A Three-Dimensional Points–Lines–Planes Interweaved Conductive Additive with Ultrahigh Electron Transfer for High-Performance Supercapacitors

Conductive additives play a crucial role in the electrochemical performance of supercapacitors, particularly in the delivery of energy under high-power conditions. A three-dimensional supercapacitor composite conductive additive, 3D-ACET-CNT-MXene (3D-ACM-1), has been successfully developed in this study by combining traditional conductive additives acetylene black (ACET) and CNT@MXene materials. In this structure, ACET acts as the conductive active site; CNT serves as the connecting conductive network between ACET and MXene; and MXene sheets function as the conductive plane, providing loading sites for ACET particles. These three components synergistically form a three-dimensional conductive network composed of points, lines, and planes. This three-dimensional conductive network effectively facilitates electron transfer and promotes electrochemical reactions, significantly enhancing the rate capability of the electrode material at high current densities. While ensuring the highest conductivity, 3D-ACM-1 controls smaller production costs compared to the pricier ECP-600JD material. Importantly, 3D-ACM-1 effectively addresses the dispersion issues of MXene in organic phases and dry electrode preparation. It can directly replace commercial conductive additives in coating processes for industrial electrode materials without any alterations. Therefore, this work holds significant importance for the manufacturing of low-cost, high-performance supercapacitor products.