35results about How to "Reduce electrochemical activity" patented technology

The present invention relates to a positive electrode material for secondary battery and the preparation method thereof, wherein the said positive electrode material comprises Li_xNi_1−y−zCo_yMe_zO_2±n as the main component, 0.9≦x≦1.1, 0<y≦0.3, 0≦z≦0.1, 0≦n≦0.1 and Me is selected at least one or two elements from the group consisting of Mg, Zn, Mn, Co, Al and Ca in the formula, and Li_vNi_1−aMe′_aO_2±m or Li_xNi_1−yMe″_yPO₄ existed on the polycrystalline surface of the main component and/or among the crystal phase of the main component. The proportion of peak intensity ratio of (003) to (104) of the positive electrode material in the polycrystalline X-ray diffraction spectrum is 2.0≦I₍₀₀₃₎/I₍₁₀₄₎≦3.0. The secondary battery comprising said positive electrode material is liquid, solid or polymer lithium secondary battery or lithium ion battery.

The invention provides a lithium alloy strip and a preparation method thereof. The lithium alloy strip comprises a uniformly mixed metal lithium elemental substance and a transition metal elemental substance of micro-nano structure; The preparation method comprises the following steps: (1) Heating the metal lithium to a molten state in an environment having the dew point not higher than -50 DEG CAND having an oxygen content of not more than 10 ppm; (2) adding the transition metal into the molten metal lithium, and uniformly mixing to form a molten alloy state; 3) cooling to room temperatureto obtain lithium alloy material; 4) heating that lithium alloy material obtained in the step 3) to 30-500 DEG C; (5) processing the lithium alloy into an alloy strip with a thickness of 1 to 100 [mu]m. The preparation method is simple and feasible, the cost is low, and the prepared metal lithium alloy strip has higher hardness, strength and better processing performance than the lithium strip, and can be applied in a metal lithium battery to effectively improve the coulomb efficiency and cycle life of the battery.

The invention relates to a preparation method for polyaniline, which solves the technical problems of complex process, low product polymerization degree and poor electric conductivity in existing polyaniline. The preparation method comprises the following steps: dispersing inorganic acid in water; adding an antifreezing agent into a mixture while stirring; cooling the mixture to a temperature below 0 DEG C and then adding aniline into the mixture; after a solution is stirred and reacted, adding manganese dioxide into the solution; uniformly dropwise adding a persulfate solution; then carrying out suction filtration; washing a product by using deionized water and hydrochloric acid, respectively; and drying the product in vacuum to obtain polyaniline. The preparation method for polyaniline can be widely used for preparation of electrode materials.

The invention discloses an aspirin molecule imprint electrochemical sensor and a preparation method thereof. The molecule imprint technology is combined with the electroanalysis chemical detection technology for use, aspirin serves as template molecules, acrylamide serves as functional monomers, and rosin, one of the characteristic resources in Guangxi province, is tightly combined and serves as the raw material for synthetizing maleated rosin acrylic acid glycol ester which is used as a cross linker. The aspirin molecule imprint electrochemical sensor can be used for measuring content of aspirin, and shows better selective identification performance; and an electrochemical analysis method for measuring aspirin based on the sensor is simple and practical, and overcomes the defect that the traditional method is complicated.

The invention discloses a preparation method for a polypyrrole-poly-dopamine composite coating. The preparation method includes the following steps that (1) dopamine and a dopant are dissolved into deionized water, then a pyrrole monomer without impurities is continuously added to be dissolved, dry nitrogen is then led in to remove dissolved oxygen in a mixture, and an electrolyte with the pH ranging from 1 to 8 is obtained; and (2) in the above electrolyte, a constant potential polymerization process is adopted for conducting polymerization on the surface of one side of a pure titanium substrate to obtain the polypyrrole-poly-dopamine composite coating, and oxide, miscellaneous dirt and grease on the surface of the pure titanium substrate are removed through pretreatment. According to the method, an electrochemical method is adopted for conducting polymerization on the dopamine and the pyrrole, the polymerization time is short, polymerization can be carried out under the acidity and alkaline conditions, and meanwhile a polymerization film obtained through polymerization has some beneficial effects of the dopamine and the pyrrole; and a larger possibility is provided for potential application of the polymerization film.

The invention provides a lithium alloy anode material and a preparation method thereof. The preparation method comprises the following steps: in an environment that the dew point is not higher than 50DEG C below zero and the oxygen content is not higher than 10 ppm, heating the lithium metal to a melting state; adding transition metal into the molten lithium metal, performing heat preservation for 5 minutes to 15 minutes, and uniformly mixing to form a molten alloy state; cooling the molten state alloy to room temperature to obtain the lithium alloy anode material. The preparation method disclosed by the invention has the advantages of simplicity, feasibility and low cost; when being applied to a lithium battery, the prepared lithium metal alloy anode material can effectively improve thecoulomb efficiency of the battery and prolong cycle life of the battery.

The invention discloses a sintered NdFeB magnet surface temporary protection organic coating and a preparation method thereof. A prepared silicyl organic protection thin film is modified through a compounding mode of anode metal nanoparticles such as Al and Zn; by means of the compounding of the nanoparticles, the porosity of the thin film can be remarkably reduced, and the uniformity and consistency of the magnet surface silicyl organic protection thin film are improved; meanwhile, anode metal nanometer Al powder and nanometer Zn powder are compounded in the silicyl organic protection thin film, in the efficacy-loss early period of a protection layer, the electrochemical activity of nanometer Al and nanometer Zn is remarkably higher than the electrochemical potential of an NdFeB base body, and therefore sacrificial anode protection can be provided for the base body in the electrochemical corrosion environment, corrosion protection can continue to be provided for the magnet, the anticorrosion performance and the mechanical performance of the magnet surface silicyl film are further improved, and finally the surface temporary anticorrosion organic coating with excellent comprehensive performance is obtained.

The invention relates to a boron-doped lithium nickel cobaltate anode material. The chemical formula of the boron-doped lithium nickel cobaltate anode material is LiNiXCoYBZO2, wherein 0.7<X<0.9, 0.1<Y<0.3, 0<Z<0.1, and X+Y+Z=1. The preparation method of the boron-doped lithium nickel cobaltate anode material comprises the following steps: 1. proportionally mixing a compound containing nickel, cobalt and lithium and a compound containing boron; 2. in an air atmosphere, pretreating at 300-600 DEG C for 1-10 hours; 3. in an oxygen atmosphere, synthesizing at the high temperature of 700-850 DEG C for 3-15 hours; and 4. cooling to normal temperature, pulverizing, and screening to obtain the final product. In the boron-doped lithium nickel cobaltate anode material provided by the invention, boron is used instead of metal doping ions, thereby enhancing the first capacity, first discharging efficiency, cycle performance and safety of the material; and the method provided by the invention has the advantages of simple production technique, fewer steps, short production time, low energy consumption, no pollution and zero discharge, thereby being very suitable for industrial production.

The present invention relates to the field of lithium ion batteries, especially provides application of hydroxyl compound in a high-voltage lithium ion battery and a high-voltage lithium ion battery.The high-voltage lithium ion battery comprises at least one of a functional additive for a high-voltage lithium ion battery, a high-voltage lithium ion battery electrolyte or high-voltage lithium ionbattery positive electrode slurry, the high-voltage lithium ion battery electrolyte and high-voltage lithium ion battery positive electrode slurry comprise the functional additive for the high-voltagelithium ion battery e, and the functional additive comprises a hydroxyl compound. The hydroxyl in the hydroxyl compound is reacted with the Li in the lithium ion battery positive electrode material to form an SEI film with good performances and the SEI film can effectively inhibit the reaction between the electrolyte solvent and the positive electrode materials so as to improve the cycle performance of the lithium ion battery.

The invention relates to a preparation method of a dicyandiamide molecular imprinting polymer membrane electrode. The preparation method comprises the following steps of carrying out electropolymerization by a tri-electrode system, preparing a polymer membrane from dicyandiamide as a template molecule and o-aminophenol as a functional monomer, depositing the polymer membrane on the surface of an electrode, and removing the template molecule on the electrode so that the dicyandiamide molecular imprinting polymer membrane electrode with template molecule-type holes is prepared. The preparation method is a high-selectivity high-sensitivity high-adsorption capacity method for preparing the dicyandiamide molecular imprinting polymer membrane electrode on the surface of a gold electrode from o-aminophenol as a functional monomer by an electropolymerization method. The dicyandiamide molecular imprinting polymer membrane electrode can be used for determination of dicyandiamide content and has good selective identifiability. The dicyandiamide determination electrochemical analytical method utilizing the dicyandiamide molecular imprinting polymer membrane electrode has simple and practical processes and solves the problem that the original method has complexity.

The invention discloses a preparation method of a sintered neodymium-iron-boron magnet with high corrosion resistance and high coercive force, which comprises the following steps: fully mixing neodymium-iron-boron alloy powder with nanoscale low-melting-point metal according to a certain mass ratio, putting the mixture into a magnetic field of 1.8 T or above, and carrying out oriented compression to obtain a pressed blank; and then carrying out high-temperature sintering on the pressed blank, carrying out grain boundary diffusion heavy rare earth treatment on the prepared sintered neodymium-iron-boron magnet, and finally carrying out tempering heat treatment. According to the preparation method, the grain boundary is doped with the nanoscale low-melting-point metal, so that the chemical activity of a grain boundary rare earth-rich phase can be reduced; in addition, a smoother diffusion channel is provided for grain boundary diffusion, so that the problem of grain boundary diffusion depth is solved, and controllable preparation of the sintered neodymium-iron-boron magnet with high corrosion resistance and high coercivity is realized.

This invention relates to a manganese bioxide electrolysis modification method of lithium battery, which is characterized by the following: the electrolyzed gamma-MnO#-[2] powder is protected in the oxygen of 95 to 100 percent and is calcined with high temperature of 370 to 380 degrees; it forms the convection of oxygen in high temperature space for 24 hours.

The invention relates to an electrochemical preparation method of a phenylamine-4-aminosalicylic acid copolymer. The following three electrode electrolytic cells are used: a glassy carbon electrode used as a working electrode, a platinum electrode used as an auxiliary electrode and a saturated calomel electrode used as a reference electrode; electrolyte is a mixed solution of 0.10-0.50 mol.dm-3 of phenylamine, 0.01-0.02 mol.dm-3 of 4-aminosalicylic acid and 1.50-2.50 mol.dm-3 of sulfuric acid; and electrolysis is carried out by a cyclic voltammetry, and an obtained electrolytic product is washed and dried to obtain the phenylamine-4-aminosalicylic acid copolymer. The phenylamine-4-aminosalicylic acid copolymer prepared by the method still has good electrochemical activity in a high-alkaline solution of which pH is 9.0-11.0. Moreover, the preparation method is convenient to control and easy to implement.

The invention provides a ternary anode material and a preparation method and application thereof, a lithium ion battery and an electric vehicle, and belongs to the technical field of lithium ion batteries. The ternary anode material comprises a ternary material and a coating layer coating the surface of the ternary material, wherein the coating layer comprises M1y+2z-2xM2xR1yR2z and graphene; M1 and M2 are metal elements, and R1 and R2 are anions containing phosphorus and/or sulfur. The graphene has excellent conductivity and improves the migration rate of metal ions to ions, so that the surface impedance of the ternary anode material can be effectively reduced; and the coating layer can effectively reduce the surface electrochemical activity of the anode material in a cycle process, increase the surface conductivity of the anode material, inhibit the corrosion effect of electrolyte decomposition products on the surface of the anode material, inhibit the dissolution of transition metalions and stabilize the structure of the anode material, the cycle stability and multiplying power performance of the lithium ion battery under high temperature and high voltage are improved.