Development of on-line battery testing technology

The business activities of NTT Power and Building Facilities Inc. (NTT-F) consists of engineering and management for NTT's telecommunications system. A maintenance work related to batteries occupies about 1/4 of the entire telecommunications power system maintenance work. Moreover, a large number of valve regulated lead acid (VRLA) batteries have been installed and maintenance work of these batteries will increase in the future. To reduce this maintenance work, NTT-F has developed technology to evaluate the condition of a battery by discharging under a real load condition and to measure deterioration simply by measuring internal resistance of a single cell. NTT-F is scheduled to improve the efficiency of battery maintenance work by systematically using this technology.