Lithium-Cation Conductivity of Solid Solutions in Li_6-xZr_2-xA_xO₇ (A = Nb, Ta) Systems

Abstract

Li6-xZr2-xAxO7 (A = Nb; Ta) system with 0 6Zr2O7 are determined; temperature (200–600 °C) and concentration dependences of conductivity are investigated. It is shown that monoclinic Li6Zr2O7 exhibits better transport properties compared to its triclinic modification. Li5.8Zr1.8Nb(Ta)0.2O7 solid solutions have a higher lithium-cation conductivity at 300 °C compared to solid electrolytes based on other lithium zirconates due the “open” structure of monoclinic Li6Zr2O7 and a high solubility of the doping cations.

Keywords

• solid electrolytes
• lithium zirconates
• lithium cation conductivity
• crystal structure
• glycine-nitrate synthesis
• heterovalent doping