A Novel Lithiated Silicon–Sulfur Battery Exploiting an Optimized Solid-Like Electrolyte to Enhance Safety and Cycle Life

A novel lithiated Si�S battery benefited by an optimized solid-like electrolyte (OSE) is demonstrated, which is fabricated via absorbing 5 wt% fluoroethylene carbonate (FEC) additive and 95 wt% traditional ether-based liquid electrolyte into a SiO2 hollow nanosphere layer. Sulfur or Si particles were incorporated into appropriate carbon matrices (S@CMK-3 mesoporous carbon and Si@graphite, respectively to improve the electronic conductivity and accommodate the volume expansion of cathode/anode materials. The Si@graphite anode was further prelithiated by Li metal powder to meet the assembly requirement of lithium-ion sulfur battery. The obtained battery realizes a significant enhancement in safety attributed to the lower flammability of OSE and the elimination of Li metal. This solid-like electrolyte was creatively fabricated by integrating the traditional ether-based liquid electrolyte with two functional components, SiO2 hollow nanosphere layer, and FEC additive. The aggravated shuttle effect in lithiated Si�S batteries is properly suppressed by the SiO2 hollow nanosphere layer, meanwhile the FEC additive benefits the formation of a robust and thin SEI with low interface resistance on the Si composite anode. More importantly, owing to the elimination of Li metal and the application of OSE, the obtained lithiated Si�S batteries exhibit a significantly better safety in forms of low flammability and strong recovery ability against short-circuit over traditional Li�S batteries