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Vehicle electrification is one of the most important emerging trends in the transportation sector and a necessary step towards the reduction of polluting substances and greenhouse gas (GHG) emissions. However, electric vehicles still present some environmental criticalities, such as indirect emissions related to the electricity used for charging the traction battery, which depends on the considered national electricity generation mix. The leading approach for quantifying the potential environmental impacts is the Life Cycle Assessment (LCA), a standardized methodology that takes into account the whole life cycle of a product, including production, use phase, and end-of-life.

The second-life use of batteries from electric vehicles (EV) represents an excellent and cost-effective option for energy storage applications, including the control of fluctuations in energy supply and demand or in combination with solar photovoltaic and wind turbine. Indeed, these batteries are normally replaced from EV use before the end of their service life, when they still have 70-80% of the original capacity. Depending on the cell chemistry and the specific design, such batteries can still be employed in less stressful applications than the automotive one, including commercial, residential, and industrial applications. With the aim to promote the transition to a circular closed-loop economy for spent traction batteries, this study consists in a systematic literature review of available options for reusing EV batteries as a storage system in a factory environment, highlighting benefits and critical aspects.

In European Union (EU), transport causes about a quarter of the total greenhouse gases (GHG) emissions and road vehicles are the biggest contributors, with nearly three-quarters of the overall GHG emissions. In this context, many governments are adopting different strategies to achieve a sustainable mobility, including the electrification of public transport, such as full electric taxis (e-taxis). Indeed, battery electric vehicles (BEVs) represent a promising solution towards the achievement of sustainability since they involve zero emissions during the use phase, despite indirect emissions are generated during the charging of the traction battery according to the specific national electricity mix. However, a proper choice of the vehicle segment for the e-taxi and its battery capacity can represent a crucial factor in reducing the overall environmental impacts.

The Life Cycle Sustainability Assessment (LCA) methodology is today considered as a crucial paradigm with multiple levels of analysis, including the economic, social and environmental aspects. In this scenario, the purpose of the present research is to carry out an accurate and extensive LCA based analysis to compare the environmental impact, between conventional gasoline and hybrid vehicle powertrains. Two different powertrain scenarios were considered maintaining the same vehicle chassis. The performed analysis concerned resources and energy consumption as well as pollutant emission of each process, evaluating the impact of powertrain production, the vehicle use phase, and powertrain end of life scenarios. A large set of indicators - including human toxicity, eutrophication, and acidification - was considered. The study indicates that the potential of electrified vehicles basically depends on efficient production and recycling of the battery.

The interest in Unsteady Reynolds-Averaged Navier-Stokes (URANS)/Large Eddy Simulation (LES) hybrids, for the simulation of turbulent flows in Internal Combustion Engines (ICE), is consistently growing. An increasing number of applications can be found in the specialized literature for the past few years, including both seamless and zonal hybrid formulations. Following this trend, we have already developed a Detached Eddy Simulation (DES)-based zonal modeling technique, which was found to have adequate scale-resolving capabilities in several engine-like reference tests. In the present article we further extend our study by evaluating the effects of the underlying turbulence model and of the grid quality/morphology on the scale-resolved part of the flow. For that purpose, we consider DES formulations based on an enhanced version of the k-g URANS model and on the URANS form of the popular RNG k-ε model.

A two-equation Zonal-DES (ZDES) approach has been recently proposed by the authors as a suitable hybrid URANS/LES turbulence modeling alternative for Internal Combustion Engine flows. This approach is conceptually simple, as it is all based on a single URANS-like framework and the user is only required to explicitly mark which parts of the domain will be simulated in URANS, DES or LES mode. The ZDES rationale was initially developed for external aerodynamics applications, where the flow is statistically steady and the transition between zones of different types usually happens in the URANS-to-DES or URANS-to-LES direction. The same “one-way” transition process has been found to be fairly efficient also in steady-state internal flows with engine-like characteristics, such as abrupt expansions or intake ports with fixed valve position.