Mixed doped lithium nickel vanadate as cathode material by sol‐gel and polymer precursor method

摘要

The mixed doped LiNi1?xMnxVO4 (0?x?1) has been synthesised by using sol?gel and polymer precursor methods. X-ray diffraction, thermogravimetric analysis/differential thermogravimetric analysis and scanning electron microscopy analyses have been carried out to study the structural and physical properties of the samples which can be used as the cathode material for lithium ion batteries. Citric acid was added during the sample preparation as the chelating agent. The prepared samples have been characterised thermally by thermogravimetric analysis/differential thermogravimetric analysis. The analysis shows few endothermic peaks at 80, 301, 371 and 573°C and this is due to the weight loss during the thermal process which corresponds to the inorganic and organic decompositions of the precursor. Scanning electron microscopy images show that the grain size of the composite samples increases with increasing temperature for the sample fired from 500 to 800°C, revealing a spherical shape of grain distribution at low temperature and a polyhedral shape at the highest sintering temperature. The size of the particle synthesised using both methods is also discussed in this work.