EV technologies are still relatively new and under strong development. Many different designs and choices of technologies have been pursued by the automotive OEMs, battery industry and EV research centers. Although some standardized solutions are being promoted and becoming a new trend, there is an outstanding need for common platforms and sharing of knowledge and core technologies. This paper presents the development of a test platform, including three Li-ion batteries designed for EV applications and three associated bi-directional power converters, for testing impacts on different advanced loadings of EV batteries. The aim of the tests has been to study the impact of smart charging and fast charging on the power system, on the battery state of health and degradation, and to find out the limitations of the batteries for a Smart Grid. The paper outlines the advantages and disadvantages of both tests in terms of regulation of the aggregated local power, power capacity and the power exchange with the grid.Index Terms-Battery electric vehicle, battery management unit (BMU), distributed energy resources (DER), smart-grid, state of charge.

-Electric Vehicles (EV) technologies are still relatively new and under strong development. Although some standardized solutions are being promoted and becoming a new trend, there is an outstanding need for common platforms and sharing of knowledge and core technologies. This paper presents the development of a test platform, including three Li-ion batteries designed for EV applications, and three associated bi-directional power converters, for testing impacts on different advanced loadings of EV batteries. Different charging algorithms/profiles have been tested, including constant current and power, and forced and pulsed power. The aim of the tests has been to study the impact of smart charging and fast charging on the power system, on the battery state of health and degradation, and to find out the limitations of the batteries for a Smart Grid. The paper outlines the advantages and disadvantages of both tests in terms of regulation of the aggregated local power, power capacity and the power exchange with the grid. The smart charging tests performed have demonstrated that even with a simple control algorithm, without any forecasting, it is possible to provide the required charging and at the same time the power system services, reducing the peak power and the energy losses in the power connection line of the power exchange with the national grid.

This paper presents a battery test platform including two Li-ion battery designed for hybrid and EV applications, and charging/discharging tests under different operating conditions carried out for developing an accurate dynamic electro-thermal model of a high power Li-ion battery pack system. The aim of the tests has been to study the impact of the battery degradation and to find out the dynamic characteristics of the cells including nonlinear open circuit voltage, series resistance and parallel transient circuit at different charge/discharge currents and cell temperature. An equivalent circuit model, based on the runtime battery model and the Thevenin circuit model, with parameters obtained from the tests and depending on SOC, current and temperature has been implemented in MATLAB/Simulink and Power Factory. A good alignment between simulations and measurements has been found. Index Terms-BatteryManagement Unit (BMU); Distributed Energy Resources (DER); High Power Lithium-Cell Battery, State of Charge (SOC); Battery Electric Vehicle-BEV; I. NOMENCLATURE BEV-Battery Electric Vehicle; CAN-Controller Area Network; EV-Electrical Vehicle; HEV-Hybrid Electric Vehicle; SOC-State of Charge; II. INTRODUCTION dvanced energy storage devices and converters are introduced and tested in the last time for the next generation of EV for the smart grids [1], [2]. The different types of EV batteries have different characteristics regarding cost, energy density, safety, energy efficiency, degradation etc. making them suitable for different EV applications, such as hybrid EV (many small cycles), full EV (many full cycles), fast charging or V2G (cycles at high SOC) [3], [4].Today, batteries are still a critical component in the EV industrialization due to their high price, technical complexity, limited records of long term operational data, etc. One of the most commonly selected Li-ion battery types for commercial electric vehicles is Li-ion manganese oxide based due to its overall balanced performance in energy/power densities, lifetime, cost and safety. At the same time new Li-ion battery types started to show competitive key feature. Lithium-iron phosphate type was becoming a promising choice for PHEV's due to its high power/energy ratio favorable for HEV and PHEV as well as improved safety and cycle life. On the other hand, mixed oxide based Li-ion types such as NMC (Ni, Mn and Co based) showed high energy density, which is crucial for the driving range of pure EVs and started to be an interesting choice for EV's [3], [5]-[6]. Battery management system (BMS) functionalities are very important for the optimal use and handling of batteries. The functionalities of the BMS could play a critical role to make an EV battery robust and vulnerable towards charging tests [7]- [9]. A number of models have been developed in the last years to characterize and simulate lithium cells. Equivalent circuit modeling is the most common approach for battery numerical analysis [9]- [13]. In order to study various aspects of battery storage systems ac...

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