Impact of Ce Substitution on Structural and Electrochemical Properties of Ga Doped Garnet Li7La3Zr2O12 Solid Electrolyte

TL;DR

This study investigates how Ga-Ce co-doping affects the structure and ionic conductivity of garnet Li7La3Zr2O12 solid electrolytes, aiming to enhance their performance for solid-state Li-ion batteries.

Contribution

It introduces a new co-doping approach with Ga and Ce to improve ionic conductivity in garnet electrolytes, identifying optimal doping levels for better battery performance.

Findings

Ce doping at 0.10 a.p.f.u. yields highest ionic conductivity (4 x 10^-4 S/cm)

Ce doping reduces activation energy to 0.29 eV

Samples show predominant ionic conduction suitable for solid-state batteries

Abstract

In order to replace conventional liquid electrolytes, solid electrolyte should possess high ionic conductivity. In this study, the effects of Ga-Ce co-doping on the garnet Li7La3Zr2O12 solid electrolyte have been investigated. The series Li6.4Ga0.2La3Zr2-xCexO12 has been prepared with varying content of Ce from 0 to 0.30 atoms per formula unit (a.p.f.u.) by sintering at 1050^0C. Various structural characterizations namely X-diffraction, Scanning Electron Microscopy (SEM), density measurements were carried out. The electrochemical analysis suggested that, the sample with 0.10 a.p.f.u. of Ce offered the highest room temperature ionic conductivity of 4 x 10-4 S/cm with the minimum activation energy of 0.29 eV. Moreover, DC conductivity measurement proved the predominant ionic conduction in the prepared samples making it suitable for the application in all solid state Li-ion batteries (ASSLIBs).