Improvement of Interfacial Properties of Sulfide Based All-Solid-State Lithium Secondary Batteries with Li-Si Alloy Anode

Li₂₂Si₅ alloy powder was synthesized by mechanical alloying and its electrochemical performance was investigated for use in solid-state battery anodes. Using these anode materials, all-solid-state lithium batteries were assembled with Li₄Ti₅O₁₂ (LTO) or titanium disulfide (TiS2) as cathode and Li₂S-P₂S₅ as electrolyte. Galvanostatic charge/discharge tests were also performed, and capacity was increased about two times by the additional powder milling process with gradient sturucure, which is consistent with the impedance results. Thus, the results from the present work indicate that using the secondary milling process to refine the electrode powder and gradient structure to reduce interfacial resistance are effective ways to increase the kinetics of alloying and de-alloying with higher utilization of anode active material in all-solid-state lithium secondary batteries.