A self-healing, high stretchable and wide-temperature tolerance hydrogel electrolyte for high-performance supercapacitor

Abstract

All-solid-state flexible supercapacitors provide favorable conditions for the development of portable and wearable devices. The development of electrolytes with excellent self-healing, mechanical and electrochemical properties have become an effective strategy to address the significant mechanical strain and damage of conventional solid state supercapacitors. Herein, a novel PAM/β-CD/EMIMBF4 hydrogel electrolyte with slide-ring structure and hydrogen bonds was synthesized by copolymerization method. The PAM/β-CD/EMIMBF4 hydrogel exhibits outstanding ionic conductivity ((35 mS cm‐1−1), remarkable self-healing behavior (healing efficiency of 91.3%)) and large tensile strain (over 1000 %). Furthermore, the supercapacitor with PAM/β-CD/EMIMBF4 hydrogel electrolyte has a large specific capacitance (124 F g−1) and maintains 82.9 % of its initial value after 5000 cycles. This study designed a multifunctional hydrogel electrolyte, which provides a promising insight for the development of emerging electronic products with customization functions.