'Environment-friendly' polymer solid electrolyte membrane via a rapid surface-initiating polymeration strategy

High ionic conductivity, strong stability to lithium metal, convenient preparation and good adaptability to cathodes are the important prerequisites for the practical application of solid-state electrolytes (SE). In this work, an 'environment-friendly' poly(1,3-dioxolane) (PDOL) solid electrolyte membrane was for the first-time prepared by a rapid surface-initiating 1,3-dioxolane (DOL) polymeration process under the interaction of substrate and initiator. The -SiO3, -CaO5 and -NaO3 groups on the surface of glass substrate can react with the oxygen atoms on the DOL ring, initiate the rings opening and polymerizing to be long chains under the action of LiPF6, which provides an efficient and environment-friendly preparation method for PDOL membrane without any organic solvent release, and the monomer conversion rate of the DOL reaches 97.6%. This highly polymerized PDOL electrolyte is friendly to the lithium metal environment and shows strong stability, the Li/SE/Li cell can run stably for nearly 4000 h at a current density of 0.3 mA/cm2. High electrochemical stability window up to 5.0 V enables PDOL electrolyte friendly adapt to various cathode environments including sulfur (S) and LiFePO4, and LiCoO2 and Li(Ni0.6Co0.2Mn0.2)O2 (NCM622). The assembled NCM622/SE/Li solid-state soft-pack battery can be cycled for 300 cycles at 0.5 C with the capacity retention of 85%. This PDOL electrolyte membrane shows a high promising commercial application prospect due to its friendly and high-efficiency polymerization process and strong adaptability to electrodes.