In this study, we first provided a brief overview of the existing approaches to deal with the anomalous solid-state diffusion impedance in LIBs, but there is still a lack of both an easily accessible and physically interpretable analysis method. We then introduced a novel analytical PDW model and coupled it with EECM analysis to tackle the troublesome anomalous solid-state diffusion impedance in LIBs. This novel approach has been successfully demonstrated to analyze both the thin-film LNMO electrodes and porous NCA electrodes. The analytical expression of PDW is derived from the classical Fickian diffusion framework, introducing non-unified diffusion coefficients originating from the diverse crystalline conditions of Li + diffusion paths, as demonstrated in the atomistic modeling results. In practice, PDW with two diffusion coefficients -grain boundary diffusion (fast) and bulk lattice diffusion (slow) -is sufficient for EECM analysis on LIBs. A good understanding of the theoretical assumptions and limitations of PDW model is essential xxiii for robust analysis. In future studies, a probability density function of the diffusion coefficient could be introduced to PDW to achieve a more accurate description of the parallel diffusion impedance. Determining the PDF of the diffusion coefficient will be challenging, but could be achieved through more extensive atomistic simulations. This topic will be explored in our future work.