Fiber-Based Flexible Zinc-Ion Batteries: Recent Advances and Future Perspectives

Abstract

Fiber-based flexible zinc-ion batteries (FFZIBs) represent a new class of next-generation energy storage systems distinguished by their low mass, outstanding mechanical deformability, superior textile compatibility, and inherent operational safety. These unique attributes make them particularly suitable for wearable electronics and smart textile applications. Nevertheless, the practical deployment of FFZIBs is still hindered by multiple intrinsic challenges, such as inadequate energy density, uncontrolled Zn dendrite formation, poor electrolyte durability, and difficulties in scalable production. This review first elucidates the underlying electrochemical mechanisms of aqueous zinc-ion batteries (AZIBs) and subsequently provides a comprehensive overview of the fabrication strategies employed for constructing fiber-based flexible architectures. Subsequently, recent progress in performance enhancement strategies is comprehensively discussed, with emphasis on cathode material design, anode structure engineering, and gel electrolyte optimization. Finally, key challenges and future directions for FFZIBs are highlighted, emphasizing structural design, material and electrolyte optimization, interfacial regulation, and encapsulation, which are critical for their practical use in wearable energy systems.