: The development of cathode materials with excellent electrochemical performance is critical for the advancement of lithium-ion batteries (LIBs) in energy storage applications. LiMn2O4 (LMO) is a promising cathode material for LIBs due to its high theoretical capacity, low cost, and environmentally friendly nature. In this study, P. Anbarasi focuses on the synthesis and characterization of LMO-based cathode materials for LIBs. Various synthesis methods, including solid-state synthesis, hydrothermal synthesis, sol-gel synthesis, co-precipitation method, and combustion synthesis, have been employed to prepare LMO cathode materials. The structural characterization of these materials has been carried out using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, surface area analysis, and porosity measurements. The results show that the synthesis method plays a crucial role in determining the morphology, crystallinity, particle size, and surface area of the LMO cathode materials. The electrochemical characterization of LMO cathode materials has been conducted using cyclic voltammetry, galvanostatic charge-discharge cycling, impedance spectroscopy, and other techniques. The electrochemical performance of the LMO cathode materials has been evaluated in terms of capacity retention, rate capability, coulombic efficiency, diffusion coefficient, redox reaction, intercalation/deintercalation, and other parameters. The results demonstrate that LMO cathode materials have excellent electrochemical performance, making them suitable for use in LIBs. Furthermore, the effects of aging mechanisms, thermal stability, safety, environmental impact, and green synthesis on the performance and sustainability of LMO cathode materials have been studied. This research is significant as it provides valuable insights into the synthesis and characterization of LMO cathode materials for LIBs, which will pave the way for the development of efficient and sustainable energy storage systems.