Electrochimica Acta, Vol.111, 192-199, 2013
Excellent electrochemical performance of porous nanoparticles-constructed granule LiMn2O4 derived from a highly reactive Mn3O4
Porous nanoparticles-constructed granule LiMn2O4 spinel was achieved by a solid-state reaction at a relatively low temperature of 600 degrees C, using a highly reactive Mn3O4 as manganese source, prepared by a precipitation-oxidation process. The granule LiMn2O4, well-crystallized with negligible oxygen deficiency, combines the advantages of nano-structured and bulk materials, exhibiting excellent electrochemical performance and a high tap density of 2.05 g cm(-3). Importantly, its cycling performance, especially at elevated temperatures, compares favorably with that of the doped or surface-coated LiMn2O4 materials reported. Also, it shows superior rate capability and cycling performance to the dispersive nanoparticle LiMn2O4 synthesized under the same conditions. The granule LiMn2O4 exhibits a discharge capacity of 121 mAh g(-1) at a current rate of 1 C (where 1 C = 148 mA g(-1)), and retains a capacity of 103 mAh g(-1) at 15C, showing 85% capacity retention. After 200 cycles at 1C and 25 degrees C, it delivers a capacity of 119 mAhg(-1), retaining 98% of its initial capacity. After 100 cycles at 1-C and 55 degrees C, it shows a capacity of 114 mAhg(-1), preserving 95% of its initial capacity. Due to its excellent electrochemical performance and facile synthesis process adopted, the granule LiMn2O4 can serve as a promising cathode for high-performance Li-ion batteries. (C) 2013 Elsevier Ltd. All rights reserved.