70results about How to "Shorten the diffusion path" patented technology

The invention provides an ultrahigh-nickel single-crystal positive electrode material and a preparation method and application thereof.The ultrahigh-nickel single-crystal positive electrode material comprises fluxing agent doping elements and high-valence doping elements, the fluxing agent doping elements comprise Zr, Ce, Sr, Y, La, Sn or Na, and the high-valence doping elements comprise Sb, W, Nb, Ta, Mo, Ti or P; the doping amount of the fluxing agent doping element is omega A, the doping amount of the high-valence doping element is omega B, and omega A and omega B meet the following relational expression: 0.5 < 0.746 * exp [-omega B / (0.891 * omega A)] + 0.556 < 1.0. Omega A and Omega B meet a specific relational expression, two doping elements are effectively promoted to play a role, a small-particle-size and uniformly-dispersed single crystal is formed, the material has high stability and safety of the single crystal, a Li < + > diffusion path can be shortened, dynamics can be improved, and the advantage of high capacity can be achieved.

The invention discloses a preparation method of a defective graphene negative electrode for a lithium battery, which comprises the following steps: grinding natural graphite into powder, carrying out graphite modification by irradiation of a high-current pulse electron beam, mixing with a conductive agent and a binder to prepare slurry, and coating the slurry on a metal foil to prepare the defective graphene negative electrode for the lithium battery. Natural graphite is modified through high-current pulse electron beam irradiation, obvious expansion deformation occurs on the surface of the natural graphite, defects are generated on a graphite structure, mutual stripping between graphite layers is achieved, the whole surface of the graphite is in a hairy wrinkle form, the structure is almost transparent, and the storage capacity and the cycling stability are obviously improved; the obtained defective graphene negative electrode material provides more channels for lithium ion diffusion, the ion diffusion path is effectively shortened by internal gaps, and a physical method is adopted, a specific reducing agent, an oxidizing agent or other intermediate media do not need to be used, and introduction of impurities is avoided.

The invention discloses a vanadium-doped lithium manganese iron phosphate positive electrode material as well as a preparation method and application thereof. Secondary hydrothermal treatment is adopted, so that the particle size and the size of the material can be obviously controlled, short nanorod particles of lithium manganese iron phosphate grow into nanoparticles with the length smaller than 100 nm and the width smaller than 20 nm in an oriented mode, the diffusion size of Li < + > in the [010] direction is reduced, the diffusion path of Li < + > is shortened, meanwhile, ammonium metavanadate serves as a vanadium source to carry out Fe / Mn site substitution on the lithium manganese iron phosphate positive electrode material, and the lithium manganese iron phosphate positive electrode material is obtained. The preparation method has the advantages of reducing the dissolution behavior of manganese, increasing lattice defects, improving the lattice constant, carrying out double-layer modification of morphology and structure, ensuring the migration rate of Li < + > in the charge-discharge process, and realizing the improvement of the electrochemical performance of the lithium manganese iron phosphate positive electrode material.

The invention discloses a high-entropy ferric pyrophosphate sodium ion battery positive electrode material and a preparation method thereof, and belongs to the field of battery positive electrode materials. The chemical formula of the positive electrode material is Na4Fe3-aMa (PO4) 2P2O7 (0.05 < = a < = 0.5), M is a metal element and comprises at least five of cobalt, magnesium, zirconium, zinc, aluminum, molybdenum, copper, manganese, nickel, calcium and chromium, the high-entropy ferric sodium phosphate pyrophosphate battery positive electrode material is spherical, and the surface of the high-entropy ferric sodium phosphate pyrophosphate battery positive electrode material is coated with an amorphous carbon layer. The preparation method adopts a sol-gel method and comprises the following steps: mixing an iron source, a doped metal source, sodium pyrophosphate, ammonium dihydrogen phosphate and citric acid monohydrate according to a stoichiometric ratio, stirring, gelatinizing and drying to obtain xerogel, and calcining through a two-stage hydrogen-argon mixed gas to obtain the iron-doped metal-doped sodium pyrophosphate / citric acid composite material. The crystal structure is optimized by means of the high-entropy synergistic effect, the electron conductivity and the Na < + > diffusion rate are improved, and the industrial adaptability of the spherical morphology and the structural stability of carbon coating are combined.

This invention belongs to the field of wet electronic chemicals technology, specifically relating to a method for preparing electronic-grade hydrogen peroxide. The method includes the following steps: adjusting the concentration of raw hydrogen peroxide, and then filtering it sequentially through a reverse osmosis membrane, a modified cation exchange resin, an anion exchange resin, and a mixed ion exchange resin to obtain electronic-grade hydrogen peroxide. The modified cation exchange resin used is modified based on conventional cation exchange resin through pore expansion and grafting, optimizing the spatial matching of pore structure and functional sites. This achieves passivation of metal ions, enhanced adsorption capacity, and improved oxidation resistance, as well as a deep synergistic effect of these three effects. Ultimately, it achieves the dual goals of efficient purification and stable operation of the resin in the hydrogen peroxide system. The resulting electronic-grade hydrogen peroxide can reduce the content of single impurity metal ions to below 5 ppt, meeting the requirements of SEMI G5 standards, and can be directly applied to high-end manufacturing fields such as semiconductor wafer cleaning.

This invention belongs to the technical field of lithium battery anode materials, specifically relating to a highly conductive graphite electrode material and its preparation method. The preparation method includes: pre-dissolving sodium carboxymethyl cellulose into a gel solution, then ball-milling and mixing graphite and conductive carbon black, dispersing them together with a cobalt hexacyanorubium(II)-dodecyltungstencobalt(III) salt hybrid material and hafnium diboride nanomaterials in the gel solution, adjusting the acidity, adding styrene-butadiene rubber emulsion to obtain a uniform slurry, and then coating, drying, and compacting to obtain the anode sheet. This invention significantly improves the conductivity and structural stability of the graphite anode through the synergistic effect of the interface modification of the cobalt hexacyanorubium(II)-dodecyltungstencobalt(III) salt hybrid material and the conductive framework of the hafnium diboride nanomaterials. The process is safe and controllable, and suitable for industrial production of lithium-ion batteries.

The present application relates to the technical field of sodium battery materials, in particular to a sodium supplement coating based on a spiral iron-carbon composite material and a preparation method thereof, a spiral polypyrrole template is synthesized by a chiral template method, Fe3C@CNS spiral carbon composite material rich in Fe3C nanocrystals and iron single-atom sites is prepared through iron loading, sulfidation and high-temperature pyrolysis, Na2C2O4@Fe3C@CNS composite material is prepared by highly dispersing sodium oxalate on the surface and in the pores of the spiral carbon composite material through a recrystallization method, finally, a slurry is prepared by mixing the Na2C2O4@Fe3C@CNS composite material with a conductive agent and a binder, and the slurry is coated on the surface of an electrode to form a functional sodium supplement coating. The sodium supplement coating based on the spiral iron-carbon composite material and the preparation method thereof solve the problems of poor interface stability and first-cycle irreversible sodium loss of existing sodium ion batteries, realize efficient sodium pre-activation and interface synergistic regulation, and improve the comprehensive performance of the battery.

The invention relates to the technical field of synthesis of zeolite molecular sieves, in particular to a preparation method of an in-situ metal-loaded hierarchical pore MFI type ZSM-5 zeolite molecular sieve material. The method comprises the following steps: 1, adding a trivalent aluminum source and a hydroxyl ion source into deionized water, and stirring to obtain a clear solution; 2, adding a tetravalent silicon source into the clear solution, stirring, adding a molecular sieve template agent and a boron source, stirring, and adding a metal complex solution to obtain a mixed solution; 3, mixing the mixed solution with commercial sponge in a hydrothermal reaction kettle, and crystallizing through hydrothermal reaction; 4, after crystallization is finished, quenching, filtering, centrifuging, washing and drying the mixture in the reaction kettle to obtain a crystallized product; and 5, calcining the crystallized product. The method has the advantages of simple production process, cheap and easily available raw materials, low energy consumption, high product crystallinity, low production cost and good economic benefit, and is suitable for batch production.

The invention provides a graphene / activated carbon composite material and a preparation method and application thereof, and belongs to the technical field of nano materials, the graphene / activated carbon composite material comprises a carbon matrix and a two-dimensional sheet material covering the carbon matrix; the carbon matrix is an activated carbon material and is a carbon material prepared by performing high-temperature pyrolysis on magnesium citrate in a high-temperature self-propagating reaction process; the two-dimensional sheet material is a graphene material and is a few-layer carbon material which is prepared by converting CO2 through a high-temperature self-propagating reaction and is formed by arranging carbon atoms according to a honeycomb-shaped two-dimensional lattice. According to the invention, graphene is used as a conductive and structural dual skeleton; and a hierarchical pore structure is constructed by utilizing gas production and template effect in the reaction process, so that the electrochemical performance of the active carbon positive electrode is improved. And a proper amount of graphene can provide more active sites and maintain the structural stability at the same time, so that the specific capacity and the cycle life are remarkably improved and prolonged, and the material has a wide application prospect and is particularly suitable for preparing a high-performance lithium ion capacitor positive electrode material.

The invention provides a silane deposition silicon-carbon composite material as well as a preparation method and application thereof, and belongs to the technical field of lithium battery materials. The preparation method comprises the following steps: performing in-situ reaction on zinc salt, dimethylimidazole and a pore-forming agent to obtain a first precursor; and after carbonization treatment, alkali activation is carried out, and then vapor deposition is adopted to obtain the silane deposition silicon-carbon composite material. The prepared silane deposition silicon-carbon composite material has good stability and mechanical strength, hierarchical pore structure distribution and high-capacity ultra-long circulation. The method can solve the problems that existing vapor deposition silicon-carbon is poor in structural stability, and pores of a carbon matrix obtained through traditional ZIF-8 carbonization are prone to collapse.

The invention provides a vanadium-doped Co9S8 nanosheet array as well as a preparation method and application thereof. The invention provides a vanadium-doped Co9S8 nanosheet array preparation method, which comprises: dissolving a cobalt salt and 2-methylimidazole in deionized water, adding foamed nickel, and carrying out a reaction at a room temperature to obtain a Co-ZIF nanosheet array precursor; then adding the VCo-ZIF nanosheets into a sodium metavanadate solution, and carrying out hydrothermal reaction to obtain a VCo-ZIF nanosheet array; and finally, adding the VCo-ZIF into a sulfur source solution, and vulcanizing to obtain the vanadium-doped Co9S8 nanosheet array. The formed porous nanosheet structure can provide a larger active specific surface area, the synergistic effect between Co and V ions can improve the charge storage capacity of the material, and sulfur vacancies on the surface of the electrode material can increase the conductivity and the number of active sites. Practice shows that when the material is used as a supercapacitor electrode material, the specific capacity and the rate capability are remarkably improved.

The application relates to the technical field of battery materials, and discloses a sodium-philic carbon-based material, a negative-electrode-free current collector, a preparation method of the sodium-philic carbon-based material and a sodium metal battery. The preparation method of the sodium-philic carbon-based material comprises the following steps: providing a mixed solution, wherein the mixed solution comprises carbon source powder, an iron source and a solvent; fully reacting the mixed solution in a protective atmosphere at 160-240 DEG C; obtaining a carbon-loaded sodium-philic material after solid-liquid separation; fully calcining the carbon-loaded sodium-philic material in an inert atmosphere at 700-900 DEG C to obtain a porous sodium-philic precursor; and treating the porous sodium-philic precursor in a reaction gas atmosphere at 400-700 DEG C for 1-3 hours to obtain the sodium-philic carbon-based material. The reaction gas atmosphere is an ammonia gas and inert gas mixed atmosphere or an ammonia gas atmosphere. The material is coated on the surface of the negative-electrode-free sodium metal battery current collector, and can enhance the electrochemical performance of the battery.

This invention relates to a core-shell structured sodium iron phosphate pyrophosphate cathode material, its preparation method, electrode sheet, and battery, belonging to the technical field of methods or devices for directly converting chemical energy into electrical energy. The core-shell structured sodium iron phosphate pyrophosphate cathode material of this invention comprises primary particles, each primary particle including: a core, a sodium iron phosphate pyrophosphate shell layer disposed on at least a portion of the surface of the core, and a carbon coating layer located within the pores and on the surface of the sodium iron phosphate pyrophosphate shell layer; the core includes a NASICON-type sodium-ion inorganic solid electrolyte with an average particle size ≤50nm; the average thickness of the sodium iron phosphate pyrophosphate shell layer is ≤500nm; the chemical formula of the sodium iron phosphate pyrophosphate shell layer is Na₄Fe₂O₃. 3‑ x M x (PO4)2P2O7, 0≤x≤0.9, M is a doped metal element. The core-shell structured sodium iron phosphate pyrophosphate cathode material of this invention combines high solid density, high conductivity and good electrochemical performance.

This invention discloses a modified sodium vanadium fluorophosphate material, its preparation method, and its applications. To address the technical problems of low conductivity and poor rate performance in existing sodium vanadium fluorophosphate materials, this invention employs a sodium hexametaphosphate-assisted hydrothermal method to construct an integrated preparation system of "surfactant regulation-hydrothermal crystallization." Sodium hexametaphosphate stabilizes the system and regulates the crystal nucleation rate by coordinating polyphosphate ions with the metal ions of the sodium vanadium fluorophosphate precursor. Simultaneously, it adsorbs at the crystal growth interface, inhibiting particle agglomeration and adjusting the crystal facet growth rate ratio through steric hindrance. The particle size of sodium vanadium fluorophosphate is continuously adjustable by controlling the amount of sodium hexametaphosphate added. The beneficial effects of this invention are: it effectively improves electrode mass transfer efficiency, synergistically enhances the electrochemical performance of sodium vanadium fluorophosphate materials, establishes a simple and efficient "one-step synthesis-performance optimization" technical solution, and provides a theoretical basis and experimental reference for the preparation and application of high-performance sodium vanadium fluorophosphate materials.

The invention discloses a resin-based sodium-ion battery hard carbon material and a preparation method thereof, and relates to the technical field of sodium-ion battery material preparation. The preparation method comprises the following steps: carrying out cross-linking reaction on a mixture of resin and a cellulose-based derivative to obtain a cross-linked precursor, and then carrying out pretreatment and high-temperature carbonization on the precursor to obtain the resin-based sodium-ion battery hard carbon material. The adopted resin and cellulose derivative have the advantages of low cost and wide source, have rich functional groups, and can be used as cross-linking agents to improve the cross-linking degree of the precursor, reduce the specific surface area of the hard carbon material and improve the first coulombic efficiency; carbonate generated in the pretreatment process of the cellulose derivative can be used as a salt template to regulate and control the internal pore structure of hard carbon. The rich pore structure is beneficial to permeation of electrolyte, the diffusion path of sodium ions can be shortened, and active sites of hard carbon are fully utilized, so that the cycling stability and the rate capability of the sodium ion battery are improved.

The invention relates to the technical field of lithium manganese iron phosphate materials, in particular to modified lithium manganese iron phosphate, a preparation method thereof, a positive electrode material, a battery and application. The modified lithium manganese iron phosphate is prepared from the following raw materials: lithium manganese iron phosphate, C7H7ZnCl and silane; the mass ratio of the lithium manganese iron phosphate to the C7H7ZnCl to the silane is 1: (0.01 to 0.06): (0.01 to 0.08). According to the modified lithium manganese iron phosphate provided by the invention, the raw material contains the silane, and the silicon dioxide obtained by sintering the silane is used as a supporting structure of the LFMP, so that the thermal stability of the LFMP is improved.

The invention relates to the technical field of building materials and ocean engineering protection, in particular to a preparation method of a marine concrete heavy anti-corrosion coating. Comprising the following steps: 1, preparing materials and carrying out dry mixing to obtain an inorganic dry powder base material; step 2, preparing and mixing wet materials, taking polymer emulsion, a silane coupling agent and water, and uniformly mixing the polymer emulsion, the silane coupling agent and the water; in a stirring state, slowly dropwise adding the mixed solution into the inorganic dry powder base material in the step 1; step 3, dispersion and defoaming: stirring is kept in the dropwise adding process, a defoaming agent is added, high-speed dispersion is performed until the slurry is in a uniform flow state and has no obvious bubbles, and heavy-duty cement-based composite coating slurry is obtained; 4, film forming construction is conducted, specifically, a concrete base surface is coated with the slurry obtained in the step 3 through a layered coating technology, and an anti-corrosion coating is formed after standing and curing. According to the invention, the physical compactness of the coating is greatly improved, the water absorption rate of the coating is obviously reduced, and the anti-permeability pressure is improved.

The application relates to the field of secondary batteries, in particular to a kind of antimony negative material and its preparation method, lithium ion battery and terminal, organic ligand containing carboxyl and mercapto, antimony source and polyethylene glycol are mixed to obtain solution A; Sodium borohydride and selenium source are added into ethanol, and then polyethyleneimine is added to obtain solution B; Solution A and solution B are mixed to carry out solvothermal reaction; The solvothermal reaction product is collected, washed and dried, and the lithium ion battery assembled by the antimony-based negative material of the application shows excellent electrochemical performance and can be used in various terminals.

The invention relates to a structural battery based on integration of a honeycomb composite material and an electrochemical energy storage unit. According to the structural battery, a force bearing function and an electric energy storage function are combined. According to the battery, a bionic honeycomb composite material is adopted as a matrix, and a lithium ion electrochemical unit is embedded into the matrix, so that the multifunctional structure battery with high mechanical strength and excellent electrochemical performance is formed. The honeycomb composite material is used as a carrier and an ion transmission channel of an electrode active material, and is also used as a bearing structure of a mechanical load. According to the design, the energy density, the safety and the cycle life of the battery are remarkably improved, and the battery is particularly suitable for the fields of electric automobiles, aerospace and the like with relatively high requirements on light weight and space utilization rate.

The invention provides a quick-welding and high-reliability brazing film and a preparation method and a using method thereof, and belongs to the technical field of welding. According to the invention, a Ni / Al self-propagating reaction film is combined with a low-melting-point Sn weld-aid layer by relying on hot-pressing, electro-deposition and anodic oxidation composite process molding, and a multi-layer structure brazing film of a porous energetic film-Ni reaction layer-Sn anchoring layer is designed. According to the method, multi-point laser triggering and gradient pressure synergistic effect are combined, accurate regulation and control of multi-point triggering-reaction-welding can be achieved, the film is subjected to global uniform self-propagating exothermic reaction, rapid brazing connection is achieved, and an alloying connection interface with high bonding strength is formed. The process is simple, convenient and rapid, high in production efficiency and low in cost, the production period can be remarkably shortened, the problems that a traditional film interface is weak in bonding force, prone to layering and falling off and the like are effectively solved, welding faces of any shapes can be adapted, and a new technical approach is provided for efficient connection of complex components.

The invention discloses a room-temperature hydrogen sulfide (H2S) sensor based on stannic oxide (SnO2) hollow spheres and polypyrrole (PPy) nanotubes and a preparation method of the room-temperature hydrogen sulfide (H2S) sensor, and belongs to the technical field of gas sensors. A green and low-cost chemical synthesis process is adopted, SnO2 hollow spheres and PPy nanotubes are prepared, a gas sensitive material with a multi-stage micro-nano structure and a p-n heterojunction is formed through composite construction, and the surface of an interdigital electrode is coated with the gas sensitive material to prepare a sensing device. The composite material combines abundant active sites brought by high specific surface area of the SnO2 hollow spheres and excellent room temperature conductivity of the PPy nanotubes, and effectively solves the problems of high working temperature and large energy consumption of a traditional metal oxide sensor. Tests show that the sensor has the characteristics of quick response and short recovery time to H2S gas at room temperature. In addition, the preparation process is simple, raw materials are cheap and easy to obtain, and the method is suitable for large-scale production and has wide application prospects in the fields of industrial safety monitoring and environment detection.

The invention relates to the technical field of electronic cigarettes, and discloses an electronic cigarette essence sheet based on efficient environment-friendly low-temperature polymer volatilization and a manufacturing process thereof.The essence sheet comprises a composite material with polylactic acid as a matrix, and modification of the polylactic acid comprises compounding with aluminum oxide nanoparticles so as to improve the thermal stability of the polylactic acid; the composite material further comprises essential oil in a certain proportion, and the essential oil is used for volatilizing at a controlled rate and under a low-temperature condition in the heating process by being combined with a specific chemical bond of polylactic acid; the volume fraction of the aluminum oxide nanoparticles is accurately controlled to be 5%, and more uniform heat distribution is realized by enhancing the heat conductivity of the composite material, so that the volatile performance of the essence is optimized. The aluminum oxide nanoparticles are introduced into a polylactic acid matrix, so that compared with a pure polylactic acid material, the heat conductivity coefficient is increased by about 3 times, and the problem of local overheating or non-uniform essence volatilization caused by poor heat conduction of a traditional essence tablet is solved.

The utility model discloses a top illumination reactor, including outer tube structure, the outer tube structure includes outer tube body, and the upper end side of outer tube body is connected with the air inlet pipe, and the upper and lower both ends of outer tube body are connected with upper butt joint and lower butt joint respectively, the light guide column is arranged in the inside of outer tube body, the diameter of light guide column is less than the cavity diameter of outer tube body, and the lower end of light guide column is provided with hopper, the utility model belongs to photocatalysis technical field, and the utility model discloses the purpose at in the existing technology two sides circular light window place poor tightness and the characterization test of being not conducive to catalyst recovery after, and the uneven distribution of liquid film will also influence the mass transfer efficiency problem. The technical effect for reaching is: through optimizing the illumination conduction and catalyst contact structure, the photocatalytic reaction efficiency is improved significantly, adopts the top illumination design cooperation with light block and conical structure, can disperse the light source into uniform large area illumination, ensures the light uniformity of catalyst bed layer.

This invention discloses a polyaniline-coated copper-based Prussian blue analog composite cathode material, its preparation method, and its application in secondary seawater batteries. The cathode material uses carbon cloth as a conductive substrate. First, a copper layer is formed on the surface of the carbon cloth by electrodeposition, followed by oxidation to obtain copper oxide nanosheets. Then, copper-based Prussian blue analog nanosheets are generated through in-situ conversion induced by potassium ferricyanide and ligands. Finally, aniline is oxidatively polymerized under acidic and low-temperature conditions to construct a polyaniline conductive coating layer on the surface of the copper-based Prussian blue analog nanosheets, resulting in the CuHCF@PANI / CC composite cathode material. This material combines a three-dimensional open nanosheet array structure with a uniform polyaniline protective layer, effectively improving electron transport capability, reducing the desolvation barrier of hydrated metal ions and interfacial transport resistance, buffering volume changes during charge and discharge, and suppressing the dissolution of active materials and electrolyte side reactions. This cathode material is suitable for secondary seawater batteries using seawater as the electrolyte, exhibiting high specific capacity, rate performance, and cycle stability, which is of great significance for the development of safe, low-cost, and sustainable energy storage technologies.

The utility model discloses a discharge door structure for an internal mixer production line, which comprises an internal mixer discharge port, a wheel rolling machine feed port and a rack, a cabin door device is mounted in the rack, the internal mixer discharge port is arranged above the cabin door device, and the wheel rolling machine feed port is arranged below the cabin door device; the cabin door device comprises a discharging door, a driving assembly, a sliding cabin door and a crank connecting rod assembly, the discharging door is rotationally installed on the inner wall of the rack, the driving end of the driving assembly is connected with the discharging door, the sliding cabin door is located above a feeding port of the wheel rolling machine, and the crank connecting rod assembly is connected with the discharging door and the sliding cabin door. When the discharging door is closed, the crank connecting rod assembly drives the sliding cabin door to synchronously close the feeding port, synchronism and coordination of the discharging process and the feeding process are guaranteed, the problem of material leakage or blockage caused by asynchronous actions of the discharging process and the feeding process is solved, the operation stability and reliability of equipment are remarkably improved, and the problems that a feeding port of a traditional wheel rolling machine is normally open and cannot be closed are solved. And the problem that materials are polluted is solved.

The invention provides a high-dispersion high-rate polyanion sodium battery positive electrode material and a preparation method thereof, the positive electrode material comprises ferric sodium pyrophosphate and carbon, and meets one or more of the following conditions: (1) the positive electrode material exists in the form of primary single crystal particles; (2) the D50 of the positive electrode material is 0.5-2.5, and the D90 of the positive electrode material is 1-5; (3) the compaction density of the positive electrode material is 2.0-2.1 g / cm < 3 >; (4) the molecular formula of the ferric sodium pyrophosphate in the positive electrode material is Na4Fe3 (PO4) 2P2O7; and (5) the carbon content of the positive electrode material is 1.0-2.5 wt%. According to the preparation method, anhydrous iron-phosphorus compounds are adopted as precursors, and the interaction among particles is greatly weakened by virtue of weak interaction among the anhydrous iron-phosphorus compounds, synergistic particle size regulation and low-temperature sintering, so that primary small ferric sodium pyrophosphate particles which are regular in morphology and highly dispersed are prepared; and gaps caused by loose aggregation among the primary particles are eliminated, so that the prepared positive electrode material has relatively high compaction density.

The invention discloses a lithium iron phosphate positive electrode material, a preparation method thereof and a battery, and belongs to the technical field of batteries, the preparation method comprises the following steps: mixing an iron source, a lithium source, a phosphorus source, a dopant and a grinding agent, and carrying out dry ball milling to obtain precursor powder; and sintering the precursor powder under the protection of inert gas to obtain the lithium iron phosphate positive electrode material. According to the method, high-purity graphite / acetylene black is used as a grinding agent and a carbon source, a doping agent is added at the same time, a solvent does not need to be used, a ball-milled material does not need to be dried, uniform compounding of a precursor and construction of a conductive network are achieved in one step through the mechanochemical effect, and then the conductive network is obtained through high-temperature sintering. The prepared lithium iron phosphate positive electrode material has excellent electrochemical performance and relatively high compaction density, and still keeps relatively good electrochemical performance in a low-temperature environment, so that a new development direction is provided for production of lithium iron phosphate.

The invention belongs to the technical field of negative electrode materials, and relates to a preparation method and application of an amorphous metal oxide nanorod negative electrode material. The preparation method of the amorphous metal oxide nanorod negative electrode material comprises the following steps: uniformly mixing an organic ferric salt and an organic manganese salt, adding an organic ligand, stirring until precipitate appears, cleaning the precipitate, performing freeze drying, and then performing heat treatment to obtain the amorphous metal oxide nanorod negative electrode material. By adopting the nanorod structure, more reaction sites can be provided so as to promote the intercalation and deintercalation rates of lithium ions; due to the one-dimensional characteristic of the nanorod, the diffusion path of lithium ions in the material is shortened, and the rapid charging and discharging capacity is enhanced. In addition, the amorphous structure is adopted, so that the mechanical stress of the material can be reduced, and the cycling stability is improved; the electronic conductivity is superior to the performance of the same crystal state, and the overall conductivity of the battery can be effectively improved.

The present application relates to a resin-assisted gradient-doped LMFP positive electrode material, a preparation method and a positive electrode, the preparation method comprising: mixing a sulfonic acid type cation exchange resin with a mixed salt solution, loading metal ions on the sulfonic acid type cation exchange resin, washing to obtain a loaded resin; heat treating the loaded resin to uniformly disperse metal oxides, and then mixing with a phosphoric acid solution to obtain a mixed solution; the mixed solution is dried by spray drying to obtain a precursor powder; mixing a lithium source, a nitrogen-doped carbon source and the precursor powder, and wetting with a glucose solution to form a slurry mixture; after the slurry mixture is dried, sintering is performed to obtain the resin-assisted gradient-doped LMFP positive electrode material. The present application can inhibit the Jahn-Teller distortion of Mn, and improve the cycle stability and conductivity of the positive electrode material.

This invention discloses a method for preparing lithium iron phosphate using iron hydroxyl oxide as an intermediate, belonging to the field of new energy battery materials. The method includes: removing impurities from a ferrous sulfate solution, adding ammonium bicarbonate and ammonium fluoride, heating and passing an oxidizing gas to react and generate the iron hydroxyl oxide intermediate; mixing and milling this intermediate with a phosphorus source, a lithium source, and a carbon source, spray drying, and sintering under an inert atmosphere to obtain lithium iron phosphate cathode material. This invention uses iron hydroxyl oxide as the sole iron source, eliminating the need for the iron phosphate intermediate throughout the entire process. In step two, ammonium fluoride is used for in-situ doping with fluorine, and combined with the structural template effect of the nanorod-shaped iron hydroxyl oxide, uniform nanoparticles are obtained with only one milling operation, forming microporous channels. This method simplifies the production process, reduces equipment investment and energy consumption, and the resulting material exhibits high capacity, high initial efficiency, and excellent rate performance.