Multi-Ionic Capacity of Zn-Al/V6O13 Systems Enable Fast-Charging and Ultra-Stable Aqueous Aluminium-Ion Batteries

초록

Rechargeable, cost-efficient aqueous aluminium-ion batteries (AAIBs) possess abundant trivalent charge carriers with high volumetric energy densities. However, the rapid and irreversible formation of Al2O3 passivation films on aluminium-ion (AI) anodes while using aqueous electrolytes limits their development. Herein, Zn metal was used as the anode, and Al3+ was locally deposited on the Zn anode during charging. V6O13 with a mixed vanadium state of V4+/V5+ was chosen as the cathode because of its efficient ion diffusion (solid state) and high electron conductivity. The Zn-Al/3 M Al(OTF)(3)/V6O13 cell exhibited high current density and excellent long-term cycling stability, demonstrating a very high specific capacity of similar to 100 mAh g(-1) at a current density of 3 A g(-1) and Coulombic efficiency of similar to 100 % with reversible stability over 1400 cycles. Furthermore, the V6O13 cathode exhibited a multi-ionic capacity of Zn2+- and H+-ions during the Al deposition/dissolution reaction in AAIBs, demonstrating high safety and stability for fast charging.

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