Copolymerization-Assisted Preparation of Porous LiMn2O4 Hollow Microspheres as High Power Cathode of Lithium-ion Batteries

Porous LiMn2O4 hollow microspheres were facilely prepared by incorporation of Li and Mn elements into a spherical polymeric precursor through copolymerization of lithium and manganese acetates with resorcinol and hexamethylenetetramine and then burning off the organic matrix at appropriate temperatures in air. The LiMn2O4 inherited the spherical morphology of the polymeric precursor but showed hollow porous structure assembled by nanocrystals of about 50-100 nm in size. When tested as cathode of Li-ion batteries, the LiMn2O4 hollow spheres exhibited excellent rate capability and cycle stability. A discharge capacity of above 90 mAh g−1 was maintained at 10 C (1 C = 120 mA g−1), and the cells can still deliver a discharge capacity over 100 mAh g−1 after another 115 cycles at 0.5 C. With such excellent electrochemical properties, the prepared LiMn2O4 hollow microspheres could be promising cathode of Li-ion batteries for long term and high power applications.