Influence of Ga-Ge Doping on the Structural and Electrical Properties of Li7La3Zr2O12 Solid Electrolytes For Li ion Battery

TL;DR

This study investigates how Ga-Ge doping affects the structure and electrical conductivity of Li7La3Zr2O12 solid electrolytes, identifying an optimal doping level that enhances ionic conductivity for lithium-ion batteries.

Contribution

It introduces a systematic doping approach with Ga in Li7La3Zr2O12, demonstrating improved ionic conductivity suitable for solid-state battery applications.

Findings

0.20 Ga sample has highest ionic conductivity of 5.09 x 10^-4 S/cm

Optimal doping level reduces activation energy to 0.25 eV

Structural analysis confirms phase stability with doping

Abstract

In order to replace the conventional liquid electrolytes by solid electrolytes, high room temperature ionic conductivity is required. To achieve such high ionic conductivity, the series Li7-3xGaxLa3Zr1.9Ge0.1O12 was prepared by solid-state reaction method. The content of Ge was kept constant at 0.10 a.p.f.u, and the Ga has been varied from 0 to 0.40 a.p.f.u. The conducting cubic phase was identified using X-ray diffraction study, whereas the physical and structural studies were perfomed using density measurements and scanning electron microscopy (SEM) analysis, respectively. Electrical conductivity results reveal that the 0.20 Ga ceramic sample possessed the highest room temperature Li ion conductivity of 5.09 x 10-4 S/cm and minimum activation energy of 0.25 eV. Predominant ionic conduction in 0.20 Ga ceramic sample was confirmed by the DC polarization method. The high room temperature ionic conductivity makes the 0.20 Ga ceramic sample a suitable candidate as a solid electrolyte for all-solid-state lithium-ion batteries (ASSLIBs).