Solid-state electrolyte, cathode electrode, and methods of making same for sulfide-based all-solid-state-batteries

Abstract

Current sulfide solid-state electrolyte (SE) membranes utilized in all-solid-state lithium batteries (ASLBs) have a high thickness (0.5˜1.0 mm) and low ion conductance (<25 mS), which limit the cell-level energy and power densities. Based on ethyl cellulose's unique amphipathic molecular structure, superior thermal stability, and excellent binding capability, this work fabricated a freestanding SE membrane with an ultralow thickness of 47 μm. With ethyl cellulose as an effective disperser and binder, the Li6PS5Cl is uniformly dispersed in toluene and possesses superior film formability. In addition, ultralow areal resistance of 5.10 Ωcm−2 and remarkable ion conductance of 190.11 mS (one order higher than the conventional sulfide SE layer) have been achieved. The ASLB assembled with this SE membrane delivers cell-level high gravimetric and volumetric energy densities of 175 Wh kg−1 and 675 Wh L−1, individually.

Dependencies are inferred from the claim text.