(625g) Long Lasting Li-S Batteries Via Suppressing Lithium Dendrites

Due to high theoretical capacity, low negative potential and prospective for next-generation Li-S batteries, Lithium (Li) metal has received huge attention as a promising anode, where stable Li metal electrode is crucial. However, Li dendritic growth and unstable solid electrolyte interphase (SEI) layer result in poor electrochemical performances and safety problems (e.g. short-circuit). Distinctive design of nanoporous SiO₂ nanosheet layer is coated on separator in order to uniformly control Li-ion flux and minimize the lithium dendrite formation. The propagation of Li dendrites against the separator was dramatically restrained and suppressed via porous SiO₂ nanosheets, thus leading to significant enhancement of electrochemical performances of Li metal and in Li-S batteries. Li-S prototype cell coupled with designed SiO₂ nanosheet membrane delivered stable cycle retention (over 400 cycles) with high Coulombic efficiency by selectively allowing Li ions to pass through functional separator and preventing the migration of polysulfides.