Electrodeposition of Sn–Cu alloy anodes for lithium batteries

Electrodeposition and heat-treatment was attempted to directly obtain a Sn–Cu alloy anode with fine grain of crystals for lithium ion batteries. The preparation of Sn–Cu alloy anode started with pulsed electrochemically depositing tin on the substrate of copper foil collector, and a protection coating layer of copper was plated on the surface of deposited Sn. An alloy of tin and copper was formed when heated. The energy dispersive spectroscope (EDS) and X-ray diffraction (XRD) analysis showed the copper and tin were partially alloyed to form Cu6Sn5 and Cu3Sn after annealing. The SEM analysis showed the uncoated electrode is cracked after a cycle and the copper coated electrode was not cracked after 50 cycles. The Cu-coated electrode presented the first cycle coulomb efficiency reaching 95% and good cycleability.