3D Patternable Supercapacitors from Hierarchically Architected Porous Fiber Composites for Wearable and Waterproof Energy Storage

High-performance wearable supercapactors (SCs) are gaining prominence as portable energy storage devices. To further enhance both energy and power density, the significant relationship between structure and performance inspires a delicate design of 3D patternable supercapacitors with a hierarchical architecture of porous conductive fibers composited with pseudocapacitive materials. In this work, the polypyrrole nanowires arrays decorated 3D graphite felt fiber assembly is initially fabricated as the conductive scaffold, followed by the distribution of the highly conductive and pseudocapacitive NiCoSe2 nanoparticles. Moreover, to realize the goal of standardized batch and pattern processing of the wearable SCs, laser engraving and silicone sealing techniques are employed, and SC devices with different patterns are successfully fabricated and encapsulated. Notably, the resulting SCs exhibit both stable electrochemical performance and effective waterproof properties, with the highest specific capacitance of 5.21 F cm-3 (113.36 F g-1 ) at the current density of 0.025 A cm-3 (0.5 F g-1 ), and the highest energy density of 1.09 mWh cm-3 (22.14 Wh kg-1 ) at a power density of 16.5 mW cm-3 (358.7 W kg-1 ).