Estimation of State-of-Charge of Lead-Acid Batteries Using Electrochemistry Theorem

Abstract

There are several methods to estimate the residual capacity of lead-acid batteries. Most of these methods are not able to precisely predict the amount of remaining capacity due to the battery aging effect. This paper presents a method using the electrochemistry theorem to analyze the electrode reaction resistance effect and to estimate the internal energy loss and the electrolyte specific gravity in batteries. Through a series of calculations, the state-of-charge of a lead-acid battery can be estimated. To validate the proposed algorithm, some experiments are conducted and the measured data is applied to the proposed method and two other methods for comparison. The experiment results prove that the proposed algorithm can accurately compute the state-of-charge of lead-acid batteries to a certain extend and can be used in real-time controls.