20:T495,Zinc-based electrochemistry is attracting significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. However, the grid-scale application is plagued by limited output voltage and inadequate energy density when compared with more conventional Li-ion batteries. Herein, we propose a latent high-voltage MnO₂ electrolysis process in a conventional Zn-ion battery, and report a new electrolytic Zn-MnO₂ system, via enabled proton and electron dynamics, that maximizes the electrolysis process. Compared with other Zn-based electrochemical devices, this new electrolytic Zn-MnO₂ battery has a record-high output voltage of 1.95 V and an imposing gravimetric capacity of about 570 mAh g^-1 , together with a record energy density of approximately 409 Wh kg^-1 when both anode and cathode active materials are taken into consideration. The cost was conservatively estimated at -1 with an energy efficiency of 93% at 20 mA g^-1 and a long life of 1000 cycles with a capacity retention of 87% at 500 mA g^-1. The pouch zinc batteries with a respective depth of discharge of 89% (C4Q) and 49% (zinc anode) can deliver an energy density of 220 Wh kg^-1 by mass of both a C4Q cathode and a theoretical Zn anode. We also develop an electrostatic potential computing method to demonstrate that carbonyl groups are active centers of electrochemistry. Moreover, the structural evolution and dissolution behavior of active materials during discharge and charge processes are investigated by operando spectral techniques such as IR, Raman, and ultraviolet-visible spectroscopies. Our results show that batteries using quinone cathodes and metal anodes in aqueous electrolyte are reliable approaches for mass energy storage.

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