0 avis
Direct determination of a single battery internal resistances distribution using a heterogeneous model
Archive ouverte : Communication dans un congrès
Edité par HAL CCSD
International audience. Lithium-ion batteries are getting larger due to the expansion of transportation and mass storage markets and they can now contain up to thousands of cells. However, a sole damaged cell can significantly impact the whole battery pack efficiency. Thus, the diagnosis of a single cell remains critical for those systems. Many methods exist in which the cell is considered homogeneous. We recently developed a heterogeneous equivalent circuit model that considers a distribution of internal resistances to better represent a real single cell behavior. This resistances distribution (RD) may bring valuable information about a single cell internal quality, but only if it is determined with a sufficient accuracy. In this paper, we propose an algorithm that allows a responsive determination of the RD. The results are compared to other determination methods. This resistances distribution (RD), which is determined thanks to the preliminary construction of a homogenous model and a single discharge, is also valid for other operating conditions. This proves the relevance of the determination method and it should now be usable to detect abnormal evolution of the RD during a single cell lifetime. Although this work is developed for a single cell, it can also be used for several cells connected in parallel and may thus be used to detect a damaged cell inside a battery pack.