Superlattice cathodes endow cation and anion co-intercalation for high-energy-density aluminium batteries
Fangyan Cui, Jingzhen Li, Chen Lai, Changzhan Li, Chunhao Sun, Kai Du, Jinshu Wang, Hongyi Li, Aoming Huang, Shengjie Peng, Yuxiang Hu
Abstract
Conventionally, rocking-chair batteries capacity primarily depends on cation shuttling. However, intrinsically high-charge-density metal-ions, such as Al3+, 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 O2– compensation with an extra anion reaction. Furthermore, the constructed cathode delivers high energy-density (466 Wh kg–1 at 107 W kg−1) and one of the best cycle stability (225 mAh g–1 over 3000 cycles at 2.0 A g–1) in RABs. Overall, the anion-involving redox mechanism overcomes the bottlenecks of conventional electrodes, thereby heralding a promising advance in energy-storage-systems. Here, the authors propose a superlattice cathode with co-(de)intercalation chemistry in a rechargeable aluminum ion battery. The proposed cathode exceeds the theoretical capacity for conventional oxide electrodes with single cation shuttling.