Simulation Of Gravimetric Capacity, Structural And Electronic Properties Of Vanadium Disulphide As Anode Material For Lithium-Ion Bettery

ABSTRACT

Various energy sources are utilized at present with a challenge of energy storage in

many cases. The existing rechargeable storage batteries which include sodium-ion and

lithium-ion have some limitations in their gravimetric capacities. This can be

improved by incorporating Vanadium disulphide (VS2) due to its metallic properties

at ground state. In this work we investigate the adsorption of lithium ions on the VS2

layered material. Research shows that intercalating lithium ions on a monolayer VS2

leads to a high energy capacity anode material but this has faced a challenge in

obtaining the monolayer slab experimentally. For this reason, the ab-initio method

based on density functional theory (DFT) was used to investigate the adsorption of

lithium ions on layered Vanadium disulphide with no bonds in the positive electrode

being broken. All calculations were done within the DFT framework and a plane wave

basis set as implemented in Quantum Expresso code. The projector augmented wave

(PAW) pseudo potentials were used to describe the electron-electron interaction.

From the calculation H-phase monolayer VS2 was found to be stable at room

temperature maintaining the hexagonal structure. Also pure and lithium adsorbed VS2

was found to be electronically stable with zero band gap thus the metallic state is

maintained upon intercalation. VS2 gives a maximum gravimetric capacity of

466mhA/g showing that it offers a more favorable adsorption sites for lithium atoms.

With the structural and electronic stability of VS2 coupled with a high gravimetric

capacity, VS2 is an effective anode material for a high storage capacity lithium ion

battery. Thus can be applied in electrical devices.