57 results about "Sodium manganate" patented technology

The invention belongs to the technical field of energy storage devices, and in particular relates to flexible water-based sodium-ion batteries and a preparation method thereof. The flexible water-based sodium-ion batteries take sodium manganate as a positive active material and carbon-coated sodium-titanium phosphate as a negative active material; the flexible water-based sodium-ion batteries with excellent electrochemical performance are prepared from the sodium manganate and the carbon-coated sodium-titanium phosphate according to an appropriate mass ratio; the two types of flexible water-based sodium-ion batteries are a two-dimension band-shaped flexible water-based sodium-ion battery and a one-dimensional thread-shaped flexible water-based sodium-ion battery. The band-shaped flexible water-based sodium-ion battery takes soft stainless steel as a current collector; the thread-shaped water-based sodium-ion battery enables the active materials to be rolled into an orientation carbon nano tube (CNT) to prepare composite fibers, and the CNT is used as a current collector and a conductive additive at the same time, so that the mass and volume of the battery are reduced, the flexibility of the battery is improved, and the thread-shaped water-based sodium-ion battery is easy to weave and integrate. The two-dimension band-shaped flexible water-based sodium-ion battery and the one-dimensional thread-shaped flexible water-based sodium-ion battery have excellent electrochemical performance, and have the advantages of being light in mass, low in cost, high in flexibility and safety, environmental-friendly, and the like, thus providing possibility for the application in the field of wearable electronic devices. The thread-shaped flexible water-based sodium-ion battery can even be implanted in a human body for assisting health monitoring and treatment of diseases.

The present invention provides a hollow spherical sodium nickel manganate and a preparation method thereof, a sodium ion battery positive electrode, and a sodium ion battery, which belongs to the technical field of sodium ion batteries. The present invention provides a hollow spherical sodium nickel manganate having a particle diameter of 2.5-3.5 micrometer, a wall thickness of 0.5-1.0 micrometer,and a smooth outer surface. A chemical composition of the hollow spherical sodium nickel manganite is NaxNiyMnzO2, where x:y:z=2:1:3. The sodium nickel manganate provided by the present invention hasa hollow spherical structure with regular morphology and high crystallinity, which is beneficial for sodium ions to rapidly enter a solid phase medium from the surface, a diffusion path between solidphase particles is shortened. The sodium ion battery assembled from the sodium ion battery positive electrode obtained by using the hollow spherical sodium nickel manganate as a raw material has excellent cycle stability and rate performance.

The invention discloses a method for preparing a graphene / sodium manganate flexible thin film and a method using the graphene / sodium manganate flexible thin film to prepare an aqueous sodium-zinc compound battery, relates to methods for preparing graphene thin films and methods using the graphene thin films to prepare compound batteries, and aims to solve the problem that an existing battery anode material is complex in preparation process, low in conductivity and unstable in electrochemical performance. The method for preparing the graphene / sodium manganate flexible thin film includes the steps of firstly, preparing Na4Mn9O18 powder; secondly, adding graphene oxide into deionized water, and performing ultrasonic treatment to obtain a solution A; thirdly, preparing a graphene oxide / sodium manganate flexible thin film; fourthly, drying the graphene oxide / sodium manganate flexible thin film to obtain the graphene / sodium manganate flexible thin film. The prepared graphene / sodium manganate flexible thin film is simple in process, has sufficient toughness, can be curled at will and can be directly cut to serve as a flexible electrode. By the methods, the graphene / sodium manganate flexible thin film and the aqueous sodium-zinc compound battery can be prepared.

The invention relates to the technical field of electrode materials, in particular to a polypyrrole-coated porous sodium manganate composite material, a preparation method and application thereof. Thepolypyrrole-coated porous sodium manganate composite material comprises porous sodium manganate and polypyrrole coated on the surface of the porous sodium manganate; and the porous sodium manganate is cubic, and the chemical formula thereof is Na<x>MnO2, wherein x is equal to 0.91. The polypyrrole-coated porous sodium manganate composite material disclosed by the invention has good electrochemical cycling stability and rate performance as a positive electrode material of a sodium ion battery. The invention further provides a preparation method of the polypyrrole-coated porous sodium manganatecomposite material. The preparation method can be carried out at a low temperature, and energy can be effectively saved.

The invention provides a hydro-thermal synthesizing method for iron sodium manganate of an electrode material of an aqueous cationic battery and a preparation method of the aqueous battery. The method provided by the invention comprises the following steps of: (1) preparing an iron-sourced compound and a manganese-sourced compound into 0.5 mol / L of solution, mutually mixing, simultaneously, adding ammonium bicarbonate and ethanol as dispersing agents, and strongly stirring for 1 h; (2) transferring the mixed solution obtained in the step (1) into a reaction kettle to carry out hydro-thermal reaction, and carrying out suction filtration, cleaning and drying on the obtained precipitate; (3) ball-milling and mixing the dried product and a sodium-sourced compound in the stoichiometric ratio for 3-10 h; and (4) putting the ball-milled mixture into a muffle to be pre-processed and roasted at high temperature to obtain a final product Na0.3Fe0.5Mn0.5O2, NFMO for short. Electrochemical tests prove that the electrode material provided by the invention is maximally up to 340 mAh / g in 1 mol / L of Na2SO4 electrolyte and is maximally up to 250 mAh / g in 1 mol / L of MgC12 electrolyte under 10 mA / g of current density; the electrode material is wide in raw material and easy to prepare; and the aqueous electrolyte is low in cost, environment-friendly and non-toxic.

The invention discloses a preparation method and an application method of sodium manganate. The method comprises the following steps: adding sodium hydroxide, sodium chloride and sodium silicate into water, and dispersing manganese salt into the water; stirring, transferring into a hydrothermal kettle, carrying out hydrothermal reaction, washing with water, filtering, and drying to obtain the target product sodium manganate, wherein the molar ratio of manganese to silicon is 0.25-1. The prepared sodium manganate can be used as an inorganic ion adsorbent, and has relatively strong adsorption capacity on strontium in radioactive wastewater. The sodium manganate prepared by the method has high selectivity, adsorption capacity, mechanical property and irradiation resistance on strontium ions in radioactive wastewater, so that the strontium ions in the radioactive wastewater can be effectively removed.

A material (hereinafter referred to as “positive electrode material”) including sodium manganate powder as a positive electrode active material, carbon black powder as a conductive agent, and polytetrafluoroethylene as a binder is prepared. The positive electrode material is mixed in an N-methylpyrrolidone solution to produce slurry as a positive electrode mixture. A working electrode is produced by applying the slurry on a positive electrode collector. A negative electrode containing tin or germanium is produced. The non-aqueous electrolyte is produced by adding sodium hexafluorophosphate as an electrolyte salt in a non-aqueous solvent produced by mixing ethylenecarbonate and diethyl carbonate.

The invention belongs to the field of production of potassium (sodium) manganite. In the method, a mixed calcining material of manganese mineral powder and potassium (sodium) hydrate is oxidized by using an oxidizing gas, and the potassium (sodium) manganite is produced intermittently by adopting a gas-solid fluidized bed reactor. The method comprises the following steps of: (1) adding potassium (sodium) hydrate into manganese mineral powder serving as a raw material, stirring and calcining to obtain sintering charge; (2) milling the obtained sintering charge; (3) adding the obtained powder into the gas-solid fluidized reactor, introducing the oxidizing gas, regulating the ventilation amount to keep the powder to be in a fluidized state, keeping the temperature in the reactor to be between 220 DEG C and 300 DEG C, and reacting for 0.5-3 hours to obtain a potassium (sodium) manganite product; and (4) dissolving, stirring and standing the sintering product, performing solid-liquid separation to obtain a liquid phase which is a potassium (sodium) manganite solution and a solid phase which is unreacted manganese ore, and returning to the step (1). The method has the advantages of short process flow, simple equipment, high oxidation speed, short production period and capability of remarkably increasing the transformation rate of potassium (sodium) manganite.

The invention discloses a solid phase preparation method of sodium manganite Na2MnO3 of sodium secondary battery high voltage cathode materials. The method is characterized by comprising the following steps: grinding and uniformly mixing a manganese source compound and a sodium source compound at certain chemical stoichiometric ratio; transferring an obtained mixture into a tube furnace, and enabling the mixture to be reacted at 400 to 700 DEG C under the protection of inert gas and to be cooled to room temperature; grinding a precursor, washing the precursor to be neutral through distilled water, and performing drying, dewatering and grinding, so as to obtain the target material sodium manganite. The method has the advantages that the materials are added at one time, the technology is simple to operate, raw materials are cheap and easy to get, the product purity is high, and both the process control and product performance have good repeatability. The obtained Na2MnO3 material is high in potential platform, shows up excellent electrochemical property, and can provide a novel thought for the further research and functionization of the high energy density cathode materials.