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The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc‐organic batteries. Herein, we have synthesized a Z‐folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+. In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z‐folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215 mAh g−1 at 0.1 A g−1, over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196 mAh g−1 at 20 A g−1. [ABSTRACT FROM AUTHOR]

The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc‐organic batteries. Herein, we have synthesized a Z‐folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+. In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z‐folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215 mAh g−1 at 0.1 A g−1, over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196 mAh g−1 at 20 A g−1. [ABSTRACT FROM AUTHOR]

Aqueous Zn-based batteries deliver thousands of cycles at high rates but poor recyclability at low rates. Herein, we reveal that this illogical phenomenon is attributed to the reconstructed electrode/electrolyte interface at high rates, wherein the condensed electrical double layer (EDL) and the tightly absorbed Zn2+ ions on the Zn electrode surface afford compact and corrosion-resistant Zn deposits. [ABSTRACT FROM AUTHOR]