46results about How to "Improve lithium battery performance" patented technology

The invention provides a Cu9S5@C nanocomposite material used for the negative electrode of a battery and a preparation method thereof. The preparation method comprises the following steps: with sulfur powder, copper acetate and ammonia water as reaction raw materials, carrying out a hydrothermal method so as to generate copper sulfide, carrying out annealing so as to obtain Cu9S5, coating glucose on the surface of Cu9S5 by utilizing the hydrothermal method, and carrying out annealing at a high temperature so as to obtain the Cu9S5@C nanocomposite material. According to the invention, carbon is coated on the surface of metal sulfide, so the disadvantages of poor cycle performance and stability of sulfide can be effectively compensated; cycle performance and stability of a material are improved; conductivity of the material can be increased; and the Cu9S5@C nanocomposite material used as an anode material of a lithium ion battery can effectively realize high capacity and good cycle stability and effectively improves performances of the battery. Testing results show that the lithium ion battery with the Cu9S5@C nanocomposite material prepared by using the preparation method provided by the invention as the negative electrode has good lithium-ion electric performance, stable specific capacity and good cycle performance, obtains the characteristic of fast-rising capacity after manifold cycles, and has the specific capacity increased to two times of the initial specific capacity after 90 cycles.

The invention discloses a graphene loaded transition metal silicate nano film material for a lithium ion battery and a preparation method of the nano film material. The nano film material is preparedfrom transition metal salt, a complexing agent, graphene and silicon tetrachloride in an organic alcohol phase system by a solvothermal method; a chemical formula of the nano film material is M2SiO4 / SiO2 / G; M is transition metal Mn, Fe, Co or Ni; and G is the graphene. The material is used in a lithium ion battery cathode; a two-dimensional nano film structure of the material facilitates transmission of charge in the material, and can effectively reduce volume expansion of the material in a lithium disembedding process; and high capacity and excellent cycle performance are represented.

The method of the invention discloses a porous silicon@amorphous carbon / carbon nanotube composite material, which has a core-shell structure, the inner core is a porous silicon material, the outer shell is an amorphous carbon layer, and carbon nanotubes are directly grown on the surface of the amorphous carbon layer. Adjacent carbon nanotubes are intertwined to form a conductive network. The preparation method includes: porous silicon with electronegative groups on the surface, Ni 2+ soluble salts, weakly alkaline substances and water are mixed to obtain a reaction solution, the pH of the reaction solution is controlled to be weakly alkaline, and the intermediate product A is obtained after the reaction is complete; the intermediate product A is heat-treated in an atmosphere containing hydrogen, and after reduction The intermediate product B is obtained; the intermediate product B is then subjected to chemical vapor deposition in an atmosphere containing carbon source gas, and the porous silicon@amorphous carbon / carbon nanotube composite material is obtained after post-treatment. The porous silicon@amorphous carbon / carbon nanotube composite material has excellent cycle stability and can be used as an anode material for lithium-ion batteries.

The invention discloses a method for synthesizing a silver indium sulfide heterojunction structure nano material through a hydro-thermal mode. The method comprises steps of dissolving an alcoholic suspension of silver nanowires in de-ionized water, stirring the alcoholic suspension, adding indium trichloride tetrahydrate crystal to the mixing liquid, conducting magetic stirring, adding a certain amount of surface active agent cetyl trimethyl ammonium bromide, stirring the surface active agent cetyl trimethyl ammonium bromide till the surface active agent cetyl trimethyl ammonium bromide is dissolved completely, adding a certain amount of thiacetamide, stirring the thiacetamide till the thiacetamide is dissolved completely, regarding the formed mixing liquid as a precursor solution of the silver indium sulfide heterojunction structure nano material, refluxing and heating the precursor solution in a round bottom flask with three necks by using a hydro-thermal method, changing conditions, and obtaining nano structure materials with different shapes. The reaction system is simple, the reaction temperature is low, the synthesized silver indium sulfide structure is novel, the synthesized composite material yield is high, and the reverse specific discharge capacity of the material is high when the material serves as a lithium material cathode. Besides, the method has good repeatability and operability.

The invention provides a NiS@C nanocomposite material for a negative electrode of a battery and a preparation method of the NiS@C nanocomposite material. The preparation method comprises the following steps: with nickel chloride hexahydrate and thiourea as reactive raw materials, producing NiS by a solvothermal method, then coating the surface of the NiS with carbon by a hydrothermal method, and annealing at high temperature to obtain the NiS@C nanocomposite material. The surface of metal sulfide is coated with the carbon, so that the defects that the sulfide has poor cyclicity and stability can be effectively made up, the cyclicity and the stability of the material are improved, and the conductivity of the material can be improved. As a negative electrode material of a lithium-ion battery, the NiS@C nanocomposite material prepared with the preparation method provided by the invention has relatively good lithium battery performance, relatively high specific capacity and relatively good cycling performance.