Four LiMn0.8Fe0.1M0.1PO4/C (M = Fe, Co, Ni, Cu) cathode materials have been synthesized via a freeze-drying method. The samples have been characterized by powder X-ray diffraction, transmission electron microscopy, magnetic susceptibility, and electrochemical measurements. The composition and effective insertion of the transition-metal substituents in LiMnPO4 have been corroborated by elemental analysis, the evolution of the crystallographic parameters, and the magnetic properties. The morphological characterization of the composites has demonstrated that the phosphate nanoparticles are enclosed in a matrix of amorphous carbon. Among them, LiMn0.8Fe0.1Ni0.1PO4/C is the most promising cathode material, providing a good electrochemical performance in all aspects: high voltage and specific capacity values, excellent cyclability, and good rate capability. This result has been attributed to several factors, such as the suitable morphology of the sample, the good connection afforded by the in situ generated carbon, and the amelioration of the structural stress provided by the presence of Ni2+ and Fe2+ in the olivine structure.
AD -Departamento de Quimica Inorganica, Universidad del Pais Vasco UPV/EHU , P.O. Box 644, 48080 Bilbao, Spain.
AN - 25723381 BT - Inorganic Chemistry DA - 02/2015 DO - 10.1021/ic5028306 ET - 2015/02/28 IS - 6 J2 - Inorganic chemistry LA - eng M1 - 6 N2 -Four LiMn0.8Fe0.1M0.1PO4/C (M = Fe, Co, Ni, Cu) cathode materials have been synthesized via a freeze-drying method. The samples have been characterized by powder X-ray diffraction, transmission electron microscopy, magnetic susceptibility, and electrochemical measurements. The composition and effective insertion of the transition-metal substituents in LiMnPO4 have been corroborated by elemental analysis, the evolution of the crystallographic parameters, and the magnetic properties. The morphological characterization of the composites has demonstrated that the phosphate nanoparticles are enclosed in a matrix of amorphous carbon. Among them, LiMn0.8Fe0.1Ni0.1PO4/C is the most promising cathode material, providing a good electrochemical performance in all aspects: high voltage and specific capacity values, excellent cyclability, and good rate capability. This result has been attributed to several factors, such as the suitable morphology of the sample, the good connection afforded by the in situ generated carbon, and the amelioration of the structural stress provided by the presence of Ni2+ and Fe2+ in the olivine structure.
PY - 2015 SN - 1520-510X (Electronic) 0020-1669 (Linking) EP - 2671–2678 ST - Inorg Chem T2 - Inorganic Chemistry TI - High-Voltage Cathode Materials for Lithium-Ion Batteries: Freeze-Dried LiMn0.8Fe0.1M0.1PO4/C (M = Fe, Co, Ni, Cu) Nanocomposites VL - 54 ER -