Pre‐Sodiation Strategies for Sodium‐Ion Batteries: From Mechanisms to a Multidimensional Evaluation Framework

ABSTRACT

The irreversible consumption of sodium ions during the initial cycle, leading to low initial Coulombic efficiency and rapid capacity decay, poses a fundamental bottleneck to the commercialization of sodium‐ion batteries. While pre‐sodiation has emerged as a pivotal strategy to compensate for this sodium deficit, the field currently lacks a systematic methodology to critically assess and rationally select among diverse pre‐sodiation tactics beyond mere electrochemical metrics. This review addresses this need by synthesizing existing evaluation criteria into a structured multidimensional assessment paradigm. We first delineate the mechanistic underpinnings of physical, electrochemical, chemical, and additive‐based pre‐sodiation strategies. We then introduce a systematic framework that integrates electrochemical performance, interfacial physicochemical properties, and electrode structural evolution to provide a holistic assessment of pre‐sodiation efficacy. Furthermore, we highlight how advanced operando and ex situ characterization techniques decode underlying compensation mechanisms and quantify kinetic improvements. Finally, a comparative analysis based on controllability, scalability, and manufacturing compatibility is presented, offering strategic guidelines for protocol selection. Ultimately, this work provides a foundational reference and a practical decision‐making guide, facilitating the rational design of efficient pre‐sodiation technologies for practical sodium‐ion batteries.