Comparing the behavior of nano- and microsized particles of LiMn _1.5Ni_0.5O₄ spinel as cathode materials for li-ion batteries

We report on a rigorous comparative study of nano- and microparticles of Li Mn1.5 Ni0.5 O4 spinel as cathode materials for Li-ion batteries. The stability of these materials in LiP F6 /alkyl carbonate solutions in temperatures up to 70°C was explored. Capacity, cycling, rate capabilities, and impedance behavior were also studied. The methods included X-ray diffraction, Raman, X-ray photelectron, Fourier transform infrared, and electron paramagnetic resonance spectroscopies, and electron microscopy, in conjunction with standard electrochemical techniques: voltammetry, chronopotentiometry, and impedance spectroscopy. These materials show an impressive stability in solutions at elevated temperature. The use of nanomaterials was advantageous for obtaining a better rate capability of Li Mn1.5 Ni0.5 O4 electrodes. Li Mn1.5 Ni0.5 O4 particles develop a unique surface chemistry in solutions that passivates and protects them from detrimental interactions with solution species at elevated temperatures.