Preparation and Characterization of SnO-Based Glasses as Anode Materials for Lithium Secondary Batteries.

Abstract

Glasses in the systems of Li₂O-SnO-B₂O₃ and Li₂O-SnO-BPO₄ were prepared by a melt quenching method and their thermal, viscous, and electrochemical properties were investigated. The SnO based glasses exhibited the relatively low glass transition temperatures (T_g) of ≈350°C and an excellent thermal stability against crystallization. The values of T_g and E_η/T_g, where E_ηis the activation energy for viscous flow at around T_g and E_η/T_g is the fragility parameter, were maximized at around a composition of 40mol% SnO in the SnO-B₂O₃ system. The electrochemical properties of those glasses were investigated by using a simple three-electrode cell with the glass as a working electrode, lithium sheets as both counter and reference electrodes, and 1M LiPF₆/EC+DEC as a liquid electrolyte. The SnO based glasses worked as anode materials with high discharge capacities over 650mAh·g^-1 at the first cycle and exhibited good cycling performance.