富镍三元正极材料的改性研究进展  

Research Progress in the Modification of Nickel-rich Cathode Materials

作　　者：郭孝东[1] 徐春柳 向伟[1] 吴振国[1] 钟本和[1] GUO Xiaodong;XU Chunliu;XIANG Wei;WU Zhenguo;ZHONG Benhe(School of Chemical Eng.,Sichuan Univ.,Chengdu 610065)

机构地区：[1]四川大学化学工程学院

出　　处：《工程科学与技术》2020年第1期9-17,共9页Advanced Engineering Sciences

基　　金：国家自然科学基金项目（21878195;21506133)

摘　　要：随着便携式电子产品和电动车领域的高速发展,对高能量密度锂离子电池的性能提出了更高的要求。相比传统的钴酸锂正极材料,富镍层状金属氧化物具有较高能量密度和较低的原料成本,被视为理想的锂离子电池正极材料。然而,其结构缺陷和不稳定的界面化学特性会恶化材料的电化学性质、热力学稳定性和安全性能。本文主要回顾了近年来关于富镍三元正极材料的改性研究进展,旨在为今后富镍三元正极材料的设计提供重要思路,并实现其工业化应用。首先,介绍了富镍正极材料本身存在的固有缺陷和电化学性能衰减机制。其次,讨论了通过调控表界面结构提升富镍材料性能的改性策略,包括包覆电化学惰性物质、设计元素全浓度梯度及核壳结构、构筑核壳异质结构和调控包覆物质厚度等。然后,总结了通过元素的体相掺杂提升富镍正极材料性能的策略,包括碱金属位掺杂、过渡金属位掺杂、氧位掺杂和复合共掺杂。最后,对该领域的未来发展进行了总结和展望,希望能激发更多创新性的见解和策略,以促进富镍三元正极材料的实际应用。With the rapid development of portable electronic products and electric vehicles,the performance of lithium ion batteries has been put forward higher requirements.Compared with traditional lithium cobalt oxide cathode materials,nickel-rich layered metal oxides have higher energy density and lower raw material cost,and are considered as ideal cathode materials for lithium-ion batteries.However,its structural defects and unstable surface chemical properties will deteriorate the electrochemical properties,thermodynamic stability and safety performance.This paper reviews the research progress of modification of nickel-rich ternary cathode materials in recent years,aiming at providing important ideas for future design of nickel-rich ternary cathode materials and realizing their industrial application.Firstly,the inherent defects of nickel-rich cathode materials and the degradation mechanism of electrochemical performanceare introduced.Then,the modification strategies to improve the properties of nickel-rich materials by adjusting the interface structure are discussed,including coating electrochemical inert substances,designing element concentration gradient and core-shell structure,constructing core-shell heterostructure and controlling the thickness of the coating materials.After that,the strategies to improve the performance of nickel-rich cathode materials by bulk doping of elements are also summarized,including alkali metal-sites doping,transition metal sites doping,oxygen sites doping and synergy co-doping.Finally,the future development in this field is summarized and prospected,expecting to inspire more innovative ideas and strategies to promote the practical application of nickel-rich cathode materials.

关 键 词：锂离子电池 三元正极 富镍 表面包覆 元素掺杂 

分 类 号：TM912[电气工程—电力电子与电力传动]