Twin-Graphene: A Promising Anode Material for Lithium-Ion Batteries with Ultrahigh Specific Capacity

Lithium-ion batteries have long been the focus of energy storage. The potential application of carbon-derived structures as lithium-ion battery anodes was examined using the first-principles density functional theory approach. The results of our calculations revealed that the modified lattice constant, structure, and parameters are similar to those found in earlier research. It is worth noting that the twin-graphene double layer has several stable adsorption sites for lithium. Meanwhile, we discovered that the characteristics of semiconductors of pristine twin-graphene changed into metal properties after absorbing lithium. From climbing image nudged elastic band calculations, we got a medium diffusion barrier of 0.42 eV for lithium ion on twin-graphene, which denotes strong diffusivity. Therefore, it has an ultrahigh theoretical capacity of 3916 mAh/g, about 5 times that of graphene (744 mAh/g). Twin-graphene double-layer lithium-ion batteries have an average open circuit voltage of 0.32 V, which ensures long service life and quick charging in practical applications. The relatively good conductivity and stability of the twin-graphene double layer are further demonstrated throughout the charge–discharge operation. By reason for the foregoing, twin-graphene double layers will be excellent battery anodes that can be applied.