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1d multi-domain modeling is a powerful tool for the fast prototyping of battery packs for electric vehicles. It can help identify the optimal layout for structural and thermal aspects and then support the battery sizing process. On the other hand, its simplicity may fail whereas precise simulations are needed. For example, a catastrophic event such as the thermal runaway can be triggered by a local peak of temperature on a single cell of the battery pack and then spread to the others. For this reason, the surface temperature distribution of a battery is crucial, and 1d models provide only an average value. Conversely, 3d models can provide this information even if at higher costs, in terms of time and computational efforts. 3d models of a Li-Po battery are not common in the literature because of the high complexity of the internal structure of a cell and the availability of experimental data for validation.

The LCA (Life Cycle Assessment) methodology is nowadays considered fundamental for the estimation and analysis of the economic and social impacts coming from the CO2 (Carbon Dioxide) footprint. It is a methodology for evaluating the “environmental footprint” of the product, “from cradle to grave” and it is carried out by quantifying the impacts deriving from both the use of resources and emissions into the environment. The aim of this study is to contribute to environmental assessment in the context of the sustainability of vehicular transport in urban areas. For this reason, through a comparative analysis of the LCA it is possible to evaluate the CO2 emissions deriving from cars during real use and relating to the entire life of the vehicles. Three comparisons were made considering pairs made up of an electric vehicle and an internal combustion vehicle of the same segment and category: small city cars, mid-size and SUV.

The use of electric propulsion systems for road vehicle applications is widely recognized as one of the most feasible solutions for sustainable mobility. On the other hand, improvement, and optimization of battery technologies remain challenging technical bottlenecks to be addressed. In particular, the design of proper packaging and heat dissipation structures can greatly support obtaining robust, high energy and power density battery packs. In this regard, this paper presents an experimental analysis of a metal foam-based frame used for the support and cooling of a small battery pack composed of 18650 cylindrical cells. The considered frame is manufactured in Al 6082 alloy according to the lost-PLA replication method. With a double extruder 3D printer it is possible to make polymer-based samples of the lost model. Through CAD modeling, different geometries can be replicated in order to get PLA samples.

The battery efficiency is strongly affected by the operating temperature, granting the best performance in a limited range. Great attention is given to the design and the testing of materials for the battery heat dissipation. In the present study, the thermal behavior of a Li-polymer cell, which is part of a battery pack for electric vehicles, is investigated. The cell is provided with different coatings of carbon, graphene, and silicone, used in turn, to dissipate the heat generated during the operation in natural convection. The coating is placed only on one side of the battery while the other one is inspected via thermal imaging. Optical diagnostics in the infrared band are used to evaluate the bi-dimensional distribution of the battery surface temperature and the effect of the coatings. Different operating conditions are tested by varying the current demand.

Hybrid electric vehicles are a suitable solution for the transition from fossil fuels-based transportation to electric mobility. They have the benefits of zero-emissions operation when only the electric engine is used preventing the typical range anxiety of full-electric vehicles. Also, they can have a low battery pack capacity and weight thanks to the continuous recharge from the internal combustion engine that becomes the only responsible for exhaust emissions. A practical solution to limit the combustion engine emissions is represented by the range extender configuration, where the engine works at a fixed operating point with the highest efficiency serving uniquely as a battery charger. In the face of the current world situation and future changes, research for alternative energy sources is crucial. Hydrogen can be used as an alternative fuel for common internal combustion engines; moreover, it has the great advantage of high efficiency (about 44%).

Focusing on coastal or inland navigation cities, where emissions from ships are not negligible concerning global ones, the possibility of reducing exhaust gas pollution would have more benefits for public health and air quality. Therefore, in recent years, increasing attention on environmental sustainability is driving the shipbuilding industry towards greener propulsion based on full-electric or hybrid-electric propulsion systems. This work is presented a parallel hybrid system composed of two electric motors, one internal combustion engine, and lithium battery storage. All motors are coupled to the propeller through a specially designed transmission system based on the High Sliding Gear theory (HSG). The hybrid-electric propulsion system is designed to extender the battery pack durability, ensuring a smooth profile of the required current, through the complementary action of the batteries and the internal combustion engine.