Synthesis and Electrochemical Performance of Copper-Doped Lini0.8co0.15al0.05o2 for Application in Lithium-Ion Batteries
In this study, synthesis, electrochemical investigation of particles of LiNi0.8Co0.15Al0.05O2 (NCA) and influence of
the doping Cu2+ ion on its structure and properties has been studied. Cu-doped LiNi0.8Co0.15Al0.05O2 cathode material is
prepared by using co-precipitation methods. X-ray diffraction (XRD) results show that the Cu-doped NCA samples are
indexed the αNaFeO2 structure with space group R-3m and no obvious difference in XRD patterns. The morphology and
size of the samples are characterized by scanning electron microscope (SEM) analysis, which show that Cu-doped samples
and are approximately the same as that of the pristine cathode material. The ability of the cathodic materials in Li-ion
batteries are researched with cyclic voltammetry, Electrochemical Impedance Spectroscopy (EIS) and galvanostatic
charge/discharge methods. The Cu doped compound shows excellent electrochemical performance with an initial discharge
capacity of 221.2 mAh g-1 and 185.6 mAh g-1 after 20 cycles at 2 C between 2.5 and 4.5 V with capacity retention of 83%.
The results of EIS demonstrated that Cu2+ doping reduces the charge transfer resistance and facilitates the Li ion diffusion.
Keywords- Li-ion battery; Ni-rich cathode; Doping; Co-precipitation method.