The last few decades have seen a significant increase in the number of electric vehicles (EVs) for private and public transportation around the world. This has resulted in high power demands on the electrical grid, especially when fast and ultra-fast or flash (at the bus-stop) charging are required. Consequently, a ground storage should be used in order to mitigate the peak power request period. This paper deals with an innovative and simple fast charging infrastructure based on supercapacitors, used to charge the energy storage system on board electric buses. According to the charging level of the electric bus, the proposed fast charging system is able to provide the maximum power of 180 kW without exceeding 30 s and without using DC–DC converters. In order to limit the maximum charging current, the electric bus is charged in three steps through three different connectors placed between the supercapacitors on board the bus and the fast charging system. The fast charging system has been carefully designed, taking into account several system parameters, such as charging time, maximum current, and voltage. Experimental tests have been performed on a fast charging station prototype to validate the theoretical analysis and functionality of the proposed architecture.

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Today’s city traffic is often congested, because of the large amount of vehicles in\ud comparison to the available space. Moreover road transportation contributes to the\ud urban pollution and greenhouse gas emissions. One solution in the urban\ud environment is the use of tramways. The most important bonus comes from the\ud inherent reversibility of electric drives: energy can be sent back to the electricity\ud source, while braking the vehicle. This can be done by installing some storage\ud device on-board trains, or installing them in one or more points of the supply\ud network.\ud This paper therefore draws some results about when these systems can be useful\ud and how they can be controlled. In general, storage systems with the following\ud variants can be considered:\ud  Stationary supercapacitors.\ud  Stationary high-power lithium batteries.\ud When the storage system is constituted by a supercapacitor, it is mandatory to\ud interpose between it and the line a DC/DC converter. When, on the contrary, it is\ud constituted by a lithium battery, the presence of the converter can be avoided.\ud This paper provides an evaluation of the variant based on stationary high power\ud lithium batteries, in a realistic case study. Some rather general conclusions will be\ud drawn from the proposed analysis

The aging behavior of lithium cell has a profound impact on its performance in terms of energy, power efficiency and capacity fade, especially when it is considered in End of Life (EOL) in automotive field. Lithium battery is considered in EOL if at 85-80% of nominal capacity. Today, the reusing of Electric and Hybrid Vehicles EOL batteries on less-demanding grid connected energy storage applications, giving them a second use/life, is an interesting solution to reduce high potential cost of lithium batteries. Currently, there is a lack of investigation of the performances of these second life batteries. In this paper, authors show the results of the impedance spectroscopy of 20 Ah lithium NMC batteries after EOL, exactly at 100, 85, 80, 60 and 50% of rated capacity, in a wide range of frequency: 450 mHz to 3.5 kHz. By results, there are many way to correlate battery state of health and battery impedance spectroscopy, especially when the battery is in second life.