Recent progress in the All-Gel-State supercapacitors

Supercapacitors (SCs) are promising energy storage devices for flexible electronics by virtue of the high power density, exceptional cycle life, and low maintenance cost. Typically, all-gel-state SCs based on conductive hydrogels (CHs) make a splash on account of their simplified configuration, remarkably flexibility, inherent deformation tolerance and diminished interfacial impedance. Herein, a comprehensive overview of the cutting-edge advances in all-gel-state SCs is provided, involving the fabrication strategies, multifunctionality, different configurations and perspectives. The fabrication strategies are systematically introduced, encompassing the assembly of CH-based electrodes and electrolytes and the in-situ deposition of electroactive materials on CH-based electrolytes. Subsequently, the multifuntional all-gel-state SCs are emphasized, such as highly stretchable and compressible, self-healing, and anti-freezing devices. Furthermore, sorts of configurations of all-gel-state SCs, comprised of 1D fiber-shaped and 2D planner structures, are represented. Last but not the least, the challenges and opportunities of such attractive all-gel-state SCs are concluded, navigating the advancement of flexible power electronics.