Electrochemical study of NiO nanoparticles electrode for application in rechargeable lithium-ion batteries

Nickel oxide nanoparticles were synthesized via a simple and inexpensive microwave-assisted synthesis method within a fast reaction time of less than 20 min. The calcination of as-prepared precursor at 600 °C produces single phase nickel oxide. The lattice structure and morphology of the sample were investigated by X-ray diffraction, field-emission scanning electron microscopy and field-emission transmission electron microscopy. The particle size range of the nickel oxide nanoparticles varied from 50 to 60 nm. Nickel oxide nanoparticles exhibited good electrochemical performances as an anode material for lithium-ion batteries. The prepared nickel oxide anode revealed a large initial discharge capacity of 1111.08 mAh g−1 at 0.03 C rate and retained 80% of initial capacity (884.30 mAh g−1) after 20 cycles. Furthermore, at elevated rate of 3.7 C, the charge capacity of the nickel oxide electrode was as high as 253.1 mAh g−1, which was 35% greater than that of commercial bulk nickel oxide (188 mAh g−1). The enhancement of the electrochemical performance was attributed to the high specific surface area, good electric contact among the particles and easier lithium ion diffusion.