Superlattice cathodes endow cation and anion co-intercalation for high-energy-density aluminium batteries.

Cui, Fangyan; Li, Jingzhen; Lai, Chen; Li, Changzhan; Sun, Chunhao; Du, Kai; Wang, Jinshu; Li, Hongyi et al. · Nat Commun · 2024

basic_science · Level V

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Abstract

Conventionally, rocking-chair batteries capacity primarily depends on cation shuttling. However, intrinsically high-charge-density metal-ions, such as Al<sup>3+</sup>, inevitably cause strong Coulombic ion-lattice interactions, resulting in low practical energy density and inferior long-term stability towards rechargeable aluminium batteries (RABs). Herein, we introduce tunable quantum confinement effects and tailor a family of anion/cation co-(de)intercalation superlattice cathodes, achieving high-voltage anion charge compensation, with extra-capacity, in RABs. The optimized superlattice cathode with adjustable van der Waals not only enables facile traditional cation (de)intercalation, but also activates O<sup>2-</sup> compensation with an extra anion reaction. Furthermore, the constructed cathode delivers high energy-density (466 Wh kg<sup>-1</sup> at 107 W kg<sup>-1</sup>) and one of the best cycle stability (225 mAh g<sup>-1</sup> over 3000 cycles at 2.0 A g<sup>-1</sup>) in RABs. Overall, the anion-involving redox mechanism overcomes the bottlenecks of conventional electrodes, thereby heralding a promising advance in energy-storage-systems.