Some Problems of Assessing the State of Health of Lead-Acid Batteries During Operation

1. Background Telecommunications need reliable batteries as spare power supply. This explains the intensive search for informative and easy-to-perform testing methods for determining the battery and/or cell state of health. Stabonary computerized battery monitoring and testing systems are often economically not acceptable, especially for small telecommunication stations. Single classical testing methods (electrolyte density, open circuit and charge/discharge voltage, constant peak load, electrometry etc.) are often not able to ensure early-stage diagnostcs of battery's state-of-health. Modern testing methods like conductance measurements [1,2] however give not always satisfactory results because of the complicated electrochemical processes inside the battery. The problem for proper battery maintenance is to find inexpensive but reliable testing methods. In this study we try to check how relevant the results obtained by different state-of-health determining methods are to the actual capacity of lead-acid batteries used in telecommunication stations. The batteries under tests have been randomly selected among those used in the Bulgarian Telecommunication Company. All measurements were performed under real battery operating conditons and according to the existing measuring possibilities.