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Battery Electric Vehicles (BEVs) and Hybrid Electric Vehicles (HEVs) are becoming relevant in the transportation sector, and it is therefore of utmost importance to find a solution to allow batteries to work safely and in a correct temperature range in which performance degradation and/or thermal runaway do not occur. For this purpose, a Battery Thermal Management System (BTMS) is required to ensure the correct operation of the battery pack. The design and control of an efficient BTMS is a complex task, in which multiple technical fields are involved. The paper mainly focuses on the thermal problems affecting the BTMS and sets two main goals: 1) to provide a comparison of two possible BTMS solutions, analyzing constraints and thermal performance for the design task; 2) to present a battery thermal 1D model able to describe the battery module behavior in real-time application to be implemented in a BMS control.

In the nowadays cities the personal mobility is one of the main goals to achieve in the automotive field, especially in consideration of the European emission and consumption standards set for 2020. Electrification of the existing car platform is not the answer and is not achievable in short period. Moreover problems like proportions of the vehicles and the cost of batteries and their weight to maintain the same range of performances makes necessary to define different vehicles, designed “around” their powertrains. Hybrid powertrains seem to be the right solution especially for small cars, like sub-A segment cars. In this paper a real case study is presented, the step by step designing phase, the system dimensioning and the selection of the different subsystems of XAM 2.0 city vehicle, an innovative prototype designed by a small group of people at the Politecnico di Torino.

This paper presents a Fuel Cell Electric Vehicle (FCEV) powertrain development and optimization, aiming to minimize hydrogen consumption. The vehicle is a prototype that run at the Shell Eco-marathon race and its powertrain is composed by a PEM fuel cell, supercapacitors and a DC electric motor. The supercapacitors serve as an energy buffer to satisfy the load peaks requested by the electric motor, allowing a smoother (and closer to a stationary application) working condition for the fuel cell. Thus, the fuel cell can achieve higher efficiency rates and the fuel consumption is minimized. Several models of the powertrain were developed using MATLAB-Simulink and then experimentally validated in laboratory and on the track. The proposed models allow to evaluate two main arrangements between fuel cell and supercapacitors: 1) through a DC/DC converter that sets the FC current to a desired value; 2) using a direct parallel connection between fuel cell and supercapacitors.

Nowadays gas emissions and fuel consumption are two of the major challenges for the automotive industry arisen from the ever-increasing relevance of environmental issues. Over the last few years, Hybrid Electric Vehicles (HEV) and Fuel Cell Vehicles have been developed as the most promising solutions that can address these challenges. XAM (eXtreme Automotive Mobility) is a parallel hybrid electric vehicle for urban transportation developed at the Politecnico of Turin. Since 2011 it participated to the Shell Eco-marathon Europe, a competition for low consumption vehicles. In the race XAM runs within the Urban Concept category and is powered by bio-ethanol. XAM is a plug-in parallel hybrid where traction can be provided by internal combustion engine or by electric motor fed by supercapacitor. A 1D simulation model of the vehicle and its subsystems has been created in AMESim in order to predict the behavior of the vehicle during the race.

This paper presents the design procedure of a vehicle battery pack, in terms of electrical and mechanical requirements with an innovative methodology to model Li-ion cells’ thermo-electro-mechanical behavior. A toroidal battery pack was developed for a widespread A-segment vehicle and designed to be placed in the spare wheel compartment. A novel FEM modelling approach is studied to predict if short circuits happen in case of vehicle crash, avoiding battery pack structure over-engineering. Thus, the classical approach in which cells were treated as a rigid and non-deformable block is overcome. At the beginning, the toroidal battery pack was sized considering a mild hybrid vehicle conversion. Then, the internal modules layout was defined including also electric connection and cooling system.

This paper presents the analysis of an innovative braking system as an alternative and environmentally friendly solution to traditional automotive friction brakes. The idea arose from the need to eliminate emissions from the braking system of an electric vehicle: traditional brakes, in fact, produce dust emissions due to the wear of the pads. The innovative solution, called Zero-Emissions Driving System (ZEDS), is a system composed of an electric motor (in-wheel motor) and an innovative brake. The latter has a geometry such that it houses MagnetoRheological Fluid (MRF) inside it, which can change its viscous properties according to the magnetic field passing through it. It is thus an electro-actuated brake, capable of generating a magnetic field passing through the fluid and developing braking torque. A performance analysis obtained by a simulation model built on Matlab Simulink is proposed.

Given the ever-increasing concern about environmental issues, the automotive industry is focusing on the development of innovative technologies that allow reduction of gas emissions and fuel consumption. Over the last few years, Hybrid Electric Vehicles (HEV) and Fuel Cell Vehicles have been developed as the most promising alternative solutions for many car manufacturers. Although fuel cells are considered as the best technology to have zero emission, the impact on infrastructure for a large-scale deployment is not yet solved. For this reason, HEV represent a valid shorter-term alternative that guarantees drastic emissions reduction and reduced fuel consumption with a much lower infrastructural impact. This paper reports the results obtained by the optimization of the emissions and fuel performances of a hybrid electric city vehicle for urban transportation named XAM (eXtreme Automotive Mobility). In order to optimize these performances, a 1D model of the vehicle has been created.