High-Performance-Integrated Stretchable Supercapacitors Based on a Polyurethane Organo/Hydrogel Electrolyte.

Stretchable supercapacitors (SSCs) are promising energy storage devices for emerging wearable electronics. However, the low-energy density and poor deformation performance are still a challenge. Herein, an amphiphilic polyurethane-based organo/hydrogel electrolyte (APUGE) with a H 2 O/AN-in-salt (H 2 O/AN-NaClO 4 ) is prepared for the first time. The as-prepared APUGE shows a wide voltage window (∼2.3 V), good adhesion, and excellent resilience. In addition, the intrinsically stretchable electrodes are prepared by coating the activated carbon slurry onto the PU/carbon black/MWCNT conductive elastic substrate. Based on the strong interface adhesion of the PU matrix, the as-assembled SSC delivers high-energy density (5.65 mW h cm -3 when the power density is 0.0256 W cm -3 ) and excellent deformation stability with 94.5% capacitance retention after 500 stretching cycles at 100% strain. This fully integrated construction concept is expected to be extended to multisystem stretchable metal ion batteries, stretchable lithium-sulfur batteries, and other stretchable energy storage devices.