Characterization and Optimization of the Carbon Nanocoatings Onto LiFePO4 Particles for Lithium-Ion Batteries
The results of simple and environmental-friendly method of the carbon coatings on low-conductive cathode material powders have been developed, optimized and shown in this work. The carbon nanocoatings were prepared by wet impregnation process of precursor derived from hydrophilic polymer based on poly(N-vinylformamide) modified by pyromellitic acid  onto LiFePO4 particles.
The existence of nano-LiFePO4 was confirmed with X-ray powder diffraction (XRD). Transmission electron microscopy (TEM) was used to determine particle size and morphology of carbon nanocoated LFP material. The optimal calcination temperature of C/LFP composite precursors were investigated from thermal gravimetry analyses (TGA/DTG/STDA). The properties of carbon nanocoatings were determined by Raman spectroscopy and electrical conductivity measurements. The process of formation C/LiFePO4 nanocomposite significantly enhances the electrical conductivity of the material and improves its capacity retention and electrochemical performance.
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