Since the commercialization of LIBs, only organic liquid electrolytes have been used in commercial systems. However, their use poses a significant safety concern for emerging applications such as electric vehicles and grid storage because of the high risk of leakage and flammability. In addition, dendritic lithium growth over extended cell cycling can lead to short circuits in LIBs when a lithium metal anode and organic liquid electrolyte are used. Some cathode materials also have a tendency to dissolve in the electrolyte (e.g., Mn ions in LiMn2O4 spinel cathodes), which can further reduce the overall efficiency of LIBs. To circumvent these issues, the replacement of organic liquid electrolytes with inorganic solid-state electrolytes (SSEs) has been suggested. Meanwhile, the continuously increasing requirement of battery's rate capacity asks further understanding and improving ionic kinetics in state-of-the-art electrode materials.