Preparation of electrochemically active lithium sulfide–carbon composites using spark-plasma-sintering process

Electrochemically active lithium sulfide–carbon (Li2S–C) composite positive electrodes, applicable for rechargeable lithium-ion batteries, were prepared using spark-plasma-sintering (SPS) process. The electrochemical tests demonstrated that the SPS-treated Li2S–C composites showed the initial charge and discharge capacities of ca. 1200 and 200 mAh g−1, respectively, though Li2S has been reported to show no significant charge capacities when conventionally mixed with carbon powder. Such activation of Li2S was attributed principally to strong bindings between Li2S and carbon powders, formed by the SPS treatment. The ex situ XRD measurements showed that some amounts of Li2S were still remained unchanged and any elemental sulfur was not detected even at fully charged state, which was similar to Li/S cells.