Synthesis and Electrochemical Characterization of LiNi_0.5Co_0.2Mn_0.3O₂ Cathode Material by Solid-Phase Reaction

Abstract

In this paper, using four carbonates as raw materials, the cathode material LiNi0.5Co0.2Mn0.3O2 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 LiNi0.5Co0.2Mn0.3O2 cathode. The results show that 900~1000 °C is the appropriate synthesis temperature range. LiNi0.5Co0.2Mn0.3O2 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.

Keywords

• solid-phase synthesis
• carbonate
• temperature
• LiNi_0.5Co_0.2Mn_0.3O₂