Effects of Cell and Module Configuration on Battery System in Electric Vehicles

Abstract

Battery pack is one of the most important powertrain components in Electric Vehicles (EV). The performance of battery pack directly affects vehicle’s range and performance. Configuration of cells and modules inside battery pack also plays an important role on battery performance and safety. In this study, the work deals with an electric vehicle that has 400 V DC bus voltage and 78 kWh total energy content. When the vehicle’s battery is designed, the criteria to be focused on are evaluated for three different configurations of given cell quantity. Thus, optimum design solution can be achieved. According to calculations, cost analysis, total electrical power loss and most efficient solution scenarios (alternatives) are determined for these three different configurations afterwards system complexity is optimized. In the first configuration, 8 series modules are selected which have 12s6p cell configuration. In the second configuration, there are 16 modules with 8s2p module combination. Each module is equipped with 12s3p cell configuration. Last configuration has 16 modules in series where each module has 6s6p cell configuration. Advantages and disadvantages of the systems are revealed as a result of the calculations made for each configuration.

Keywords

• Battery electric vehicle,battery pack,battery module,battery cell

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