富镍三元正极材料的研究进展  

Research progress of Ni-rich ternary cathode materials

作　　者：郭学益 蔡海燕 毛高强 喻万景 童汇 訚硕 GUO Xueyi;CAI Haiyan;MAO Gaoqiang;YU Wanjing;TONG Hui;YIN Shuo(School of Metallurgy and Environment,Central South University,Changsha 410083,China;National&Regional Joint Engineering Research Center of Nonferrous Metal Resources Recycling,Changsha 410083,China;CNGR Advanced Material Co.,Ltd.,Tongren 554300,China)

机构地区：[1]中南大学冶金与环境学院,长沙410083 [2]有色金属资源循环利用国家地方联合工程研究中心,长沙410083 [3]中伟新材料股份有限公司,铜仁554300

出　　处：《工程科学学报》2025年第4期697-716,共20页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(52227806);长沙市重大科技攻关项目(kh2301024);中南大学前沿交叉项目(2023QYJC027)。

摘　　要：富镍三元正极材料(LiNi_(x)Co_(y)Mn_(2)O_(2),x≥0.8)具有高能量密度、长循环寿命、低成本及绿色环保等优势,被认为是目前最具发展潜力的锂离子电池正极材料之一,特别在电动汽车和可再生能源储存系统中有着广阔的应用前景.然而,随着镍含量不断提高,富镍三元正极材料在结构及界面稳定性、循环和安全性能等方面面临诸多挑战,严重制约了其大规模产业化应用.鉴于此,本文首先综述了富镍三元正极材料目前面临的各种挑战,包括锂镍混排与不可逆相变、表面残碱与界面副反应、应力应变与微裂纹及过渡金属溶解等问题,并对其形成的原因、存在的危害以及演变的过程进行了详细的阐述.随后针对上述存在的各种问题,系统总结了富镍三元正极材料主要的改性策略,包括离子掺杂、表界面修饰、单晶化结构设计、浓度梯度和核壳结构设计等,旨在提高材料的整体性能.最后,针对富镍三元正极材料的未来发展方向进行了展望.本文为富镍三元正极材料的研究提供全面总结和分析,为高比能长循环高安全富镍三元正极材料的设计开发和实践应用提供参考.Ni-rich ternary cathode materials(LiNi_(x)Co_(y)Mn_(2)O_(2),x≥0.8)have significant potential for use in lithium-ion batteries because of advantages that include their high energy density,long cycle life,low cost,and environmental sustainability.In particular,they have great application prospects in electric vehicles and renewable energy storage systems.However,with an increase in Ni content,materials face numerous challenges in terms of their structural and interfacial stability,cycling,and safety.The fundamental reason for these issues is the hybridization of the 3d orbitals of transition metals with the 2p orbitals of oxygen.During the charge and discharge processes,the oxidation state of transition metals such as Ni varies between+2 and+4 valences,and hole states are spontaneously generated at the O 2p energy level.The density of the hole states in the O 2p orbitals increases with the state of charge(SOC),ultimately leading to the release of lattice oxygen.With this increase in the amount of released lattice oxygen,layered phases transition to spinel or rock salt phases,which affect the electrochemical activity of the material.In addition,the H2-H3 phase transition at approximately 4.2 V can lead to intergranular slip and the formation of intergranular microcracks.These exacerbate the harmful reactions at the cathode-electrolyte interface,leading to a significant decrease in cycling stability.These issues become even more serious if the Ni content is greater than 90%,which seriously restricts its large-scale industrialized application.This paper first reviews the various challenges currently faced by Ni-rich ternary cathode materials,including lithium-nickel mixing and irreversible phase transitions,surface residual alkali and interfacial side reactions,stress-strain and microcracking,and transition metal dissolution.Furthermore,a comprehensive analysis of the causes,associated hazards,and evolution of these issues is provided.Subsequently,the main modification strategies for Ni-rich ternary cathode material

关 键 词：锂离子电池 富镍三元正极材料 失效机制 离子掺杂 界面修饰 结构设计 

分 类 号：TQ152[化学工程—电化学工业]