Synthesis and electrochemical properties of LiMn2O4 and LiCoO2-coated LiMn2O4 cathode materials

• Published in: Journal of alloys and compounds 2012-03, Vol.517, p.186-191
• Main Authors: Wang, Hong-En, Qian, Dong, Lu, Zhou-guang, Li, Yong-kun
• Format: Article
• Language: English
• Subjects: Chemical synthesis; Chemistry; Electrochemistry; Electrode materials; Electrodes: preparations and properties; Exact sciences and technology; General and physical chemistry; Oxide materials
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2011.12.079

► Spinel LiMn2O4 with different morphologies have been synthesized. ► LiCoO2-coated LiMn2O4 was prepared by a sol–gel route. ► LiMn2O4 and LiCoO2-coated LiMn2O4 microspheres display much better electrochemical cycling properties than those of LiMn2O4 octahedrons. The synthesis of spinel LiMn2O4 material by a spherical MnO2 precursor route is reported in this paper. Hydrothermal and solid-state reactions were adopted to investigate the effects of synthetic methods on the morphologies and electrochemical characteristics of the LiMn2O4 products, respectively. LiCoO2-coated LiMn2O4 microspheres were also prepared by a sol–gel route based on the as-prepared LiMn2O4 microspheres. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrum (EDX), and inductively-coupled plasma emission spectrograph (ICP-ES). The results show that LiMn2O4 octahedrons can be obtained under hydrothermal conditions while LiMn2O4 microspheres can be prepared by the solid-state reaction. Electrochemical characterization reveals that the resulting LiMn2O4 microspheres and LiCoO2-coated LiMn2O4 microspheres display much better cycling properties than those of LiMn2O4 octahedrons.