Synthesis and Characterization of the New Li_1+x Al_1+x Si_1-x O₄ (x=0-0.25) Solid Electrolyte for Lithium-Ion Batteries

A systematic study was performed to investigate the effect of the sintering temperature, sintering duration, and aluminum doping on the crystalline structure and ionic conductivity of the Li1+xAl1+xSi1-xO4 (LASO; x = 0-0.25) solid electrolyte. There was a strong indication that an increase in the sintering temperature and sintering time increased the ionic conductivity of the electrolyte. In particular, the doping concentration and composition ratio (Li1+xAl1+xSi1-xO4; x = 0-0.25) were found to be crucial factors for achieving high ionic conductivity. The sintering time of 18 h and lithium concentration influenced the lattice parameters of the LASO electrolyte, resulting in a significant improvement in ionic conductivity from 2.11 x 10(-6) (for pristine LASO) to 1.07 x 10(-5) S cm(-1). An increase in the lithium concentration affected the stoichiometry, and it facilitated a smoother Li-ion transfer process since lithium served as an ion-conducting bridge between LASO grains.