3results about How to "Improved cycle rate performance" patented technology

The invention discloses a modified porous silica negative electrode material of a lithium ion battery and a preparation method and application of the modified porous silica negative electrode material, the modified porous silica negative electrode material comprises an inner core layer and a shell layer coating the inner core layer, and the inner core layer is a pre-magnesium silica material, namely porous SiO; the shell layer comprises a carbon nano tube growing on the surface of the porous SiO in situ and a carbon nano tube-nitrogen-doped conductive coating and repairing carbon layer, and the carbon nano tube is embedded in a porous channel of the porous SiO. The modified porous silica negative electrode material is prepared by constructing porous defects on the surface of silicon monoxide, modifying in-situ catalytic growth of carbon nanotubes and doping, coating and repairing a structure; according to the method, the carbon nanotubes can be quickly and uniformly grown on the surface of the porous silica powder and in pore channels, so that firm connection between the inner core layer and the outer shell layer is formed; meanwhile, the electronic conductivity and the ionic conductivity of the material are improved through the point-line-point connection mode. The obtained modified porous silica negative electrode material for the lithium ion battery has relatively high first efficiency, excellent conductivity and cycle rate capability.

The invention discloses a lithium ion battery high-entropy alloy modified silicon-oxygen-carbon composite material as well as a preparation method and application thereof. The innermost layer of the composite material is a multiphase inorganic-organic SiOC material, the middle layer of the composite material is SiOC loaded with a high-entropy alloy, the composite material has a micro-mesoporous structure from inside to outside, and the outermost layer of the composite material is a high-conductivity carbon tube. The composite material prepared by the invention takes an interface as a starting point and takes layer-by-layer superposition as a path to finally generate a shell with a complete structure. By forming a high-entropy alloy modified coating layer which is internally and externally communicated on the surface of SiOC, the ion and electron conductivity can be remarkably improved, more lithium storage active points are provided, heteroatom-doped high-conductivity carbon tubes grow on the catalytic surface, the impedance of the material in the charge-discharge process is reduced, and the cycle rate performance of the material is improved.

This invention discloses a graphite-coated Prussian blue and its analogues, their preparation method, and applications, belonging to the field of graphite material preparation technology. The method includes: mixing graphite with one or more of ferric chloride or transition metal chlorides at a mass ratio of 10-0.5, placing the mixture in a reaction apparatus, and purging the apparatus with a protective gas; heating the reaction apparatus to obtain a solid powder; mixing sodium ferrocyanide with the solid powder at a molar mass ratio of 4-1 and adding it to deionized water, with a solid-to-deionized water mass ratio of 1:50-500, and then stirring the reaction for 12-48 hours; filtering the solution after the reaction. This invention uses a protective gas atmosphere to vaporize ferric chloride or transition metal chlorides at high temperature, allowing the ferric chloride or transition metal to be perfectly incorporated into the interlayer spaces of graphite. Then, the sodium ferrocyanide aqueous solution reacts fully with the ferric chloride or transition metal chloride inside the graphite to obtain a graphite structure completely coated with Prussian blue.