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The Root Cause of the Rate Performance Improvement After Metal Doping: A Case Study of LiFePO4

  • Park, Chang-Kyoo (Department of Materials Science and Engineering, Korea University) ;
  • Park, Sung-Bin (Department of Materials Science and Engineering, Korea University) ;
  • Park, Ji-Hun (Department of Materials Science and Engineering, Korea University) ;
  • Shin, Ho-Chul (Energy Materials Lab, R&D center) ;
  • Cho, Won-Il (Advanced Battery Center, Korea Institute of Science and Technology) ;
  • Jang, Ho (Department of Materials Science and Engineering, Korea University)
  • Received : 2010.10.25
  • Accepted : 2011.01.11
  • Published : 2011.03.20

Abstract

This study investigates a root cause of the improved rate performance of $LiFePO_4$ after metal doping to Fesites. This is because the metal doped $LiFePO_4$/C maintains its initial capacity at higher C-rates than undoped one. Using $LiFePO_4$/C and doped $LiFe_{0.97}M_{0.03}PO_4$/C (M=$Al^{3+}$, $Cr^{3+}$, $Zr^{4+}$), which are synthesized by a mechanochemical process followed by one-step heat treatment, the Li content before and after chemical delithiation in the $LiFePO_4$/C and the binding energy are compared using atomic absorption spectroscopy (AAS) and X-ray photoelectron spectroscopy (XPS). The results from AAS and XPS indicate that the low Li content of the metal doped $LiFePO_4$/C after chemical delithiation is attributed to the low binding energy induced by weak Li-O interactions. The improved capacity retention of the doped $LiFePO_4$/C at high discharge rates is, therefore, achieved by relatively low binding energy between Li and O ions, which leads to fast Li diffusivity.

Keywords

References

  1. Padhi, A. K.; Nanjundaswamy, K. S.; Goodenough, J. B. J. Electrochem. Soc. 1997, 144, 1188-1194. https://doi.org/10.1149/1.1837571
  2. MacNeil, D. D.; Lu, Z.; Chen, Z.; Dahn, J. R. J. Power Sources2002, 108, 8-14. https://doi.org/10.1016/S0378-7753(01)01013-8
  3. Takahashi, M.; Tobishima, S. I.; Takei, K.; Sakurai, Y. Solid State Ionics 2002, 148, 283-289. https://doi.org/10.1016/S0167-2738(02)00064-4
  4. Padhi, A. K.; Nanjundaswamy, K. S.; Masquelier, C.; Okada, S.;Goodenough, J. B. J. Electrochem. Soc. 1997, 144, 1609-1613. https://doi.org/10.1149/1.1837649
  5. Takahashi, M.; Tobishima, S.; Takei, K.; Sakurai, Y. J. PowerSources 2001, 97/98, 508-511. https://doi.org/10.1016/S0378-7753(01)00728-5
  6. Barker, J.; Saidi, M. Y.; Swoyer, J. L. Electrochem. Solid-StateLett. 2003, 6, A53-A55. https://doi.org/10.1149/1.1544211
  7. Andersson, A. S.; Kalska, B.; Haggstrom, L.; Thomas, J. O. Solid State Ionics 2000, 130, 41-52. https://doi.org/10.1016/S0167-2738(00)00311-8
  8. Ravet, N.; Chouinard, Y.; Magnan, J. F.; Besner, S.; Gauthier, M.;Armand, M. J. Power Sources 2001, 97-98, 503-507. https://doi.org/10.1016/S0378-7753(01)00727-3
  9. Prosini, P. P.; Zane, D.; Pasquali, M. Electrochim. Acta 2001, 46,3517-3523. https://doi.org/10.1016/S0013-4686(01)00631-4
  10. Huang, H.; Yin, S. C.; Nazar, L. F. Electrochem, Solid State Lett.2001, 4, A170-A172. https://doi.org/10.1149/1.1396695
  11. Chen, Z.; Dahn, J. R. J. Electrochem. Soc. 2002, 149, A1184-A1189. https://doi.org/10.1149/1.1498255
  12. Chung, S. Y.; Bloking, J. T.; Chiang, Y. M. Nat. Mater. 2002, 1,123-128. https://doi.org/10.1038/nmat732
  13. Shi, S.; Liu, L.; Ouyang, C.; Wang, D. S.; Wang, Z.; Chen, L.;Huang, X. Phys. Rev. B 2003, 68, 195108, 1-5.
  14. Baker, J.; Saidi, M. Y.; Swoyer, J. L. Electrochem. Solid-state Lett.2003, 6, 53.
  15. Wang, G. X.; Needham, S.; Yao, J. J. Power Sources 2006, 159,282-286. https://doi.org/10.1016/j.jpowsour.2006.04.046
  16. Ait-Salah, A.; Dodd, J.; Mauger, A.; Yazami, R. Z. Anorg. Allg. Chem. 2006, 632, 1598-1605. https://doi.org/10.1002/zaac.200600090
  17. Shin, H. C.; Cho, W. I.; Jang, H. Electrochim. Acta 2006, 52,1472-1476. https://doi.org/10.1016/j.electacta.2006.01.078
  18. Shin, H. C.; Park, S. B.; Jang, H.; Chung, K. Y.; Cho, W. I.Electrochim. Acta 2008, 53, 7946-7951. https://doi.org/10.1016/j.electacta.2008.06.005
  19. Meethong, N.; Kao, Y. H.; Speakman, S. A.; Chiang, Y. M. Adv. Funct. Mater. 2009, 19, 1060-1070. https://doi.org/10.1002/adfm.200801617
  20. Liu, H.; Yang, H.; Li, J. Electrochim. Acta 2010, 55, 1626-1629. https://doi.org/10.1016/j.electacta.2009.10.039
  21. Lu, J.; Tang, Z.; Zhang, Z.; Shen, W. Materials Research Bulletin2005, 40, 2039-2046. https://doi.org/10.1016/j.materresbull.2005.07.022
  22. Wang, D.; Li, H.; Shi, S. Electrochim. Acta 2005, 50, 2955-2958. https://doi.org/10.1016/j.electacta.2004.11.045
  23. Moulder, J. F.; Stickle, W. F.; Sobol, P. E.; Bomben, K. D. Handbookof X-ray Phototelectron Spectroscopy; Physical Electronics Inc.: 1995.

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