Preparation of Spherical FePO4 Cathode Material for Lithium Ion Batteries
The spherical FePO4 was prepared by a novel co-precipitation process followed by spray drying method, using Fe (NO3)3•9H2O, NH4H2PO4, NH3•H2O and polyvinyl alcohol. The pH value plays a pivotal role in determining the morphology of spherical particles; the sample, obtained at pH=3, was found to have the ideal spherical particles and electrochemical property. The X-ray diffraction analysis showed the phase transition of FePO4 with calcining temperature, amorphous FePO4 can exhibit better performance than the crystalline phase. Electrochemical behavior of spherical FePO4 was studied by the charge-discharge tests and electrochemical impedance spectroscopy. The results show that this process is a promising method to prepare spherical FePO4cathode materials for lithium ion batteries.
Weiguo Pan, Jianxing Ren and Yongguang Li
X. Yang et al., "Preparation of Spherical FePO4 Cathode Material for Lithium Ion Batteries", Advanced Materials Research, Vols. 347-353, pp. 576-581, 2012