Scalable Roll‐to‐Roll Dry Processing of 10 mAh cm ⁻² Iodine Cathodes for Establishing Ah‐Level Aqueous Zn–I ₂ Pouch Cell Evaluation Protocol: Bridging Laboratory Research and Industrial Application

Abstract

Abstract The deployment of aqueous Zn‐I 2 batteries is limited by inadequate energy density, restricted cycle life and the lack of reliable Ah‐level pouch cell evaluation protocols, resulting in the widening gap between laboratory research and industrial application. Herein, a scalable roll‐to‐roll dry‐processing strategy is developed to fabricate high‐areal‐capacity I 2 cathodes, which effectively enhances cell‐level energy density by reducing the proportion of inactive battery components. Through synergistic optimization of electrode composition and manufacturing approach, the resulting 1 mm‐thick AC@I 2 cathode achieves a high areal capacity of 10 mAh cm −2 with record‐breaking lifespan over 15 000 cycles. Critically, decoupling PTFE fibrillation from iodine incorporation allows tunable iodine loadings up to 110 mg cm −2 while minimizing sublimation losses and preserving mechanical integrity. Moreover, the engineered hierarchical conductive network ensures efficient charge transport, with ionic diffusion as the primary rate‐limiting step. Most importantly, the developed pilot‐scale process enables continuous production of electrode rolls exceeding 20 m in length, realizing the straightforward fabrication of Ah‐level Zn‐I 2 pouch cells without complex multilayer stacking. These pouch cells (1.08 Ah) demonstrate stable cycling over 1700 cycles at 2 C. This work establishes a reproducible electrode‐manufacturing methodology and evaluation platform, effectively bridging laboratory innovation with practical battery implementation.