Online state‐of‐charge estimation by modified Coulomb counting method based on the estimated parameters of lithium‐ion battery

Summary The state‐of‐charge (SOC) of the battery is most critical parameter for an electric vehicle (EV) dashboard. Generally, Coulomb counting (CC) method used SOC estimation, but conventional CC has some errors due to initial determination. This work uses modeling and estimation a lithium‐iron‐phosphate (LFP) determine SOC. equivalent circuit models (ECMs) have been parameters by least‐squares (LSE) algorithm. algorithm only experimental terminal voltage current data from Arbin testing system. ECM vary with SOC, differential capacity plot explained variation. can be estimated using relationship between open‐circuit (OCV). Additionally, modified proposed solve problem estimating determining OCV‐SOC relation data. validated comparing ECMs physical profiles.