Reinvestigation of Li[sub 1−x]Ti[sub y]V[sub 1−y]S[sub 2] Electrodes in Suitable Electrolyte: Highly Improved Electrochemical Properties

Reversible electrochemical intercalation of Li into the dichalcogenides, which was frustrated in the 1970s by the use of in propylene carbonate as the electrolyte, is reinvestigated with in ethylene carbonate:diethyl carbonate (1:1). The choice of the electrolyte allows full electrochemical cycling between and ( or ). The as-prepared samples were fully lithiated after the first discharge, and from a subsequent charge of to , the room-temperature solubility limits of the parent 3S phase, the Li-rich hexagonal phase, the intermediate α and β phases, and the hexagonal Li-poor hexagonal phase have been determined. Introduction of Ti in remarkably improves the capacity at high cycling rates and increases the voltage by about .