Water as dispersion medium to fabricate homogeneous nano-hectorite solid-state electrolyte for suppressing lithium dendrite

The rational design of green chemical, low-cost, and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and ultralong cycle life Li-metal batteries. Herein, a homogeneous composite solid polymer electrolyte (CSPE) is fabricated with water as the ideal dispersion medium, hectorite (Ht) as nanofiller, and poly (ethylene oxide) (PEO) as the matrix, to guide uniform Li plating/stripping. Benefiting from the merit of Ht can form uniformly dispersed nanosheets in water, the obtained CSPE inheres to a low melting point, robust mechanical property, and high Li⁺ transference number. Moreover, the fabricated Li symmetric battery using PEO-Ht-LiClO₄ CSPE keeps cycling steadily for 4000 h. The well demonstrated water-based CSPE paves the way for developing low-cost, environmentally friendly, and safe solid-state electrolytes for Li-metal batteries.