Positive pole material of lithium ion battery with nanometer structure and preparation method thereof

Abstract

The invention discloses a positive pole material of a lithium ion battery with a nanometer structure and a preparation method thereof. The positive pole material is in a particle type core-shell structure, a core material consists of nanometer lithium iron phosphate, lithium vanadium phosphate or cobalt lithium oxide and graphene, and a shell material is porous carbon. The preparation method comprises the following steps of: taking lithium acetate, lithium oxalate, ammonium dihydrogen phosphate, ammonia metavanadate, phosphoric acid, lithium nitrate, cobalt nitrate and graphite oxide as raw materials, adopting a sol-gel method or a ball milling method to prepare a mixture, presintering the mixture in vacuum to obtain the core material, and mixing, grinding and calcining the core material with an organic carbon source to obtain the positive pole material with the particle type core-shell structure. The positive pole material has the advantages of good conductivity, good circulating performance, high capacity, small and uniform particle size, and simple preparation process and is easy for industrialized production.

Description

technical field [0001] The invention relates to a lithium-ion battery cathode material with a nanostructure and a preparation method thereof, belonging to the lithium-ion battery electrode material and preparation technology thereof. Background technique [0002] Lithium-ion secondary batteries have the advantages of high energy density, long cycle life and small self-discharge. Since the first commercial battery was born in 1990, lithium-ion batteries have been widely used in various portable electronic products and mobile devices. At present, in order to meet the market demand for power sources of electric vehicles and hybrid vehicles, lithium-ion batteries with high power density have become a research hotspot. The cathode material of a lithium-ion battery is an important part of the battery, and the performance of the cathode material restricts the power and energy density of the lithium-ion battery. The kinetic process of lithium ion intercalation and deintercalation i...

AI Technical Summary

Problems solved by technology

Although LiCoO 2 The cathode material with this structure has achieved commercial success, but it has two major disadvantages: first, the metal cobalt is not only expensive but also toxic; second, only half of the lithium ions are circulating due to safety concerns. de-embedding and embedding

LiFePO with core-shell structure was synthesized by in situ polymerization method by Wang et al. 4 / C composite material has good electrochemical performance, but this core-shell structure covers lithium iron phosphate with carbon materials, which cannot solve the problem of poor electrical conductivity inside lithium iron phosphate, and there is also a charge-discharge reversibility Problems such as poor performance and poor conductivity