Sol–gel preparation of Li+ ion conductive thin film

Abstract Thin film of a lithium ionic conductor, LiTi 2 (PO 4 ) 3 (LTP), was prepared by sol–gel method from an alkoxide solution. Heating temperature of the spin-coated film between 600 and 800 °C resulted in single-phase LTP films. The film heated at 800 °C showed a reticulation texture with a thickness of 300 nm. It showed a high lithium ionic conductivity 4.4×10 −6 S/cm, although it has a large porosity due to the texture. High sintering capability of the sol–gel film was regarded to reduce a grain boundary resistance in LTP substance, resulting in the high conductivity.