A novel current dependent lithium ion capacitor model: Analysis and experimental driving cycle test validation

Nowadays, energy storage systems are playing an important role in several electrical applications. The modeling of these devices is very important, in particular, for electric vehicles, in order to understand and predict their behavior under different working conditions. Recently, the lithium-ion based solutions, and, in particular, lithium-ion capacitors (LiCs), are gaining a predominant position, as they display both high power and high energy densities. In the literature, different past works have modelled the LiCs using the electro-chemical impedance spectroscopy, a frequency domain technique. These models are able to represent the dynamic behavior of the LiC in a wide range of frequencies, currents and temperatures. On the other hand, they use a high number of parameters to be estimated, resulting quite complex to manage them. In the present paper, a novel current dependent LiC model, with only four unknown parameters characterized using a simple time domain technique, is presented.