Prediction of Equivalent-Circuit Parameters for Double-Layer Capacitors Module

Although low energy density and low voltage tolerance limit the effectiveness of double-layer capacitors (DLCs) as a storage unit, many different lumped-parameter equivalent circuits have been recently proposed for the DLC. The purpose of this work is to predict equivalent-circuit parameters for DLC modules consisting of a single supercapacitor product of Maxwell BCAP3000-P270-T04 with a capacitance of 3000 F and NessCap ESHSR-1600C0-002R7A5T with a capacitance of 1600 F in series, in parallel, or the combination of the both. The equivalent circuit model for the single DLC consists of three RC branches, one of them with a voltage-dependent capacitance. The parameters for the DLC module are identified by charging it from zero to the rated voltage and by measuring its terminal voltage during the internal charge redistribution over the time of 30 min. The simulation and experiment results indicate the prediction of equivalent-circuit parameters concluded in this paper are feasible and effective.