46results about How to "Improve surface chemistry" patented technology

The invention belongs to the technical field of a lithium ion battery, and relates to a silicon carbon negative electrode material and a preparation method therefor, and the lithium ion battery. The preparation method for the silicon carbon negative electrode material comprises the following steps of (a), by taking silicon monoxide as the substrate material, performing heating treatment on siliconmonoxide to enable silicon monoxide to be subjected to a disproportionation reaction to generate c-SiO; (b), putting c-SiO into a chemical vapor deposition furnace, heating in protective atmosphere until a reaction temperature is reached, and pumping a carbon source to be subjected to a vapor deposition reaction to obtain c-SiO / C, wherein the carbon source is a liquid-state or solid-state compound; and (c), performing corrosion of the c-SiO / C by a corrosive liquid to obtain the silicon carbon negative electrode material c-SiO / Si / C. The preparation method is simple in process and easy to operate; and the prepared silicon carbon negative electrode material has the high lithium storage characteristic as the silicon type material and the high cycling stability as the carbon type material, aswell as high specific capacity, high conductivity and high cycling performance.

The invention relates to a preparation method of a carbon cladding modified lithium manganate anode material. The preparation method is characterized by comprising the following steps of: (1) adding lithium manganate into de-ionized water; (2) adding a soluble organic carbon source which accounts for 10-30% of the mass of lithium manganate into the obtained mixed solution; then adding a carbonizing catalyst which accounts for 0.5-5% of the mass of the soluble organic carbon source; (3) spraying and granulating the obtained mixed solution through a spraying drying machine; and (4) adding lithium manganate powder into a crucible, sintering at 300-450 DEG C for 0.5-4 hours and then cooling to obtain the product. According to the preparation method disclosed by the invention, the situation that a lithium manganate crystal form is damaged by high-temperature carbonization is avoided, and metal is reduced and separated out. The electrode conductivity is effectively improved, the surface chemical performance of an active material is improved and an electrode is prevented from directly contacting an electrolyte solution, so that the better circulating service life can be obtained.

The invention discloses a polyamide composite fiber with an intelligent surface and its preparation method and application. The polyamide composite fiber includes a polyamide fiber matrix and particles covering it. In this way, covering the particle on the surface of the fiber matrix can improve fiber The roughness, and then improve the hydrophilic and hydrophobic properties of the fibers, so that the poor dimensional stability of polyamide fibers caused by strong hygroscopicity is improved. The preparation is carried out as follows: first obtain the polyamide fiber matrix with reactive groups on the surface, then obtain particles with reactive functional groups, and finally mix the polyamide fiber matrix with the particles for reaction to obtain the polyamide composite fiber. The polyamide composite fiber of the present invention can be used in smart textiles, non-woven fabrics, porous membranes, composite materials and oil-water separators, preferably smart textiles and oil-water separators.

The invention discloses a carbon-coated ternary cathode material. The chemical formula of the carbon-coated ternary cathode material is LiNi<x>Co<y>Mn<z>O<2>, wherein 0.2<=x<=0.7, 0.1<=y<=0.5, 0.2<=z<=0.3, and x+y+z=1. The outer surface of the carbon-coated ternary cathode material is coated with a carbon carbon network. The invention also provides a preparation method. The carbon-coated ternary cathode material is capable of improving electrode electrical conductivity effectively, improving surface chemical properties of active materials, protecting electrodes from direct contact with electrolyte, and prolonging cycle life.