Electrolyte engineering enables rapid and durable Zn–air self-charging batteries

Abstract

Zinc–air self-charging batteries integrate energy harvesting, storage, and conversion by utilizing ambient oxygen to drive spontaneous redox reactions, but their practical application is limited by sluggish self-charging kinetics and unstable aqueous interfaces. Here we introduce a hybrid electrolyte of N,N-dimethylacetamide (DMAC) with 10 vol% H₂O that achieves rapid and durable Zn–air self-rechargeability. DMAC offers low vapor pressure, high oxygen solubility, and resistance to reactive oxygen species, while the controlled water content supplies protons essential for Zn²⁺ intercalation. This synergy drives the formation of a porous, oxygen-permeable interfacial layer that accelerates Zn²⁺ transport and continuous oxygen reduction. Consequently, the batteries self-charge to 0.9 V within 13 min in an oxygen atmosphere, deliver a record cumulative discharge capacity of 37 392 mAh g⁻¹ over 200 cycles, and maintain high-rate capability. This electrolyte design overcomes intrinsic limitations of aqueous systems and establishes a pathway toward safe, high-performance air self-charging batteries.