Heterocyclic Conjugated Polymer Nanoarchitectonics with Synergistic Redox‐Active Sites for High‐Performance Aluminium Organic Batteries

Abstract The development of cost‐effective and long‐life rechargeable aluminium ion batteries (AIBs) shows promising prospects for sustainable energy storage applications. Here, we report a heteroatom π‐conjugated polymer featuring synergistic C=O and C=N active centres as a new cathode material in AIBs using a low‐cost AlCl 3 /urea electrolyte. Density functional theory (DFT) calculations reveal the fused C=N sites in the polymer not only benefit good π‐conjugation but also enhance the redox reactivity of C=O sites, which enables the polymer to accommodate four AlCl 2 (urea) 2 + per repeating unit. By integrating the polymer with carbon nanotubes, the hybrid cathode exhibits a high discharge capacity and a long cycle life (295 mAh g −1 at 0.1 A g −1 and 85 mAh g −1 at 1 A g −1 over 4000 cycles). The achieved specific energy density of 413 Wh kg −1 outperforms most Al–organic batteries reported to date. The synergistic redox‐active sites strategy sheds light on the rational design of organic electrode materials.