《Achieving high-performance Li6.5Sb0.5Ge0.5S5I-based all-solid-state lithium batteries》
Sb-based sulfide electrolytes are promising for all-solid-state lithium batteries due to their ultra-high lithium ion conductivity (10-2 S/cm) and even comparable to current liquid electrolytes. However, the poor electrochemical stability between this electrolyte and the high-voltage layered cathode makes it difficult to achieve excellent battery performance. Here, we successfully synthesized Li6.5Sb0.5Ge0.5S5I electrolyte with ionic conductivity up to 10 m S/cm and revealed the electrochemical failure mechanism of the corresponding battery using bare LiNi0.6Mn0.2Co0.2O2 cathode and Li-In anode. In addition, Li3InCl6 electrolyte is introduced as both an ionic additive for the cathode mixture and an isolation layer to avoid side reactions. The designed battery provides a high discharge capacity of 162.7 mAh / g at 0.5 C and maintains a discharge capacity of 74.5 % after 200 cycles at room temperature. In addition, it can be reversibly cycled between-20 °C and 60 °C, with excellent battery performance. This work provides a general design strategy for the use of highly conductive sulfide electrolytes with low stability in all-solid-state batteries.
https://authors.elsevier.com/c/1gbe18M-op~DHP
