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Research on Chemical Intermediates

, Volume 32, Issue 5, pp 389–402 | Cite as

Electrochemical characterization of negative electrodes consisting of surface-modified Zr0.9Ti0.1(Ni1.1Co0.1Mn0.5V0.2Cr0.1)x Laves-phase alloys

  • Masao Matsuoka
  • Tsuyoshi Matsuda
  • June Tamaki
  • Yoshifumi Yamamoto
  • Chiaki Iwakura
Article

Abstract

Laves-phase hydrogen storage alloy has a high potential for use as negative electrode material as alternative for the misch-metal-based material. In order to improve the energy density and the rate capability of negative electrode, chemical and mechanical modification of Lavesphase alloy with different stoichiometric ratios was carried out. Discharge capacity and high-rate dischargeabilty was evaluated by electrochemical methods and the characterization of Laves-phase alloy was made by X-ray diffraction, SEM observation and PCT measurement. The best result in discharge capacity could be obtained for stoichiometric Laves-phase alloy with a composition of Zr0.9Ti0.1Ni1.1Co0.1Mn0.5V0.2Cr0.1 by boiling in 10 M KOH solution. On the other hand, the high-rate dischargeability was increased remarkably by introducing mechanical grinding before alkali treatment. The cause for improved performance was discussed on the basis of thermodynamic stability of metal hydride and changes in crystal structure and surface morphology influencing on diffusion coefficient and diffusion path length of hydrogen.

Keywords

Laves phase electrode discharge capacity dischargeability 

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References

  1. 1.
    J. J. G. Willems, Philips J. Res. 39, 1 (1984).Google Scholar
  2. 2.
    K. A. Gschneidner Jr. and L. Eyring (Eds), in: Handbook on the Physics and Chemistry of Rare Earths, Vol. 21, p. 133. Elsevier, Amsterdam (1995).Google Scholar
  3. 3.
    Y. Moriwaki, T. Gamo, A. Shintani and T. Iwaki, Denki Kagaku 57, 488 (1989).Google Scholar
  4. 4.
    H. Nakano, S. Wakao, T. Shimizu and K. Morii, Denki Kagaku 66, 734 (1998).Google Scholar
  5. 5.
    C. Iwakura, Y. Kajiya, H. Yoneyama, T. Sakai, K. Oguro and H. Ishikawa, J. Electrochem. Soc. 136, 1351 (1989).CrossRefGoogle Scholar
  6. 6.
    K. Naito, T. Matsunami, K. Okuno, M. Matsuoka and C. Iwakura, J. Appl. Electrochem. 24, 808 (1994).CrossRefGoogle Scholar
  7. 7.
    M. Matsuoka, K. Asai, Y. Fukumoto and C. Iwakura, Electrochim. Acta 38, 659 (1993).CrossRefGoogle Scholar
  8. 8.
    M. Matsuoka, E. Nakayama, F. Uematsu, Y. Yamamoto and C. Iwakura, Electrochim. Acta 46, 2693 (2001).CrossRefGoogle Scholar
  9. 9.
    H. Ogawa, M. Ikoma, H. Kawano and I. Matsumoto, J. Power Sources 12, 393 (1989).Google Scholar
  10. 10.
    C. Iwakura, W. K. Choi, S. G. Zhang and H. Inoue, Electrochim. Acta 44, 1677 (1999).CrossRefGoogle Scholar
  11. 11.
    F. J. Liu, G. Sandrock and S. Suda, Z. Phys. Chem. 183, 163 (1994).Google Scholar
  12. 12.
    W. K. Choi, K. Yamataka, S. G. Zhang, H. Inoue and C. Iwakura, J. Electrochem. Soc. 146, 46 (1999).CrossRefGoogle Scholar

Copyright information

© VSP 2006

Authors and Affiliations

  • Masao Matsuoka
    • 1
  • Tsuyoshi Matsuda
    • 1
  • June Tamaki
    • 1
  • Yoshifumi Yamamoto
    • 1
  • Chiaki Iwakura
    • 2
  1. 1.Department of Applied ChemistryRitsumeikan UniversityShigaJapan
  2. 2.Department of Applied ChemistryOsaka Prefecture UniversitySakai, OsakaJapan

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