Evaluation of Composite Helices Used as Anodes for Rechargeable Lithium Ion Batteries

Films with helices made of various Cu-Si atomic ratios (10-90%, 20-80%, 30-70%) were fabricated by an ion-assisted glancing angle co-deposition technique. The effect of Cu/Si atomic ratios on the morphologies and the structures were studied by SEM and XRD. The use of those helices as anode materials in lithium ion batteries were evaluated by galvanostatic test results.

The SEM analyses demonstrated that during the co-evaporation an increase in Cu/Si atomic ratio decreased the thickness of the helices, increased the tilting angle and decreased the homogeneity in the thin film morphology. The best performance was achieved when 20%at. Cu containing SiCu helical shaped thin film is used as anode material.

Keywords: Anode, thin film, helices, ion assisted glancing angle depositon, electron beam.