Mechanically Robust Ultrathin Solid Electrolyte Membranes Using a Porous Net Template for All-Solid-State Batteries

Abstract

All-solid-state batteries (ASBs) have been identifiedas a potentialnext-generation technology for safe energy storage. However, the currentpellet form of solid electrolytes (SEs) exhibits low cell-level energydensities and mechanical brittleness, and this has hampered the commercializationof ASBs. In this work, we report on the development of an ultrathinSE membrane that can be reduced to a thickness of 31 mu m withminimal thermal shrinkage at 140 degrees C, while exhibiting robustmechanical properties (tensile strength of 19.6 MPa). Due to its exceptionalionic conductivity of 0.55 mS/cm and the corresponding areal conductanceof 84 mS/cm(2), the SE membrane-incorporated ASB displayscell-level gravimetric and volumetric energy densities of 127.9 Wh/kg(cell) and 140.7 Wh/L-cell, respectively. These valuesrepresent a 7.6- and 5.7-fold increase over those achieved with conventionalSE pellet cells. Our results demonstrate the potential of the developedSE membrane to overcome the critical challenges in the commercializationof ASBs.