Strategies for fabrication, confinement and performance boost of Li2S in lithium-sulfur, silicon-sulfur & related batteries

Lithium-sulfur (Li-S) batteries based on elemental sulfur cathodes require the use of highly reactive metallic Li or Li alloy anodes in cell constructions. In order to match with safer Li-free anodes, lithium sulfide (Li2S) has been studied as a promising alternative cathode material for lightweight Li and Li-ion batteries. However, intrinsically high electrical resistance, large first charge barrier, dissolution during cycling and polysulfide shuttle limit the electrochemical performance of Li2S. In this review, we discuss various approaches for producing Li2S-based nano- and micron-scale composite particles and standalone electrodes aiming to overcoming such challenges. In addition, we discuss strategies for electrolyte optimizations. Finally, we share our perspective on the gaps between the state-of-the art research demonstrations and the requirements for successful mass-market commercialization.