A Li-Rich Fluorinated Lithium Zirconium Chloride Solid Electrolyte for 4.8 V-Class All-Solid-State Batteries.

Chloride solid-state electrolytes (SEs) represent an important advance for applications in all-solid-state batteries (ASSBs). Among various chloride SEs, lithium zirconium chloride (LiZrCl) is an attractive candidate considering the high natural abundance of Zr. However, LiZrCl meets the challenge in practical ASSBs because of its limited ionic conductivity and instability when paired with high-voltage cathodes.

An Active Halide Catholyte Boosts the Extra Capacity for All-Solid-State Batteries.

Replacing flammable organic liquid electrolytes with nonflammable solid electrolytes (SEs) in lithium batteries is crucial for enhancing safety across various applications, including portable electronics, electric vehicles, and scalable energy storage. Since typical cathode materials do not possess superionic conductivity, Li-ion conduction in the cathode predominantly relies on incorporating a significant number of SEs as additives to form a composite cathode, which substantially compromises the energy density of solid-state lithium batteries. Here, a halide SE, LiVCl is demonstrated, which not only exhibits a decent Li conductivity, but more importantly, delivers a highly reversible capacity of approximately 80 mAh g with an average voltage of 3 V versus Li/Li.

Promoting high-voltage stability through local lattice distortion of halide solid electrolytes.

Stable solid electrolytes are essential to high-safety and high-energy-density lithium batteries, especially for applications with high-voltage cathodes. In such conditions, solid electrolytes may experience severe oxidation, decomposition, and deactivation during charging at high voltages, leading to inadequate cycling performance and even cell failure. Here, we address the high-voltage limitation of halide solid electrolytes by introducing local lattice distortion to confine the distribution of Cl, which effectively curbs kinetics of their oxidation.

NaCrZrCl: A New Halide-Based Fast Sodium-Ion Conductor.

All-solid-state batteries employing solid electrolytes (SEs) have received widespread attention due to their high safety. Recently, lithium halides are intensively investigated as promising SEs while their sodium counterparts are less studied. Herein, a new sodium-ion conductor with a chemical formula of NaCrZrC is reported, which exhibits high room temperature ionic conductivity of 0.