Breaking through the thick-electrode barrier: Rational design for high-loading Zn-MnO2 batteries

Abstract

Zn-MnO₂ batteries hold great promise for grid-scale and stationary energy storage applications.Their inherently low cost, safety, and environmental benignity make them ideally suited for gigaton-level energy storage. In recent years, research focus has increasingly shifted toward achieving high areal capacity and energy density, aiming to uncover practically relevant insights for their real-world deployment. However, significant challenges emerge when employing MnO₂ electrodes at elevated areal loadings. In this review, we identify the thick-electrode barrier, encompassing issues that stem from intrinsic material properties and reaction mechanisms, as well as limitations imposed by high-loading electrode configurations. We further provide a comprehensive summary of recent advances toward realizing high areal-capacity Zn-MnO₂ batteries. By connecting fundamental understanding with practical design principles, this review aims to offer guidance for overcoming the thick-electrode barrier and accelerating the practical implementation of Zn-MnO₂ batteries for sustainable energy storage.