Effect of Various Organic Precursors on the Performance of LiFePO[sub 4]∕C Composite Cathode by Coprecipitation Method

The goal of this research was to study the effect of organic precursors with functionalized aromatic anhydrides or aromatic diketones on the performance of the composite. A coprecipitation method was applied to prepare a series of materials by calcinating amorphous with organic precursors at . The materials were characterized by X-ray diffraction, scanning electron microscopy, particle size analysis, thermal analysis, Brunauer-Emmett-Teller specific surface area and electrochemical methods. The obtained composites showed a well-ordered olivine-type structure with a minor impurity. The occurrence of the phase can be attributed to the relatively high temperature of . The composites produced by pyrolysis of an aromatic diketone with a longer alkoxy branch exhibited a better capacity compared to other types of organic compounds. The longer alkoxy aromatic diketone showed a better performance because its decomposition temperature was close to the temperature of the phase transformation resulting in a fine particle size and uniform carbon distribution on the composite surface. The performance of different organic precursors showed a strong relationship with its decomposition temperature, but was not in correlation with its weight loss. According to Raman spectral analysis, longer alkoxy aromatic diketones have a larger peak ratio indicating higher uniform and carbon content coating on particles.