Electrochemical performance of lithium-sulfur batteries based on a sulfur cathode obtained by H₂S gas treatment of a lithium salt

A new technique to produce Li₂S/C composites and Li₂S cathodes as well as their application in high-capacity Li-S batteries is demonstrated. The simple but effective method converts an easy-to-handle lithium salt-containing composite or electrode to Li₂S using H₂S. The main advantage is that the conversion to Li₂S can be performed towards the final stage of the electrode preparation process, which significantly reduces the need of controlled atmosphere otherwise required for Li₂S handling. LiOH is used to demonstrate the technique, and such fabricated Li₂S electrode is successfully used in a Li-S battery (half-cell) where it shows discharge capacities of up to 770 mAh g^-1_(Li2S) and retained >410 mAh g^-1_(Li2S) after 100 cycles at C/5.