微量石墨烯包覆钴酸锂的制备与电化学性能  

Preparation and electrochemical properties of LiCoO2 coated with micro graphene

作　　者：谭洁慧 邓凌峰[1,2] 连晓辉 张淑娴 李金磊 TAN Jie-hui;DENG Ling-feng;LIAN Xiao-hui;ZHANG Shu-xian;LI Jin-ei(School of Materials Sscience and Enginering,Central South University of Forestry and Technology,Changsha Hunan 410004,China;Hunan Xineng New Material Co.,Ltd.,Charngsha Hurian 410205,Chiria)

机构地区：[1]中南林业科技大学材料科学与工程学院,湖南长沙410004 [2]湖南烯能新材料有限公司,湖南长沙410205

出　　处：《电源技术》2020年第10期1412-1416,共5页Chinese Journal of Power Sources

基　　金：国家自然科学基金重点资助项目(31530009);湖南省科研创新资助项目(CX2018B458)。

摘　　要：通过改性Hummers法制备少层氧化石墨烯,取微量氧化石墨烯与高温固相法制得的LiCoO2复合,经高温还原干燥处理形成石墨烯/LiCoO2复合正极材料。实验通过X射线衍射(XRD)、红外光谱(FTIR)、扫描电镜(SEM)、透射电镜(TEM)以及电化学测试等方法,研究材料的结构、形貌和电化学性能。制备的还原氧化石墨烯能有效包覆LiCoO2晶体颗粒团,减少LiCoO2与电解液的直接接触,与LiCoO2颗粒形成三维纳米级导电网络,并显著提高导电性。电化学实验表明:通过石墨烯的包覆,石墨烯/LiCoO2复合材料在0.1 C下,放电比容量达到162.56 mAh/g,并且在1 C下循环100次后,放电比容量由160.2 mAh/g衰减至152.8 mAh/g,而5 C下,石墨烯/LiCoO2复合材料的放电比容量为122.37mAh/g。The modified Hummers method was used to prepare the GO with a few layers.The LiCoO2 prepared by high temperature solid phase method was combined with trace amounts of GO and subjected to high temperature reduction and drying process to form rGO/LiCoO2 composite anode material.The structure and electrochemical properties of the prepared materials were studied by XRD,FTIR,SEM,TEM and electrochemical measurement technologies.The prepared rGO could effectively cover LiCoO2 crystal particles,so it reduced the direct contact between LiCoO2 and electrolyte and formed a three-dimensional nanoscale conductive network,and the electrical conductivity was improved.Electrochemical experiments show that,due to the coating of rGO,the specific discharge capacity of graphene/LiCoO2 composite materials reaches 162.56 mAh/g at the rate of 0.1 C,and the specific discharge capacity decreases from 160.2 mAh/g to 152.8 mAh/g at the rate of 1 C after 100 cycles.When the discharge rate increases to 5 C,the specific discharge capacity of graphene/LiCoO2 composite materials is 122.37 mAh/g.

关 键 词：还原氧化石墨烯 LICOO2 微量包覆 复合材料 电化学性能 

分 类 号：TM912[电气工程—电力电子与电力传动]