An innovative and economical method to determine the state of health of the single components of batteries, allowing to study their aging dynamic and decide when to discard them, was patented by three researchers at the ENEA Systems and Technologies for Sustainable Mobility Laboratory, who validated the new method both through simulation and real testing.
“The battery packs installed in electric vehicles or for stationary applications are made by connecting several groups of elementary cells. It is possible to demonstrate that in a battery pack the most degraded cell affects the behavior of the entire pack, and that with age progression the difference in performance of individual cells increases. The method we have developed enables us to identify the single degraded cell or the group it belongs to, thus deciding to replace the element or the entire pack “, explained Manlio Pasquali, ENEA researcher and inventor of the patent together with Natascia Andrenacci and Francesco Vellucci.
The patented system considers the performance of a standard cell on a reference cycle chosen by the user, defined on the basis of the information provided by the manufacturer, and that of a degraded cell to be discarded, defined on the basis of the characteristics of the specific application, and relates them to the performance of each single group of cells that make up the battery pack. The numerical data obtained from the system allow to analyze the dynamics of aging and / or estimate the residual time or life cycles.
Currently, international research is focused on finding diagnostic systems or methods both to identify possible technical problems (malfunction of a cell, bad welds or disconnected units) and to predict the residual life of the entire pack.
“In general, the methods proposed in the literature employ tests which take a long time to excute and require the use of sophisticated and expensive measuring tools. One of the advantages of this system is that it does not require any dedicated instrumentation but it employs the standard one available in the battery pack and that testing requires a standard operation performed periodically on the pack “, Pasquali concluded.
For more information please contact:
Manlio Pasquali, ENEA – Systems and Technologies for Sustainable Mobility Laboratory, [email protected]
Source: ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development