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LiFePO₄ nanocrystals were synthesized in various polyol media without any further post-heat treatment. The LiFePO₄ samples synthesized using three different polyol media namely, diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (TTEG), exhibited plate and rod-shaped structures with average sizes of 50–500 nm. The X-ray diffraction (XRD) patterns were indexed on the basis of an olivine structure (space group: Pnma). The samples prepared in DEG, TEG, and TTEG polyol media showed reversible capacities of 123, 155, and 166 mAh/g, respectively, at current density of 0.1 mA/cm² with no capacity fading and exhibited excellent capacity retention up to the 50th cycle. In particular, the samples showed excellent performances at high rates of 30 and 60 C with high capacity retention. It is assumed that the nanometer size materials (~50 nm) possessing a highly crystalline nature may generate improved performance at high rate current densities.

In this work we present results of measurements of structural (XRD), microstructural (SEM, EDX, TEM) and transport (electrical conductivity, Seebeck coefficient) properties as well as results of Mössbauer and FTIR spectroscopy studies of phospho-olivine materials with assumed chemical composition Li_1-3xAl_xFePO₄ (x = 0, 0.001, 0.005, 0.01, 0.02, 0.05 and 0.1). Based on the performed research, possibility of lithium sublattice doping by Al is discussed. Additionally, initial results of electrochemical tests of lithium batteries with obtained, phospho-olivine based cathode materials are provided.

LiFePO₄ has become of great interest as storage cathodes for rechargeable lithium batteries because of their high energy density, low raw materials cost, environmental friendliness, high thermal stability. In the present investigation, lithium iron phosphate (LiFePO₄) cathode material has been prepared by using hydrothermal synthesis. The structure of the sample has been studies by using X-ray diffraction. The XRD spectrum exhibited different characteristic peaks along with (311) predominant orientation corresponding to an orthorhombic crystal structure with Pnma space group. Electrical and dielectric properties were studied over a frequency range of 1 Hz – 1 MHz at different temperatures. The electrical conductivity was found to be increased with increasing temperature following Arrhenius relation with an estimated activation energy of 0.44 eV. The dielectric properties were analyzed in the framework of complex dielectric permittivity and complex electric modulus formalisms. The evolution of the complex permittivity as a function of frequency and temperature was investigated. Several important parameters such as activation energy, ionic hopping frequency, carrier concentration, ionic mobility and diffusion coefficient etc, were determined.