Quality of Low-Antimonic Lead Batteries

Research and experience have shown that cell voltage plays a significant role for the service lifetime of constantly charged high-antimonic lead batteries. It is generally believed that this also occures for newer types low-antimonic lead batteries. Since a battery charger keeps the total voltage at a constant level there will excist deviations between the individual cells. As a consequence of this the Swedish Union of Electricity Boards gives recommendations for tolerable cell voltage deviation within and after the warranty period. Some results of a long time (1976-1981) laboratory test of low-antimonic cells are reported. Late 1981 a series of measurements were performed on a great number of relative new batteries belonging to the Norwegian Telecommunication Administration. These measurements had to be performed with the batteries at normal working conditions. Consequently an automatic measuring technique with a statistical approach had to be used. During the last months of 1986 the measurements of the most interesting batteries were repeated, and capacity-tests on some of the cells were made. This paper presents the measuring method which had to be used due to the pulsating load of the batteries, and gives the results of the two series of measurements. The results are evaluated and some conclusions are drawn.