富镍三元层状过渡金属氧化物正极材料的改性方法研究综述

富镍三元层状过渡金属氧化物正极材料因具有比容量高、价格低廉以及对环境友好等特性而备受关注,但受锂镍混排、相变反应、产气、微裂纹、过渡金属溶出、表面结构等影响,材料本身存在循环容量衰减等问题。针对正极材料循环容量衰减过快、高温性能不佳等问题,总结了近年来国内外关于富镍三元层状过渡金属氧化物正极材料的改性方法,包括表面包覆材料合成、元素掺杂材料制备、核壳结构材料开发、浓度梯度材料设计等优化方法,指出高镍层状过渡金属氧化物正极材料的应用需要从不断完善材料制备方法、改变材料性状、降低材料成本等方面入手,开发高能量密度的锂离子电池,使富镍三元层状过渡金属氧化物正极材料在动力电池领域尽早得到广泛应用。

Research summary of modification of nickel-rich ternary layered transition metal oxides positive materials

Nickel-rich ternary layered transition metal oxide positive materials have attracted much attention due to their high specific capacity, low price and environmental friendliness. However, the material itself has problems such as cyclic capacity degradation, which are caused by Li/Ni mixing, phase change reaction, gas generation, microcracks, transition metal dissolution and surface structure changes. In order to solve the problems of rapid capacity degradation and poor high-temperature performance of positive materials, modification methods of nickel-rich ternary layered transition metal oxide positive materials at home and abroad in recent years were summarized, including optimization methods such as surface coating material synthesis, element doping material preparation, core-shell structure material development, and concentration gradient material design, etc. It is pointed out that the wide application of high nickel layered transition metal oxide anode materials needs to start from the aspects of continuously improving the material preparation method, changing the material properties, and reducing the material cost, etc. to develop high energy density lithium ion batteries, so that nickel-rich ternary layered transition metal oxide anode materials can be applied in the field of power batteries as soon as possible.