A life indicator of stationary type sealed lead-acid battery

Abstract

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.

An adaptive battery monitoring system for an electric vehicle

“…One method that has been proposed [12] uses the battery intemal impedance, battery voltage and infortnation about the operating environment of the battery to make an estimate of the remaining life span of the battery. This method is however more suited to batteries used in standby applications rather than cyclic applications.…”

Estimation of the residual capacity of sealed lead-acid batteries by neural network

“…A visual inspection and an electrolyte gravity test are unfeasible, as is the case with conventional flooded or vented type batteries. Lately, new ways of predicting the remaining capacity and "health" of a battery have been established, based on inner impedance measurements [3] [4]. The phenomenon observed is that as the battery is discharged its inner impedance grows and eventually begins to fluctuate at some point, indicating either a need for replenishing or failure.…”