Development of Garnet-Type Li Ion Electrolytes for All-Solid-State Li Ion Batteries

Abstract

The high energy density Li ion batteries require a replacement of currently used organic polymer electrolyte with highly conducting solid-state materials in terms of safety reasons. Solid electrolytes exhibiting high total Li ion conductivity, negligible electronic conductivity and wide electrochemical window (up to 6 V/Li/Li+) are preferable for application in solid-state Li ion batteries [1,2]. Garnet-like oxides, with general formula, Li5La3M2O12 (M = Nb, Ta) are emerged as a promising class of Li+ conductors among several other solid-state materials [1]. The increase in Li content has proven to be increasing the Li ion conductivity of garnets and Li7La3Zr2O12 have a highest conductivity of the order of 10-4 Scm-1 at ambient condition [3]. In this talk, we report the effect of excess Li added during synthesis to avoid Li volatilization on the ionic conductivity of garnet-type materials and discuss the recent developments on optimization of ionic conductivity of garnets.