No abstract

In this work it is proposed an integrated measurement system able to measure simultaneously mechanical properties, dimensional variations and Young modulus, of a pouch lithium-ion battery under operative conditions. At the same time, the designed integrated system allows also the measurement of both electrochemical main quantities (current and potentials) and temperature distribution. The complex testing capabilities system was implemented in an owner-lab-made apparatus. Experimental data collected both under normal operational conditions, as well as on abused batteries, allow to establish safer operational limits and to determine proper operation conditions to prevent the battery malfunctioning.

This work aims at collecting data on the electrochemical behavior of high capacity cells of different chemistries in operative conditions. The final target is to define the most suitable battery for a given kind of usage, in our case neighborhood Electric Vehicle. Four different cells were tested: Li-ion type with Lithium Iron Phosphate cathode (LiFe), Li-ion type with Ni-Mn oxides (LiMn) and two different Li-ion Polymer (LiP) cells. The results obtained during field test show that the LiP cells exhibit lower dynamic polarization resistance with respect to both LiFe and LiMn ones and that the maximum power of LiP cells, in particular at low temperature conditions, is higher. The results suggest this method for a quick comparison (during field application) of different types of high capacity cells and for giving an index about the state of health of a cell

The diffusion of electric vehicles depends on a multiplicity of reasons, technical, economic, and at the end, there is also the driver's range anxiety, the fear don't reaching the recharging plug. An aid to overtaking this fear can be done by knowing the battery state of charge; the driver needs an electrochemical gauge indicating, in real time, the remaining fraction of vehicle range. The electrochemical behavior of large capacity Li-ion cell has been studied during the operation on an electric car, recording intensiodynamic polarization curves at different points of the run test. Some characteristic features in the curves of the cell tested, have been found and related to the run distance. The series of polarization curves related to a discharge cycle characterize the behavior of a cell, with respect to the power deliverable and the effective voltage plateau in the experimented dynamic regime. The plot of cell voltage interpolated at zero current (ZCV) vs. distance also characterizes a cell in order to accomplish a gauge of state of charge; the attempts have done better results than the open circuit voltage (OCV) method. The "electrochemical gauge" warns in real time how long range is remaining

Current limitations of battery systems for fully electric vehicles (FEV) are mainly related to performance, driving range, battery life, re-charging time and price per unit. New cell chemistries are able to mitigate these drawbacks, but are more prone to catastrophic failures due to a thermal runaway. Therefore, new and more advanced management strategies are necessary to safely prevent the energy storage system from ever coming into this critical situation. In this paper, a novel battery management system (BMS) architecture is introduced, which will be able to meet these high requirements by introducing a network that has smart satellite J. Langheim (&) Á S. Carcaillet Á P. Cavro