Li 2-3x Al x S (0 ≤ 0.1667) was prepared via the planetary ball-milling method. Diffuse reflection UV-Vis measurements revealed that band gap and electronic structure of 2 changed with formation defective S. Compared = 0, ionic conductivity for sample 0.1334 improved by ∼3 orders magnitude. The lithium movement activation energy pre-exponential factor A were found to be dependent on value. S, a...