Journal of Applied Electrochemistry

, Volume 6, Issue 5, pp 431–444 | Cite as

Effects of charge rate and cycling on the morphology of Cd and Cd(OH)2 in sintered plate electrodes

  • R. Barnard
  • G. S. Edwards
  • J. A. Lee
  • F. L. Tye
Article
Received:

Abstract

Optical and scanning electron microscopy have been used to study the growth and redistribution of Cd and Cd(OH)2 in sintered plate electrodes as a function of charge rate and cycle number. As expected, the growth of both components was found to increase with increasing cycle number and decreasing charge rate. Because the deposits, particularly after extended cycling, always contained appreciable quantities of Cd metal in both the charged and discharged state, the sizes of Cd(OH)2 crystallites were difficult to quantify. High charge and discharge rates promoted greater aggregation and redistribution of active material towards the electrode edge. This resulted in a considerable decrease in the available pore volume per unit mass of active material and in extreme cases to localized pore blockage. The trapping of Cd metal by highly crystalline, unchargeable hexagonal platelets of (δ-Cd(OH)2 resulted in about 50% of the active material becoming obsolete after 100 cycles at high charge and discharge rates. At this stage only the finely divided Cd metal in the electrode interior continued to function. Low charge rates gave deposits of more uniform size and distribution but these contained a high percentage of large Cd particles which discharged less efficiently than those produced at the high charge rate.

Keywords

Discharge Rate Pore Volume Active Material Cycle Number High Charge 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Reference

  1. [1]
    R. Barnard, A. H. Rafinski, J. A. Lee and F. L. Tye ‘Power Sources 5’, Proc. 9th Int. Power Sources Symp, (Ed. D. H. Collins), Academic Press, London (1975) p. 183.Google Scholar
  2. [2]
    J. McCallum and A. H. Reed, Technical Report A. F. APL-TR-72-20, AD 743017, Battelle (1972).Google Scholar
  3. [3]
    R. D. Armstrong, K. Edmondson and J. A. LeeJ. Electroanal chem. 63 (1975) 287.Google Scholar
  4. [4]
    R. Barnard, K. Edmondson, J. A. Lee and F. L. TyeJ. Appl. Electrochem. To be published.Google Scholar
  5. [5]
    A. J. Salkind and G. W. Bodamer, ‘Batteries 2’ Proc. 4th Int. Power Sources Symp. (Ed. D. H. Collins), Pergamon Press (1964) p. 55Google Scholar
  6. [6]
    J. P. Harivel, B. Morignat and J. Migeon, ‘Batteries 2’ Proc. 4th Int. Power Sources Symp. (Ed. D. H. Collins), Pergamon Press (1964) p. 107.Google Scholar
  7. [7]
    E. Luksha, D. J. Gordy and C. J. MenardJ. Electrochem. Soc. 120 (1973) 1447.Google Scholar
  8. [8]
    M. W. Breiter and J. L. Weininger, ‘Power Sources’ Proc. 5th Int. Power Sources Symp. (Ed. D. H. Collins), Pergamon Press (1966) p. 269.Google Scholar
  9. [9]
    E. Lifshin and J. L. Weininger,Electrochem Tech 5 (1967) 5.Google Scholar
  10. [10]
    E. J. Casey and J. B. Vergette,Electrochim Acta. 14 (1969) 897.Google Scholar
  11. [11]
    P. Bro and H. Y. KangJ. Electrochem Soc. 117 (1971) 583.Google Scholar
  12. [12]
    J. S. Dunning, D. N. Bennion and J. NewmanJ. Electrochem Soc. 118 (1971) 1251.Google Scholar
  13. [13]
    Idem, ibid,120 (1973) 906.Google Scholar
  14. [14]
    P. SelangerJ. Appl. Electrochem. 4 (1974) 249, 259, 263.Google Scholar
  15. [15]
    R. D. Armstrong, A. D. Sperrin, F. L. Tye and G. D. West,ibid 2 (1972) 265.Google Scholar
  16. [16]
    Y. Okinaka,J. Electrochem Soc. 117 (1970) 583.Google Scholar
  17. [17]
    O. R. Pryakin. V. P. Galushko and E. F. Zavgorodnyaya.Electrokhimiya 9 (1973) 60.Google Scholar
  18. [18]
    V. P. Galushko, E. F. Zavgorodnyaya, N. V. Podol'skaya and Yu. P. Rodak,ibid 8 (1972) 1216.Google Scholar
  19. [19]
    F. G. Will and H.J. HessJ. Electrochem Soc. 1 (1973) 1.Google Scholar
  20. [20]
    Yu. I. Obed'kov and L. A. L'vovaElectrokhimiya 9 (1973) 1649.Google Scholar
  21. [21]
    Idem, ibid 10 (1974) 359.Google Scholar
  22. [22]
    K. Appelt,Electrochim Acta. 13 (1968) 1727.Google Scholar
  23. [23]
    R. D. Armstrong and G. D. West,J. Electroanal Chem. 30 (1971) 385.Google Scholar
  24. [24]
    Y. Okinaka and C. M. WhitehurstJ. Electrochem Soc. 117 (1970) 583.Google Scholar
  25. [25]
    R. Barnard, Unpublished work.Google Scholar
  26. [26]
    F. G. Will, ‘Power Sources 2’, Proc 6th Int Power Sources Symp. (Ed. D. H. Collins) Pergamon Press (1968) p. 149.Google Scholar
  27. [27]
    R. D. Armstrong and K. EdmondsonJ. Electroanal Chem. 53 (1974) 371.Google Scholar

Copyright information

© Chapman and Hall Ltd. 1976

Authors and Affiliations

  • R. Barnard
    • 1
  • G. S. Edwards
    • 1
  • J. A. Lee
    • 1
  • F. L. Tye
    • 1
  1. 1.Central LaboratoriesEver Ready Co. (Holdings) Ltd.London

Personalised recommendations