Synthesis and Electrochemical Characterization of LiNi0.5 Co0.2 Mn0.3 O2 Cathode Material by Solid-Phase Reaction

Abstract

In this paper, using four carbonates as raw materials, the cathode material LiNi0.5 Co0.2 Mn0.3 O2 was prepared with the “ball milling-calcining” solid-phase synthesis method. The specific reaction process, which consists of the decomposition of the raw materials and the generation of target products, was investigated thoroughly using the TG-DSC technique. XRD, SEM and charge/discharge test methods were utilized to explore the influence of different sintering temperatures on the structure, morphology and electrochemical performance of the LiNi0.5 Co0.2 Mn0.3 O2 cathode. The results show that 900~1000◦ C is the appropriate synthesis temperature range. LiNi0.5 Co0.2 Mn0.3 O2 synthesized at 1000◦ C delivers optimal cycling stability at 0.5 C. Meanwhile, its initial discharge specific capacity and coulomb efficiency reached 167.2 mAh g−1 and 97.89%, respectively. In addition, the high-rate performance of the cathode sample prepared at 900◦ C is particularly noteworthy. Cycling at 0.5 C, 1 C, 1.5 C and 2 C, the corresponding discharge specific capacity of the sample exhibited 148.1 mAh g−1, 143.1 mAh g−1, 140 mAh g−1 and 138.9 mAh g−1, respectively.