Constructing high-capacity and flexible aqueous zinc-ion batteries with air-recharging capability using organic cathodes

Abstract

Flexible aqueous zinc-ion batteries (AZIBs) with air-recharging capability are a promising self-powered system applied in future wearable electronics. It is desired to develop high-capacity air-rechargeable AZIBs. Herein, we developed a flexible AZIB with air-recharging capability based on trinitrohexaazatrinaphthylene (TNHATN) cathode and a ZnSO4 electrolyte. The flexible Zn//TNHATN battery exhibits high volumetric energy density (21.36 mWh/cm3) and excellent mechanical flexibility. Impressing, the discharged flexible Zn//TNHATN battery can be chemical self-charged via the redox reaction between TNHATN cathode and O2 from the air. After oxidation in air for 15 h, such flexible Zn//TNHATN battery can deliver a high specific capacity of 320 mAh/g at 0.5 A/g, displaying excellent air-recharging capability. Notably, this flexible Zn//TNHATN battery also works well in chemical or/and galvanostatic charging mixed modes, showing reusability. This work provides a new insight for designing flexible aqueous self-powered systems.