Elaborate molecular design on cathodes is of great importance for rechargeable aqueous zinc-organic batteries' performance elevation. Herein, we design a novel orthoquinone-based covalent organic framework with an ordered channel structures (BT-PTO COF) cathode for an ultrahigh performance aqueous zinc-organic battery. The ordered channel structure facilitates ions transfer and makes the COF follow a redox pseudocapacitance mechanism. Thus, it delivers a high reversible capacity of 225 mAh g À 1 at 0.1 A g À 1 and an exceptional long-term cyclability (retention rate 98.0 % at 5 A g À 1 ( � 18 C) after 10 000 cycles). Moreover, a co-insertion mechanism with Zn 2 + first followed by two H + is uncovered for the first time. Significantly, this co-insertion behaviour evolves to more H + insertion routes at high current density and gives the COF ultra-fast kinetics thus it achieves unprecedented specific power of 184 kW kg À 1 (COF) and a high energy density of 92.4 Wh kg À 1 (COF) . Our work reports a superior organic material for zinc batteries and provides a design idea for future high-performance organic cathodes.

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The aqueous zinc-ion battery has the advantages of environmental friendliness, safety, and reliability, which is expected to be used for large-scale energy storage. However, due to the high activity of water, the hydrogen evolution reaction (HER) easily occurs on the surface of the zinc anode during the charge-discharge process, which is accompanied by corrosion, by-products, and dendrite formation. Herein, a new-type eutectic electrolyte consisting of ZnCl 2 , tetramethylurea (TMU), and H 2 O with the optimal molar ratio of 1:3:1 (ZT-1) is developed for the high-stability zinc anodes. The H 2 O in this system is doubly bound through the coordination with Zn 2+ and the hydrogen bonding with TMU, thus leading to the greatly inhibited activity of H 2 O. In addition, the H 2 O and TMU are successively stripped during the desolvation process of ZnCl 2 (TMU)(H 2 O), followed by the deposition of [ZnCl 2 ] at the zinc interface. In this way, the tendency of HER, corrosion, dendrites, and by-products induced by the decomposition of H 2 O molecules at the zinc interface is minimized, enabling a much more stable plating/stripping process of Zn 2+ . Consequently, the Zn//Zn symmetric cell can stably cycle for >2000 h, while the Zn//Cu half cell can stably cycle 800 times with an average Coulombic efficiency of 99.5%.