Optimizing conditions and improved electrochemical performance of layered LiNi1/3Co1/3Mn1/3O2 cathode material for Li-ion batteries

Abstract

Herein, we have explored performance of layered LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM111) cathode material for Li ion battery applications, prepared by different preparation strategies namely co-precipitated mixed hydroxide and solid state high temperature approach combined with high-temperature calcination. The effect of crystal structure and morphology of the obtained materials were characterized by means of X-ray diffraction and scanning electron microscopy. X-ray analysis reveals that the observed lattice parameter ratio c/a is greater than 4.89 for materials with different approaches, which indicates the formation of hexagonal layered α-NaFeO 2 structure. The electrochemical properties of the materials were thoroughly characterized by means of charge-discharge experiments and electrochemical impedance spectroscopy. The direct solid state synthesized NCM111 material exhibits a low retention and discharge capacity of 60 mAh g −1 at the end of 50 cycles with high irreversible capacity during cycling. The present studies have shown that the importance of material synthesis route and its sintering process, prepared at 900 °C for 8 h results low cation mixing between Li and metal ions layer in NCM111 lattice compared to other sintered samples, resulting in superior electrochemical performance. The reversible capacity of 175 mAh g −1 is noticed at C/10 rate within the voltage window of 2.5-4.4 V for 900 °C treated sample. Even at C/3 rate, a stable high reversible capacity of 145 mAh g −1 is obtained with high capacity retention of 95%. The Rietveld and EIS spectroscopic analysis conforms the existence stable layered structure and electrode, interface for NCM11 approached through co-precipitation.

Hierarchical α-MnO2nanowires as an efficient anode material for rechargeable lithium-ion batteries

“…Page 12 of 30 Materials Advances axis intercept (at x-axis) in the high-frequency region is ascribed to Ohmic electrolyte resistance (R s ), which essentially comes from the electrolyte, electrodes, etc. [61,11] The middle-frequency region semicircle corresponds to the interface contact and the charge transfer resistance, R ct . [62,63] A spike in the low-frequency region imputes to mass-transfer resistance.…”