Solution-processed 2D hectorite nanolayers for high-efficient composite solid-state electrolyte

Abstract

Multiphase composite solid-state electrolytes (CSEs), with excellent customizability and combing the advantages of the inorganic solid electrolyte and solid polymer electrolyte (SPE), have been considered as a promising candidate electrolyte for commercial all-solid-state lithium metal batteries (ASLMBs). Since the performance of CSEs is largely governed by the morphology and structure of the filler, a highly efficient filler material is the key point for achieving high-performance CSEs. Herein, utilizing the super-dispersibility of hectorite (Ht) in water, 2D Ht nanolayers were prepared and combined with poly(ethylene glycol) (PEO) to work as high-performance CSEs. Benefiting from the high specific surface area and surface electronegativity, obtained nanoscale 2D Ht has shown effectively enhanced ionic conductivity and contributed to the mechanical robustness of the composite electrolyte. When 10 wt% of 2D Ht is applied, the ionic conductivity of the composite solid electrolyte reaches up to 1.08 × 10−4 S∙cm−1 at 30 °C, and the tensile modulus and elongation at break rise up to 1.88 MPa and 1270%, respectively. The facile solution-processed filler, consuming lower energy than high-temperature calcination, can provide an efficient strategy for developing advanced ASLMBs.