A High-Performance Self-Reinforced PEO-Based Blend Solid Electrolyte Membrane for Solid-State Lithium Ion Batteries

The application of lithium-ion batteries is increasing, but the safety problems of traditional liquid lithium-ion batteries have not been fully resolved. Design and manufacture of solid electrolytes can thoroughly solve the problems. A self-reinforced poly(ethylene oxide) based blend solid electrolyte (PEO-BSPE) membrane was designed and prepared successfully by in-situ polymerization of ethoxylated trimethylolpropane triacrylate (ETPTA) in PEO electrolyte matrix under UV light to form a high-strength three-dimensional network structure. XRD and FESEM analyses proved that PEO-BSPE membranes were amorphous, smooth and flexible. The tensile strength of PEO-BSPE was 20 times higher than that of PEO-SPE film. PEO-BSPE also had good safety and low glass transition temperature. The ionic conductivity of PEO-BSPE at 55 degrees C increased to 1.3 x 10(-4) S cm(-1). The electrochemical stability window of PEO-BSPE was 5.6 V. The solid-state battery was assembled with PEO-BSPE. The solid-state battery (LiFePO4/PEO-BSPE/Li) had good cycle stability, low interface impedance (189 omega cm(-2)), high coulombic efficiency (>98%), high average specific discharge capacity (>135 mA h g(-1) at 0.1 C) and excellent C-rate performance at 55 degrees C. Hence the PEO-BSPE membrane is a very hopeful candidate for applying in all-solid-state lithium battery.