A preliminary investigation of fracture toughness of Li7La3Zr2O12 and its comparison to other solid Li-ion conductors

This is the first report of fracture toughness analysis of a new ceramic electrolyte (Li7La3Zr2O12). The fracture toughness was measured using an indentation technique and subsurface crack propagation was analyzed using a novel focused ion beam/scanning electron microscope (FIB-SEM) technique. The fracture toughness of polycrystalline Li7La3Zr2O12 was between 0.86-1.63 MPa root m. FIB-SEM analysis of the indentation cracks suggested that both half-penny and Palmquist cracks were present. The fracture toughness of Li7La3Zr2O12 is comparable to other state of the art ceramic electrolytes such as Li0.33La0.57TiO3 and Li1.3Al0.3Ti1.7(PO4)(3). (C) 2013 Elsevier B.V. All rights reserved.