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Electric vehicles are considered the most promising alternative to internal combustion engine vehicles towards a cleaner transportation sector. Having null tailpipe emissions, electric vehicles contribute to fight localized pollution, which is particularly important in overpopulated urban areas. However, the electric vehicle implies greenhouse gas emissions related to its production and to the electricity generation needed to charge its batteries. This study focuses the analysis on how the electric vehicle emissions vary when compared to internal combustion engine vehicles, depending on the electric power plant fleet and the efficiency during the use-phase. For this to be done, the GWP associated to the electricity generation on the electric vehicle most selling European countries are calculated. Similarly, electric vehicle’s use-phase energy efficiency is calculated under a wide range of driving conditions using the Monte Carlo method. The results from energy production and energy use-phases are compared to the GWP calculated for internal combustion engine vehicles for six different driving cycles, to obtain the threshold values for which electric vehicles provide GWP reduction. These threshold values are then matched with the current electricity power plant fleet and the electric vehicle promotion incentives of the European countries considered in the study, showing that some countries (e.g. France or Norway) are better-suited for electric vehicles adoption, while countries like Spain or Portugal should boost electric vehicle promotion policies. Furthermore, other countries in Europe, such as Germany or the UK that are doing an effort on decarbonizing their power plant fleet, do not offer immediate greenhouse gas emission reductions for the uptake of electric vehicles instead of conventional cars.Peer ReviewedPostprint (author's final draft

This paper describes a thermal model that represents the heat generation behavior of a large format (10.5 Ah) Li-ion pouch cell. The thermal model is based on the calculation of the heat generation from experimental measurements of internal resistance and the entropic heat coefficient. Predictions from the thermal model are compared with experimental adiabatic calorimetry data. Higher discharge rates and larger temperature operation ranges than the ones reported in prior studies are considered. Results from the thermal model simulations have a prediction error of 21% in comparison with the experimental ones for discharge processes carried out at moderate rates. For discharge processes carried out at high discharge rates a maximum prediction error of 15% has been determined. The advantages and disadvantages of the model are further discussed, taking into account aspects such as accuracy, model development and implementation in different thermal management system designs.The rechargeable battery industry will experience significant growth in the near future given the increased need for battery systems for power electronics, renewable energy storage and power systems for transportation applications. 1 These new applications require large format lithium-ion (Li-ion) cells (2-100 Ah) that need to be integrated in large scale modules and packs and be managed by ad hoc control electronics, the so-called battery management systems (BMS). 2 New large format Li-ion batteries are rapidly becoming available from commercial cell manufacturers. 3,4 However, these cells still have many problems that need to be overcome -problems such as operating temperature behavior and cell temperature non-uniformities, 5 among others -which could result in accelerated degradation of the battery power performance and the reduction of the operating life, 6 critically affecting the safety issues of battery packs.Therefore, the kinds of applications that are powered by largescale Li-ion batteries make it necessary to design thermal management systems (TMS) that improve battery performance. A precise determination of heat generation in batteries could improve the TMS design process. Several investigations deal with the thermal modeling of single-cell batteries 7-11 and battery packs. 12-14 Some of these models predict heat generation rates based on experimental data 5,12,15-19 or electrochemical models. 8,10,13,14,[20][21][22] Pals and Newman 10,14 developed a thermal model for a Li-ion cell based on the electrochemical model presented by Doyle et al. 23 Song and Evans 13 took a similar approach and presented a 2D thermal model for a cell stack where the heat generation was estimated from a 1D electrochemical model. Such models are well-suited for designing batteries, but they are not suitable for the computational resources of the electronics used in BMSs. 24 Experimental studies show that the overpotential and entropic heat coefficients gathered from experiments can be used to predict the volumetric heat generation rate. These thermal simulat...

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The European Project "Batteries 2020" unites nine partners jointly working on research and the development of competitive European automotive batteries. The project aims at increasing both the energy density and lifetime of large format pouch lithium-ion batteries towards the goals targeted for automotive batteries (250 Wh/kg at cell level, over 4000 cycles at 80% depth of discharge). Three parallel strategies are followed in order to achieve those targets: (i) Highly focused materials development; two improved generations of NMC cathode materials allows to improve the performance, stability and cyclability of state of the art battery cells. (ii) Better understanding of the ageing phenomena; a robust and realistic testing methodology has been developed and was carried out. Combined accelerated, real driving cycle tests, real field data, post-mortem analysis, modelling and validation with real driving profiles was used to obtain a thorough understanding of the degradation processes occurring in the battery cells. (iii) Reduction of battery cost; a way to reduce costs, increase battery residual value and improve sustainability is to consider second life uses of batteries used in electric vehicle application. These batteries are still operational and suitable to less restrictive conditions, such as those for stationary and renewable energy application. Therefore, possible second life opportunities have been identified and further assessed. In this paper, the main ageing effects of lithium ion batteries are explained. Next, an overview of different validated battery models will be discussed. Finally, a methodology for assessing the performance of the battery cells in a second life application is presented.