Ultrafine LiNi1/3Co1/3Mn1/3O2 powders via an enhanced thermal decomposition solid state reaction

摘要

Enhanced thermal decomposition of carbonates is developed to improve the traditional solid state reaction for the synthesis of ultrafine LiNi1/3Co1/3Mn1/3O2 powders. Controllable activation is obtained by optimizing the mechano-chemical treatment time, which is found to affect lattice structure, morphology and electrochemical properties of the as-synthesized ultrafine LiNi1/3Co1/3Mn1/3O2 powders. The optimal mechano-chemical activation time of 10h results in more stable and integrated structured ultrafine LiNi1/3Co1/3Mn1/3O2 powders with average diameter of 200-500nm, leading to a high reversible capacity of 114.3 and 140.9 mAh g(-1) at 6 C (1620mAg(-1)) in the voltage range of 2.5-4.3 and 2.5-4.5V, respectively. Moreover, the particles exhibit capacity retentions of 80.8% (2.5-4.3V) and 83.3% (2.5-4.5V) at 270mAg(-1) after 200 cycles. Importantly, it is revealed that ball-milling has a positive impact on the calcination process, and the decomposition efficiency is about 35.7% higher compared to ball-milling-free process.Graphical abstractThe LiNi1/3Co1/3Mn1/3O2 powders prepared by enhancing thermal decomposition show a remarkable high temperature electrochemical property. For optimum performance, the time of mechano-chemical activation should be neither too long nor too short. In addition, the calcination process is further studied in order to understand the transformation regularities of the electrode materials.