کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1285991 | 973169 | 2007 | 6 صفحه PDF | دانلود رایگان |

The effects of fluorine substitution on the electrochemical properties of LiFePO4/C cathode materials were studied. Samples with stoichiometric proportion of LiFe(PO4)1−xF3x/C (x = 0.025, 0.05, 0.1) were prepared by adding LiF in the starting materials of LiFePO4/C. XRD and XPS analyses indicate that LiF was completely introduced into bulk LiFePO4 structure in LiFe(PO4)1−xF3x/C (x = 0.025, 0.05) samples, while there was still some excess of LiF in LiFe(PO4)0.9F0.3/C sample. The results of electrochemical measurement show that F-substitution can improve the rate capability of these cathode materials. The LiFe(PO4)0.9F0.3/C sample showed the best high rate performance. Its discharge capacity at 10 C rate was 110 mAh g−1 with a discharge voltage plateau of 3.31–3.0 V versus Li/Li+. The LiFe(PO4)0.9F0.3/C sample also showed obviously better cycling life at high temperature than the other samples.
Journal: Journal of Power Sources - Volume 174, Issue 2, 6 December 2007, Pages 720–725