Stretchable all-in-one supercapacitor enabled by poly(ethylene glycol)-based hydrogel electrolyte with low-temperature tolerance
Yuanyuan Chen, Hailan Ren, Dan Rong, Yujia Huang, Sijing He, Qinfeng Rong
Abstract
Hydrogel electrolytes are crucial components of stretchable energy storage devices due to their flexibility and excellent ion transport ability. However, most hydrogels lose their stretchability in subzero-temperature environments. Herein, a stretchable all-in-one supercapacitor that can work at low temperatures was developed by designing an anti-freezing polyacrylic acid (PAA) hydrogel incorporated with polyethylene glycol (PEG)/H 2 O solvent. PEG endowed the hydrogel with anti-freezing property while avoiding the instability of low-molecular organic solvents . The all-in-one supercapacitor was prepared through the in-situ polymerization and deposition of polyaniline on the faces of the anti-freezing hydrogel electrolyte. The obtained supercapacitor exhibited high capacitive performance, good stretchable capacity, and excellent cycling stability. Moreover, benefiting from the outstanding low-temperature tolerance capacity, the all-in-one supercapacitor can maintain an area specific capacitance of over 63.1% even at −25 °C. This work presents an innovative polymer-solvent system for developing an anti-freezing stretchable all-in-one configured supercapacitor for use as a portable energy storage device in wearable electronics.