三元锂离子正极材料LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)的控制合成与储能特性  

Controlled synthesis and energy storage characteristics of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) ternarylithium ion cathode material

作　　者：唐松章 张勇[1,2] 陈鑫洪 舒霞 秦永强[1,2] 吴玉程 TANG Songzhang;ZHANG Yong;CHEN Xinhong;SHU Xia;QIN Yongqiang;WU Yucheng(School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,Anhui,China;Key Laboratory of Advanced Functional Materials and Devices of Anhui Province,Hefei 230009,Anhui,China)

机构地区：[1]合肥工业大学材料科学与工程学院,安徽合肥230009 [2]先进功能材料与器件安徽省重点实验室,安徽合肥230009

出　　处：《金属功能材料》2021年第5期1-6,共6页Metallic Functional Materials

基　　金：国家自然科学基金项目(51672065);安徽省其他地市科技资助项目(JZ2020YDZJ0122)。

摘　　要：采用草酸共沉淀法和高温固相法相结合的方法成功合成了LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)三元锂离子正极材料,通过先用水热合成草酸钴锰前驱体,然后再与镍盐、锂盐进行高温固相反应,避免了Ni^(2+)、Co^(2+)、Mn^(2+)在草酸中沉淀不均匀的问题。X射线衍射(XRD)分析结果表明,该材料具有典型的类似α-NaFeO_(2)的层状结构以及低的阳离子混排。电化学性能测试结果显示,相比于商业镍钴锰酸锂(NCM-商业),NCM622表现出优良的循环稳定性和倍率性能,在0.1C下经850℃处理的NCM-850试样的初始放电容量为184.1mAhg^(-1),高于NCM-商业的175mAhg^(-1),在0.2C循环100圈以后NCM-850的容量保持率为88.6%而NCM-商业的保持率仅为47.8%。在5C下NCM-850仍然具有98.1mAhg^(-1)的容量。这主要归因于材料拥有更稳定的晶体结构和更宽的离子扩散通道。The LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM)ternary lithium ion cathode material was successfully synthesized by the combination of oxalic acid co-precipitation method and high temperature solid phase method.The cobalt manganese oxalate precursor was synthesized by hydrothermal method first,and then high temperature solid-phase reaction with nickel salt and lithium salt avoided the problem of uneven precipitation of Ni^(2+),Co^(2+)and Mn^(2+)in oxalic acid.X-ray diffraction analysis(XRD)results showed that the material had a typicalα-NaFeO_(2)-like layered structure and low cation mixing.Electrochemical performance test results showed that compared to commercial lithium nickel cobalt manganese oxide(NCM-commercial),NCM622 exhibited excellent cycle stability and rate performance.The initial discharge capacity of NCM-850 samples treated at 850℃at 0.1 C,was 184.1 mAh g^(-1) while NCM-commercial was only 175 mAh g^(-1).After 100 cycles of 0.2 C,the capacity retention rate of NCM-850 was 88.6%while that of the retention rate of NCM-commercial was only 47.8%,at 5 C,NCM-850 still had a capacity of 98.1 mAh g^(-1).This was mainly due to the material having a more stable crystal structure and larger ion diffusion channels.

关 键 词：LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) 锂离子电池 正极材料 共沉淀法 高温固相法 

分 类 号：TQ131.11[化学工程—无机化工] TM912[电气工程—电力电子与电力传动]