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

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 (Tg) of ≈350°C and an excellent thermal stability against crystallization. The values of Tg and Eη/Tg, where Eηis the activation energy for viscous flow at around Tg and Eη/Tg 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.