The never ending pursuit of float voltage uniformity in stationary reserve battery plants

This paper traces the history of the concept of Pb-acid stationary telecommunication battery float voltage uniformity from the period when only lead antimony standby batteries were used, describes the problems encountered with the introduction of lead calcium cells and introduces the modern concepts which utilize positive and negative polarizations and Tafel curves to provide correct technical understanding of the causes and significance of voltage variability in antimony-free standby battery systems. The paper describes both early and recent attempts to control cell voltage variability by the use of individual cell electronic “controllers”. It presents comparative cell voltage, positive and negative polarizations on cells in actual telecommunication service, with or without the use of these controllers. The data demonstrate that voltage variability in Sb-free cells is primarily due to variations in negative polarizations and should have no effect on cell performance or life