.

This invention relates to the field of lithium battery anode material technology, specifically a polymer sieving interface silicon-carbon anode material for all-solid-state batteries, its preparation method, and its application. It comprises a porous carbon material matrix with micropores / mesoporous pores of 1-5 nm in diameter. A silicon-carbon composite matrix is ​​first formed by depositing a 1-2 nm diameter nano-silicon layer within the pores of the porous carbon material matrix. Then, a polymer layer is deposited on the surface of the silicon-carbon composite matrix to form a silicon-carbon anode material with nano-confined pores and a polymer sieving interface layer of 2-50 nm thickness and an elastic modulus of 0.1-15 GPa. The polymer layer is formed by cross-linking and polymerizing at least one polymerizable monomer containing ether bonds with at least one cross-linking agent. The preparation process is simple and mature, showing great promise for industrialization. It solves the problems of interface instability and slow ion transport kinetics in existing technologies, meeting the operating requirements under low external pressure conditions, enabling all-solid-state batteries to possess both high specific energy and long cycle life.

The application discloses a method for precisely modulating microstructure of a silicon-rich silicon oxide film and a product prepared by the method. x The method comprises the following step S20: in-situ heating SiO x Film samples, and the electron beam generated by the transmission electron microscope is irradiated on the SiO x Film samples, so as to realize the thermal annealing treatment of the SiO x Film. The method promotes the process of decomposing the SiO x Film into nanometer silicon crystals and silicon dioxide by means of heating combined with electron beam irradiation, the processing area can be precisely controlled to the nanometer level, rapid thermal annealing is realized, and damage caused by the thermal annealing to the SiO

The present invention relates to particulate silicon and carbon-based composite particles wherein the particles have a median volume weighted diameter D50 of 0.05 to 10 m, comprising bulk agglomerates having a total amount of Si of 60 to 95 at% and a total content of C of 5 to 540 at%, and wherein the bulk mass further comprises one or more internal shell-like spatial regions having an increased carbon content wherein the elemental ratio of carbon to silicon has a peak in the range of 1 to 15 atomic percentage higher than the average elemental ratio of the bulk material.

This invention relates to the field of secondary battery technology, specifically to a silicon-carbon composite material, its preparation method, and a lithium-ion battery. The preparation method of the silicon-carbon composite material includes: reacting an organometallic framework ZIF-8 in a saturated metal salt solution and then evaporating and crystallizing it to obtain a metal salt-coated organometallic framework Salt@ZIF-8; pulverizing a silicon-copper alloy precursor and the Salt@ZIF-8 at a mass ratio of 1:0.05-0.7 to obtain a mixed powder; and subjecting the mixed powder to a pyrolysis reaction and acid leaching treatment to obtain the silicon-carbon composite material. The silicon-carbon composite material obtained by this invention exhibits excellent structural stability and electrochemical performance, effectively mitigating the volume expansion of the silicon anode and improving cycle performance and rate performance.

The present application relates to a multi-control variable control method of a polycrystalline silicon reduction furnace based on a positive mechanism model, comprising the following steps: S1, collecting and calculating the reaction state, i.e. the real-time deposition rate and the heat loss rate of the reaction; S2, inferring the control parameters: determining the control parameters in the PID control process based on the difference between the real-time deposition rate curve and the target deposition rate curve, wherein the real-time deposition rate curve is generated based on the real-time deposition rate of the reaction progress sequence, and the target deposition rate curve is a preset curve; S3, performing the PID control process: using the control parameters in step S2 to perform PID control on the hydrogen input and the reaction current; the present method determines the optimal deposition rate curve through data analysis, and calculates the deposition rate in real time during the control process. The current heat proportion in the furnace is calculated by using the thermodynamic formula, and the hydrogen and the current are precisely regulated and controlled by combining the proportion with the deposition rate difference, which significantly improves the stability and accuracy of the production process.

The present disclosure relates to the technical field of batteries, and in particular, to a porous carbon material, a silicon-carbon composite material, and use thereof. The porous carbon material of the present disclosure has a microporosity ϕ, a pore volume Pv, and a compressive strength Cs that satisfy the relationship: 550 ≤ (Cs·ϕ) / Pv ≤ 1050, wherein the microporosity ϕ is > 95%, and the compressive strength Cs is 600-850 MPa. The porous carbon material of the present disclosure has a high microporosity, and the microporosity ϕ, pore volume Pv, and compressive strength Cs of the porous carbon material satisfy the relationship: 550 ≤ (Cs·ϕ) / Pv ≤ 1050. This can effectively reduce the particle size of silicon particles, and decrease the absolute expansion size of silicon within the carbon matrix, thereby improving the initial coulombic efficiency and cycling stability of the silicon-carbon composite material.

This application provides a negative electrode material and a preparation method thereof, a secondary battery, and a power-consuming device. The negative electrode material in this application is of a core-shell structure including an inner core and an outer shell. The inner core is a negative electrode active material. The outer shell includes a first shell layer coating a surface of the inner core and a second shell layer coating a surface of the first shell layer, the first shell layer is a transition metal compound layer, the second shell layer is a conducting layer, a maximum thickness of the first shell layer is less than or equal to 10 nm, and the second shell layer is a carbon layer. A total thickness of the outer shell is less than or equal to 15 nm. Based on the negative electrode material, structural stability of the negative electrode material can be improved, a probability of cracking of a coating layer can be reduced, and high energy density of the negative electrode material can be maintained.

The present disclosure relates to a negative electrode active material, a method of manufacturing the negative electrode active material, and a negative electrode including the negative electrode active material. The negative electrode active material comprises a core formed by agglomerated first silicon particles; a shell formed by agglomerated second silicon particles; and an amorphous carbon coating layer surrounding the first silicon particles and the second silicon particles, wherein the shell is disposed on the core, and wherein an average particle diameter (D50) of the first silicon particles is greater than an average particle diameter (D50) of the second silicon particles, the average particle diameter (D50) of the first silicon particles being about 100 nm to about 140 nm, and the average particle diameter (D50) of the second silicon particles being about 40 nm to about 100 nm.

The present application relates to graphene material and its preparation technology, specifically to a method for growing graphene on the surface of non-metallic particles on a large scale, which is suitable for large-scale preparation of graphene-coated non-metallic powder material. The present application uses a two-step method to grow graphene uniformly on the surface of a large number of non-metallic particles: first, mix a large number of non-metallic particles with a carbon source, and form a bulk composite material of non-metallic particles and carbon through low-temperature carbonization; then, pass current to the above bulk composite material using electrodes to heat it to a higher temperature, convert the carbon into graphene, until graphene-coated non-metallic particles are obtained, which are separated from each other, and the high-temperature heating process stops spontaneously. The present application can grow a graphene layer on the surface of a large number of non-metallic particles, the method is easy to scale up, and has the characteristics of good uniformity of graphene coating and high particle separation degree; at the same time, by taking advantage of the large resistance of graphene-coated non-metallic particles which are separated from each other, the high-temperature heating process stops spontaneously.

The invention discloses a preparation process of graphene oxide liquid phase coated nano silicon. The preparation process comprises the following steps: S1, preparing modified nano silicon; s2, preparing a graphene oxide dispersion liquid; step S3: construction of a pre-coating system; s4, carrying out dynamic liquid phase coating reaction; step S5, post-treatment and purification; nano silicon is modified before coating, amino active groups are introduced to the surface of the nano silicon through gamma-aminopropyltriethoxysilane and can interact with carboxyl and hydroxyl on the surface of graphene oxide, the interfacial compatibility of the nano silicon and the graphene oxide is remarkably improved, and the binding force between a coating layer and the nano silicon is enhanced; the falling of the coating layer in the charging and discharging process is effectively inhibited; according to the preparation method, the graphene oxide is prepared by adopting an improved Hummers method, the dispersing agent is added, a stirring-ultrasonic dispersion process is combined, and meanwhile, the temperature in the ultrasonic process is controlled, so that the dispersity of the graphene oxide is effectively improved, agglomeration of the graphene oxide is avoided, and a foundation is laid for subsequent uniform coating.

The invention relates to a particulate material and processes for the preparation thereof. The particulate material consists of a plurality of composite particles. The composite particles comprise a porous particle framework comprising micropores and / or mesopores. The total pore volume of micropores and mesopores as measured by gas adsorption is in the range from 0.4 to 2.2 cm3 / g. The composite particles comprise a plurality of electroactive material domains and a plurality of modifier material domains disposed within the internal pore volume of the porous particle framework. At least a portion of the modifier material domains are located between adjacent electroactive material domains.

The application discloses a negative electrode material and a preparation method thereof, a battery and an electric device. The negative electrode material comprises porous carbon, iron elements and / or sulfur elements are included in the porous carbon, and active materials are included in the pores of the porous carbon. In this way, the negative electrode material has good conductivity, small volume expansion and high surface activity, so that the battery has high capacity, excellent rate performance and cycle performance.

The invention relates to the technical field of lithium ion battery negative electrode materials, in particular to petroleum coke-based porous carbon and a preparation method of a silicon-carbon negative electrode material of the petroleum coke-based porous carbon. The method comprises the following steps: firstly, preparing petroleum coke-based porous carbon with high specific surface area and low ash content through pretreatment, mixed acid deliming, high-temperature carbonization, alkali activation and / or water vapor path activation processes; the silicon-carbon negative electrode material with tight silicon-carbon combination and excellent cycle stability is prepared by taking the porous carbon as a carrier through the steps of gradient-concentration silicon-carbon primary deposition, secondary carbon source deposition densification and post-treatment, so that the problems of high ash content, difficulty in pore regulation, non-uniform silicon-carbon deposition, large volume expansion and the like of the traditional petroleum coke-based material are solved; the raw material source is wide, the process is controllable, environmental benefits and industrialization value are achieved, and the product can be applied to high-energy-density lithium ion batteries.

The invention provides a manufacturing method of a negative electrode material, the negative electrode material, a negative electrode and a lithium ion battery, and the method comprises the following steps: adding a metal salt compound into a first solvent to form a first mixture; adding a silicon-based material into the first mixture to form a second mixture; performing first heat treatment on the second mixture to obtain an intermediate product; adding a carbon-based material and the intermediate product into a second solvent to form a third mixture; and performing a second heat treatment on the third mixture to obtain the negative electrode material, in which the negative electrode material comprises a metal silicide and a carbon coating layer coating the metal silicide, and both the metal silicide and the carbon coating layer are formed during the second heat treatment.