Double-shelled hollow microspheres of LiMn2O4 for high-performance lithium ion batteries

Abstract

Double-shelled hollow microspheres of LiMn₂O₄ were prepared by a facile self-template method. The inner and outer shells of the obtained microspheres are composed of nanoparticles with diameters ranging between 200–400 nm. Galvanostatic charge/discharge cycling shows that this material delivers a discharge capacity of 127 mAh g⁻¹ at C/10 rate and a capacity retainability of 80% after 800 cycles at 5 C rate, revealing a high reversible capacity, superior rate capability and excellent cycling stability under high rates. The improved performance is attributed to the short Li⁺ ion diffusion lengths in the nanobuilding blocks and the void core and space between the inner and outer shells to accommodate the volume expansion/contraction during Li⁺ ions insertion/extraction processes.