Preparation and characterization of SnO–P2O5 glasses as anode materials for lithium secondary batteries

The glass structure, thermal and electrochemical properties of the SnO–P2O5 glasses, prepared by melt–quenching technique, were examined. The glasses showed relatively low glass transition temperatures of about 250 °C and these values were lower than those of the SnO–B2O3 and SnO–BPO4 glasses. Local structure of the glasses was investigated by Raman and 31P MAS–NMR measurements, suggesting that the number of bridging oxygens decreased whereas the non-bridging oxygen concentration increased with increasing SnO content in the glasses. The electrochemical properties of the glasses as anode materials for lithium secondary batteries were examined using the cells with conventional liquid electrolytes. The cell using the 67SnO · 33P2O5 (mol%) glass as a working electrode exhibited an excellent cycling performance and retained high charge–discharge capacities over 400 mA h g−1 for 20 cycles under a cut-off voltage of 0–0.8 V.