VRLA battery aging characteristics

In the framework of an extended test program to better understand the behavior of valve-regulated lead-acid (VRLA) batteries under various operating conditions, FIAMM reports on a comparison of thermal runaway tests carried out on two different 48 V batteries. This testing involved both new and five-year field-aged cells taken from a telecommunications installation. The results give an indication of changes in susceptibility to thermal runaway as a VRLA battery ages. They also allow verification of the thermal management characteristics of the cell arrangement and housing. The results of accelerated aging tests according to Bellcore TR-NWT-001200 are also reported. The paper considers potential pitfalls in translating the theory behind accelerated tests into reality and discusses provisions to mitigate the side effects of high temperature testing. These test results, combined with those reported in previous papers, have given a clearer picture of the VRLA aging process and the implications of the changes taking place