Design and Fabrication of AC&GO Carbon-Fiber Structural Supercapacitor with Balanced Mechanical and Electrochemical Properties

With the rapid advancements in global electric aircraft and energy storage, the integration of carbon-fiber composite structures with energy storage technology has become a prominent topic. An AC&GO carbon fiber structural supercapacitor is designed by integrating the high specific surface area of AC with the excellent mechanical properties of GO, achieving a balanced mechanical and electrochemical performance. This supercapacitor exhibits high stability in charge–discharge characteristics, showing a capacitance of 75.79 mF cm −2 at a current density of 0.05 mA cm −2 and an energy density of 236.85 mWh m −2 . In addition, the maximum power density is 22.59 W m −2 at a current density of 1 mA cm −2 . The capacitance retention and coulombic efficiency are 98.99% and 96.52%, respectively, after 10 000 charge–discharge cycles at a current density of 0.2 mA cm −2 . Furthermore, after 15 000 cycles under load-bearing and tensile conditions at a current density of 0.2 mA cm −2 , the capacitance retention is 98.52% and 93.05%, respectively, with the tensile strength remaining above 90% compared with non-energy storage components. The multifunctional efficiency reaches 1.28, indicating the mechanical load bearing and electrochemical energy storage of AC&GO, thereby demonstrating its application potential in aerospace.