The insertion of Li into layered  sulfides has been reinvestigated with ethylene-carbonate-based carbonate electrolytes. The  and  redox couples in a sulfide were found to give a reversible insertion reaction at about 0.5 and 1.0 V vs , respectively, while Cr atoms are displaced from  at 0.9 V vs . Comparison to a graphite anode indicates that a solid-electrolyte-interface (SEI) passivation layer is formed below 0.9 V during the first discharge of the  before reaching the  redox couple, while an SEI layer was formed after reaching the  redox couple at 1.0 V during the first discharge of the  electrode. The formation of a suitable SEI layer and therefore the reversibility and capacity of sulfide anodes are shown to depend on the composition of the electrolyte.