Failure Mechanisms and Practical Optimizations for Ah-Scale Aqueous Zinc-Ion Pouch Cells

Aqueous zinc-ion batteries (ZIBs) are emerging as a key technology for the safe, low-cost, and environmentally friendly large-scale energy storage systems. While the research on coin cells has achieved significant advancements, the failure mechanisms and design strategies of pouch cells that hold great practical potentiality, remain relatively underexplored. This review aims to fill this gap via providing an in-depth exploration of the failure mechanisms and practical optimizations of aqueous zinc-ion pouch cells. A comparative analysis between coin cells and pouch cells is conducted in terms of the research status, bridging principles, and configuration-specific distinctions. Further interpretation of failure mechanisms at both electrodes and device is systematically discussed; these include the instability associated with cathode and anode, and the device-scale failures such as current collector and binder degradation, interfacial mismatch, and packaging-induced defects. The practicality-oriented strategies for Ah-scale pouch cells are further proposed. The final section advocates that future research should emphasize high-loading and large-area design, enhancement of kinetic performance, and tolerance to extreme operating conditions. This review contributes the theoretical insight and practical guidance to Ah-scale aqueous zinc-ion pouch cell technologies, which are expected to promote their application in large-scale energy storage systems.