An improved battery characterization method using a two-pulse load test

Abstract

It is very important to have the ability to determine the available capacity, the state of charge (SoC), and the state of health (SoH) of a battery; this ensures that the battery has the available power for the system requirements. A battery is aged by charging and discharging cycles; this process degrades the chemical composition of the battery. An undercharged battery has sulphation and stratification effects that shorten the lifetime of the battery. Overcharging causes gassing and water loss. This paper describes a novel two-pulse test to determine the AHC, SoC, and SoH of a valve regulated lead acid (VRLA) and a lithium ion battery. These parameters are related to the voltage drop after each pulse of current discharge. The first pulse stabilizes the battery relative to its previous history, and the second pulse establishes the parameters. The new approach is fully validated by experiment.