Emerging strategies for the improvement of modifications in aqueous rechargeable zinc–iodine batteries: Cathode, anode, separator, and electrolyte

Aqueous rechargeable zinc–iodine batteries have gained traction as a promising solution due to their suitable theoretical energy density, cost-effectiveness, eco-friendliness, and safety features. However, challenges such as the polyiodide shuttle effect, low iodine cathode conductivity, zinc anode dendritic growth, and the requirement for efficient separators and electrolytes hinder their commercial prospects. Hence, this review highlights recent progress in refining the core optimization strategies of zinc–iodine batteries, focusing on enhancements to the cathode, anode, separator, and electrolyte. Cathode improvements involve the addition of inorganic, organic, and hybrid materials to counteract the shuttle effect and boost redox kinetics, where these functional materials also are applied in anode modifications to curb dendritic growth and enhance cycling stability. Meanwhile, cell separator design approaches that effectively block polyiodide shuttle while promoting uniform zinc deposition are also discussed, while electrolyte innovations target zinc corrosion and polyiodide dissolution. Ultimately, the review aims to map out a strategy for developing zinc–iodine batteries that are efficient, safe, and economical, aligning with the demands of contemporary energy storage.