Lithium manganese oxide (LMO, CAS number 12057-17-9) has a chemical formula of LiMn2O4 is also referred to as lithium manganate. It is a promising candidate to replace layered Ni or Co oxide materials as the cathode in lithium-ion batteries. Known for its intrinsic low-cost, environmental friendliness, high abundance, and better safety, lithium manganese oxide can improve ion transport and power capability especially at high rates. It also has a higher nominal voltage (4.0 V) than the benchmark cathode material LiCoO2.

Like LiCoO2, LiMn2O4 suffers from capacity fading caused by a combination of structural transformation and transition metal cation dissolution. The so called Jahn–Teller distortion, occurred at the discharge state of Mn3+, causes a symmetry distortion of the octahedra complex and transforms the spinel into a tetragonal with large anisotropic volume change. The structure distortion is peaked at high current rate when Li+ diffusion rate into the electrolyte is greater than inside the domain of the crystal structure.