The Effect of Ultracapacitor on the Performance of Series Range-Extended Hybrid Commercial Vehicle

Toward the goal of “dual carbon economy” development, new energy hybrid commercial vehicles have become the main vehicles to meet the future fuel consumption and emission targets. In order to meet the high requirements of commercial vehicles on power and to minimize the influence of ambient temperature on the power of the vehicle, this study proposes a composite energy storage system (CESS) incorporating ultracapacitors. To further understand the impact of ultracapacitor on the dynamic performance of the vehicle, this study compares the dynamics of series range-extended hybrid pickup trucks with and without ultracapacitor at ambient and low temperatures, as well as the effect of ultracapacitor on the service life of lithium-ion batteries, by means of simulation. The results show that at room temperature (25°C), the addition of ultracapacitor shortens the 0–100 km/h acceleration time of the whole vehicle by 24.4% and improves the off-road climbing performance by 11.7%; at low temperature (−20°C), the addition of ultracapacitor shortens the 0–100 km/h acceleration time of the whole vehicle by 88.8% and improves the off-road climbing performance by 67.9%. Under WLTC, 3% gradient conditions, the ultracapacitor increases the cycle life of the lithium-ion battery by about 9% and reduces heat generation by 11.7%.