XRD and SEM Analyses of Bulk Ga-Doped Li₇La₃Zr₂O₁₂Li- Ion Conducting Solid Electrolyte Prepared via Hot-Pressing Method

Abstract

In this study, bulk lithium-ion conducting solid electrolyte of Ga-doped Li7La3Zr2O12 (Li7-3XGaxLa3Zr2O12) where x = 0.1 (Ga-LLZO) was prepared via hot pressing at 500 °C. Precursor powder for hot-pressing was prepared using conventional solid state reaction method. Planetary ball milling was employed to investigate the particle size effect on the structure and densification of hot-pressed samples. XRD patterns of the bulk hot-pressed sample revealed a crystalline phase of which the major peaks observed can be indexed to a cubic LLZO structure; however, a major impurity phase of La2Zr2O7 was observed for the ball-milled sample. Thermogravimetric and differential thermal analysis showed about 12% weight loss below 900 °C which may have affected the observed hot-pressing structure. Although lower density measurement and an impurity phase of La2Zr2O7 were observed for the ball-milled sample, ball-milling also resulted to a more homogeneous and finer particle size as shown by SEM images results.

Fabrication of LiFePO₄-Based Composite Cathode Deposited on LLTO Li-Ion Conducting Solid Electrolyte via Slurry Coating and Hot-Pressing

“…3g and 3h, the surface morphology became denser as compared to the just asdried and normal heat treatment. Thus, densification by both temperature and mechanical pressure or hot-pressing provides a denser morphology [7,11,12]. It is important to note that the hot-pressing temperature was done only at 450 o C due to the expected decomposition of LiFePO4 at higher temperatures [10].…”

“…This method is prone to producing a porous cathode surface from the evaporation of the organic solvent. However, this method can be improved with hot-pressing [7] which provides better densification [8]. Hence, in this study, LFPO-based cathode was deposited on LLTO solid electrolyte substrate via slurry coating and the effects of heat treatment and pressure via hot-pressing were investigated.…”