Enhanced electrochemical performance of LiNi0.8Co0.1Mn0.1O2 by surface modification with lithium-active MoO3

Abstract LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode materials coated with MoO 3 were synthesized via drying coating process with low velocity ball milling. The crystal structure and particle morphology of the sample were examined and observed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the surface modification had a little change on the samples and illustrated that the components of the coating layer were MoO 3 /Li 2 MoO 4 . Electrochemical results demonstrated that the MoO 3 coated samples exhibited preeminent electrochemical performance compared with the bare samples. Particularly for the 3 wt% MoO 3 coated samples, its initial coulombic efficiencies increased from 83.3% to 89.0%. Furthermore, the 3 wt% MoO 3 coated samples exhibited the highest capacity retention of 94.8% after 100 cycles at 1 C, and possessed the excellent rate discharge performance at a high current density. The electrochemical impedance spectroscopy and cyclic voltammetric results suggested that the layered MoO 3 coating could suppress the augmenter of the charge transfer resistance and stabilize the active material structure during cyclic process.