364 results about "Silicon particle" patented technology

The invention relates to the technical field of electrochemical energy storage devices, in particular to a silicon-carbon negative electrode material, a negative electrode plate, an electrochemical device and an electronic device, and mainly comprises a core material and a coating material, the core material comprises silicon particles, the coating material comprises a porous carbon material doped with indium particles, and the coating material comprises a porous carbon material doped with indium particles. The average pore size of the coating material ranges from 10 nm to 20 nm, and the porosity of the coating material ranges from 35% to 45%. According to the silicon-carbon negative electrode material provided by the invention, the coating material has the effects of buffering and inhibiting silicon volume expansion, so that pulverization of the silicon-carbon negative electrode material is inhibited, and the problem of volume expansion of a battery is solved.

The invention discloses a porous silicon-carbon composite negative electrode material, a one-step preparation method, a lithium ion battery and application, and belongs to the technical field of lithium ion battery materials, the method comprises the following steps: mixing a silicon source, magnesium powder, a carbon source and a soluble pore forming agent to obtain mixed powder; performing high-energy mechanical ball milling on the mixed powder in an inert atmosphere, and performing acid pickling, high-temperature carbonization treatment, cooling, water washing, suction filtration and drying to obtain the porous silicon-carbon composite negative electrode material; the porous silicon-carbon composite negative electrode material comprises a porous shell formed by amorphous porous carbon and a porous core formed by silicon nanoparticles embedded in the porous shell, the mechanical collision energy generated in the high-energy mechanical ball milling process triggers the low-temperature magnesiothermic reduction reaction between the silicon source and the magnesium powder, the carbon source is attached to the surfaces of silicon particles while the silicon particles are generated, and silicon synthesis, carbon coating and pore forming are synchronously achieved. The silicon-based negative electrode has the advantages of high initial coulombic efficiency, high specific capacity, excellent cycle stability and rate capability, and effectively solves the problems of volume expansion and large-scale preparation of the silicon-based negative electrode.

The invention relates to the technical field of batteries, in particular to a silicon-carbon negative electrode material and a lithium ion secondary battery. The silicon-carbon negative electrode material comprises silicon-carbon particles, the silicon-carbon particles comprise a matrix, and the matrix comprises a porous carbon matrix and silicon particles located in internal holes of the porous carbon matrix; the porous carbon substrate is provided with open pores and closed pores, the open pores contain silicon particles, the closed pores contain an element K, and based on the total mass of the silicon carbon particles, the mass content of the element K is 50 ppm to 1000 ppm; the silicon-carbon particles comprise halogen, and based on the total mass of the silicon-carbon particles, the mass content of the halogen is 50 ppm to 2000 ppm; the silicon carbon particles and deionized water are mixed according to the mass ratio of 1: 10 to obtain an aqueous solution, the pH value of the aqueous solution at 25 DEG C is pH 1, and the pH 1 is 6-8. Comprising the silicon-carbon negative electrode material disclosed by the invention has the advantages that the expansion rate is improved, and the rate capability and the cycle performance are improved.

The invention discloses a silicon-carbon composite negative electrode material and a preparation method and application thereof, the silicon-carbon composite negative electrode material comprises porous carbon and silicon particles attached to the porous carbon, and an attachment method between the porous carbon and the silicon particles comprises chemical bond attachment. The lithium battery prepared from the silicon-carbon composite negative electrode material disclosed by the invention has excellent first effect, specific capacity and cycle capacity retention rate. And the preparation method of the silicon-carbon composite negative electrode material has the characteristics of one-step double effects, greenness and high efficiency. Besides, the plasma technology is utilized to excite the medium gas, the two key steps of pore forming and functionalization are completed in one step through the synergistic effect of different medium gases, compared with a traditional chemical activation method, use of strong acid and strong base and the tedious cleaning process are avoided, no waste water is discharged, and the method is more environmentally friendly and saves more energy.

A negative electrode material for secondary battery use includes silicon-containing particles and coating layers covering at least part of the surfaces of the silicon-containing particles. The silicon-containing particles each include an ion conductive phase and silicon phases dispersed in the ion conductive phase. The coating layers contain at least one phosphate compound selected from the group consisting of a phosphate compound, a polyphosphate compound, and a metaphosphate compound, each of which contains an anion represented by general formula (1):In general formula (1), A represents an organic group or an oxygen atom.

The invention discloses a low-cost nano porous silicon-carbon composite material based on a solid waste silicon source as well as a preparation method and application thereof. The preparation method comprises the following steps: taking a solid raw material containing silicon dioxide as a silicon source; carrying out wet ball milling on the pretreated raw materials; mixing the ball-milled material with magnesium powder, aluminum chloride and lithium chloride; carrying out heating reduction reaction on the mixed material; sequentially performing hydrochloric acid pickling and hydrofluoric acid pickling on the reduction product, and then washing to be neutral; mixing the washed silicon particles with a carbon precursor containing nitrogen and sulfur, coating by adopting a spray coating method, and then carrying out carbonization treatment; the carbon precursor containing nitrogen and sulfur is composed of asphalt and thiourea; the carbonization temperature is 750-850 DEG C, the carbonization time is 1-2 hours, and the heating procedure comprises a desolventizing section, an asphalt decomposition section and a carbonization section. The preparation method is low in raw material cost, low in energy consumption, environment-friendly and excellent in product comprehensive performance, and has wide application prospects in the fields of power batteries, energy storage, catalysis and the like.

The invention relates to a uniform carbon-coated mesoporous silicon carbon negative electrode material and a preparation method and application thereof.The preparation method comprises the steps that a product obtained after pyrolysis and carbonization of a biomass carbon source is subjected to alkali activation treatment, acid pickling, drying, smashing, passivation, water washing and drying are conducted to obtain a mesoporous carbon matrix, nanometer silicon particles are deposited in pores of the mesoporous carbon matrix, and the uniform carbon-coated mesoporous silicon carbon negative electrode material is obtained. Then selecting a low-temperature carbonization material and polyethylene glycol to perform pre-carbonization and complete carbonization treatment on the mesoporous silicon carbon material to obtain a carbon coating layer, and finally obtaining the uniform carbon-coated mesoporous silicon carbon negative electrode material. When the uniform carbon-coated mesoporous silicon carbon negative electrode material is applied to a lithium battery, the mesoporous skeleton can effectively inhibit volume expansion of silicon in a battery circulation process, and the uniform carbon-coated layer can effectively reduce the risk of direct contact between the negative electrode material and an electrolyte, so that a stable SE I film is formed to reduce the occurrence of side reactions; and the first coulombic efficiency and the cycle performance of the battery are further improved.

The invention relates to the technical field of battery silicon negative electrodes, in particular to a silicon-carbon composite material and a preparation method and application thereof. The silicon-carbon composite material comprises a three-dimensional through mesoporous carbon skeleton, nano silicon particles loaded in mesopores and a gradient carbon coating layer, nano silicon and the carbon skeleton are connected through Si-O-C covalent bonds, and the gradient carbon coating layer is composed of a soft carbon inner layer, a graphitized carbon middle layer and a compact hard carbon outer layer. The preparation method comprises three steps of synthesis of a three-dimensional through mesoporous carbon skeleton, confinement silicon loading and gradient carbon coating. The material solves the problems of silicon particle agglomeration, volume effect and interface instability, has excellent electrochemical performance, can be used as a lithium ion battery negative electrode material, is suitable for a next-generation high-energy lithium ion battery, and improves the cycling stability and capacity performance of the battery.

The application relates to the technical field of lithium ion batteries, and discloses a silicon-carbon nanotube composite material, which is obtained by dehydration of hydroxylated silicon particles, hydroxylated carbon nanotubes and iminodiacetic acid. The silicon-carbon nanotube composite material provided by the application can anchor the silicon particles on the carbon nanotubes through covalent bond action, can increase the uniformity of dispersion of the carbon nanotubes and the silicon particles, can improve the electron transmission capacity, can play a certain counterforce on the volume expansion force of the silicon particles, can reduce the generation of electrode cracks, can further reduce the consumption of electrolyte, and can improve the cycle stability of the whole electrode. Meanwhile, the preparation method provided by the application does not need a complex operation process, has simple process condition requirements, and is suitable for large-scale production.

A lithium-ion battery component with an electrode includes a current collector and a silicon-based active layer. The active layer includes a polyacrylonitrile lattice structure with continuous carbon domains. Silicon particles are distributed within the vacancies of the polyacrylonitrile lattice, which is configured to confine the silicon particles during the volume expansion and contraction that occurs during charge cycling.

The invention relates to a method for evaluating distribution uniformity of silicon in a CVD (chemical vapor deposition) silicon-carbon composite material. The method comprises the following steps: (S1) acquiring a scanning electron microscope backscattered electron image and a silicon element surface distribution diagram of a sample; (S2) carrying out binarization processing on the silicon element surface distribution diagram through image analysis software, and counting the area proportion sigma Si of the deposited silicon particles; (S3) combining the carbon mass fraction c% of the sample and the correction coefficient delta, and calculating the mass fraction w% of undeposited silicon particles; the correction coefficient delta is obtained through calibration: under the same imaging condition, selecting a region in which all particles are completely covered by a silicon signal and the number of complete particles is not less than 50 from a silicon element surface distribution diagram as a'complete silicon deposition region '; and carrying out the same binarization processing on the silicon particles, wherein the area ratio sigma Si0 of the silicon particles is a correction coefficient delta. The evaluation method provided by the invention has high accuracy, wide applicability and excellent measurement repeatability, and is a scientific and reliable quantitative analysis means.

The present application relates to a kind of carbonized silicon crucible for aluminum alloy smelting and its preparation method.The technical scheme is: carbonized silicon particle A, carbonized silicon particle B, carbonized silicon fine powder A, carbonized silicon fine powder B and xylitol are mixed, immersed in silica sol, dried, heat treated;Silicon dioxide coated carbonized silicon obtained by heat treatment is mixed with alumina powder, vanadium pentoxide and deionized water, to obtain mixed slurry, additional binder, sintering aid, polyacrylamide and gum arabic, mix, ball mill, to obtain carbonized silicon slurry.After exhausting, carbonized silicon slurry is placed in gypsum mold for preparing crucible, stand, pour out excess carbonized silicon slurry, continue to stand, take out the carbonized silicon body after standing, indoor curing, drying, heat treatment at 1300-1500 DEG C, to obtain carbonized silicon crucible for aluminum alloy smelting.The carbonized silicon body prepared by the present application is not easy to break, the sintering temperature of the product is low, the compressive strength is large, the thermal shock stability is high, and the resistance to aluminum alloy melt erosion is strong.

The present invention provides a silicon-carbon composite negative electrode material and a preparation method therefor. The silicon-carbon composite negative electrode material is obtained by depositing silicon-containing particles on pores and surfaces of porous carbon, and then performing surface carbon coating. In an XPS Si 2p spectrum of the silicon-carbon composite negative electrode material, the surface of the material satisfies: 0.4<SSi-Si / SC-Si-O<0.7; and the interior satisfies: 3<SSi-C / SC-Si-O<4. The surface of the material refers to the XPS spectrum measured when the material has not been etched by an argon ion beam, and the interior of the material refers to the XPS spectrum measured after the material has been etched by an argon ion beam to a depth of 70nm. A material having the specified XPS Si 2p spectrum has significantly improved structural strength, capacity and conductivity, thereby improving cycle stability and fast charging performance, and achieving high energy density, for a lithium ion battery assembled using same.

Embodiments of the present application provide a silicon-based composite negative electrode material, a preparation method thereof, a negative electrode sheet and a secondary battery. The preparation method comprises: preparing a precursor fiber by electrospinning a precursor dispersion liquid containing a first silicon source, a second silicon source, a first carbon source and a second carbon source; and obtaining the silicon-based composite negative electrode material by heat treatment of the precursor fiber; the first silicon source is silicon particles; the second silicon source carries one or more of a silicon halogen bond, a silicon oxygen bond and a silicon hydrogen bond in a molecular structure; the first carbon source is a high molecular compound; and the second carbon source is an oxygen-containing small molecule organic compound. The present application adds two silicon sources and oxygen-containing group organic compounds to the spinning precursor dispersion liquid, so as to improve the structural stability and electrochemical performance of the silicon-based negative electrode material, thereby achieving the technical effects of inhibiting volume expansion while ensuring high capacity, significantly improving the cycle stability and safety, and simplifying the preparation process and reducing the cost.

A process for producing composite electrode particles coated with a granular silicon structure, a carbon layer, and zinc oxide, comprising the following steps: introducing several first silicon particles, a macromolecular material, bitumen, and an alcohol solution into a grinding mill for mixing to cause some of the first silicon particles to form several composite silicon particles; then introducing several porous carbon particles into the grinding mill for mixing to form a first mixture; then introducing the first mixture into a rotary evaporator to obtain several mixed powders; then introducing the mixed powders into a sintering furnace to perform atmospheric sintering to obtain several first composite particles coated with the carbon layer that incorporates the first silicon particles and the composite silicon particles;and then the introduction of several zinc oxide particles and the first composite particles into a roller mixer for mixing in order to obtain the composite electrode particles.

This invention belongs to the field of battery active materials technology, specifically disclosing a silicon-oxygen-carbon composite material, its preparation method, and a secondary battery. The silicon-oxygen-carbon composite material is prepared using silicon powder, a carbon source, and an oxygen-generating agent as raw materials via a one-pot, single-step synthesis method, comprising the following processes: heating to a first preset temperature, decomposing the oxygen-generating agent to produce oxygen, oxidizing the silicon on the surface of the silicon particles to form a silicon oxide coating layer, and obtaining Si@SiO. x Particles, 0.5≤x≤2; heated to the second preset temperature, in the Si@SiO x A carbon coating layer is formed on the surface of the particles to obtain the silicon-oxygen-carbon composite material. This invention achieves this by forming a tightly wrapped SiO2 layer on the surface of silicon particles. x The thin film of the silicon layer and the carbon layer effectively buffers the volume expansion of silicon particles during the charging and discharging process, improves the conductivity of the silicon anode, and effectively avoids the side reaction between silicon particles and electrolyte. As an anode material, it exhibits considerable lithium storage capacity and excellent electrochemical performance.

The invention belongs to the technical field of battery materials, and provides a copper net-carbon nanotube-silicon carbon negative electrode plate and a preparation method thereof. The preparation method comprises the following steps: putting a copper mesh and a carbon nanotube into an electrophoretic liquid, and carrying out electrophoretic deposition to obtain a porous copper-carbon nanotube composite precursor; under shielding gas, silane gas is introduced into the porous copper-carbon nanotube composite precursor, vapor deposition is carried out, and a silicon-carbon deposition precursor is obtained; and introducing a carbon source into the silicon-carbon deposition precursor under protective gas, and carrying out carbon coating. The porous interconnection structure of the copper mesh-carbon nanotube composite skeleton is utilized to provide mechanical support and a conductive path, stress is absorbed through pores to avoid stripping of the active layer, and the cycle service life is prolonged; the macroscopic supporting effect of the copper net framework is cooperated with the nanoscale flexible connection of the carbon nanotubes, so that the pulverization of the active silicon particles is inhibited; the copper net provides a longitudinal conductive trunk, and the carbon nanotubes construct transverse conductive branches to form a three-dimensional electron transmission path, so that the charge transfer impedance is reduced.

The invention belongs to the technical field of secondary batteries, particularly relates to a silicon-oxygen-carbon composite negative electrode active material, and further discloses a preparation method of the silicon-oxygen-carbon composite negative electrode active material and application of the silicon-oxygen-carbon composite negative electrode active material to preparation of a battery negative electrode plate and a secondary battery. The silicon-oxygen-carbon composite negative electrode active material comprises a silicon oxide SiOx inner core and a carbon coating layer coating the surface of the silicon oxide SiOx inner core, conductive carbon is dispersed in the silicon oxide SiOx inner core, and a microporous structure is formed in the carbon coating layer. According to the silicon-oxygen-carbon composite negative electrode active material, the conductive carbon is dispersed and mixed in the silicon oxide SiOx particles, the conductive connection effect on the silicon particles is obvious, the defect that the internal conductivity of a silicon-based material is poor is effectively overcome, and the conductivity and expansion performance of the silicon-oxygen-carbon composite negative electrode active material are improved.

The invention discloses a preparation method of a solid-state battery with a silicon-based negative electrode. The preparation method comprises the following steps: preparation of pre-lithiated silicon particles, preparation of a conductive network precursor, preparation of a Si-C composite negative electrode layer, preparation of a composite solid-state electrolyte and battery assembly. Li3PS4 is used as a main electrolyte, LiI and Li3PS4 form a solid solution with low grain boundary impedance, so that the activation energy is reduced from 0.35 eV to 0.28 eV, then Li3N is added as an interface modifier, N3-contained in the Li3N can react with Si-OH on the surface of silicon to form a stable Si-N bond, and the interface impedance is greatly reduced; then CNT is used as an electronic conductive main body, and after the CNT is modified by a coupling agent, amino groups on the surface of the CNT and P in Li3PS4 can form stable C-P bonds, so that Li3PS4 particles are uniformly loaded on the surface of the CNT, and an electron-ion double-conductive channel is formed; and moreover, a lithium naphthalene tetrahydrofuran solution is adopted to carry out mild pre-lithiation on the silicon particles, so that active lithium required by formation of an SEI layer is accurately supplemented, excessive lithium is prevented from reacting with electrolyte, lithium loss is reduced, and the utilization rate of lithium is increased to 90% or above.

The invention discloses a simulation optimization method for preparation parameters of a silicon carbide particle reinforced metal matrix composite, which comprises the following steps: S1, setting the temperatures of a preform and a sand box to be room temperature, and selecting circular ceramic particles for pouring to obtain a casting; s2, after three-dimensional graph drawing is carried out on a casting in Creo, a model is converted into an igs format and then imported into Procast, and then grid division is carried out in the Procast; s3, other variable parameters are kept constant, only the pore size of the ceramic particles is changed, and the optimal pore size is determined through simulation analysis. Accurate guidance is provided for performance improvement and practical application of the ceramic particle reinforced metal matrix composite, scientificity and preciseness of simulation research are ensured, and follow-up experimental verification and practical production and application of the material are powerfully supported.

The invention provides a method for preparing a silicon-carbon negative electrode material by using a waste photovoltaic module, which comprises the following steps of: (1) disassembling and crushing to obtain silicon / silver / aluminum / EVA (Ethylene Vinyl Acetate) mixed powder; (2) carrying out alkali etching to obtain etched silicon / silver / EVA (Ethylene Vinyl Acetate) powder; (3) synergistic carbonization coating: constructing a double-layer carbon coating structure of'inner layer hard carbon-outer layer soft carbon 'on the surface of the silicon particles in situ to obtain a silicon-carbon composite material; (4) carrying out heat-moisture treatment, so that the catalytic active component is stably anchored on the surface of the material, and the transition metal salt is decomposed into metal oxide to obtain a graphite / silicon carbon material; and (5) performing in-situ catalytic growth of a carbon nanotube on the graphite / silicon carbon material to obtain the silicon carbon negative electrode material with a porous silicon-carbon tube-double carbon layer three-dimensional conductive network structure. The silicon-carbon negative electrode material obtained by the invention has high specific capacity, excellent cycle stability and rate capability.

The application discloses a method for preparing high-dispersed nickel-silicon oxide particles on the surface of YSZ particles, and the method comprises the following steps: loading nickel oxide on the surface of YSZ (Ni / YSZ) by using an impregnation method, and coating a uniform and dense amorphous SiO2 film on the surface of the Ni / YSZ particles by using a chemical vapor deposition method; the film is in close contact with the nickel oxide, and after high-temperature calcination at 1400 DEG C, the film becomes spherical small particles and is uniformly dispersed on the YSZ framework. The uniformly distributed nickel-silicon oxide particles on the surface of YSZ prepared by the method can effectively inhibit the agglomeration of Ni in the water and heat cycle of the battery, and can significantly improve the current density.

The application relates to the technical field of preparation of lithium ion battery negative electrode materials, in particular to a graphene-coated silicon-carbon composite material and a preparation method and application thereof. The preparation method of the graphene-coated silicon-carbon composite material comprises the following steps: microwave-assisted sand milling mixing of a nano-silicon dispersion liquid, a pitch dispersion liquid, a three-block copolymer Pluronic F127 and zirconium oxide beads to obtain a mixed solution of pitch silicon particles; microwave-assisted sand milling dispersion of a sulfonated graphene dispersion liquid into the mixed solution of pitch silicon particles to obtain a slurry of sulfonated graphene-coated pitch silicon particles; and drying and heat treatment of the slurry of sulfonated graphene-coated pitch silicon particles to obtain the graphene-coated silicon-carbon composite material. The graphene prepared by the preparation method effectively buffers the volume effect generated in the lithium intercalation and deintercalation process of the silicon-based negative electrode material, so that the electrochemical performance of the material is improved.

Embodiments of the present invention relate to a biomass-derived porous carbon material, a preparation method therefor, and a use thereof. The biomass-derived porous carbon material is composed of graphite-like carbon microcrystallites. The biomass-derived porous carbon material has a degree of ordering η of 20000-80000, an equivalent number of atomic layers ηa of carbon atoms periodically arranged along the a-axis direction is 30-50, and a number of atomic layers ηc of carbon atoms periodically arranged along the c-axis direction is 20-40. In an X-ray diffraction pattern of the biomass-derived porous carbon material, the (002) crystal plane has a diffraction angle 2θ ranging from 24.5° to 26.2°, the graphite-like carbon microcrystallites has a carbon interlayer spacing of 0.340 nm to 0.365 nm, and the (002) crystal-plane diffraction peak has a full width at half maximum β002 of 0.5 rad to1.5 rad. In the present invention, the degree of ordering and the interlayer spacing of carbon atomic layers in the graphite‑like carbon microcrystallites enable the biomass-derived porous carbon material to have sufficient strength and electrical conductivity, so that the material does not undergo mechanical fracture or deformation during repeated charge-discharge processes, thereby effectively suppressing volume expansion of nano-silicon particles, improving the initial coulombic efficiency and rate performance of the battery, and prolonging the cycle life and service life of the battery under high-rate conditions.

The application discloses a preparation method of nitrogen-doped carbon-silicon nanofibers and application of the nitrogen-doped carbon-silicon nanofibers in a lithium ion battery negative electrode material, and belongs to the technical field of lithium ion battery negative electrode materials. The method comprises the following steps: mixing silicon nanoparticles and a carbon source, performing electrostatic spinning, stabilization treatment and carbonization treatment, and obtaining carbon-silicon nanofibers; and then mixing the carbon-silicon nanofibers with a nitrogen source, performing heat treatment under an inert atmosphere, making nitrogen elements doped into a carbon skeleton, and obtaining nitrogen-doped carbon-silicon nanofibers. The material obtained by the application is a one-dimensional nanofiber structure, silicon particles are uniformly wrapped in carbon fibers, and nitrogen elements are uniformly distributed in the carbon skeleton. The method can realize uniform nitrogen doping while maintaining the microstructure of the material, and significantly improves the electronic conductivity and interface stability of the material. The material obtained by the application is used as a lithium ion battery negative electrode, and exhibits high reversible capacity and excellent cycle stability.

The invention provides a negative electrode active material and a preparation method and application thereof. The negative electrode active material comprises silicon particles; the graphite material layer coats at least part of the surfaces of the silicon particles, a metal compound is doped in the graphite material layer, and metal elements in the metal compound comprise one or a combination of at least two of copper, cerium, magnesium, chromium, manganese or nickel; in a plurality of sites of the graphite material layer, the variance of the content of the metal compound in the graphite material layer is less than 2.5 * 10 <-5 >. According to the negative electrode active material as well as the preparation method and the application thereof, expansion of silicon particles can be inhibited, the ion transmission performance of the material can be enhanced, and the cycle and rate performance of a battery can be improved.

The invention relates to the technical field of Pickering emulsion preparation, and discloses a functionalized mesoporous silicon particle, a Pickering emulsion as well as a preparation method and application of the Pickering emulsion. The functionalized meso-porous silicon particles comprise meso-porous silicon particles and silicon dioxide shell layers coating the surfaces of the meso-porous silicon particles; wherein an ultraviolet filtering agent is loaded in the meso-porous silicon particles. The functionalized meso-porous silicon particle provided by the invention not only reduces free radicals generated by photodegradation of an ultraviolet filtering agent by 89.3%, effectively overcomes the contradiction of'protection-damage 'in traditional ultraviolet protection, but also reduces the wettability of the particle from 114.7 degrees to 89.6 degrees, so that the particle has excellent emulsion stability and ultraviolet shielding function, and meanwhile, the functional meso-porous silicon particle can be applied to the field of ultraviolet protection. The secondary silicon layer packaging also reduces the leakage of the ultraviolet filtering agent; when the functionalized meso-porous silicon particle is used as an emulsifier for preparing a Pickering emulsion carrying a photosensitive active matter, a corresponding ultraviolet filtering agent is matched aiming at a sensitive wave band (UVA or UVB) of the photosensitive active matter, so that customized and high-efficiency light protection is realized.

The invention relates to the technical field of water pollution flotation method treatment, and discloses a flotation separation device for separating silicon particles in waste liquid, which comprises a base table, a flotation box is fixedly connected above the base table, a partition plate is fixedly connected at the center of the inner wall of the flotation box, and the flotation box is divided into a treatment bin I and a treatment bin II by the partition plate; a screening bin is fixedly connected to the upper portion of the flotation box, a feeding bin is fixedly connected to the top of the screening bin, a screening assembly is arranged in the screening bin, a drainage assembly is arranged below a screening net plate, the drainage assembly comprises two parallel drainage plates, and the drainage assembly accurately switches a drainage channel to enable the screening net plate to rotate. Fine silicon particles and coarse silicon particles enter the first treatment bin and the second treatment bin respectively, then the fine silicon particles and the coarse silicon particles are separated for flotation separation, appropriate flotation conditions can be provided according to the characteristics of the coarse silicon particles and the fine silicon particles, the flotation effect and the recovery rate of the silicon particles are improved, and therefore silicon particle products more uniform in quality and higher in purity are obtained.

The invention provides a battery monomer and a preparation method thereof, a battery device, a power utilization device and an energy storage device, and belongs to the technical field of batteries. The battery monomer comprises a negative pole piece, the negative pole piece comprises a current collector, a first coating and a second coating, the first coating and the second coating are arranged on the same surface of the current collector, the first coating and the second coating are alternately arranged on the surface of the current collector, and the thickness of the first coating is larger than that of the second coating in the first direction; wherein the first direction is perpendicular to the surface of the current collector, the first coating comprises a graphite material, and the second coating comprises a silicon material. The first coatings and the second coatings are alternately arranged on the same surface of the current collector, and the thickness of the first coatings is larger than that of the second coatings in the first direction, so that stress generated by the second coatings in the cold pressing and charging and discharging processes can be effectively dispersed, the probability that silicon particles in the second coatings are broken is reduced, and the service life of the current collector is prolonged. And the structural stability and the cycle performance of the negative pole piece are improved.

The invention provides a high-strength high-thermal-conductivity reaction-sintered SiC ceramic material and a preparation method thereof.The preparation method comprises the following steps that silicon carbide powder and carbon source powder are mixed and then subjected to ball milling treatment, and mixed powder is obtained; mixing the mixed powder with a binder, a plasticizer and a lubricant, and carrying out high-speed centrifugal stirring and rolling homogenization treatment to obtain a silicon carbide mud blank for injection molding; putting the silicon carbide mud blank for injection molding into a mold, carrying out hot-press injection molding, demolding to obtain a silicon carbide prefabricated body, and carrying out glue removal treatment to obtain a silicon carbide biscuit; and paving silicon particles on the silicon carbide biscuit, carrying out vacuum high-temperature infiltration, and cooling. According to the preparation method, the plastic deformation capacity of the silicon carbide mud blank is optimized by regulating and controlling the component proportion, in the preparation process, the movement rearrangement effect among particles is enhanced by applying reinforced shearing centrifugal stirring and rolling treatment to a mixed system, the density of a biscuit is effectively improved, residual silicon is promoted to be uniformly distributed, and the content and size of the residual silicon are reduced; and the overall performance of the material is improved.