Controlling surface morphology of Sn thin-film to enhance cycling performance in lithium ion batteries

With a high Li storage capacity, Sn-based materials have attracted great attention as a prospective anode material for lithium ion batteries (LIBs). However, the poor cycling performance due to repetitive volume expansion/contraction during charge/discharge cycles has restricted the practical application of Sn-based materials. Here, a simple technique of controlling the surface morphology of Sn thin-film by modulating sputtering conditions was proposed to enhance the cycling performance of LIBs. Firstly, the dependence of surface morphology of Sn thin-film on sputtering conditions was systematically investigated. Secondly, variations in the cycling performance of these Sn thin-films were evaluated. Finally, insertion of Cu buffer between the Sn thin-film anode and the Cu foil current collector was proposed to induce particle refinement and therefore enhance the cycling performance. Such a concept can be extended to Si anode and be further combined with other methods to effectively improve the cycling performance of thin-film anode for LIBs. (C) 2016 Elsevier Ltd. All rights reserved.