We here explore the possibilities of correlating experimental cell impedance with finite element methodology modelling for state-of-charge (SoC) indication in LiFePO-based half-cells. The impedance response has been modelled sequentially during battery cycling using Newman theory, and is compared with experimental data. It is found that the charge-transfer resistance is dependent of SoC during battery charging, which can be modelled in good agreement with experimental results. Moreover, it is seen that cell design parameters-e.g. calendering-dependent electrode porosity-influence the EIS response and can thus be estimated using the presented methodology.