富锂锰基正极材料Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2的Zn^(2+)掺杂改性

Modification of Li-rich Manganese Cathode Material Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2 by Zinc-ion Doping

采用高温固相合成法制备富锂锰基正极材料Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54-x)Zn_xO_2(x=0,0.03,0.06,0.10),Zn^(2+)掺杂对Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2的表面特性和电化学性能都有影响。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、拉曼光谱分析、充放电测试、倍率特性测试、循环性能测试,分析了该合成材料的晶体结构、形貌特征、微观结构和电化学性能。富锂锰基正极材料为a-NaFeO_2层状结构,R-3m空间群,结晶度高,结构稳定性好,其中Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.48)Zn_(0.06)O_2的电化学性能较好。掺杂Zn^(2+)可以提高富锂锰基正极材料的充放电比容量、倍率性能、循环性能等电化学性能。

A series of Li-rich manganese cathode materials Li1. 2 Ni0.13 Co0.13 Mn0.54-xZnxO2 （x=0,0.03,0.06,0.10） synthesized through a high temperature solid state route, and influences of Zn2＋ doping on surface property and electrochemical per- formance of the layered Lil. e Ni0. 13 Co0.13 Mno. 54O2 were studied. X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, Raman spectroscopy, charge-discharge measurements and electrochemical impedance spectroscopy were adopted to analyze and deter- mine the crystal structures, appearance characteristics, microstructures and electrochemical performances of the synthesized catho- des. The as-synthesized Li-rich manganese cathode materials are a-NaFe02 layered structure, which belongs to R-3m space group, with high crystallinity and structural stability. The electrochemical performance of Lil. 2 Ni0.13 Co0.03 Mn0. 48 Zn0. 0- 02 was better than the other cathodes. We proved that Zn^2＋ doping can improve the electrochemical properties of Li-rich manganese cathode material, such as charge and discharge specific capacity, rate performance and cycling performance.