Upgrading Traditional Poly(1,3-dioxolane) Electrolytes via Integrated Design of Ultra-Stable Network for Solid-State Lithium Metal Batteries

Abstract Poly(1,3-dioxolane) (PDOL)-based solid electrolytes are expected to be exploited in solid-state lithium metal batteries (SLMBs) due to their high ionic conductivity, good lithium metal compatibility, and facile preparation method of in-situ polymerization in cells. However, inferior structural stability and low Li-ion transference number (tLi+) still impede PDOL from authentic commercialization. Herein we propose a novel ultrathin crosslinked PDOL-based electrolyte (PTADOL), which is prepared via a multifunctional trimethylolpropane tris[3-(2-methyl-1-aziridine) propionate] additive. The in-situ formed PTADOL not only affords an integrated network configuration with stabilized electrode/electrolyte interface, but also achieves improved oxidative stability, excellent thermal stability, and superior flame retardancy. Moreover, PTADOL has rational O-Li+ coordination for fast Li+ transport, which enhances both ionic conductivity and tLi+. Based on the ultra-stable PTADOL, the high voltage LiNi0.8Mn0.1Co0.1O2||Li batteries exhibit excellent electrochemical performance without electrolyte degradation. This work provides a practical approach to designing a highly stable solid polymer electrolyte for high-performance SLMBs.