Dual-Halide Interphase Enabling High-Performance Lithium Metal Batteries in Wide-Temperature Range

Robust lithium-ion diffusion kinetics enable superior battery performance even under harsher conditions, but the complex processes containing transport via liquid, interphase, and solid phases make it challenging. Herein, a dual halide-based electrode/electrolyte interphase (EEI) strategy is proposed to boost the Li+ ion diffusion kinetics through rational design of electrolyte. This dual-halide EEI not only accelerates interfacial Li+ diffusion but also protects electrodes from taking side reactions under high-voltage and harsh temperatures. Benefiting from these features, the Li/LiCoO2 cells deliver an impressive performance at high-voltage window 4.5 V (209 mAh g–1, 95.2% capacity retention after 100 cycles) and wide temperatures (98.1% capacity retention at 60 °C after 100 cycles; 87.7% capacity retention at −20 °C after 20 cycles). These results well demonstrate the efficiency of this dual halide EEI, which empowers lithium metal batteries toward practical applications.