55results about How to "Stable cycle life" patented technology

The invention provides a preparation method for carbon-coated nano ferroferric oxide for a battery. The method comprises the following steps: performing dry mixing on ferroferric oxide and conductive carbon black with high purity; adding the ferroferric oxide and conductive carbon black which are subjected to dry mixing into a prepared sodium hydroxide solution; adding a prepared sodium borohydride solution into a reaction solution; aging; cleaning with pure water; dispersing by using ultrasonic waves; filtering; stoving; sieving; and sealing and packaging. An iron nickel battery produced from the carbon-coated nano ferroferric oxide for a battery electrode is high in gram volume, high in charging-discharging efficiency, low in self discharging rate, simple in process, high in strength and long in service life, and can be sealed.

The invention discloses a preparation method of a multilevel structure titanate negative electrode material for a lithium ion battery, and belongs to the technical field of lithium ion batteries. Themethod concretely comprises the following steps: dispersing a sodium source and a titanium source in a glycol and anhydrous ethanol mixed solution to form a solution A; dissolving a barium source in an aqueous solution of anhydrous ethanol to form a solution B; mixing and stirring the solution A and the solution B, heating the obtained solution until evaporative drying is achieved, placing the obtained precursor in a muffle furnace, and carrying out pre-calcining, ball milling and calcining to obtain a BaNa2Ti6O14 material; dispersing the material in an acetone solution, adding carbon nano-tubes, and stirring and heating the obtained solution until the solution is completely volatilized in order to obtain BaNa2Ti6O14-CNT; and carrying out mixing and ball-milling on the BaNa2Ti6O14-CNT andcarbon fibers, and sintering the obtained mixture in nitrogen to obtain the target product. The titanate negative electrode material obtained in the invention has a stable multilevel composite structure, so the titanate negative electrode material has the advantages of considerable wide potential window reversible capacity, excellent rate performances and stable cycle life.

The invention discloses a synchronous control method for a surface structure and a chemical composition of a layered lithium-rich cathode material, wherein the cathode material has the general formulaof xLi2MnO3.(1-x)LiMO2 or Li1+x[M]1-xO2, and M is one or a plurality of Mn, Co, and Ni. The method comprises the steps of: 1) placing a carbonate precursor in a treating agent solution for surface treatment; and 2) burning the treated carbonate precursor into an oxide for uniform mixing with the lithium source compound, and obtaining a surface-modified layered lithium-rich cathode material by high temperature calcination. The main body of the material is of a layered structure with a spinel phase on the surface, a transitional mixed phase is provided between the layered structure and the spinel phase, and the chemical composition of the surface is different from that of the host. The invention has simple and easy operation, and is capable of imparting excellent electrochemical performances such as rapid lithium ion diffusion channel, stable cycle life and weak voltage decay of the positive electrode material.

The present invention provides anodes comprising an electrically conductive substrate, comprising at least one non-uniform surface; and a random network of silicon nanowires (Si NWs) chemically grown on said at least one non-uniform surface of the substrate, wherein the Si NWs have at least about 30% amorphous morphology, and methods of manufacturing of the anodes. Further provided are lithium ion batteries comprising said anodes.