Expanders and additives to the paste

Organic expanders of ligno-sulphonates, BaSO4 and active carbon are added to the negative paste. It has been established that although BaSO4 is isomorphic with PbSO4 it has no effect on the phase composition of the paste. Ligno-sulphonates suppress fully the formation of 4PbO.PbSO4 and orthorhombic-PbO phases. Formation of 4BS is suppressed due to the suppressed formation of orthorhombic-PbO, which is a component of the 4BS phase. A family of eight lingo-sulphonates produced by Borregaard Ligno-Tech (Norway) has been investigated. The beneficial effect of the expander has been found to correlate positively with low average molecular weight of the lignins and of their derivates, high - COOH content, low OCH3 group and organic S content, optimum ArOH content and high lignin purity. Expanders with different chemical composition should be selected for different battery type applications. It has also been established that phenol groups of the expander structure react with Sb, Sn and Ca ions forming organometallic compounds, which influences battery performance.

References

  1. D. Pavlov, S. Gancheva, P. Andreev, Effect of hydrogen and oxygen on stability of expanders and performance of lead/acid batteries, J. Power Sources46 (1993) 349-359
  2. S. Gancheva, D. Pavlov, Influence of Expander Structure on the Performance of Lead-Acid Battery Negative Plate, Proceedings of the International Conference LABAT'93, 7-11 June 1993, Varna, Bulgaria p. 156
  3. B. Myrvold, D. Pavlov, Multivariate analysis for characterization of expanders, Proceedings of International conference LABAT’99, Sofia, 7-10 June, 1999, p.33
  4. B. Myrvold, D. Pavlov, T. Rogachev, M. Matrakova, G. Rodsrud, A new generation of highly efficient expander products and correlation between their chemical composition and the performance of the lead-acid battery, Proceedings of International conference LABAT’99, Sofia, 7-10 June, 1999, p.37
  5. D. Pavlov, B.O. Myrvold, T. Rogachev, M. Matrakova, A new generation of highly efficient expander products and correlation between their chemical composition and the performance of the lead-acid battery, J. Power Sources85 (2000) 79
  6. B.O. Myrvold, D. Pavlov, Multivariate analysis for characterization of expanders, J. Power Sources85 (2000) 92
  7.  T. J. McNally, M. Е. Sanford, B. О. Myrvold, D. Pavlov, T. Rogachev, G. Rapazov, M. Matrakova, Organic expander for lead-acid storage batteries, U.S.Patent Nо:  6346347 B1, Date of Patent: Feb. 12, 2002
  8. G. Papazov, D. Pavlov, B. Monahov, Influence of temperature on expander stability and on the cycle life of the negative plates, Proceedings of International Conference LABAT’02, Varna, 10-13 June 2002, p.105
  9. G. Papazov, D. Pavlov, and B. Monahov, Influence of temperature on expander stability and on the cycle life of negative plates, J. Power Sources113 (2003) 335
  10. M. Matrakova, T. Rogachev, D. Pavlov, B.O. Myrvold, Influence of phenolic group content in lignin expanders on the performance of negative lead-acid battery plates, Proceedings of International Conference LABAT’02, Varna, 10-13 June 2002, p.113
  11. M. Matrakova, T. Rogachev, D. Pavlov and B. O. Myrvold, Influence of phenolic group content in lignin expanders on the performance of negative lead–acid battery plates, J. Power Sources, 113 (2003) 345
  12. G. Petkova, P. Nikolov, D. Pavlov,Influence of polymer additives on the per-formance of lead-acid battery negative plate, Proceedings of the 6th Inter-national conference LABAT’2005, 13-16 June 2005, Varna, Bulgaria, p. 171
  13. G. Petkova, P. Nikolov, D. Pavlov, Influence of polymer additives on the performance of lead-acid battery negative plates, J. Power Sources158 (2006) 841

Keywords: negative paste additive, expanders, ligno-sulphonates, BaSO4, active carbon, cold cranking ability, lead-acid battery characteristics, new generation of efficient expanders, lignin’s molecular weight, COOH groups content of expander, OCH3 and organic S content of expander, phenol groups content of expander, expander stability