Synthesis and Characterization of LiNiCoMnO as Cathode Materials for Li-Ion Batteries via an Efficacious Sol-Gel Method

作者：Xiaoyu Cao, Yang Zhao, Limin Zhu, Lingling Xie, Xiaoli Cao, Shaoyi Xiong, Chi-Wei Wang · 发表于：International Journal of Electrochemical Science · 年份：2016 · DOI：10.20964/2016.06.93 · 被引用次数：37 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Extraction and Separation Processes

A series of LiNi 1/3 Co 1/3 Mn 1/3 O 2 powders have been successfully prepared as cathode materials for lithium-ion batteries by a citric acid-assisted sol-gel method. The crystal structures and microstructures of as-prepared cathode materials were characterized by X-ray diffraction and scanning electron microscopy. Charge/discharge cycling and cyclic voltammetry were also employed to investigate their electrochemical behaviors. X-ray diffraction results show that calcinations temperature and time have the important effects on the crystal structure of LiNi 1/3 Co 1/3 Mn 1/3 O 2 powders. Among all the LiNi 1/3 Co 1/3 Mn 1/3 O 2 powders, the LiNi 1/3 Co 1/3 Mn 1/3 O 2 powder calcined at 850 o C for 16 h demonstrates a phase-pure hexagonal lattice with the best ordered layered structure. Scanning electron microscopy with element mapping tests reveal that the homogeneous LiNi 1/3 Co 1/3 Mn 1/3 O 2 solid solution has been achieved via this synthesis method. The LiNi 1/3 Co 1/3 Mn 1/3 O 2 powder heated at 850 o C for 16 h can deliver a high initial discharge capacity of 199.9 mAh g −1 and still retain the discharge capacity of 143.6 mAh g −1 after 80 cycles at the current rate of 20 mA g −1 in the voltage range of 2.5−4.6 V. Cyclic voltammetry results confirm that as-obtained LiNi 1/3 Co 1/3 Mn 1/3 O 2 powder at 850 o C for 16 h displays the decreased electrode polarization and stable crystal structure upon cycling.