Influence of electrode design on the electrochemical performance of Li3V2(PO4)3/C nanocomposite cathode in lithium ion batteries

A new alkoxide-based sot containing lithium isopropoxide, vanadylisopropoxide, di-n-butyl-phosphate, acetic-acid and polyvinylpyrrolidone, was used for the synthesis of monoclinic alpha.-Li3V2(PO4)(3)/C composites by sot-gel and electrospinning techniques. The precursor mixture was highly soluble in organic solvents and thereby suitable for different synthesis techniques like sot-gel electrospinning or conventional sot-gel synthesis, to generate alpha-Li3V2(PO4)(3)/C nanocomposites with zero- and one-dimensionality. Electrospinning resulted in well-defined nanofibers and conventional sot-gel synthesis in polydisperse, isotropic nanoparticles. Phase composition and morphology in the composite nanostructures was examined by XRD, TGA, FT-IR, Raman, SEM and HR-TEM analysis. Comparative constant-current and cyclovoltammetric measurements of alpha-Li3V2(PO4)(3)/C composite applied as conventional film electrodes (nanoparticles and nanofibers) and self-supporting nanofiber electrodes revealed the influence of electrode texturing on the electrochemical performances. The nanofibrous self-supported electrodes showed superior cycling stability giving an initial discharge capacity of 124 mA h g(-1) at 0.2 degrees C with retention of 95% after 50 cycles with rate variation in a voltage range of 3-4.3 V. (C) 2012 Elsevier Ltd. All rights reserved.