Chemically Self-Charging Aqueous Zinc-Organic Battery

Zn–organic batteries are attracting extensive attention, but their energy density is limited by the low capacity (<400 mAh g–1) and potential (<1 V vs Zn/Zn2+) of organic cathodes. Herein, we propose a long-life and high-rate Zn–organic battery that includes a poly(1,5-naphthalenediamine) cathode and a Zn anode in an alkaline electrolyte, where the cathode reaction is based on the coordination reaction between K+ and the C═N group (i.e., C═N/C–N–K conversion). Interestingly, we find that the discharged Zn–organic battery can recover to its initial state quickly with the presence of O2, and the theoretical calculation demonstrates that the K–N bond in the discharged cathode can be easily broken by O2 via redox reaction. Accordingly, we design a chemically self-charging aqueous Zn–organic battery. Benefiting from the excellent self-rechargeability, the organic cathode exhibits an accumulated capacity of 16264 mAh g–1, which enables the Zn–organic battery to show a record high energy density of 625.5 Wh kg–1.