Optimal Sizing of Hybrid Battery-Supercapacitor Energy Storage System for Improved Vehicle Starting Performance

The lack of research on the optimal sizing of hybrid battery-supercapacitor energy storage systems (HBSCESSs) for improved vehicle starting performance has created a need to address the knowledge gap which is essential for advancing the field of energy storage for transportation. Therefore, improving vehicle starting performance is crucial for ensuring reliable and efficient transportation, and the use of hybrid energy storage systems (HESSs) that combine the advantages of batteries and supercapacitors has shown promise in achieving this goal. The optimal size of a HBSCESS for improved vehicle starting performance depends on the specific characteristics of the system, such as the power and energy requirements of the vehicle, the properties of the battery and supercapacitor, and the operating conditions. This study determines the optimal size of a HBSCESS for improved vehicle starting performance through a comprehensive analysis of the system's characteristics and performance, which requires high starting currents for vehicle starting. The results show that considering sensitivity and battery-to-supercapacitor ratio for supplying a starting current of 425 and 505 A from a 50–80 Ah battery capacity, the minimum optimised size is 312 and 404 Wh/kg for starting the vehicle. The battery needs to supply auxiliary loads such as lights, infotainment, air-conditioning system, etc.