Preparation of Li₄GeO₄–Li₃VO₄ based electrolytes via mechanochemical treatment

Abstract

Pseudo-binary electrolytes of (100 − x)Li₄GeO₄·xLi₃VO₄ (x = 0, 10, 20, 30, 40, and 50 mol %) and pseudo-ternary electrolytes of 45Li₄GeO₄·45Li₃VO₄·10Li_aMO_b (M = B, Si, P, S, Mo, and W) with lithium superionic conductor (LISICON) type structures were prepared by mechanochemical treatment and subsequent heat treatment. For the (100 − x)Li₄GeO₄·xLi₃VO₄ heated samples with LISICON-type structure, the activation energy decreased with increasing Li₃VO₄ content, and the x = 50 sample showed a high conductivity of 1.1 × 10⁻⁴ S cm⁻¹ at 25 °C. The 45Li₄GeO₄·45Li₃VO₄·10Li_aMO_b heated samples with LISICON-type structure showed a conductivity of approximately 10⁻⁵ S cm⁻¹ at 25 °C, and the larger “a” as the Li content in Li_a(Ge_0.45M_0.1V_0.45)O_b contributed to improving the ionic conduction properties of this system.