The codeposition of lithium and silicon was investigated from 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) amide ([Py-1,Py-4]TFSA)at temperatures >= 100 degrees C. Furthermore, electrodeposition of lithium was studied from the same liquid at >= 100 degrees C. Two different sources of Si(IV) (e.g. either SiCl4 or SiBr4) and LiTFSA as a source for Li+ ions were used. Cyclic voltammetry was employed to study the electrochemical behavior of (SiCl4+LiTFSA)/[Py-1,Py-4]TFSA and (SiBr4+LiTFSA)/[Py-1,Py-4]TFSA. The electrodeposited films were characterized using Scanning Electron Microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. SiBr4 was found to be suitable to obtain Li-Si alloys from the mentioned IL. Nanocrystalline lithium was obtained with an average grain size of 30 to 40 nm. XRD analysis of the annealed deposits revealed the formation Li-Si alloys. XPS analysis of the deposit obtained from (SiBr4+ LiTFSA)/[Py-1,Py-4]TFSA indicated the presence of fluoride and oxide of lithium besides metallic lithium. (C) 2018 The Electrochemical Society.