Synthesis and Electrochemical Characterizations of Concentration-Gradient Structure Nickel-Rich Cathode Materials

A nickel-rich cathode material with a continuous concentration-gradient structure of LiNi0.9Co0.05Mn0.05O2 (CG-LNCMO) was successfully synthesized via a two-step co-precipitation process. According to careful examinations conducted via scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) and inductively coupled plasma-optical emission spectroscopy (ICP-OES), CG-LNCMO material has the primary particles with different chemical compositions from the surface to the core of the secondary particles. Moreover, CG-LNCMO has better electrochemical characteristics, as a result of a higher manganese content on the surface of the material, which serves to stabilize the material structure and reduce the side reactions between the material and electrolyte. Compared with the average composition of LiNi0.9Co0.05Mn0.05O2 (AC-LNCMO), the concentration -gradient cathode material has the structural stability, high capacity, and good electrochemical performances to make it a plausible candidate for application in high-performance lithium-ion batteries.