Influence upon cycling of oxygen amount in tin-based compound used as negative electrode in lithium-ion battery

摘要

Electrochemical and physicochemical characteristics of three tin-based materials with various oxygen amount used as negative electrode in lithium-ion battery have been evaluated and compared. Nanosizing structuration impact in case of SnO2 is also discussed. Depending on the oxygen amount in those materials used as electrode, energy and power density of lithium-ion battery can be modulated up to 2000 Wh/kg and 8000 W/kg for a maximum sustainable 3C rate. Fading depends mainly on the oxygen amount and, to a lesser extent, on nanostructuration. SnO appears as the best candidate in this material family concerning irreversible capacities and coulombic efficiency. Post-mortem characterizations after 100 cycles by XRD, SEM and EDX highlight a lower aggregation of tin particles for oxygen-based materials upon cycles and formation of alpha crystallographic tin phase which can be supposed as beneficial for coulombic efficiency.