High‐Performance Yarn Supercapacitor Based on Metal–Inorganic–Organic Hybrid Electrode for Wearable Electronics

Abstract

AbstractA flexible all‐solid‐state yarn supercapacitor (YSC) based on metal–inorganic–organic ternary hybrid structure is fabricated by assembling polypyrrole@manganese oxide nanosheets@stainless steel yarn (PMS) yarn electrode of core/sheath/sheath configuration. The PMS yarn electrode combines the advantages of each component and shows excellent electrochemical performance, mechanical flexibility, and flame retardance owing to its unique structure and synergistic effect. The as‐fabricated YSC exhibits a high areal specific capacitance of 181 mF cm−2, areal energy density of 16.1 µWh cm−2, and areal power density of 10.3 mW cm−2. Moreover, the device possesses desirable voltage/current scalability and outstanding mechanical stability, which maintains 95.8% capacitance retention after 1000 bending cycles. As a demonstration, four YSCs are connected in series and then charged for 10 s to drive a light‐emitting diode (LED) digital watch. The outstanding overall performance of the YSC indicates that it is an ideal flexible power source for safe wearable electronics.