Pre-Lithiated Li2V6O13 Cathode Enables High-Energy Aluminum-Ion Battery

Owing to the low-cost, safety, and three-electron redox properties of aluminum, rechargeable aluminum-ion batteries (AIBs) are emerging as a promising energy storage technology. However, exploring suitable cathode material with both elevated working voltage and high reversible capacity remains a daunting challenge. Herein, under the guidance of density functional theory calculations, V6O13 is proposed as a promising cathode candidate in AIBs for the first time. It is demonstrated that aluminum ions are reversibly stored in V6O13 by intercalation reactions, with a high discharge voltage plateau of approximate to 1.1 V. Of particular note a pre-lithiation strategy is employed to further promote the redox kinetics, which endows the pre-lithiated V6O13 nanobelt (Li-VONB) with improved capacity of 161.6 mAh g(-1) and impressive energy density of 177.7 Wh kg(-1) after 300 cycles, far higher than other reported oxide cathodes in AIBs. Moreover, the shielding effect of pre-inserted Li and accelerated diffusion rate are uncovered at the atomic scale. This work develops a novel Li-VONB cathode for high-energy AIBs, and shows the great potential of pre-intercalation strategies in the application of AIBs.