# Electrification of a Class 8 Heavy-Duty Truck Considering Battery Pack Sizing and Cargo Capacity
###### Abstract  
The design and performance optimization of fully electric trucks constitute an integral goal of the transport sector to meet climate emergency measures and local air quality requirements. Most studies in the literature have determined the optimum pack size based on economic factors, without accounting for the details of pack behavior when varying the size. In this paper, the effect of battery pack sizing and cargo capacity of a class 8, 41-ton truck on its overall energy performance and technical parameters of its powertrain is investigated. For this purpose, the proposed electric truck is designed and mathematically modelled using AVL CRUISE M software. The second-order equivalent circuit model is developed to predict the battery packs' parameters. The proposed battery pack model is extracted from experimental analysis on SONY VTC6 lithium-ion batteries performed in the lab. The weight changes due to adding the battery packs to the truck are also estimated and have been taken into account. The mathematical model of the powertrain is simulated in the long-haul driving cycle considering different cargo capacities and battery pack sizes. The results of this study revealed that the battery pack voltage reached its minimum value when the maximum cargo capacity was applied for the 399 kWh battery pack. In addition, increasing the occupied cargo capacity from 10% to 100% resulted in an increase in the regenerative brake energy of up to 9.87 kWh, while changing the battery size imposed minimal impacts on regenerative brake energy recovery as well as energy consumption. b 202  
Various studies have analyzed the electrification of heavy-duty vehicles addressing aforementioned challenges. [PERSON] et al. [9] conducted an economic analysis between diesel, fuel cell, and battery electric long-haul trucks in the United States. Current battery electric trucks were seen to be nearly competitive to diesel trucks for trips below 500 km. For weight constrained cargo exceeding 500 km, fuel cells were nearly competitive to diesel. The more volume constrained the cargo, the greater the advantage to the battery electric truck, since the added mass of the battery pack does not limit cargo capacity. Energy and fuel price had a large effect on all of the comparisons, and such comparisons do not consider charging nor hydrogen refueling availability. [PERSON] et al. [16] also found that energy and fuel price influence electric truck feasibility in Latin America, with upfront costs being the largest barrier. Besides the cost of electricity, the cost of a battery pack influences the economic feasibility of EV heavy-duty vehicles. [PERSON] and [PERSON] [14] determined that the cost of battery pack depends on desired range and influences electric truck upfront costs. [PERSON] and [PERSON] [17] proposed using smaller battery packs for heavy-duty trucks and improving the fast charging network in order to reduce both the cost of battery electric trucks and their weight, improving their weight carrying capacity. Optimizing heavy-duty truck battery pack size would maximize the economic viability of such vehicles [18]. [PERSON] et al. [18] were able to find an ideal battery pack size by factoring in charging costs, battery costs, depreciation costs, and revenue. Large battery packs maximize range and payload size, but unnecessarily increase the weight and require a larger initial investment. On the contrary, a small battery pack limits the range and carrying capacity and relies more on the charging network. The previously mentioned studies rely on economic factors to determine the pack size, but details of pack behavior are not accounted for when varying the size. The subject of this research is to perform the optimal pack sizing considering the distance, power, weight, size of truck, and the volume of transported goods in order to maximize efficiency and energy usage of a heavy-duty truck.