(Invited) Garnet-Based Hybrid Composite Electrolytes for the All-Solid-State Li-S Battery

Abstract

Lithium sulfur (Li-S) batteries have emerged as one of the most promising post LIBs technologies with a remarkably high theoretical energy density and abundance of elemental sulfur. Nonetheless, there are many problems associated with lithium sulfur batteries such as safety hazard due to lithium dendrite formation and fast capacity decay due to polysulfide dissolution effect.1 Solid electrolytes are promising to prevent lithium dendrite formation and polysulfide dissolution. Among different ceramic electrolytes garnet-type solid inorganic electrolytes are very promising because of its high ionic conductivity and stability with metallic lithium. But the high interfacial resistance with the electrode is the major bottleneck for the practical use of garnet electrolyte.2 However, polymer-based solid electrolytes possess low interfacial resistance but associated low ionic conductivity at room temperature is the biggest challenge for the utilization in solid-state-batteries.3 Recent research theme of Thangadurai group is mainly focused on garnet-type and polymer-garnet composite electrolytes for the practical utilization in all-solid-state Li batteries. Surface modifications of the garnet-type electrolytes and novel composite electrolytes developed in the laboratory have been successfully employed in all-solid-state-Li-S batteries even at room temperature. Fabrication of these electrolytes in bulk scale, characterizations, electrochemical properties and all-solid-state-Li-S battery performances will be discussed.