Specific Features of the Formation of Cubic Al-Substituted Li₇La₃Zr₂O₁₂

Abstract— Samples of a lithium-conducting solid electrolyte of garnet structure, namely, tetragonal Li₇La₃Zr₂O₁₂ and cubic Li_6.4Al_0.2La₃Zr₂O₁₂, were prepared. The specific features of the formation of the highly conducting cubic modification of the solid electrolyte Li_6.4Al_0.2La₃Zr₂O₁₂ were determined. The ionic and electronic conductivity were determined by the electrochemical impedance spectroscopy and potentiostatic chronoamperometry. Cubic Li_6.4Al_0.2La₃Zr₂O₁₂ with the ionic conductivity of ~2 × 10^–4 S cm^–1 and electronic conductivity lower than 3 × 10⁻⁹ S cm^–1 at 20°С is a promising material for a solid-state lithium–ion batteries.