Ionic conductivity of lithium chloroboracite/polyethylene glycol composites

Novel ion-conductive inorganic/organic composites were prepared from lithium chloroboracite (Li4B7O12Cl) and polyethylene glycol (PEG). Li4B7O12Cl was stable under ambient conditions and was easily prepared by a sol–gel reaction. The maximum ionic conductivity of the composites was observed when the composite was prepared in the ratio of Li4B7O12Cl/PEG=60/40 (weight/weight), and it was 1.6×10−6 S/cm at 30 °C and 2.0×10−5 S/cm at 80 °C, respectively. Addition of LiN(SO2CF3)2 to the polymer matrix of the composites increased the ionic conductivity. The Li4B7O12Cl/PEG composites were mechanically tougher than Li4B7O12Cl itself.