Electrochemical impedance spectroscopy (EIS) is a widely used technique for the characterization of Lithium Ion Battery (LIB) porous electrodes, and to extract their tortuosity factors in particular, using transmission line models supported on homogenizations and oversimplifications of the actual electrode texture Here we use our a 4D (3D in space + time) physical model to simulate EIS carried out on NMC porous cathodes, derived from the simulation of their manufacturing process, in symmetric cells.[1]The calculations of EIS spectra on the manufacturing model-calculated porous electrodes (in a symmetric cell configuration) were done in a diluted electrolyte regime by explicit consideration of the spatial location of active material, carbon and binder domain (CBD) and pore phases, with distinctive physics for each of them.2 The calculated impedance responses are compared with our experimental results arising from NMC-based cathodes prepared in a similar way. The possibility to tune the physical properties of each phase in our 4D model allowed us to identify the different contributions to the EI spectra shapes. We found that for NMC-based cathodes there is a complex interplay between the solid and ionic conductivities, which affects the characteristic times at which each region of the porous electrode is accessed as a function of the frequency. Furthermore, we found that electrode inhomogeneities related to the spatial CBD location results in highly inhomogeneous impedance behaviors. We observe that these effects strongly depend on the electrode formulation and other manufacturing parameters, such as the electrode calendering. We believe that our 4D model constitutes a powerful tool to assess EI spectra beyond the limitations of traditional transmission line models. Shodiev, Abbos, Primo, Emiliano N., Chouchane, Mehdi, Lombardo, Teo, Ngandjong, Alain C., Rucci, Alexis & Franco, Alejandro A. 4D-resolved physical model for Electrochemical Impedance Spectroscopy of Li(Ni1-x-yMnxCoy)O2-based cathodes in symmetric cells: Consequences in tortuosity calculations. J. Power Sources (2020). 227871 doi:10.1016/j.jpowsour.2020.227871Chouchane, Mehdi, Rucci, Alexis, Lombardo, Teo, Ngandjong, Alain C. & Franco, Alejandro A. Lithium ion battery electrodes predicted from manufacturing simulations : Assessing the impact of the carbon-binder spatial location on the electrochemical performance. J. Power Sources (2019). 444, 227285 Figure 1