Figure -Spinel Structure of LiMn2O4 LMO is characterized by a spinel-type structure. The lithium ions occupy the tetrahedral sites while the Mn 3+/4+ ions occupy the octahedral sites in the close-packed oxygen structure as shown in Figure . It is characterized by alternative layers of cubic close-packed oxygen spinel ([Mn2]O4) framework. The Mn 3+ containing layer is present in a 3:1 ratio. The cubic close-packed oxygen array gets stabilized leading to reversible movement of lithium ions. The charging cycle leads to the oxidation of manganese ions from Mn 3+ to Mn 4+ . The major issues encountered by the LMO cathode are the dissolution of manganese into the electrolyte and irreversible phase transitions due to the John Teller distortion of Mn 3+ . This leads to poor cyclic stability .