Electrochemical performance of Cu(6)Sn(5) alloy anode materials for lithium-ion batteries fabricated by controlled electrodeposition.

Combining electrodeposition and heat treatment is an effective method to successfully fabricate Cu(6)Sn(5) alloy materials, in which the S2 alloy electrode is electrodeposited at 1.2 A dm(-2) current density with uniform and compact morphology. The characterization results show that monoclinic η'-Cu(6)Sn(5) and hexagonal η-Cu(6)Sn(5) phases fabricated at the appropriate current density exhibit excellent electrochemical performance. The optimal Cu(6)Sn(5) alloy anode material boasts not just a significantly high discharge specific capacity of 890.2 mA h g(-1) with an initial coulombic efficiency (ICE) of 73.96%, but also achieves an adequate discharge specific capacity of 287.1 after 50 cycles at 100 mA h g(-1). Moreover, the electrodeposited Cu(6)Sn(5) alloy materials also possessed a lower transfer resistance of 42.45 Ω and an improved lithium-ion diffusion coefficient of 2.665 × 10(-15) cm(2) s(-1) at the current density of 1.2 A dm(-2). Therefore, preparing the Cu(6)Sn(5) alloy thin-film electrode could be a cost-effective and straightforward method by electrodeposition from cyanide-free plating baths to develop anode components suitable for lithium-ion battery applications.