Li/Cu共掺杂制备长循环寿命镍铁锰基正极材料  

Preparation of NiFeMn-based anode materials with long cycle life by Li/Cu co-doping

作　　者：吴成龙 李荐[1,2] 王利华 陈永志 WU Chenglong;LI Jian;WANG Lihua;CHEN Yongzhi(School of Materials Science and Engineering,Central South University,Changsha 410083,China;Hunan Zhengyuan Institute for Energy Storage Materials and Devices,Changsha 410083,China;College of Energy and Electrical Engineering,Hunan Institute of Science and Technology,Yueyang 414006,China;College of Mechanical Engineering,Hunan Institute of Science and Technology,Yueyang 414006,China)

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]湖南省正源储能材料与器件研究所,湖南长沙410083 [3]湖南理工学院能源与电气工程学院,湖南岳阳414006 [4]湖南理工学院机械工程学院,湖南岳阳414006

出　　处：《中南大学学报(自然科学版)》2025年第3期891-898,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金青年基金资助项目(52205054);2023年度长沙市科技重大专项项目(kh2401022)。

摘　　要：为了探究Li/Cu共掺杂对层状氧化物材料物相组成、微观形貌、成分价态及电化学性能的影响,采用固相法制备了钠离子电池层状氧化物P2相材料。研究结果表明:在高温固相反应过程中,Li/Cu成功掺入材料晶格,P2相具有完整的P63/mmc空间结构,并展现出光滑的六方片状形貌;降低Mn^(3+)含量有效抑制了材料循环过程中的姜-泰勒现象,提高了材料的结构稳定性;P2相材料在电化学性能方面表现出了优异的循环稳定性和倍率性能;在掺杂量x=0.04,电压为2.0~4.2V时,材料在90mA·g^(-1)电流密度下循环200次的容量保持率为95.46%,在900mA·g^(-1)电流密度仍具有92.0mA·h·g^(-1)的放电比容量。设计合适的Li/Cu共掺杂比例可以有效降低材料的电荷转移阻抗R_(ct),进一步提升P2相材料的电化学性能。In order to investigate the effects of Li/Cu co-doping on the physical phase composition,micro-morphology,compositional valence and electrochemical properties of layered oxide materials,P2 phase materials of layered oxides for sodium ion batteries were prepared by solid-phase method.The results show that Li/Cu is successfully doped into the material lattice during the high-temperature solid-phase reaction,and the P2 phase has a complete P63/mmc spatial structure and exhibits a smooth hexagonal lamellar morphology.The reduction of Mn^(3+)content effectively suppresses the Ginger-Taylor phenomenon during the cycling process of the materials and improves the structural stability of the materials.The P2-phase materials also exhibit excellent cycling stability and multiplicity performance in terms of electrochemical properties.At the doping amount x=0.04,the materials have a capacity retention of 95.46% for 200 cycles at 90 mA·g^(-1) current density in the voltage range of 2.0-4.2 V,and still has a discharge specific capacity of 92.0 mA·h·g^(-1) at 900 mA·g^(-1) current density.By designing a suitable Li/Cu co-doping ratio,the charge transfer impedance R_(ct) of the materials can be effectively reduced,which can further enhance the electrochemical performance of the P2 phase materials.

关 键 词：钠离子电池 层状氧化物 P2相 Li/Cu共掺杂 长循环寿命 

分 类 号：TM912.9[电气工程—电力电子与电力传动]