Calcium Doping Effects on the Electrochemical Properties of LiFePO₄/C Cathode Materials for Lithium-Ion Batteries

Abstract:

This Olivine LiFe1-xCaxPO4/C composites (x=0 - 0.014) were synthesized by a solid-state method using sebasic acid as a carbon source. The structure and electrochemical properties of the LiFe1-xCaxPO4/C compounds were studied. The X-ray diffractometer (XRD) results indicated that Ca2+ doping did not affect the structure of the samples, but the unit cell volume of doped sample are slightly increased. Electrochemical measurements showed that the LiFe0.99Ca0.01PO4/C composite delivered a discharge capacity of 149 mAh g-1 at a 0.2 C-rate between 4.0 and 2.8 V, probably due to the significant improvement of electronic conductivity and Li+ ion diffusion. Besides, the cell can sustain a 20 C-rate, and this rate capability is equivalent to charge or discharge in 3 min.

• Periodical: Advanced Materials Research (Volumes 560-561)
• Pages: 499-505
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.560-561.499
• Online since: August 2012
• Authors: George Ting Kuo Fey, Cyun Jhe Yan, Yi Chuan Lin, Kai Pin Huang, Yung Da Cho, Pin Jiun Wu, Ya Sen Sun, Hsien Ming Kao
• Keywords: Calcium Doping, Carbon Composite, Lithium-Ion Battery

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