Effects of surface lithiated TiO2 nanorods on room-temperature properties of polymer solid electrolytes

Polymer solid electrolyte with high ionic conductivity at room-temperature is most likely to be widely used in solid-state lithium batteries. In this work, the novel surface lithiated TiO2 nanorods were firstly used as ionic conductor in polymer solid electrolyte. The surface lithiated TiO2 nanorods-filled polypropylene carbonate polymer composite solid electrolyte (CSE) has an uniform composite structure with a thickness of about 60 mu m. The ionic conductivity at room-temperature is 1.21 x 10(-4) S cm(-1) and the electrochemical stability window is up to 4.6 V (vs Li+/Li). The assembled NCM622/CSE/Li solid-state battery shows a stable cycle performance with a retention capacity of 120 mAh g(-1) after 200 cycles at the current density of 0.3 C and a high coulomb efficiency of 99%. Compared with TiO2 particles, this novel surface lithiated TiO2 nanorods can provide more continuous ion transport channels and more Lewis acid-base reactive sites, provide a novel way to enhance the lithium ion transport in polymer solid electrolyte.