Zefang Yang, Qi Zhang, Chao Hu, Yougen Tang, Jie Li, Qi Wang, Wanhai Zhou, Dongliang Chao, Haiyan Wang
Abstract Electrolytic Zn–MnO 2 batteries are promising candidates for safe and sustainable energy storage owing to their high voltage, environmental benignity, and cost-effectiveness. However, practical applications are hindered by the poor conductivity and the irreversible dissolution of conventional ε-MnO 2 deposits. Herein, we report a scalable semisolid slurry electrode architecture that enables stable MnO 2 deposition/dissolution using a three-dimensional percolating network of carbon nanotubes (CNTs) as both conductive matrix and deposition host. The slurry system promotes the formation of highly conductive γ-MnO 2 owing to enhanced charge transfer kinetics, enabling overall dissolution rather than the localized separation typically seen in traditional electrodes. The Zn–MnO 2 slurry cell exhibits a reversible areal capacity approaching 60 mAh cm −2 . Moreover, the flowable nature of the slurry allows electrochemically inactive MnO 2 formed during dissolution to be reconnected and reactivated by CNTs in the rheological network, ensuring deep utilization and cycling stability. This work establishes a slurry electrode strategy to improve electrolytic MnO 2 reactions and offers a viable pathway toward renewable aqueous batteries for grid-scale applications.