In recent years, in order to meet the demand for maintenance free batteries a sealed lead-acid battery has been taking the place of a flooded lead-acid battery and becoming widespread for use as a stationary type lead-acid battery for telecommunication.As a conventional means of determining the life of a flooded leadacid battery, measurement of specific gravity and visual check of the battery outside appearance have been performed. However, in a sealed lead-acid battery, this conventional method can not be used, and troublesome capacity testing and cell voltage monitoring have therefore been the only means to obtain information about battery deterioration.To determine the life of this sealed lead-acid battery, we paid attention to its internal impedance and limited our research to the life mode in a condition of floating charge that is usually used, and we have now developed a device capable of determining and displaying the battery life without disconnecting the load from the battery.

No abstract

No abstract