Reviving Propylene Carbonate for Lithium–Air Batteries

Propylene carbonate (PC), a staple solvent in conventional lithium-ion batteries, has long been deemed incompatible with lithium–air batteries (LABs) despite its favorable physical properties. Herein, we successfully “revive” PC by integrating stannous chloride (SnCl 2 ) into a PC/DMSO dual-electrolyte system. Mechanistically, the solvation structure is engineered such that Sn 2+ cations are preferentially solvated by DMSO and effectively incorporate and stabilize the superoxide intermediate (O 2 – ), shielding PC molecules from nucleophilic attack of superoxide intermediates. While PC molecules exist predominantly as free solvents, slightly modulating the solvation sheath facilitates Li + transport and mitigates the anode degradation. Consequently, this synergistic design enables the PC-based battery to achieve 255 cycles at 500 mA g –1 with a cutoff capacity of 1000 mAh g –1 . This breaks the curse of LAB’s failure with carbonate-based solvents and may shed light on the design of advanced electrolyte systems for LABs.