Influence of TiO2 nano-particles on the transport properties of composite polymer electrolyte for lithium-ion batteries

The influence of synthesized nano-sized TiO2 particles on the ionic transport properties of PEO (polyethylene oxide)-based composite polymer electrolytes (CPEs) was investigated in this study. The nano-sized TiO2 particles with pure anatase phase can be synthesized by a developed process. It was found that the ionic conductivity of the TiO2 modified CPE increases with a decrease in the grain size of TiO2. The conductivity (σ = 1.40 × 10−4 S cm−1) for the PEO–10% LiClO4–5% TiO2 (3.7 nm) electrolyte is an order of magnitude higher than that the pure PEO–10% LiClO4 (σ = 1.03 × 10−5 S cm−1) at 30 °C. Meanwhile, the transference numbers of 0.51 and 0.21 were obtained for the TiO2 modified CPE and pure PEO–LiClO4, respectively. Both results imply that the nano-sized TiO2 particles in the PEO–LiClO4 matrix provide a new pathway for the transport of lithium ions.