Effects of different Ti concentrations doping on Li2MnO3 cathode material for lithium-ion batteries via density functional theory

Abstract

Abstract Li2MnO3 is extensively studied for a cathode material in lithium-ion batteries because of its high voltage and specific capacity. Nevertheless, it has the disadvantages due to low conductivity and Li-ion diffusion. To modify its performance, we determine the structure stability and electronic properties of Li2MnO3 cathodes doped with different Ti-ion concentrations using the spin-polarized density functional theory including the Hubbard term (DFT + U). For the calculations, cell parameters, formation energies, band gaps, total density of states, partial density of states and stability voltages are determined. The results highlight that the expansion of the cell volumes by Ti-ion impurities has a positive effect on the diffusion of Li ions in these cathodes. Because of the minor voltage changes, Li2MnO3 cathode doped with a Ti-ion concentration of 0.250 exhibits the highest voltage stability. Overall, these results are effective for the lithium-ion battery application based on Ti-doped Li2MnO3 cathodes.