7331results about "Carbon preparation/purification" patented technology

The invention discloses a silicon-carbon negative electrode material, porous carbon and a preparation method, the porous carbon is prepared by mixing ammonium fluoride and a pre-carbonized material to prepare a premix; and putting the premix in an inert atmosphere, and carrying out pre-activation, drying, carbonization, activation and crushing treatment to obtain the composite material. And uniformly depositing the nano silicon particles into the porous carbon skeleton through a mature CVD (Chemical Vapor Deposition) process to obtain the silicon-carbon composite material. Fluorine and nitrogen co-doping modification can increase the defect degree of a carbon skeleton, efficiently relieve mechanical stress accompanied by lithium storage volume expansion of the silicon negative electrode in a micro scale, provide abundant lithium ion transport and mass transfer channels and enhance the conductivity of porous carbon, and ammonium fluoride is used as a supplementary activator besides water vapor, so that the porosity of the porous carbon is further improved, and the conductivity of the porous carbon is improved. An effective space is provided for uniform deposition of silicon, the fluorine-containing carbon layer can induce formation of a high-stability SEI film rich in LiF on the surface of the nano silicon material, and the interface stability and coulombic efficiency of the silicon negative electrode are further improved.

The invention discloses an asphalt-based hard carbon material as well as a pre-oxidation preparation method and application thereof. Belongs to the technical field of asphalt-based hard carbon materials. The pre-oxidation preparation method comprises the following steps: carrying out primary pre-oxidation treatment on asphalt at 250-400 DEG C in air flow of 50-500mL / min; crushing the obtained primary pre-oxidized asphalt, and then carrying out secondary pre-oxidation treatment at 250-400 DEG C in air flow of 50-500mL / min to obtain secondary pre-oxidized asphalt; and carrying out carbonization treatment on the secondary pre-oxidized asphalt. According to the method, the asphalt can be kept in a solid-phase state to be subjected to efficient and thorough oxidation cross-linking reaction, the production cost is reduced, the obtained asphalt-based hard carbon material has high first coulombic efficiency and high capacity, and powerful support is provided for commercial application of sodium-ion battery negative electrode materials and rapid development of an energy storage technology.

The invention discloses a zinc-iodine battery positive electrode material based on corn straw shell derived porous carbon and a preparation method of the zinc-iodine battery positive electrode material. According to the material, corn straw shells serve as the sole carbon source, an indigenous nitrogen-doped biomass charcoal carrier with a hierarchical pore structure is prepared through pre-carbonization and KOH activation processes, and the material is characterized in that the specific surface area is larger than or equal to 1500 m < 2 > / g, and the micropore proportion is larger than 90%. The iodine is loaded on the carrier (the iodine content is greater than or equal to 45wt%) through a vacuum sublimation method to form the indigenous nitrogen-doped biomass charcoal / iodine composite material. According to the positive electrode material, through the synergistic effect of physical confinement and pyridine nitrogen chemical adsorption, the multi-iodide shuttle effect is effectively inhibited, so that the capacity retention rate of the zinc-iodine battery is greater than or equal to 93% after 40000 cycles under the current density of 2A g <-1 >, and the capacity retention rate is greater than 45% under the rate of 10A / g. The method has double benefits of agricultural waste resource utilization and high-performance energy storage device development.

The invention provides a doped electrode material based on porous silicon carbon and a preparation method thereof.The preparation method comprises the steps that a resin base material is smashed and then put into a high-temperature furnace to be subjected to a carbonization process, the carbonization temperature ranges from 300 DEG C to 1500 DEG C, an alkaline additive, a phosphorus source material and a nitrogen source material are sequentially added in the temperature interval, and phosphorus-nitrogen co-doped porous carbon is obtained; the preparation method comprises the following steps: mixing a silicon dioxide microsphere template into phosphorus-nitrogen co-doped porous carbon, adding a first coating carbon source to carry out first coating treatment, and etching the silicon dioxide microsphere template by using an etching solution to obtain a prefabricated object with a cavity structure; and putting the prefabricated object with the cavity structure into a fluidized bed reactor, introducing silicon source gas and a surface activation auxiliary agent, carrying out deposition at 400-550 DEG C, and then adding a second coating carbon source to carry out secondary coating treatment, thereby obtaining the doped electrode material based on porous silicon carbon. Therefore, the expansion coefficient of the electrode material is effectively reduced, and the rate capability is improved.

The invention discloses a preparation method of a composite high-entropy hard carbon negative electrode material and a sodium ion battery, and relates to the technical field of electrochemical energy storage materials. Existing doping limit is broken through through'high entropy design ', atomic-scale mixing of five elements and more than five elements is realized, strong structural stability which cannot be realized by traditional binary / ternary doping is achieved, 'molecular anchoring' and'entropy locking 'are completed by combining a pre-assembly technology with stepped carbonization, the problem of pain point of multi-element segregation is solved, and the method is suitable for large-scale industrial production. Sodium storage dynamic and thermodynamic properties of a high-entropy hard carbon precursor and an intermediate are synchronously improved through elaborate combination design of multiple elements and subsequent carbonization process parameter optimization, 'defect-interlayer spacing-pore structure 'triple regulation is realized, and the defect degree of high-entropy hard carbon is reduced through design of a coating process; the prepared composite high-entropy hard carbon negative electrode material shows excellent comprehensive performance in a sodium-ion battery, and especially has obvious advantages in high initial coulombic efficiency, high rate capability and long stability.

The invention discloses a biomass asphalt composite derivative hard carbon material and a preparation method and application thereof, and the preparation method comprises the following steps: step (1), placing biomass raw material powder in an acid pickling solvent for acid pickling, washing to be neutral after acid pickling, and drying to obtain a biomass precursor; (2) mixing the biomass precursor with asphalt to obtain a precursor mixture; and (3) carrying out low-temperature pre-oxidation on the precursor mixture, and then carrying out high-temperature carbonization, so as to obtain the biomass asphalt composite derivative hard carbon material after the high-temperature carbonization is finished. The prepared biomass asphalt composite derivative hard carbon material is used for preparing a sodium ion battery negative electrode. The technical problems that an existing biomass hard carbon material is low in capacity and tap density, difficult in impurity removal and the like can be solved, the biomass hard carbon material can be used for a sodium-ion battery negative electrode, and the sodium storage performance of a sodium-ion battery is improved.

The embodiment of the invention provides a preparation method of a negative electrode active material, the negative electrode active material, a battery and equipment. Fluorine-containing gas is used as discharge gas, and discharge current is introduced into a plasma treatment device in the process of performing vibration dispersion treatment on a porous carbon substrate through the plasma treatment device; the fluorine-containing gas is used for carrying out plasma discharge treatment on the porous carbon matrix, so that the fluorine element provided by the fluorine-containing gas can react with carbon atoms on the surface of the porous carbon matrix to form chemical bonding, and the chemical bonding uniformity between the fluorine element and the carbon atoms on the surface of the porous carbon matrix can be improved; and the preparation cost of the negative electrode active material can be reduced, and the preparation efficiency of the negative electrode active material is improved, so that the battery capacity and the cycle performance of a secondary battery prepared from the negative electrode active material disclosed by the embodiment of the invention can be improved.

The invention belongs to the technical field of fuel cell electrode material preparation, and particularly relates to a carbon electrode material for a polypyrrole modified bio-based fuel cell and a preparation method of the carbon electrode material. Comprising the following steps: modifying rice hull low-temperature carbonized powder by sequentially adopting POSS (Polyhedral Oligomeric Silsesquioxane) containing unipolar functional groups and POSS containing polypolar functional groups to obtain modified low-temperature carbonized powder; and carrying out in-situ polymerization on a pyrrole monomer on the surface of the modified low-temperature carbonized powder, and carrying out high-temperature carbonization and hydrofluoric acid corrosion to obtain the polypyrrole modified bio-based fuel cell carbon electrode material. The polypolar functional group POSS not only is beneficial to the in-situ polymerization reaction of pyrrole, but also can form a continuous macromolecular chain, and a net structure is formed on the surface of the whole material. The effect of the unipolar functional group POSS is to improve the stability of the low-temperature carbonized powder in the high-temperature carbonization process, and more importantly, the unipolar functional group POSS is to provide a channel for subsequent hydrofluoric acid corrosion, etch away non-conductive substances and improve the conductivity and specific surface area of the carbon electrode material.

A silicon-carbon material, a preparation method therefor, a secondary battery, and an electric device. The silicon-carbon material comprises silicon-carbon composite particles; the silicon-carbon composite particles comprise a porous carbon material, nano-silicon grains and a silicon carbide material layer; the porous carbon material is provided with through pores, the nano-silicon grains are located in the through pores, and the silicon carbide material layer is partially located on through pore walls; the grain size of the nano-silicon grains is not smaller than the average pore diameter of the porous carbon material. The silicon-carbon material is used as an active material of a negative electrode sheet, thereby improving the cycle performance of batteries.

Large-particle, low-specific-surface-area and high-dynamics lithium iron phosphate particles. The primary average particle size of the lithium iron phosphate particles is 500-3000 nm, and the BET specific surface area thereof is 3 m2 / g to 8 m2 / g. By means of calculation on the basis of the total weight of the lithium iron phosphate particles, the carbon content of the lithium iron phosphate particles is Cx weight%, where 0.8≤Cx≤2.0.

According to the invention, biomass rice hull ash and a sodium hydroxide solution are reacted to obtain water glass and carbon mud. And reacting the water glass with CO2 generated by calcining the limestone to produce a white carbon black product and a mixed waste liquid of sodium carbonate and sodium bicarbonate. Meanwhile, quick lime obtained by calcining limestone is digested and then reacts with sodium carbonate and sodium bicarbonate mixed waste liquid to generate a light calcium carbonate product and dilute sodium hydroxide waste liquid. And finally, the dilute sodium hydroxide waste liquid is concentrated and reused for water glass production, so that the waste liquid is recycled, and a complete process closed loop is formed. According to the process method disclosed by the invention, two leading-edge innovative processes, namely production of white carbon black by renewable resource biomass rice hull ash and production of white carbon black by a carbonization method, are organically combined and are coupled with production of light calcium carbonate by a limestone calcination process, so that the problem that a large amount of sodium sulfate-containing wastewater is discharged in a traditional process is solved; meanwhile, the carbon footprint of white carbon black and calcium carbonate products is greatly reduced.

The invention relates to the field of batteries, in particular to a preparation method and system of a silicon-carbon material, and the preparation method comprises the following steps: pretreating porous carbon, conveying the pretreated porous carbon to a fluidized bed reactor, sequentially introducing a silicon source gas and a carrier gas for silicon deposition treatment, heating, introducing a carbon source gas, adjusting the flow of the carrier gas for carbon coating treatment, and discharging and cooling to obtain a finished product, meanwhile, reaction tail gas is recycled. The preparation system comprises a gas inlet unit, a fluidized bed reactor unit, a tail gas circulation unit, a feeding preheating unit and a discharging unit. The fluidized bed reactor comprises an outer shell, an up-down stirring device, a heat exchange assembly and an air distribution assembly, and efficient reaction and temperature control can be achieved. The silicon-carbon material prepared by the method has excellent electrochemical performance and is suitable for a lithium ion battery negative electrode material. The unique porous structure and the uniform carbon coating layer effectively improve the conductivity and the structural stability of the material, and meanwhile, the volume expansion effect of silicon in the charging and discharging process is reduced.

The invention provides a method for preparing a high-performance lithium manganese iron phosphate positive electrode material based on a manganese iron phosphate precursor, and relates to the technical field of batteries. A method for preparing a high-performance lithium manganese iron phosphate positive electrode material based on a manganese iron phosphate precursor comprises the following steps: S1, mixing a phosphorus source, an iron source and a manganese source in a water medium, adding a surfactant, and carrying out ball milling, drying and sintering to obtain the manganese iron phosphate precursor; and S2, mixing the manganese iron phosphate precursor, a lithium source, a carbon source, a doping agent, an auxiliary agent and deionized water, and carrying out ball milling, drying and sintering to obtain the lithium manganese iron phosphate positive electrode material. The method can improve the surface / interface stability while improving the surface conductivity of the material, thereby prolonging the cycle life of the battery and improving the charge-discharge capacity of the battery.

The invention relates to a sodium ion battery, and belongs to sodium ion batteries. The battery cell of the sodium-ion battery comprises a positive plate, a negative plate and an electrolyte, the active material of the positive plate is carbon-coated aluminum-doped sodium ferric sulfate; the chemical formula of the aluminum-doped sodium ferric sulfate is Na < 2 + 2y > Fe < 2-x-y > Al < x > (SO4) 3, x is more than or equal to 0.01 and less than or equal to 0.05, and y is more than or equal to 0.1 and less than or equal to The particle size of the carbon-coated aluminum-doped sodium ferric sulfate ranges from 50 nm to 100 nm; the weight ratio of a carbon coating layer in the carbon-coated aluminum-doped sodium ferric sulfate is 1%-5%; the active material of the negative plate is carbon-coated sodium titanate; the specific surface area of the carbon-coated sodium titanate is 20 m < 2 > / g to 25 m < 2 > / g; the weight ratio of a carbon coating layer in the carbon-coated sodium titanate is 0.5%-3%. Volume expansion is jointly inhibited through structural stability of positive and negative electrode materials, and the cycle life is prolonged.

The invention discloses a method for preparing a supercapacitor electrode through high-temperature alkali activation. The method comprises the steps of preparing porous carbon, preparing an electrode plate, preparing a supercapacitor, and carrying out electrochemical performance testing and material characterization testing. When the carbon precursor of the supercapacitor electrode material is prepared, organic components in walnut shells can be refined and removed and biochar is left by utilizing the effect of removing organic matters in biomass at high temperature of a tubular furnace; the potassium hydroxide with different concentrations is used as the activating agent to activate the biochar, the porosity and the internal structure richness of the porous carbon can be greatly improved, and compared with traditional solid alkali activation, the aqueous solution alkali activation has the advantages that the reliability and the possibility are improved, and the contact area of the activating agent and substances is increased. The electrode material prepared by the method has the advantages of low manufacturing cost, small environmental pollution and excellent service life, and is an ideal electrode material.

The invention discloses a hollow spherical assembly polymer, a carbon material and a preparation method and application of the hollow spherical assembly polymer and the carbon material, and belongs to the technical field of materials. The hollow spherical assembly polymer comprises a shell formed by assembling a plurality of small monomers and a cavity defined by the shell; the small monomers are polymer blocks with morning glory-shaped or spherical crown-shaped structures. By constructing an oil-in-water microemulsion template and adjusting the interaction type of a surfactant and a polymer precursor, a hollow spherical assembly material with various sizes and morphologies assembled by different monomers is controllably synthesized, so that the hollow spherical assembly material meets the application requirements of different fields, and the limitations of tedious steps, difficulty in morphology regulation and control and the like in the prior art are solved; meanwhile, one-pot synthesis is adopted in the method, secondary template removal is not needed, preparation is simple, and the prepared hollow spherical assembly polymer material and the hollow carbon material obtained by directly roasting the material have potential application in the fields of catalysis, biomedicine and the like.

The invention relates to the technical field of mesoporous carbon material preparation, in particular to a high-temperature mesoporous carbon preparation method which comprises the following steps: S1, mixing a metal halide and an inorganic hydrogen bond donor, and heating and stirring until a solution is clear to obtain an inorganic eutectic solvent; s2, mixing the inorganic eutectic solvent and a biomass raw material for reaction; s3, filtering and washing the material obtained in the step S2; and S4, carbonizing the material obtained in the step S3 in a high-temperature inert atmosphere to obtain the high-temperature mesoporous carbon. According to the method, the wood fiber biomass such as the lowest-value straw, the lowest-value bamboo and the lowest-value wood dust is directly used as raw materials, component separation does not need to be conducted on the wood fiber biomass, and high-value utilization of a large amount of low-value wood fiber biomass can be achieved. The method is relatively simple in process, relatively mild in condition and relatively high in product yield, and an activating agent does not need to be used. The biomass mesoporous carbon prepared by the method also has a high specific surface area in a huge mesoporous volume state, and the specific capacitance in an alkaline electrolyte exceeds 260F / g.

The invention relates to the technical field of environmental restoration, in particular to a slow-release material for synergistically restoring heavy metal and organic compound contaminated soil based on modified biochar and microorganisms and an application method thereof.The slow-release material is prepared from, by weight, 50-80 parts of modified biochar, 30-40 parts of sodium alginate, 10-20 parts of gelatin, 5-10 parts of glycerin and 3-5 parts of calcium carbonate. The multi-modified biochar is prepared from, by weight, 300-400 parts of a functional flora mixed solution and 5-10 parts of mixed nutrient elements of glucose, yeast extract and KHPO, and through the synergistic effect of the multi-modified biochar and the functional flora, efficient immobilization (the immobilization rate gt is 60%) of heavy metal (lead, cadmium and chromium) and efficient degradation (the degradation rate gt is 70%) of organic pollutants (polycyclic aromatic hydrocarbon and petroleum hydrocarbon) are achieved.

The invention relates to a phenolic resin modified carbon molecular sieve and a preparation method and application thereof, and belongs to the technical field of adsorbents. The technical problem to be solved by the invention is to provide the phenolic resin modified carbon molecular sieve, and the adsorption selectivity is improved. The method comprises the following steps: a, in-situ polymerization: mixing phenolic resin polymerization mother liquor with a carbon molecular sieve, standing for adsorption, and heating the adsorbed carbon molecular sieve for polymerization reaction to obtain a polymerization product; the phenolic resin polymerization mother liquor comprises a phenolic substance, an aldehyde substance and a solvent; and b, carbonization modification: roasting the polymerization product in a protective atmosphere to obtain the phenolic resin modified carbon molecular sieve. The carbon molecular sieve is modified through phenolic resin in-situ polymerization, and the method is simple, low in cost, high in reaction controllability and suitable for industrial production. The phenolic resin modified carbon molecular sieve has selective adsorbability, can be applied to an N2 / CH4 system, selectively adsorbs N2, and is high in separation ratio and good in stability.

The invention belongs to the technical field of sodium-ion batteries, and particularly relates to a preparation method of a coal-based hard carbon material and application of the coal-based hard carbon material in a sodium-ion battery negative electrode. The preparation method of the hard carbon material comprises the following steps: carrying out acid-base chemical heat treatment on a coal-based material to obtain an ash-removed and dried precursor material, and activating the material by water vapor to obtain a target sample with etched micropore inner gaps, and in the subsequent carbonization process, the carbon layer is twisted to form a closed pore structure to obtain the electrode material. According to the invention, the application of the rich-resource coal precursor and the high carbon conversion rate in the sodium ion battery is realized, and the storage capacity of sodium and the cycling stability of the material are effectively improved. The coal-based hard carbon material can be used for preparing a sodium ion battery and has important application value.

The invention provides a composite sodium ferric phosphate positive electrode material, a precursor and a preparation method thereof, and a sodium ion battery, and belongs to the technical field of inorganic material preparation. Amorphous iron hydrogen phosphate is successfully prepared by innovatively adopting a wet chemical method, the amorphous iron hydrogen phosphate precursor is mixed with the sodium salt, the phosphorus source and the carbon source, the composite sodium iron phosphate positive electrode material is prepared through a solid-phase sintering process, and the prepared composite sodium iron phosphate positive electrode material is high in purity, high in compaction density and good in stability. The structure stability is good, and the specific discharge capacity and the rate capability are excellent; by adopting the positive electrode material, the reversible specific capacity and the service life of the sodium-ion battery can be effectively improved, and high-quality sodium-ion battery supply is provided for the field of energy storage.

The present application discloses a method for recycling and preparing lithium iron phosphate from waste lithium iron phosphate batteries, which comprises the following steps: oxidizing and acid-leaching the recycled lithium iron phosphate battery powder to obtain acid-leached lithium solution and iron-phosphorus filter residue; adjusting the pH of the acid-leached lithium solution for purification and concentration, adding a phosphorus source and adjusting the pH to 9.5 - 10.5 to obtain solution A; subjecting the iron-phosphorus filter residue to secondary acid-leaching, iron dissolution, adding a phosphorus source and adjusting the pH to 6.5 - 7.5 to obtain solution B; mixing solution A and solution B for coprecipitation reaction, and filtering to obtain lithium iron phosphate precursor and reaction mother liquor; subjecting the lithium iron phosphate precursor to anaerobic drying, mixing with a carbon source and sintering to prepare a carbon-coated lithium iron phosphate cathode material. The method provided by the present application has the advantages of short recycling path, few reaction by-products and environmental friendliness, and can recycle all components of lithium, iron and phosphorus in the waste lithium iron phosphate battery powder. At the same time, the by-product is ammonium sulfate, a high-quality fertilizer raw material, which has great application prospects.

The invention provides a composite lithium manganese iron phosphate positive electrode material and a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing a lithium source, an iron source, a manganese source, a phosphorus source, a fluxing agent, a dispersing agent and a solvent to obtain mixed slurry, spray-drying the mixed slurry, and calcining to obtain a lithium manganese iron phosphate intermediate; and (2) mixing the lithium iron manganese phosphate intermediate, a lithium source, a dispersing agent and a solvent to obtain mixed slurry, performing spray drying on the mixed slurry, and performing calcination treatment to obtain the composite lithium iron manganese phosphate positive electrode material. According to the method, the lithium iron manganese phosphate positive electrode material is prepared in a sectional manner, and the lithium iron manganese phosphate positive electrode material which is compact in structure, good in structural stability, high in grain strength, uniform in particle size distribution and high in compaction density can be prepared by adjusting the adding types of the materials and the adding amount of each section.

The invention relates to a silicon-carbon composite material with a porous structure and a preparation method thereof, and the silicon-carbon composite material with the porous structure comprises an N / P co-doped porous carbon skeleton with micropore, mesopore and macropore channel networks, and amorphous or low-crystalline nanometer silicon particles which are uniformly loaded in the porous carbon skeleton and have the average particle size of 15-40nm, the mass percent of silicon in the composite material is 40-60%, and good interface bonding is formed between silicon and carbon. The preparation method mainly comprises the following steps: firstly, preparing an N / P co-doped porous carbon skeleton through a template method in combination with high-temperature carbonization and N / P source co-pyrolysis; and hydrolyzing an organic silicon source in the carbon skeleton to form silicon dioxide, and performing low-temperature metal thermal in-situ reduction to obtain the nano-silicon loaded composite material. Through a unique porous carbon skeleton design and a precise in-situ composite strategy of nano silicon, the prepared material shows high specific capacity, high initial coulombic efficiency and excellent cycling stability and rate capability when being used as a negative electrode of a lithium ion battery.

The invention provides a Na / P double-site doped phosphoric acid ferric sodium pyrophosphate / carbon positive electrode active material and a preparation method and application of the Na / P double-site doped phosphoric acid ferric sodium pyrophosphate / carbon positive electrode active material. The material comprises a Na / P double-site doped ferric sodium pyrophosphate base material and a carbon coating layer coating the surface of the base material, the general formula of the base material is Na (4-x) MxFe3 (PO4) 2-y (QO4) y (P2O7), 0 lt, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 X is less than or equal to 0.4, 0lt; y < = 0.2; m is at least one of K, Li, Mg, Ca and Sr, and Q is at least one of Si, Ge, B and S; specific elements are introduced to the Na site and the P site to form a synergistic doping structure, so that the crystal structure and charge distribution are regulated and controlled, and the electrochemical performance of the material is further improved; the material disclosed by the invention is simple and convenient to prepare, wide in raw material source, suitable for electrochemical energy storage systems such as sodium ion batteries and the like, and excellent in rate capability and long in cycle life.

The invention belongs to the technical field of sodium ion batteries, and discloses a multi-coal composite sodium battery hard carbon negative electrode material, a preparation method and an application, three coal raw materials with different characteristics are used as a basis, and the hard carbon material with excellent structure and good performance is prepared by using respective component characteristics, pyrolysis characteristics and structural characteristics of the coal raw materials. The whole preparation method is simple, the large-scale production difficulty is low, no high-pollution chemical reagent is used, the reversible specific capacity reaches up to 350mAh / g when the material is used as a sodium-ion battery negative electrode material, and the material shows ultrahigh rate capability.

The invention provides a preparation method and application of a polystyrene resin-based spherical carbonaceous porous material, and belongs to the technical field of new energy materials. The method comprises the following steps: firstly, pre-mixing styrene with a cross-linking agent, a pore-forming agent, an initiator and a surfactant at a first preset temperature, then continuously stirring at a first preset stirring speed at a second preset temperature for a first preset time, and carrying out organic polymerization to prepare a polystyrene-based resin microsphere emulsion; then separating and drying the emulsion to obtain polystyrene-based resin microspheres; then oxidizing for a second preset time at a third preset temperature in an air atmosphere to prepare oxidized polystyrene-based resin microspheres; and finally, oxidizing at a fourth preset temperature for a third preset time to prepare the polystyrene resin-based spherical carbonaceous porous material. The method is simple in process and easy to implement, the preparation cost is effectively reduced while the yield is increased, and the method has wide application value and popularization prospects.

The invention discloses a biomass-based sodium ion battery hard carbon material and a preparation method and application thereof, and the preparation method comprises the following steps: uniformly mixing a biomass raw material, an oxidation pore-forming reagent and water to obtain a precursor dispersion liquid, standing and drying the precursor dispersion liquid to obtain a hard carbon precursor, pre-carbonizing the hard carbon precursor at 650-900 DEG C for 1-5 h, and cooling to room temperature to obtain the biomass-based sodium ion battery hard carbon material. And carrying out acid pickling to remove impurities so as to obtain an oxidation pore-forming activated material, carrying out deep carbonization on the oxidation pore-forming activated material at 1150-1450 DEG C for 1-8 hours, and cooling to room temperature, so as to obtain the biomass-based sodium ion battery hard carbon material. The biomass-based sodium-ion battery hard carbon material obtained by the invention has the advantages of high first-circle charge specific capacity, high first-circle discharge specific capacity, high slope capacity, high first-circle coulombic efficiency and high cycle stability.

The invention relates to a preparation method of a nickel ion doped modified ferric sodium pyrophosphate positive electrode material, and belongs to the technical field of sodium ion battery positive electrode materials. The nickel ion doped modified ferric sodium pyrophosphate positive electrode material is prepared by adopting an integrated process system of liquid phase uniform mixing, spray granulation and precise segmented calcination. According to the process system, atomic-scale uniform doping of nickel ions and a specific microstructure of a precursor are realized through spray drying, and a plurality of inherent key technical problems of low electronic conductivity, low ion diffusion rate, impurity phase generation and the like of an NFPP material are solved together through a synergistic effect with a subsequent calcining process; furthermore, the discharge capacity of the ferric sodium phosphate pyrophosphate composite material at high rate is improved, so that the battery has relatively high cycling stability.

The invention provides coal-based porous carbon for preparing a silicon-carbon negative electrode material as well as a preparation method and application of the coal-based porous carbon, coal-based porous graphite is used as a matrix carbon material, polymer resin is used as a rigid bonding and coating material, heterogeneous elements such as B, N and P are used as doping materials, a carbon nanotube is used as a flexible conductive buffer material, and the materials are dispersed in a solvent to form slurry; through atomization granulation and high-temperature carbonization, heterogeneous element doped resin hard carbon is bridged with carbon nanotubes to construct a three-dimensional rigid-flexible conductive network to cooperatively coat the surface of the porous coal-based graphite, and doped heterogeneous elements are utilized to induce chemical-physical auxiliary activation to perform micro-mesoporous precise regulation and control pore forming on an inner core and a shell. The prepared novel coal-based porous carbon is high in porous framework particle strength and reasonable in pore distribution and has a three-dimensional rigid-flexible conductive network core-shell structure. The invention aims to solve the problems of unreasonable pore distribution of porous carbon, poor matrix strength and the like in the preparation process of a novel vapor deposition silicon-carbon negative electrode material.