Li1.2Ni0.13Co0.13Mn0.54O2 with Controllable Morphology and Size for High Performance Lithium-Ion Batteries.

Abstract

The controllable morphology and size Li-rich Mn-based layered oxide Li1.2Ni0.13Co0.13Mn0.54O2 with micro/nano structure is successfully prepared through a simple coprecipitation route followed by subsequent annealing treatment process. By rationally regulating and controlling the volume ratio of ethylene glycol (EG) in hydroalcoholic solution, the morphology and size of the final products can be reasonably designed and tailored from rod-like to olive-like, and further evolved into shuttle-like with the assistance of surfactant. Further, the structures and electrochemical properties of the Li-rich layered oxide with various morphology and size are systematically investigated. The galvanostatic testing demonstrates that the electrochemical performances of lithium ion batteries (LIBs) are highly dependent on the morphology and size of Li1.2Ni0.13Co0.13Mn0.54O2 cathode materials. In particular, the olive-like morphology cathode material with suitable size exhibits much better electrochemical performances compared with the other two cathode materials in terms of initial reversible capacity (297.0 mAh g-1) and cycle performance (95.4% capacity retention after 100 cycles at 0.5 C), as well as rate capacity (142.8 mAh g-1 at 10 C). The excellent electrochemical performances of the as-prepared materials could be related to the synergistic effect of well-regulated morphology and appropriate size as well as their micro/nano structure.