Studies on Formation of Passivation Film on KMFC Anode with Initial Charge Temperature

탄소 부극에서 초기 충전온도별 부동태 피막 형성에 대한 연구

  • Park, Dong-Won (Department of Chemistry & RRC/HECS & IBS, Chonnam National University) ;
  • Kim, Woo-Seong (R&D Center, DaeJung Chemicals & Metals Co., LTD) ;
  • Choi, Yong-Kook (Department of Chemistry & RRC/HECS & IBS, Chonnam National University)
  • 박동원 (전남대학교 자연과학대학 화학과 & RRC/HECS & IBS) ;
  • 김우성 (대정화금(주) 중앙연구소) ;
  • 최용국 (전남대학교 자연과학대학 화학과 & RRC/HECS & IBS)
  • Received : 2005.01.21
  • Accepted : 2005.04.29
  • Published : 2005.08.10

Abstract

When carbon electrode is used as an anode in Li ion battery, passivation film forms on the electrode surface during the initial charge process due to so called Solid-Electrolyte Interphase (SEI). The passivation film formed by solvent decomposition during the initial charge process affects charge/discharge capacity. In this paper, 1 M $LiPF_6,EC:DEC$ (1 : 1, volume ratio) electrolyte with $Li_2CO_3$, at various temperatures, the electrochemical characteristics of passivation film formed on Kawasaki Mesophase Fine Carbon electrode surface were investigated by using chronopotentiometry, cyclic voltammetry, and impedance spectroscopy. Experimental observations indicated that as solvent decomposition occurred, the decomposition voltage was strongly dependent on ionic conductivity, which was low in the process at low temperature. The impedance of passivation film formed during the initial charge process, were dependent on the temperature.

리튬 이온 2차 전지의 부극으로 사용되는 탄소전극은 초기 충전시 전극 표면에 Solid Electrolyte Interphase (SEI)라고 불리는 부동태 피막을 형성한다. 초기 충전과정에서의 용매분해로 형성된 막은 충방전 용량에 큰 영향을 주는 것으로 조사되었다. 본 연구에서는 Kawasaki Mesophase Fine Carbon 부극과 1 M $LiPF_6,EC:DEC$ (1:1, 부피비)에 $Li_2CO_3$를 첨가하여 전극/전해질 계면에서 초기충전 온도에 따라 형성되는 부동태 피막의 전기화학적 특성을 시간대 전압법, 순환 전압-전류법, 임피던스법을 이용하여 조사하였다. 관찰된 결과에 따르면, 용매분해 반응이 일어날 때 리튬 이온의 전도도에 따라 용매분해 전위가 달라졌으며, 저온으로 갈수록 $Li^+$ 이온의 전도성이 떨어져 분해 전위 차이가 나타남을 알았다. 또한 여러 온도조건에서 초기 충전시 형성된 피막의 저항은 온도별로 달라짐을 확인하였다.

Keywords

Acknowledgement

Supported by : 전남대학교

References

  1. B. Scrosati, in: J. Lipkowski, P. N. Ross (Eds.), Electrochemistry of Novel Materials, VCR Publishers, New York, Chapter 3 (1993)
  2. Lithium Batteries, in: G. Pisotoia (Ed.), New Materials, Developments and Properties, Elsevier. Amsterdam (1994)
  3. K. Yamaguchi, J. Suzuki, M. Saito, K. Sekine, and T. Takamura, J. Power Sources, 97, 159 (2001) https://doi.org/10.1016/S0378-7753(01)00739-X
  4. C. Wang, A. J. Appleby, and F. E. Little, J. Electroanal. Chem., 519, 9 (2002) https://doi.org/10.1016/S0022-0728(01)00708-2
  5. J. R. Dahn, U. von Sacken, M. W. Juzkow, and H. AI-Janaby, J. Electrochem. Soc., 138, 2207 (1991) https://doi.org/10.1149/1.2085950
  6. E. Peled, C. Menachem, D. Bar-Tow, and A. Melman, J. Electrochem. Soc., 143, L4 (1996)
  7. K. Kanamura, S. Shiraishi, H. Tamura, and Z. J. Takehara, J. Electro. Chem. Soc., 141, 2379 (1994)
  8. K. Kanamura, H. Tamura, S. Shiraishi, and Z. I. Takehara, J. ElectroChem. Soc., 142, 340 (1995) https://doi.org/10.1149/1.2044000
  9. D. Aurbach, Y. Gofer, M. Ben-Zion, and P. Aped, J. Electroanal. Chem., 339, 451 (1993) https://doi.org/10.1016/0022-0728(92)80467-I
  10. D. Aurbach, A. Zaban, Y. Gofer, Y. Ein Ely, J. Weissman, O. Chusid, and O. Abramson, J. Power Sources, 54, 76 (1995) https://doi.org/10.1016/0378-7753(94)02044-4
  11. Z. X. Shu, R. S. McMillan, J. J. Murray, and J. J. Davidson, J. Electrochem. Soc., 143, 2230 (1996) https://doi.org/10.1149/1.1836985
  12. D. Aurbach, E. Zinigrad, Y Cohen, and H. Teller, Solid State lonics, 148, 406 (2002)
  13. A. V. Churikov, M. A. Volgin, and K. J. Pridatko, Electrochim. Acta., 47, 2857 (2002) https://doi.org/10.1016/S0013-4686(02)00183-4
  14. A. M. Andersson, M. Herstedt, A. G. Bishop, and K. Edstrm, Electrochim. Acta., 47, 1885 (2002) https://doi.org/10.1016/S0013-4686(02)00044-0
  15. K. Edstrm and M. Herranen, J. Electrochem. Soc., 147, 3628 (2000) https://doi.org/10.1149/1.1393950
  16. D. Aurbach and Y. Ein-Ely, J. Electrochem. Soc., 142, 1746 (1995) https://doi.org/10.1149/1.2044188
  17. J. R. Dahn, R. Fong, and U. von Sacken, J. Electrochem. Soc., 137, 2009 (1990) https://doi.org/10.1149/1.2086855
  18. J. O. Besenhard, M. Winter, J. Yang, and W. Biberacher, J. Power Sources, 54, 228 (1995) https://doi.org/10.1016/0378-7753(94)02073-C
  19. K.-J. Chung, B.-D. Choi, S.-K. Kim, W.-S. Kim, and Y.-K. Choi, J. Korean Elechem. Soc., 1, 28 (1998)
  20. M. C. Smart, B. V. Ratnakumar, S. Surampudi, Y Wang, X. Zhang, S. G. Greenbaum, A. Hightower, C. C. Ahn, and B. Fultz, J. Electrochem. Soc., 146, 3963 (1999) https://doi.org/10.1149/1.1392577
  21. Y-K. Choi, K.-I. Chung, W.-S. Kim, Y-E. Sung, and S.-M. Park, J. Power Sources, 104, 132 (2002) https://doi.org/10.1016/S0378-7753(01)00911-9
  22. N. Takami, A. Satoh, M. Hara, and T. Ohsaki, J. Electrochem. Soc., 142, 371 (1995) https://doi.org/10.1149/1.2044017