Recent Advances in Gel Polymer Electrolytes for High‐Performance Sodium‐Ion Batteries: Materials Design, Interfacial Engineering, and Prospects: A Review

ABSTRACT Energy storage devices have become more and more popular in recent years. Because sodium is abundant in nature, it is inexpensive to use and can be stored on a big scale. Because sodium‐ion batteries have a greater capacity to support high energy density, they are seen to be a promising substitute for lithium‐ion batteries. Due to the inherent safety requirement, high‐performance electrolytes are necessary for the stability of sodium‐ion batteries. Gel polymer electrolytes (GPEs) offer a great compromise between the benefits of high thermal stability, low interfacial impedance, flexibility, and strong ionic conductivity. With an emphasis on various preparation techniques and the resulting physical and electrochemical properties, this brief review highlights the most recent developments in gel polymer Na‐ion batteries. The molecular level is used to explore the causes of the variations in mechanical, interfacial, thermal, and ionic conductivity characteristics. Finally, the future opportunities and challenges connected with large‐scale commercial manufacture and implementation of advanced GPEs in new energy storage systems are discussed, along with recommendations for their future development.