Structural and electrical properties of mol% (100 − x)Li<inf>2</inf>SO<inf>4</inf>:xP<inf>2</inf>O<inf>5</inf> solid electrolyte system (0 ≤ x ≤ 20)

Extensive research has been focused on solid electrolytes exhibiting high lithium ion conductivity, with the goal of advancing their use in solid-state lithium-ion batteries. This study investigates the influence of a glass former, P2O5, on the structure and ionic conductivity of the solid electrolyte Li2SO4. Quenching of Li2SO4 in the presence of P2O5 resulted in a glass–crystal composite with significant amorphous content. The XRD analysis of the 20 mol% glass ceramics detects the presence of Li4P2O7 without altering the original crystal structure. Notably, a conductivity value of 1.11 × 10−4 S cm−1 at 563 K was observed for 20 mol%, which is around two orders higher than that of polycrystalline Li2SO4. The introduction of a small amount of glass former P2O5 appears to loosen the structure of Li2SO4 creating an easier path for Li+ ion migration in the combined SO4–PO4 network structure.