Abstract:Hydrogels have plentiful insights and opportunities in flexible and wearable fields due to their excellent flexibility, ion transport, and adjustable mechanical properties. However, hydrogel electronic devices are prone to freeze in cold climate, which severely limits the application potential of hydrogel electronic materials in cold environments. By introducing cryoprotectants into hydrogels, the anti-freezing properties of hydrogels can be endowed and the working temperature of hydrogels electronic devices also can be broadened. In this review, the preparation methods and freeze-tolerance mechanisms of anti-freezing hydrogels in recent years were summarized from the aspects of solute ions, ionic liquids, organic solvents or antifreeze proteins-modified hydrogels. Furthermore, the application progress of anti-freezing hydrogels in flexible electronics such as the supercapacitor, sensor, and battery were expounded thoroughly, and their problems and challenges were concluded. Finally, the development trend of anti-freezing hydrogel electronic materials was prospected, and it was pointed out that the utilization of natural raw materials in the exploration of anti-freezing hydrogels with excellent mechanical properties, electrochemical performances, bionontoxicity, biocompatibility and biodegradability will become the focus of further research, while the design optimization of flexible electronic devices, the improvement of the safe reliability of devices, and the output stability will be also an important research direction. The preparations and applications of anti-freezing hydrogels will promote the rapid development of flexible electronic functional materials.