An Ultrafast Air Self-Charging Zinc Battery.

Air self-charging power systems possess the capability of energy harvesting, conversion, and storage simultaneously. However, in general, their self-charging rate is slow and the batteries cannot be oxidized to the fully charged state due to the weak oxidizability of O . Herein, an ultrafast air self-charging aqueous zinc battery is designed by constructing a polyaniline@Pt/C (PANI@Pt/C) composite cathode. The introduction of Pt/C catalyst endows the redox reaction between PANI and O with fast reaction kinetics and extended redox potential difference. Therefore, the self-charging rate of the Zn/PANI@Pt/C batteries is effectively accelerated and they can be self-charged to fully charged state. Furthermore, the PANI can be recharged by O simultaneously during discharging process to compensate the consumed electrical energy, achieving prolonged energy supply. In addition, the PANI@Pt/C cathodes can be directly used as the cathodes of flexible self-charging zinc batteries due to their excellent mechanical properties. As a proof of concept, flexible soft-packaged Zn/PANI@Pt/C batteries are fabricated and displayed stable electrochemical performance and self-rechargeability even at different bending states. A route is provided here to design ultrafast chemical self-charging energy storage devices and the horizons of flexible energy storage devices are broadened.