Battery Sizing, Parametric Analysis, and Powertrain Design for a Class 8 Heavy-Duty Battery Electric Truck

Electrification of the transportation sector requires an energy-efficient electric powertrain supported by renewable sources of energy to limit the use of fossil fuels. However, the integration of battery electric powertrains in heavy-duty trucks seems more challenging than other types due to the high battery demand and negative impacts on the truck’s cargo capacity. In this paper, the battery sizing of a 41-tons Mercedes Actros truck is performed based on battery safety zone operating conditions. A parametric study is conducted to assess the impacts of sizing on a truck’s total cargo capacity as well as the body dynamic parameters. The numerical model of the Mercedes Actros electric powertrain is developed in AVL CRUISETM M software. The hybrid pulsed power characterization tests are performed on 3Ah lithium-ion NMC cells in the lab for fitting the second-order equivalent circuit model’s parameters used in the analysis. There are 6 battery packs with 456 to 684 kWh capacity each installed as an energy source for the powertrain based on the conditions of standard long-haul driving cycle. In parametric analysis, the battery capacity increased in the pre-mentioned range and its impacts on the final state of charge (SoC), pack voltage and road force on the truck’s cabin are assessed. The results of the parametric study have indicated that for putting the battery energy storage system in a safe operating zone (SoC would be between 80% and 30%), each battery pack capacity should be around 104.5 kWh resulting in a reduction of cargo capacity by 24.88% after electrification. The sharp road inclinations above 5% would result in non-negligible effects of the battery pack size variations on the truck chassis load.