13results about How to "Improve sodium storage performance" patented technology

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.

The invention belongs to the technical field of hard carbon materials, and particularly relates to a preparation method and application of a polyurethane-based hard carbon material. The preparation method comprises the following steps: carrying out roasting carbonization and post-treatment on a solid polyurethane material at 900-1400 DEG C to obtain a powdery polyurethane-based hard carbon material; the solid polyurethane material is a polyurethane product prepared from reaction raw materials including isocyanate, non-phosphorus-containing polyol and phosphorus-containing polyol through a reaction. According to the invention, the polyurethane material is prepared by adding the phosphorus-containing polyol, and the polyurethane material is applied to the field of batteries as a negative electrode raw material, so that high carbonization yield can be maintained, and excellent performances such as initial coulombic efficiency, energy density, cycle capacity retention rate and the like of the battery can be realized.

The application relates to a sodium titanate nanofiber / reduced graphene oxide composite electrode material and a preparation method and application thereof. The composite electrode material has a two-dimensional sheet structure, the particle size is 1-6 mu m, the thickness is 10-20 nm, is composed of a few-layer reduced graphene oxide and sodium titanate nanofibers with a diameter of 5-10 nm loaded on the reduced graphene oxide, and is prepared by taking the few-layer reduced graphene oxide as a template, uniformly loading titanium dioxide particles, and then carrying out hydrothermal treatment in an alkali solution. Compared with the prior art, the synthesis method is simple in process, easy to scale up, and high in controllability. As a negative electrode of a sodium ion battery or a positive electrode of a sodium battery, the sodium titanate nanofiber / reduced graphene oxide composite electrode material has the advantages of high initial coulomb efficiency, low working voltage, high capacity, excellent rate characteristics and cycle stability, and has a broad market application prospect.

The invention discloses a tungsten sulfide / carbon composite negative electrode material and a preparation method and application thereof, and belongs to the technical field of sodium ion battery negative electrode materials. The preparation method comprises the following steps: taking bagasse as a raw material, preparing a spherical carbon material through pretreatment, acidic hydrothermal treatment and high-temperature calcination, coating polyaniline through in-situ chemical oxidation polymerization, and then carrying out secondary polymerization and calcination to obtain a carbon matrix CNS (at) PAN (at) CS; and then carrying out hydrothermal reaction and high-temperature calcination on the carbon substrate, a tungsten source and a sulfur source, and growing WS2 nanosheets on the surface of the carbon substrate in situ to form a multi-dimensional network structure. The method is simple in process, low in cost and environment-friendly, provides a new method for large-scale application of the sodium ion battery, and has a good application prospect.

The application discloses a carbon nanotube multi-metal sulfide negative electrode material and a preparation method and application thereof. In the application, dicyandiamide is dissolved in water, a transition metal chloride salt is added and stirred to uniformly disperse, the solution is dried, and a powder is obtained through grinding; the powder is calcined at high temperature under an inert atmosphere, and after cooling, a sulfur source is added, sulfurization treatment is carried out at high temperature, and the carbon nanotube multi-metal sulfide negative electrode material is obtained after cooling. In the application, dicyandiamide is used as the only carbon source, the prepared carbon nanotube multi-metal sulfide negative electrode material has a high specific capacity as a sodium ion battery negative electrode material, greatly improves the rate performance of the sodium ion battery negative electrode material, and greatly improves the cycle stability at a high rate.

The application discloses a preparation method of a biomass hard carbon negative electrode material, and comprises the following steps: (1) pre-carbonizing a biomass raw material, and then uniformly mixing the pre-carbonized biomass raw material with an alkali solution to obtain wet material; (2) high-temperature carbonizing the wet material in an inert atmosphere, and then rapidly cooling the high-temperature carbonized wet material to obtain carbonized biomass; the cooling rate is controlled to be 10-30 DEG C / min during the rapid cooling; and (3) physically stripping the crystalline substances on the surface of the carbonized biomass, and then crushing the carbonized biomass to obtain the biomass hard carbon negative electrode material. The biomass hard carbon needs high-temperature carbonization during processing, and the high-temperature carbonization process is used for impurity removal, so that the energy consumption is not additionally increased. The impurities are separated by using a physical method, and the process is simple and environment-friendly. Overall, the material prepared by the method has low impurity content, excellent sodium storage performance, low energy consumption in the preparation process, simple process and environment-friendly.

The invention relates to the field of sodium ion batteries, and discloses a preparation method and application of a ferrocobalt bimetallic sulfide nitrogen-doped porous carbon framework composite material. The preparation method comprises the following steps: by taking aminotriacetic acid as a ligand, chelating cobalt and iron ions through ball milling to prepare a CoFe-NTA precursor; the precursor is pyrolyzed, metal ions are subjected to carbon thermal reduction, and nitrogen-doped carbon formed by in-situ conversion of nitrilotriacetic acid can be tightly combined with ferrocobalt sulfide, so that the volume change generated during deintercalation of sodium ions can be effectively relieved, the cycling stability of the material can be enhanced, and the conductivity and the sodium ion diffusion rate of the composite material can be improved; and carrying out gas-phase vulcanization to finally obtain the ferrocobalt bimetallic sulfide nitrogen-doped porous carbon framework composite material. The nitrogen-doped porous carbon framework is beneficial to contact between electrolyte and an electrode material, active sites are fully utilized, the structural stability of the composite material can be enhanced, and when the nitrogen-doped porous carbon framework is used as a sodium-ion battery negative electrode, the nitrogen-doped porous carbon framework shows excellent sodium storage performance.

The application provides a pitch-based carbon negative electrode material and a two-step pre-oxidation synthesis preparation method and application thereof. The two-step pre-oxidation synthesis preparation method of the pitch-based carbon negative electrode material comprises the following steps: uniformly grinding and mixing a pitch precursor and an initiator to obtain a mixed precursor; performing heat treatment on the mixed precursor in an oxidizing atmosphere, cooling and cooling down to obtain a pre-oxidized precursor I; mixing the pre-oxidized precursor I with an oxidizing agent in a liquid phase to perform secondary oxidation to obtain a pre-oxidized precursor II; performing calcination on the pre-oxidized precursor II in an inert gas atmosphere, cooling, grinding, washing and drying to obtain the pitch-based carbon negative electrode material. The pitch-based carbon negative electrode material comprises a product prepared by the above method. The method provided by the application introduces oxygen functional groups into the pitch precursor through two-step pre-oxidation, crosslinks with pitch molecules, hinders carbon layer rearrangement, reduces the graphitization degree after carbonization, improves the sodium storage capacity, enhances the surface capacitance contribution and improves the rate capability.

The application discloses a kind of spherical sulfurized polyacrylonitrile-based hard carbon negative materials and preparation method and application thereof, and it is related to sodium ion negative material preparation technical field.The preparation method of the application includes: first, polyacrylonitrile and sulfur sublimate are added into ball mill jar in certain proportion and ball milled, then dried, finally placed in the tube furnace with inert atmosphere protection and carried out two-step heat treatment, finally obtain hard carbon negative material, the application also provides the application of the hard carbon negative material in the preparation of sodium ion battery.The application aims to prepare S-doped polyacrylonitrile-derived hard carbon material by sulfurizing treatment of polyacrylonitrile and sulfur sublimate, and then carbonizing at high temperature (>1200 DEG C).The preparation method provided by the application is simple, easy to operate, and the raw material carbon yield is high.The hard carbon negative electrode is prepared by ball milling and two-step heat preservation method, and has the advantages of high initial coulomb efficiency, good cycle performance and high rate performance.

The application relates to a preparation method and application of a hard carbon negative electrode material micro-pore structure regulator. The preparation method comprises the following steps: placing a hard carbon precursor material in a closed reactor to perform a preliminary reaction to obtain a pre-product, wherein the filling degree of the hard carbon precursor material in the closed reactor is greater than or equal to 40%; when the filling degree is 40%, the temperature of the preliminary reaction is 350 DEG C-450 DEG C, and when the filling degree increases by 5%, the temperature of the preliminary reaction is relatively reduced by 20 DEG C-25 DEG C; and the pre-product is sequentially subjected to a first carbonization treatment and a second carbonization treatment under a protective atmosphere to obtain a hard carbon negative electrode material. The application provides a simpler preparation method, and the prepared hard carbon negative electrode material has rich closed nano-pore structure, so that the sodium storage performance of the negative electrode material is improved.

This invention discloses a method for preparing biomass hard carbon anode materials without acid washing, comprising the following steps: using pure water as a solvent, placing biomass particles in a Soxhlet extractor, continuously circulating and extracting the biomass particles under reflux conditions for 2-5 hours; after extraction, removing the solid and drying it to obtain water-extracted purified biomass; heating the obtained water-extracted purified biomass to 300-550°C at a heating rate of 2-10°C / min, holding it at this temperature for 2-5 hours, then naturally cooling it to room temperature, and then washing and drying it with pure water; heating the obtained pre-oxidized carbonized product to 1100-1550°C at a heating rate of 2-10°C / min, holding it at this temperature for 3-6 hours, and then naturally cooling it to room temperature; washing the obtained carbonized product with pure water until the filtrate is neutral, and then drying it. Compared with the prior art, this method solves the problems of serious wastewater pollution, significant safety hazards, high costs, long production cycles, and the easy introduction of oxygen-containing defects that damage electrochemical performance.

The invention provides a high-specific-capacity hard carbon material as well as a preparation method and application thereof. The high-specific-capacity hard carbon material is prepared from raw materials including a phenolic compound, an aldehyde compound, a catalyst and a curing agent, the preparation method comprises the following steps: (1) uniformly mixing a phenolic compound, an aldehyde compound and a catalyst in water, and reacting to obtain a low-molecular-weight resin solution; (2) adding an amine curing agent into the low-molecular-weight resin solution obtained in the step (1), uniformly mixing, and carrying out hydrothermal reaction to obtain high-molecular-weight cross-linked resin; and (3) carrying out low-temperature calcination on the high-molecular-weight cross-linked resin obtained in the step (2) in an oxygen-containing gas atmosphere, then carrying out high-temperature calcination in a protective gas atmosphere, and cooling to room temperature to obtain the high-specific-capacity hard carbon material. The prepared high-specific-capacity hard carbon material is high in reversible specific capacity, the first coulombic efficiency and the rate capability are kept at a high level, and the comprehensive sodium storage performance is excellent.

The application relates to the technical field of electrochemical materials, in particular to a preparation method of a tungsten disulfide / graphene composite material and application thereof. Based on surface modification, coprecipitation and a high-temperature kettle reaction method, tungsten salt is deposited on the surface of silicon balls modified by graphene oxide, a high-temperature sulfuration reaction is carried out, and then the tungsten disulfide / graphene composite material is obtained after being treated with an alkali solution and an acid solution in sequence. The preparation method has the characteristics of simple operation and easy mass production, meanwhile, the tungsten disulfide / graphene composite material prepared by the method has the characteristics of three-dimensional multi-level porous structure, and when the material is used as a negative electrode material of a sodium ion battery, excellent performance and wide application prospect are exhibited.