Integrated VRLA-battery management system

The conventional flooded-type lead acid battery is being replaced by the sealed-type VRLA (valve-regulated lead-acid) battery, which is superior from the standpoints of economy, reliability, safety, ease of maintenance and construction. NTT started using sealed-type batteries in 1983. Sealed-type batteries now make up about 95% of the use in NTT (about 920000 at present). We developed the new battery-management system along with the battery-deterioration judgment unit, which automatically determines the level of deterioration of the batteries, and additionally, indicates the appropriate time to replace a defective battery. It makes for reliable maintenance-free batteries of power-supply units for telecommunication equipment and engine-generator starters or the like. However maintenance consolidation has made residing of maintenance workers difficult. Another problem is how to manage a battery for equipment such as an engine generator more efficiently. So we have developed the battery-management system with higher efficiency, which monitor a state of battery and then integrates its data from battery-management unit and battery-deterioration unit in a building at a remote office through public lines or wireless lines