Full‐Active‐Unit Molecular Design Strategy Enabling High‐Capacity and Stable Quinone Organic Cathodes for Lithium‐Ion Batteries

Abstract

ABSTRACT Redox‐active quinones have emerged as promising organic cathode materials (OCMs) for next‐generation lithium‐ion batteries (LIBs). However, their practical application is hindered by rapid dissolution in organic electrolytes and the common molecular design trade‐off where the introduction of non‐active structural motifs diminishes the specific capacity. To address these challenges, we propose a full‐active‐unit molecular design strategy. This approach connects two quinone (9,10‐anthraquinone or 9,10‐phenanthrenequinone) units via C─C single bond to a high‐capacity pyrene‐4,5,9,10‐tetraone core, aiming for both low solubility and high specific capacity. Accordingly, we synthesized 2,7‐bis(9,10‐anthraquinonyl)pyrene‐4,5,9,10‐tetraone (BAPO) and 2,7‐bis(9,10‐phenanthraquinonyl)pyrene‐4,5,9,10‐tetraone (BPPO), both exhibiting low solubility. Electrochemical tests revealed excellent cell performance, particularly for the BAPO cathode, which delivered a high capacity of 317.5 mAh g − 1 at 0.2 C and demonstrated exceptional long‐term cycling stability with 70.2% capacity retention after 9000 cycles at 5 C. This work provides a new molecular design concept for developing quinone cathode materials that simultaneously achieve high capacity and long cycle life.