Optimization of carbon coating thickness to prevent crack generation in Sn nanoparticles during charge/discharge process and their electrochemical properties

One of the drawback of Tin (Sn) as anode material for Li-ion batteries (LIBs) is severe capacity fading due to pulverization of Sn particles during cycling. Many researchers have tried to solve this problem through various carbon coating on the surface of Sn particles. In this work, Sn/Carbon nanoparticles having various carbon coating thicknesses (0.0–7.0 nm) on the surface of Sn nanoparticles was fabricated by using pulsed wire explosion within various alcohol-based liquid media. The optimum carbon coating thickness needed to prevent crack of Sn nanoparticles was investigated. It was also investigated on when the cracks occurred during cycling using electrochemical analysis and acoustic emission signal analysis. It was found that around 95% of the crack is detected in the first cycling and the appropriate thickness of the carbon layer for the crack suppression is more than 5 nm.