Sn–Ni/MWCNT nanocomposite negative electrodes for Li-ion batteries: The effect of Sn:Ni molar ratio

Abstract

Since Ni is used to behave as a buffer component in the Sn-based anode materials for the Li-ion batteries, it is aimed to reveal the optimum Sn:Ni ratio to reduce the electrode pulverization emanated from volume increase during the charge/discharge process. MWCNTs were also co-deposited from the suspended MWCNT in the electrolyte to increase buffering effect and conductivity. To reduce irreversible capacity and improve cycle performance of tin electrodes, Sn–Ni/MWCNT three components nanocomposite electrodes were prepared with different Sn:Ni ratio by pulse electrodeposition method using copper substrate as current collector. The morphology and the structures of the Sn–Ni/MWCNT nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD). Raman spectroscopy was used to determine the existence of MWCNT in the Sn–Ni matrix. The electrochemical performance of Sn–Ni/MWNT nanocomposites studied by charge/discharge tests and cyclic voltammetry experiments. Results showed that increasing the amount of co-deposited Ni has a strong effect on the electrochemical performances. The best electrochemical results were obtained in the nanocomposite electrodes with Ni content of 29 wt.%