Multifunctional supramolecular gel polymer electrolyte for self-healable and cold-resistant supercapacitor

Self-healability and cold-resistance will greatly improve the reliability of an energy-storage device in case of physical damage and subzero environment, which bring higher and higher requirement to electrolyte. Herein, a multifunctional supramolecular gel polymer electrolyte is prepared, which includes the first cross-linking network between PVA and TA through hydrogen bond cross-linking, and the second PVA network via the freezing-thawing cycle. The synergistic effects of two networks endow the gel polymer electrolyte with outstanding mechanical properties such as high tensile strengths (1.19 MPa), elongations (18.35 mm mm −1 ), self-recovery and excellent self-healability. Moreover, a high conductivity of gel polymer electrolyte is also obtained. A supercapacitor based on the gel polymer electrolyte can significantly restore its electrochemical performances after 10 cutting-healing cycles without external treatment at room temperature. In addition, the supercapacitor presents great controllability and can be tailored into different patterns without property deterioration. Besides, even at −20 °C, the SC is able to maintain 68.3% of its room temperature capacitance. The investigation offers a facile and versatile strategy to construct an intrinsically self-healable and cold-resistant energy-storage device which has potential applications for portable and wearable electronics, smart apparels or flexible robots, and so on.