High conductive composite polymer electrolyte via in situ UV-curing for all-solid-state lithium ion batteries

All-solid-state lithium ion batteries are considered to be one of the best candidates for next generation batteries due to the high safety and energy density, but there is still a severe challenge for seeking the high-performance solid electrolytes with high ionic conductivity. Most importantly, the huge resistance at the electrode/electrolyte interface limits their applications. In this work, we investigate an in situ building method of a solid electrolyte, which constructs a composite electrolyte on the cathode by UV-curing and reduces the interfacial impedance by 69.1%. The solid electrolyte shows a decent ionic conductivity of 2.21 × 10–5 S cm–1 at 25 °C and presents a wide electrochemical stability window (>4.7 V vs Li+/Li). The all-solid-state LiFePO4/Li cell displays a high discharge capacity of 147 mAh g–1 and good capacity retention of ∼82% in 100 cycles under 0.1 C at room temperature. The strategy for in situ fabrication of a composite polymer electrolyte shows a promising way for the applicati...