Twin-Graphene:\nA Promising Anode Material for Lithium-Ion\nBatteries with Ultrahigh Specific Capacity

Abstract

Lithium-ion batteries have long been the focus of energy\nstorage.\nThe potential application of carbon-derived structures as lithium-ion\nbattery anodes was examined using the first-principles density functional\ntheory approach. The results of our calculations revealed that the\nmodified lattice constant, structure, and parameters are similar to\nthose found in earlier research. It is worth noting that the twin-graphene\ndouble layer has several stable adsorption sites for lithium. Meanwhile,\nwe discovered that the characteristics of semiconductors of pristine\ntwin-graphene changed into metal properties after absorbing lithium.\nFrom climbing image nudged elastic band calculations, we got a medium\ndiffusion barrier of 0.42 eV for lithium ion on twin-graphene, which\ndenotes strong diffusivity. Therefore, it has an ultrahigh theoretical\ncapacity of 3916 mAh/g, about 5 times that of graphene (744 mAh/g).\nTwin-graphene double-layer lithium-ion batteries have an average open\ncircuit voltage of 0.32 V, which ensures long service life and quick\ncharging in practical applications. The relatively good conductivity\nand stability of the twin-graphene double layer are further demonstrated\nthroughout the charge–discharge operation. By reason for the\nforegoing, twin-graphene double layers will be excellent battery anodes\nthat can be applied.