Interfacial crosslinking of hygroscopic hydrogel: A universal strategy for energy storage garment and its wearable applications

Energy storage textiles represent an innovative form of flexible energy storage devices, fully leveraging the wearing advantages of textiles and demonstrating unique benefits in wearable electronics. However, due to the inherent porous and insulating characteristics of textiles, textiles electrodes suffer from intricate preparation process and unsatisfying performance. Additionally, the electrolytes face challenges such as evaporation loss and leakage. To address these issues, this work presents an innovative strategy for fabricating energy storage garments based on the interfacial crosslinking of hydrogel electrolyte. Garments and electrodes were first assembled with polyvinyl alcohol (PVA) solution. The energy storage textiles are prepared by constructing textile/hydrogel/electrode interfaces during the freezing-thawing crosslinking process with enhanced strength. This strategy avoids the complex step of fabricating textile electrodes. Additionally, the hydrogel is hygroscopic and can replenish moisture from the air, enabling the long-term operation of devices without encapsulation. Importantly, this strategy is versatile and compatible with various textiles and available electrodes. A variety of supercapacitors (SCs) have been successfully integrated into commercial garments, including large-sized devices (5 × 5 cm², 11.8 F) for wearable applications. This innovative strategy is expected to provide new insights for the development of energy storage textiles.