Analysis and interpretation of conductance measurements used to assess the state-of-health of valve regulated lead acid batteries

This paper presents data showing conductance aging of new valve-regulated Pb-acid (VRLA) secondary cells and capacity/conductance aging of older cells. It presents data showing the comparative accuracy of several techniques for selection of a cell conductance value suitable for use in field determination of cell pass/fail conditions based on either capacity failures below 80% or below 50% of rated value. The accuracy of the various selected conductance values are determined by actual comparison to cell by cell capacity/conductance data. This data represents 192 cells of 1000 Ah (ampere hour) size in 48 volt telecom use and 96 cells of 600 Ah size in 24 volt strings in another type of telecom usage. The data presented should allow the user to select a technique which appears most suitable to his needs and capabilities