First principle study on the application of crystalline cathodes Li2Mn0.5TM0.5O3 for promoting the performance of lithium-ion batteries

A representation of priority properties of the cathodes: Li2Mn0.5Ni0.5O3(LMNO), Li2Mn0.5Co0.5O3(LMCO), Li2Mn0.5Fe0.5O3(LMFO) and Li2MnO3(LMNO) affecting the performance of Lithium-ion batteries (LIBs). [Display omitted] In this work the transition metals Fe, Co and Ni are selected for doping into Lithium manganese oxide Li2MnO3 (LMO), to form the doped cathodes with general formula of Li2Mn0.5TM0.5O3 and then examine their properties in order to determine which doped cathode would manifest the most efficient performance, if used in lithium ion batteries (LIBs). For this purpose, the spin-polarized density functional theory (DFT) method is employed to calculate the cathodes’ properties such as voltage, density of states (DOSs) related to electronic states of the cathodes, energy barrier of these cathodes against Li+ transfer through the cathodes and free energy change as result of phase transition followed by oxygen removal due to occurrence of electrochemical reaction in the cathodes. Inspecting the obtained results indicates that, the doped cathodes Li2Mn0.5Ni0.5O3 (LMNO) and Li2Mn0.5Co0.5O3 (LMCO) manifest the most desirable performance compared with the doped Li2Mn0.5Fe0.5O3 (LMFO) and undoped Li2MnO3 (LMO) cathodes. Finally, considering the overall results with emphasize on two properties, namely, feasibility of Li+ transfer through the cathodes and prevention of phase transformation due to oxygen removal in the cathodes, are led to the conclusion that, LMNO can be proposed as the most effective cathode for utilization in the LIBs.