High capacity Li2MnSiO4/C nanocomposite prepared by sol-gel method for lithium-ion batteries

A high capacity Li2MnSiO4 (LMS)/C nanocomposite has been prepared by glucose assisted sol-gel method with in situ carbon coating. X-ray diffraction (XRD) measurements confirm the formation of orthorhombic structure with Pmn2(1) space group. Field emission scanning electron microscopy (FESEM) shows that the LMS/C powders consist of uniformly distributed nanoparticles with size in the range of 20 -50 nm and high-resolution transmission electron microscopy (HRTEM) confirms that amorphous carbon coat on the LMS nanocrystals. Electrochemical tests reveal that the LMS/C nanocomposite has a high initial discharge capacity of 253.4 mA h g(-1) at 10 mA g(-1) and superior rate capability (193.1 mA h g(-1) at 160 mA g(-1) and 149.9 mA h g(-1) at 320 mA g(-1)). The improved electrochemical performance is ascribed to coated carbon and nanoparticle size, which can enhance the electronic conductivity as well as lithium-ion diffusion coefficient. (C) 2013 Elsevier B.V. All rights reserved.