Preparation method of modified nanocarbon coated lithium iron phosphate positive electrode material

The invention discloses a preparation method of a modified nanocarbon-coated lithium iron phosphate positive electrode material, which comprises the following steps: carrying out in-situ coating on a LiFePO4 material through modified nanocarbon powder, improving the conductivity of the prepared LiFePO4 positive electrode material, controlling FePO4 to form a uniform crystal nucleus structure in combination with a complexing agent, reducing the oxidation of iron in the reaction process, and controlling the content of Fe impurities. The agglomeration of the particles is inhibited by phthalimide, stearyl hydrazide and ultrasonic dispersion, and certain growth guiding and optimizing effects are achieved on the coated three-dimensional network structures on the surfaces of the lithium iron phosphate particles. 本发明公开了一种改性纳米碳包覆磷酸铁锂正极材料的制备方法，通过改性纳米碳粉末对LiFePO4材料进行原位包覆，提高制备的LiFePO4正极材料的导电性，结合络合剂控制FePO4形成均一的晶核结构，同时减少反应过程中铁的氧化，控制Fe杂质含量，苯二甲酰亚胺与硬脂酰肼及超声分散抑制颗粒的团聚，对磷酸铁锂颗粒表面的包覆型三维网状结构起到一定的引导生长和优化作用。