Copyright @ 2009 Journal of New Materials for Electrochemical Systems All rights reserved.

Open Full Contents

Preparation and Characterization of Spherical Li₃V₂(PO₄)₃/C Cathode Material for Lithium-ion Batteries

Pages: 201-205

G. Yang^1,*, J. R. Ying^1,2,*, J. Gao¹, C. Y. Jiang¹, and C. R. Wan¹

¹Institute of Nuclear and New Energy Technology, Tsinghua University, P.O. Box 1021, Beijing 102201, P. R. China
²Institute of Chemical Engineering, Ningbo University of Technology, 89 Cuibai Road, Ningbo 315016, Zhejiang Province, P. R. China

Received: November 3, 2008, Accepted: August 29, 2009

Abstract:
Monoclinic lithium vanadium phosphate Li3V2(PO4)3 is a very promising polyanion-type cathode material for lithium-ion batteries. In this work, we synthesized spherical Li3V2(PO4)3 powder via melting V2O5 and quenching followed by spray drying and carbothermal reduction processes, using NH4VO3, LiOH·H2O, H3PO4 and C12H22O11 as the raw materials. The structure and morphology of the Li3V2(PO4)3 powders were characterized. The electrochemical property of the spherical Li3V2(PO4)3 cathode material was characterized by electrochemical measurements. At cut-off voltages of 3.0–4.3 V, 3.0–4.8 V and 1.5–4.8V with current density of 0.2 mA·cm-2, the cathode material showed initial discharge capacity of 124.7 mAh·g-1, 157.3 mAh·g-1, 270.2 mAh·g-1 and capacity retention of 98.4%, 83.1% and 84.0% after 50 cycles, respectively. The charge-discharge performance tested at different current densities of 0.04 mA·cm-2, 0.08 mA·cm-2, 0.2 mA·cm-2, 0.4 mA·cm-2, 0.8 mA·cm-2 and 2 mA·cm-2 also showed the good rate capability.

Keywords:
Lithium secondary batteries; Li3V2(PO4)3; Spray-dried; Spherical.