Intermolecular Stabilization Enables Long-Life, Low-Temperature-Resilient Amino-Anthraquinone Anodes for Sodium-Ion Batteries.

Abstract

Organic electrode materials (OEMs) are promising for sodium-ion batteries but often suffer from dissolution and poor durability. We report a bis-anthraquinone anode, DABT, in which amino groups lower the redox potential and form hydrogen bonds to suppress dissolution. DABT delivers ∼245 mAh g^-1 at an average voltage of ∼1.54 V, with an initial Coulombic efficiency of 98% and 79% capacity retention after 2500 cycles at 2C. Ex situ characterizations reveal a reversible C═O ↔ C-O conversion, coordinating Na⁺ at four carbonyl sites. Paired with a Na₃V₂(PO₄)₃ cathode, the full cell achieves 160 mAh g^-1 at 0.5C with an average voltage of ∼1.5 V, retaining >60% capacity after 500 cycles at 5C. Notably, the DABT//Na₃V₂(PO₄)₃ full cell retains 84% capacity at -20 °C after 100 cycles, underscoring robust low-temperature performance. This study provides a concise molecular-engineering strategy for high-performance organic anodes and advances the practical deployment of SIBs.