Structural, Electronic, and Magnetic Properties of Li_1+xMn₂O₄ Based on First-Principles Calculations

Recent studies have focused on understanding the reaction mechanisms driven by the lithiation of Li_1+xMn₂O₄ spinels, in an effort to enhance the energy density of lithium-ion batteries. Experiments to characterize the spinels’ fundamental properties during the reaction are challenging. Thus computational/theoretical modeling is highly desirable. In this study, we identified global/local minimum structures of Li_1+xMn₂O₄ spinels by using a global structure optimization algorithm coupled with first-principles calculations, and further characterized their basic electronic and magnetic properties, as well as their relative structural stabilities under external perturbations. Interestingly, the local Jahn–Teller distortion was found to play a governing role in determining spinels’ relative stabilities, in comparison to other key factors such as charge states of the Mn ions, positions of the Li ions, and magnetic configurations. Feasible pathways for the experimental verification of lithiation are proposed.