Recent progress and future perspectives of flexible Zn-Air batteries

With the booming of flexible and wearable electronic devices, demands for compatible power supply devices with high energy density and safety, excellent flexibility for superior comfort, as well as compact structure to drive these wearable electronic devices are increased rapidly. Rechargeable solid-state flexible Zn-air battery (F-ZAB) is considered as one of the most competitive and promising energy storage system because of its high energy density, intrinsic safety, and flexible mechanical properties. In recent years, although cathode electrocatalysts have made great progress in improving the electrochemical properties of F-ZABs, the mechanical flexibility and durability of F-ZABs for wearable application still face many technical challenges. Moreover, with the miniaturization of wearable electronic devices, the on-chip integrability of F-ZABs is also needful. To maintain the balance among electrochemical properties, flexibility and integrability of F-ZABs, efficient catalyst, durable electrode, high conductivity and flexible electrolyte, and reasonable battery configuration are crucial. In this article, the latest advances and challenges of F-ZABs exploration are introduced though a detailed review of the battery components including the air electrode, Zn electrode, solid-state electrolyte, and the battery configuration. Meanwhile, challenges facing the development of F-ZABs are highlighted together with the discussion of further research directions and perspectives.