Carbon fiber reinforced epoxy composite combining superior electrochemical energy storage and mechanical performance

Sophisticated power systems of unmanned aerial vehicles (UAVs) are comprised of multiple subcomponents, which each typically perform unique functions. Combining these functions into an integrated component could enhance durability and improve overall systematic efficiency. Particularly, creating structural materials combining superior energy storing capacity and mechanical properties could provide significant weight savings and endurance strengthening for electric power systems of UAVs. Herein, a highly integrated composite that could efficiently store energy and withstand mechanical loads was intelligently designed and manufactured. The structural energy storage composites (SESCs) consisted of high-strength carbon fiber, high-dielectric epoxy resin and as-synthesized pollution-free zinc-ion batteries (ZIBs). In particular, the epoxy resin acts as both the polymer matrix of carbon fiber reinforced composites, and also the enhanced packaging materials for the energy storage component. Remarkably, the SESCs exhibited high specific capacity, large energy density and long cycle life. Specifically, the energy density of the SESCs reached 115.2 Wh kg−1, and the specific capacity could still maintain 61.7 mAh g−1 after 500 cycles. In addition, the SESCs possessed superior mechanical properties. The tensile modulus and flexural modulus of the SESCs were 10.0 GPa and 12.1 GPa, respectively. Furthermore, the mechano-electrochemical analysis indicated that it could still maintain a discharge specific capacity of 28.5 mAh g−1 under the tensile stress of 120 MPa, and its multifunctional efficiency could reach 1.27. This study provided an effective approach to design and manufacture electric power systems integrating lightweight and high-durability properties for next-generation UAVs.