Tailored high cycling performance in a solid polymer electrolyte with perovskite-type Li_0.33La_0.557TiO₃ nanofibers for all-solid-state lithium ion batteries

Abstract

Solid polymer electrolytes (SPEs) have drawn considerable attention owing to their reliable safety performance, electrochemical stability and exceptional flexibility, which make them superior to conventional liquid electrolytes. Here, we report a novel composite electrolyte which is composed of homogeneously dispersed Li ion-conducting Li_0.33La_0.557TiO₃ (LLTO) nanowires in a poly(ethylene oxide) (PEO)/LiClO₄ matrix. It is demonstrated that only 3 wt% LLTO nanofibers are needed for the optimal performance of SPEs. The PEO-based composite electrolyte shows an excellent Li ion conductivity of 4.01 × 10^-4 S cm^-1 at 60 °C. In addition, it is worth mentioning that the all-solid-state lithium battery based on this composite electrolyte exhibits a specific capacity of 140 mA h g^-1 and an excellent capacity retention of 92.4% after running 100 cycles at a rate of 1C and 60 °C. The study offers a superior alternative for the design of PEO-based solid composite electrolytes.