An Agar gel modulation with melamine foam skeleton for flexible Zn-air batteries

Flexible zinc-air batteries (FZABs) have excellent application prospects in flexible wearable electronic devices due to their high safety and low cost. However, zinc electrode passivation, low conductivity of the solid-state electrolyte (SSE), and poor mechanical properties severely limit the areal capacity of the FZABs, which is challenging to meet the requirements of flexible electronic equipment for flexible power supply devices. Herein, an environment-friendly Agar gel SSE is prepared for FZABs. To further improve the mechanical strength and electrochemical performance of the Agar-based zinc-air battery, melamine-Agar SSE (M-Agar SSE) is fabricated by introducing melamine foam (M foam) skeleton into Agar gel. Compared with Agar gel electrolyte, the prepared M-Agar SSE delivers essentially improved properties in terms of mechanical strength, water retention capability, and ionic conductivity. Therefore, the FZAB based on the M-Agar SSE can achieve a maximum output power of 126 mW cM-2 and a high areal capacity of 24 mAh cM-2. In addition, the assembled sandwich-type batteries adapt to extreme working conditions without significant electrochemical performance degradation, demonstrating their great potential for flexible wearable devices.