Development of High-Performance Large-Scale Structural Supercapacitors via the Resin Infusion Process and Encapsulation Process

Large-scale structural supercapacitors (SSCs) are gaining attention as a promising energy storage option for electric vehicles and renewable energy due to their robustness and large storage capacity. Current manufacturing methods frequently yield unstable thin films with inconsistent size and thickness, hindering their industrial-scale viability. This study showcases a resin infusion (RI) process that produces large-sized SSCs, enhancing the uniformity, electrochemical performance, and mechanical properties. Woven carbon fibers with activated carbon coatings serve as electrodes, with a glass fiber dielectric layer acting as both a separator and reinforcement for mechanical strength. An epoxy PVA/KOH-based electrolyte is fabricated using the RI process. It is found that an electrolyte with a resin content ranging from 15 to 40 wt % achieves a balanced performance in terms of both electrochemical and mechanical properties. The 100 x 100 mm(2) area of an SSC with 15 wt % resin demonstrates the highest specific capacitance of 12.60 F/g, specific energy of 0.646 Wh/kg, and specific power of 0.031 kW/kg. Moreover, encapsulating the SSCs with prepreg glass fiber significantly prolongs the lifespan of the device, maintaining 87.3% of the initial capacitance after 7 days. This study advances SSC fabrication processes, facilitating their immediate scaling to an industrial level and broadening their applicability in real-world industrial and market scenarios.