Investigating the Mg-Si Binary System via Combinatorial Sputter Deposition As High Energy Density Anodes for Lithium-Ion Batteries

摘要

Mg-Si thin films with various elemental compositions ranging from 0 <= x <= 1 in MgxSi((1-x)) were obtained via combinatorial magnetron sputter deposition of Si and Mg in order to improve the electrochemical lithiation/ delithiation process of pure Si by embedding Si in an active Mg Si matrix. Scanning electron microscopy, energydispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy methods were used to investigate the morphology, stoichiometry, and structure of the different thin film samples. Constant current charge/discharge cycling revealed significant electrochemical changes depending on the Mg content in comparison to the pure Si active material improving the capacity retention to 96% over 400 cycles.