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Modelling dynamic behaviours of the lithium‐ion (Li‐ion) battery and supercapacitor in electric vehicle applications is a key aspect for the emulation of the hybrid power supply. In this study, a dynamical model based on two non‐linear equivalent circuits is developed to describe the characteristics of the battery and supercapacitor during both steady‐state and transient conditions. The necessary parameters for the proposed model are extracted from measurement data in time and frequency domain using an optimisation algorithm. The developed model is coupled to power electronics devices fed by DC power supply to carry out a laboratory emulator of the hybrid power supply. This tool is mainly used for testing and verification of the electric vehicle performances with convenient and reproducible way. The proposed emulator avoids time‐consuming preconditioning and safety problems generally caused by the misuse of electrochemical components such as the Li‐ion battery. The modelling and experimental results show a good performance of the hybrid power supply emulator and confirm their feasibility over a wide range of operating points. [ABSTRACT FROM AUTHOR]

Currently, the vehicle manufacturers use the high power Li‐ion technology to supply the electric and hybrid vehicles. This technology is able to ensure the power needed to propel the vehicle. Until now several studies have been made by the laboratories and manufacturers to characterise this technology. The aim of these test (electric, thermal, aging,...) is to make comparison between Li‐ion technologies and choice the best one for each application. For that, they use accelerated cycling with different condition to characterise cells, what can reduce the tests duration. Unfortunately, this type of cycle cannot give us information about the aging of HP Li‐ion technology under real use of the vehicle. Firstly, the requirements specification (vehicle specification, battery technologies, mission) has been presented. After that, the authors will present the test bench developed in the laboratory to characterise batteries and study the aging of the HP technology. Here the authors present the study of the Li‐ion HP behaviour during almost 3 years and the modelling (electric, thermal and aging modelling) using a real driving cycle. The experimental results are compared with the results obtained with the developed ageing model. The obtained results prove the good performances of this technology in electric vehicle applications. [ABSTRACT FROM AUTHOR]