Garnet structured solid fast Li+ conductor as polysulfide shuttle inhibitor in Li-S battery

Abstract

Herein, we demonstrate strategies to control polysulfide shuttling phenomenon in Li-S batteries using lithium garnet solid electrolyte Li6.4La3Zr1.4Ta0.6O12 (LLZTO). Thin-walled LLZTO membrane and polypropylene (PP) separator decorated with LLZTO (PP-D (LLZTO)) and infiltrated with small amount of liquid electrolyte (LE) have been used to control the polysulfide diffusion in Li-S batteries. The fabricated Li||PP-LE-LLZTO-LE||S coin cell delivered an initial discharge capacity of 1100 mA h g−1 at a current density of 0.03 mA cm−2 (~16.55 mA gsulfur−1) and discharge capacity of 706 mA h g−1 with nearly 100% coulombic efficiency at the 30th charging/discharging cycle. The Li||LE-PP-D(LLZTO)||S coin cell delivered an initial discharge capacity of 855 mA h g−1 at a current density of 0.39 mA cm−2 (~167.3 mA gsulfur−1) and a discharge capacity retention of nearly 560 mA h g−1 after 40th charging/discharging cycle.