STUDY AND ANALYSIS ELECTRONIC AND MAGNETIC PROPERTIES OF LINIO2 USING DENSITY FUNCTIONAL THEORY METHOD WITHIN APPLICATION IN LITHIUM-ION BATTERIES

• Main Author: Vensiando, Elvan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/55034
• Institution: Institut Teknologi Bandung

The LiNiO2 material is a kind of transition-metal(TM) layer oxide that attractive in development for the positive electrode of secondary battery because of its characteristic capable to save high density of energy, with applying researched computational based on density functional theory in solving the problem of the many-body problem of the atom within one electron do not interact to the another with input parameter already consider at origin in cyber and output data hopefully can give a meaningful interpretation for the experiment to implement in real-world. The aim of this research is for studying the effect of atoms numbers within Fermi energy 9.4392 eV in the bulk system on space group C2/m monoclinic with lattice parameter a = 5.288 Å, b = 2.767 Å, and c = 5.199Å and Li0.3Ni0.7O2 system for considering electronic characteristic with band structure analysis included in the effect of the numbers atom differences, this effect affect the magnetic characteristic of the system is analyzed based on the density of states and the utilization of this material in the positive electrode in secondary battery Lithium-ion batteries with key performance indicator analysis also compare with experimental result in the literature on the primitive Brillouin zone, therefore, the kind of material can be determined by then. The modelling of material using the methode which is input parameter include in Quantum open source package for research in electronic structure, simulation, and optimization(Quantum ESPRESSO) is done on nano scale that calculate based on first principle concept with effective potential Perdew-Burke-Ernzerhof that use a set of plane wave basis set under command line on Linux operating system and the structure is visualized on X-Window Crystalline Structure and Densities(XCrySDen) to give characteristic structure information on reciprocal space for analyzing suited the pattern of band structure and the plot of functional graph is done one software IGOR that can give an interpretation of the density of states curve, and projected density of state that is carried by the wave for giving information with physical unit from the crystal in conideration after that key performance indicator is analyzed in the system of NCA(Nickel Cobalt Aluminum) due to base structure is equivalent to the LiNiO2 system and It is the kind of Lithium-ion battery that have implemented on electric vehicle then the calculation is done by energy – cutoff variation for giving optimal space to the atoms(minimal energy) and convergent value of K-Point 9 × 11 × 9 all the command is done under Linux terminal by command pw.x to give self-consistency value, projwfc.x and dos.x for giving the density of states and band structure. The main result gives the convergent value of energy – cutoff is 40 Ry and using spin-polarized with subtraction E - Ef in the (gamma)-y-M-A-(gamma) orientation that explains semiconductor characteristic and the orbital is dominated by Li – 2s, Ni – 3d, and O – 2p also there is a strong interaction between suborbital Ni – 3d dan O – 2p by the hybridization between of them on the range -1 eV until 1 eV after that non-symmetrical density of states curve explains the ferromagnetic material of the system(the total magnetic moment is not zero) on the other hand system Li0.3Ni0.7O2 has a symmetrical density of states curve that explains the anti-ferromagnetic. To sum up, this research gives a conclusion that computational material is useful in studying the characteristic band of material that depends on atom numbers based on the first principle concept and give the interpretation scientifically from quantum mechanics realm to give information to the research on the bulk system of crystal monoclinic C2/m LiNiO2 that is kind of magnetic conductor and Li0.3Ni0.7O2 is an antiferromagnetic conductor both of these as the candidate of the positive electrode for Lithiumion host to improve its energy density and minimizing the cost of Lithium-ion batteries.