Regulating the Conversion Efficiency and Kinetics of Halogen‐Based Reactions for High‐Performance Aqueous Zn Batteries

Aqueous zinc‐halogen batteries (AZHBs) are considered as a potential contender for energy storage fields due to their inherent safety, multi‐electron redox pathways, high capacity, and superior redox potentials. Although significant progress has been achieved in AZHBs, their relatively low conversion efficiency and slow kinetics have hindered their further practical application. Based on this, this review focuses on fundamental aspects of halogen conversion electrochemistry based on different redox routes to deepen systematic attention and understanding for improved AZHBs. Herein, the conversion chemistry and relative issues of AZHBs including two‐electron, four‐electron, and multi‐electron redox routes are thoroughly summarized first. Subsequently, understanding the challenges of thermodynamics and kinetics challenges of different halogen‐based cathodes of AZHBs are discussed and explored in depth. Importantly, we provide improvement strategies for constructing halogen cathodes with two‐electron transfer, multi‐electron transfer, and achieving synergistic effects with other redox couple. Finally, further explorations in intercalation‐conversion dual‐energy storage mechanisms, anode protection, and electrolyte regulations are considered as valuable directions for the future development of high‐performance AZHBs.