Nanosized Li2S-based cathodes derived from MoS2 for high-energy density Li-S cells and Si-Li2S full cells in carbonate-based electrolyte

Conversion-type lithium-sulfur (Li-S) batteries tend to become the follow-up system for classical Li-ion batteries based on the intercalation principle. However, the practical application of rechargeable Li-S batteries is still counteracted by fast capacity fading and poor cycling stability caused by the major obstacle of these systems: the polysulfide shuttling. Herein, a feasible in cell formation of nanosized Li2S via full lithiation and irreversible decomposition of MoS2 nanoparticles is proposed. The primary advantage of the resulting Mo/Li2S-based cathode is found in the absence of soluble polysulfide species, allowing its operation in carbonate-based electrolytes. By adjusting the operating condition, Li-S cells in carbonate-based electrolyte with an ultrahigh Li2S loading of 10.7 mg cm(-1) demonstrate good cycle stability and a high average areal capacity of 7.5 mA h cm(-2). In order to tackle uncontrollable lithium dendrite formation, our simple-prepared cathode was successfully coupled with a nanostructured silicon anode to fabricate a Li-S full-cell capable to provide a high capacity of approximate to 780 mA h g(-1), based on the sulfur mass. This easy and effective approach for preparing high-load Li2S cathodes will advance progress in the development of sulfur-based battery technology.