A Bioinspired CNTs-Enhanced Anode for Ultra-Stable Aluminum-Ion Batteries

Aluminum-ion batteries (AIBs) hold great promise for large-scale energy storage owing to their cost-effectiveness. However, Al-metal anodes face challenges such as passivation, dendrites, and structural degradation, thus limiting long-term cycling stability. Inspired by the highly sensitive diffuse nerve net of sea anemone tentacles, a bioinspired Al@CNT anode is rationally designed by incorporating aluminophilic carbon nanotubes (CNTs) into Al matrix. These CNTs form a homogeneous neural-like percolation network, establishing continuous pathways that homogenize charge distribution and strengthen the mechanical adhesion of Al⁰ deposits to the matrix thus inhibiting “dead Al” formation and structural degradation. Consequently, the aluminophilic CNT interface directs uniform and compact Al nucleation with reduced surface roughness and low polarization, stabilizing repeated plating/stripping. Benefiting from the designed composite structure, excellent cycling stability is achieved under aggressive conditions, with Al@CNT-1.0||Al@CNT-1.0 symmetric cells sustaining run beyond 1800 h at 3 mA cm⁻² and 3 mAh cm⁻², while the pure Al||Al cells short-circuited within 170 h. Full cells paired with artificial graphite demonstrate 45 000 stable cycles at 5 A g⁻¹ with over 80% capacity retention when using the Al@CNT-1.0 anode. This work provides a scalable, bioinspired strategy toward dendrite-free, highly stable Al-metal anodes, opening new pathways for practical AIBs energy storage systems.