Influence of aging on SEI and charge transfer resistances and their dependence on current and temperature for a Li-ion NCA+NMC/graphite cell
Résumé
Modeling the electrical behavior of cells is often complex because several parameters have to be determined simultaneously, which may lead to inconsistencies and inaccuracies. In the present paper, we modeled the surface resistance by using a method based on rules of dependence, already presented in the literature, which makes it possible to separate the contributions of the SEI (Solid Electrolyte Interphase) layer and the charge transfer as a function of the temperature and the current. A physically consistent model is able to provide a better estimate of the surface resistance values at untested operating points. The main contributions of this work are to transpose this method to an NCA+NMC / graphite+SiO cell and to show that the proposed model is easier to recalibrate as the cell ages than interpolation tables. Besides, the proposed experimental protocol reduces the time needed for testing. By testing cells at different states of health, it was observed that the charge transfer resistance increased with both cycling and calendar aging and that the SEI resistance also increased in both cases because of the high temperatures to which the cells were subjected.
Domaines
Energie électriqueOrigine | Fichiers produits par l'(les) auteur(s) |
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