Reversible storage of Li-ion in nano-Si/SnO2 core-shell nanostructured electrode

Abstract

A core-shell nanostructured composite material consisting of nano-Si as the core and SnO2 as the shell is synthesized by a sol-gel method. The reaction mechanism between Li and a nano-Si/SnO2 core-shell nanostructured electrode is investigated, the partial reversible reaction between Li and SnO2 during the first cycle is identified, and the reactivity of the Si core is investigated by ex situ analyses. The nano-Si/SnO2 core-shell nanostructured electrode shows a reversible capacity of ca. 1000 mA h g(-1) and good cycle retention close to 80% of the first charge capacity over 50 cycles.