A self-healable and highly stretchable supercapacitor based on a dual crosslinked polyelectrolyte

TLDR

Superior self‑healing and stretchability are essential for wearable electronics, yet conventional polyvinyl alcohol electrolytes lack both properties, limiting supercapacitor performance. The study aims to develop a dual‑crosslinked polyacrylic acid electrolyte with vinyl hybrid silica nanoparticles to overcome these limitations. The electrolyte is formed by hydrogen‑bonding and vinyl crosslinking of polyacrylic acid with silica nanoparticles, and a facile electrode fabrication process enables the device to stretch up to 600 %. The resulting supercapacitors are fully self‑healable, maintaining capacitance after 20 break‑heal cycles, and exhibit enhanced performance while sustaining up to 600 % strain.

Abstract

Abstract Superior self-healability and stretchability are critical elements for the practical wide-scale adoption of personalized electronics such as portable and wearable energy storage devices. However, the low healing efficiency of self-healable supercapacitors and the small strain of stretchable supercapacitors are fundamentally limited by conventional polyvinyl alcohol-based acidic electrolytes, which are intrinsically neither self-healable nor highly stretchable. Here we report an electrolyte comprising polyacrylic acid dual crosslinked by hydrogen bonding and vinyl hybrid silica nanoparticles, which displays all superior functions and provides a solution to the intrinsic self-healability and high stretchability problems of a supercapacitor. Supercapacitors with this electrolyte are non-autonomic self-healable, retaining the capacitance completely even after 20 cycles of breaking/healing. These supercapacitors are stretched up to 600% strain with enhanced performance using a designed facile electrode fabrication procedure.