Tetramethylguanidine‐Modified Graphene Oxide as a Gel Polymer Electrolyte Additive for Improving the Performance of Flexible Zinc‐Air Batteries

Abstract Flexible zinc‐air batteries (FZABs) present a promising solution for the next generation of power sources in wearable electronics, owing to their high energy density, cost‐effectiveness, and safety. However, solid‐state electrolytes for FZABs continue to face challenges related to rapid water loss and low ionic conductivity. In this study, a hydrophilic and stable tetramethylguanidine‐modified graphene oxide as an additive, which is incorporated into sodium polyacrylate to develop a high‐performance gel polymer electrolyte (GPE), is designed. The addition of additives makes GPE more hydrophilic, allowing for a wider hydrogen bonding network and more efficient ion transport channels. Due to its stable structure, abundant water channels and fast OH − conductivity, GPE also offers excellent mechanical properties, long‐lasting water retention, and high ionic conductivity (173.9 mS cm −1 ). FZABs assembled with this GPE exhibit a high open‐circuit voltage of 1.558 V, a cycle life of 230 h, a specific capacity of 810.3 mAh g −1 , and a peak power density of 130.5 mW cm −2 , coupled with impressive flexibility. These characteristics underscore their significant potential for applications in wearable electronics.