Electrochemical characterization of SnO2/C nanocomposites by conversion reaction for lithium and sodium ion batteries

Abstract

To date, there has been much research on electrochemical study of lithium ion batteries; however, the question has also been raised for depletion of lithium resources, causing interest in sodium ion batteries. While extensive investigations on conversion reactions of various metal oxides as lithium electrode materials have been carried out, conversion reactions in sodium-based systems have been rarely reported. Here we have synthesized spherical SnO2/C core-shell nanoparticles with ~ 70 nm by simple hydrothermal reaction and the electrochemical performance of SnO2/C nanocomposites were tested in both lithium and sodium electrolytes. Ex-situ X-ray diffraction studies were performed in order to investigate the structural changes during electrochemical lithium and sodium conversion reactions. There is a marked contrast between lithium and sodium cells from electrochemical results and XRD data. The comparison study of electrochemical performance in lithium versus sodium system, and structural differences during the conversion reactions will be discussed.