Reversible lithium storage in LiF/Ti nanocomposites

Abstract

Storage and transport behaviors of lithium in LiF/Ti nanocomposites, either formed in situ through a conversion reaction from TiF₃ powder electrode or prepared by the pulse laser deposition method, have been investigated. Reversible lithium storage in the LiF/Ti nanocomposites shows a sloped voltage profile. The lithium storage capacity in the LiF/Ti nanocomposite thin film is much higher than that in single Ti or LiF thin film with the same thickness and is increased with increasing film thickness. Accordingly, lithium should store at the grain boundary regions since either the LiF or the Ti phase is not active for lithium storage. Hence, this type of interfacial storage is intermediate between the insertion and storage in supercapacitors. The transport properties of electrons and lithium ions in initial LiF/Ti nanocomposites are also investigated by IV, IS and blocking electrode techniques.