Synthesis of spindle-shaped nanoporous C–LiFePO4 composite and its application as a cathodes material in lithium ion batteries

• Published in: Electrochimica acta Vol. 56; no. 27; pp. 10204 - 10209
• Main Authors: Su, Chang, Xu, Lihuan, Wu, Botao, Zhang, Cheng
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 30.11.2011; Elsevier
• Subjects: Applied sciences; Cathodes; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrochemical properties; Exact sciences and technology; Feeding; Iron; LiFePO4; Lithium ion battery; Lithium-ion batteries; Microstructure; Nanostructure; Scanning electron microscopy; Synthesis; Lithium ion battery; Electrochemical properties; Microstructure; LiFePO4; LiFeP0; Nanoporous materials; Electrode material; Discharge charge cycle; Composite material; Surface structure; Electrical characteristic; Scanning electron microscopy; Cycling; Cathode; Iron Phosphates; Secondary cell; Carbon; X ray diffraction; Quaternary compound; Transmission electron microscopy; Hydrothermal synthesis; Morphology; Preparation; Lithion ion batteries; Lithium Phosphates; Electrochemical impedance spectroscopy
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2011.09.004

► The spindle-shaped LiFePO4 with hierarchical microporous structure self-assembled by nanoparticles has been synthesized by synthesis route B. ► The feeding sequences and iron sources seriously affected the microstructures and electrochemical properties of the resulting LiFePO4 cathodes. ► The cell performances of the synthesized LiFePO4 by synthesis route B were superior to that of LiFePO4 by synthesis route A. In this work, LiFePO4/C composites were prepared in hydrothermal system by using iron gluconate as iron source, and two feeding sequences during the preparation were comparatively studied. The morphology, crystal structure and charge–discharge performance of the prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and galvanostatic charge–discharge testing. The results showed that the feeding sequences and iron gluconate seriously affected the microstructures and electrochemical properties of the resulting LiFePO4 cathodes in lithium ion batteries. The spindle-shaped LiFePO4 with hierarchical microporous structure self-assembled by nanoparticles has been successfully synthesized by synthesis route B. In addition, the cell performance of the synthesized LiFePO4 by synthesis route B was better than that of LiFePO4 by synthesis route A. Specially at high rates, the superior rate performance of the spindle-shaped LiFePO4/C microstructure (LFP/C-B) was revealed. And special reversible capacities of ∼118 and ∼95mAhg−1 were obtained at rates of 2C and 5C, comparing to ∼96 and ∼68mAhg−1 for LFP/C-A.