Assembling All-Solid-State Lithium-Sulfur Batteries with Li₃ N-Protected Anodes

The construction of all-solid-state batteries is now easier after the successful synthesis of sulfur-based solid electrolytes with extremely high ionic conductivities. Utilizing lithium metal as the anode in these batteries requires a protective solid electrolyte layer to prevent corrosion due to the highly reactive nature of lithium. Li₃ N coating on lithium metal is a promising way of preventing the degradation of the electrolyte during charge and discharge. In this study, utilization of a Li₃ N-coated lithium anode and Li₇ P₃ S₁₁ solid electrolyte are reported, where a quaternary reduced graphene oxide (rGO)/S/carbon black/Li₇ P₃ S₁₁ composite is used as cathode in the assembled cell. Our results indicate that protecting the Li metal with a Li₃ N coating does not affect the electrochemical characteristics of the cell and extends the cycle life of the battery. A cell assembled with a protective layer was shown to having 306 mAh g^-1 capacity after 120 cycles at 160 mAh g^-1 current density, whereas a cell without protective layer had a capacity of 260 mAh g^-1 .