A Study of Li-ion Diffusion Kinetics in the Fullerene-Coated Si Anodes of Lithium Ion Batteries

Abstract

The diffusion coefficient of lithium ions in fullerene-coated silicon thin film electrodes, prepared by the plasma-assisted deposition technique, was estimated by a specific electrochemical measurement known as cyclic voltammetry (CV) and then compared with that of a bare silicon film used as the anode in lithium ion batteries. Based on our experimental range, the diffusion coefficient of the fullerene-coated Si thin film was found to be 10−9 cm2 s−1 or two orders of magnitude higher than that of the bare Si thin film ( 1011 cm2 s−1). It can be concluded that the fullerene film acts as an artificial solid electrolyte interphase (SEI) layer during charging–discharging tests.