Performance of Sn-Cu Alloy Anode at Low Temperature

摘要

Sn-Cu alloy anode was prepared by pulsed electrodeposition for lithium ion batteries, and its electrochemical per-formance was tested at low temperature. When temperature decreased from 25°C to -20°C, the Sn-Cu alloyanode provided the capacity retentions of 76% in the electrolyte of 1 mol/L LiBF4/EC+EMC+7BL and 51% inthe electrolyte of 1 mol/L LiPF6/EC+DMC+DEC. Under the same conditions, the graphite anode presented thecapacity retentions of only 41% and 18%, respectively. The Sn-Cu alloy anode showed better performance in theelectrolyte of 1 mol/L LiBF4/EC+EMC+7BL than in the electrolyte of 1 mol/L LiPF6/EC+DMC+DEC, and keptmuch higher capacity retention than that of graphite at -20°C. The Sn-Cu alloy anode in the electrolyte of 1 mol/LLiBF4/EC+EMC+γBL (1.1:1, volume ratio) is promising for low temperature application of lithium batteries.