Vanadium oxide nanosheets for flexible dendrite-free hybrid Al-Li-ion batteries with excellent cycling performance

• Main Authors: Gong, Xuefei, Chen, Jingwei, Li, Shaohui, Mohrhusen, Lars, Al-Shamery, Katharina, Lee, Pooi See
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2020
• Subjects: Science::Chemistry; Dendrite-free; Kinetics
• Online Access: https://hdl.handle.net/10356/138676
• Institution: Nanyang Technological University

Aluminum (Al)-ion batteries can be an attractive alternative to lithium-ion batteries because of low costs, high volumetric capacities and dendrite-free formation when Al is used as anode. However, there are limited cathode materials for Al-ion batteries that can deliver satisfactory electrochemical performance, especially cycling stability. The major reason for that is the sluggish kinetics of ion intercalation/deintercalation, resulting from large coulombic attraction between Al3+ and cathodes. Herein, a concept of hybrid Al-Li-ion batteries is proposed to circumvent the poor Al3+ ions insertion/extraction kinetics in Al-ion batteries, and maintain the dendrite-free characteristics of Al-ion batteries. The high volumetric capacity (32.5 mAh/cm3 at 100 mA/cm3, based on the total volume of cathode), enhanced rate capability (21.5 mAh/cm3 at 1000 mA/cm3) and excellent cycling performance (70.1% retention after 3000 cycles) have been achieved in the hybrid Al-Li-ion battery composed of vanadium oxide nanosheets on carbon fibers as cathode and Al as anode in a mixed [EMIM][Cl]/AlCl3/LiCl electrolyte. Combining with the good flexibility of cathode and anode, the hybrid Al-Li-ion battery maintains structural and capacity stability under different bending angles. This study unveils a safe, cost-effective and flexible hybrid Al-Li-ion battery that presents highly competitive advantages among various energy storage devices.