Electrical characterization and modelling of round spiral supercapacitors for high power applications

Our laboratory research project consists on the study of accelerating cycling and ageing of supercapacitors under railway and electrical traction constraints. Electrical model parameters according to physical and electrochemical phenomena represent an important key to investigate aging indicators of supercapacitors and give precious information on its state of health. These kinds of studies need a powerful techniques and instrumentations. Nowadays several electrical characterization methods exist. We have chosen to use two complementary methods: impedance spectroscopy and direct current charge/discharge methods. The present work describes the metrology defined to electrical characterization of supercapacitors. Electrical modelling based on simple tortuous pore impedance is explained. Some electrical parameters of the model defined for winded supercapacitors are investigated for different temperatures and different voltages. Finally, we have assessed the electrical model under full charge/discharge at high currents levels.