The application of PDW has been demonstrated on the study of thinfilm LNMO electrode with well-defined diffusion geometry and thickness. However, the preparation of thin-film electrodes requires sophisticated processes and tools, which are not accessible to most researchers. Therefore, we further demonstrate the use of the PDW model to study commonly used porous electrodes. The porous NCA electrodes were harvested from poweroptimized commercial batteries. As shown in Figure (a), approximately 10 to 15 µm of active porous layer was coated on the Al current collector due to the high-power design. Previous studies reveal that the porous structure significantly complicates impedance response, particularly the lowfrequency regions. The thin porous electrode design can minimize the porous diffusion and fulfill the boundary conditions predicted by the PDW model. Figure (b) shows the morphology of the NCA electrode consisted of spherelike secondary particles with radius around 2 to 5 µm. The secondary particles are agglomeration of much smaller primary particles, which is about 100 to 300 nm length. Estimating the diffusion length is more troublesome compared to thin-film electrodes. The radius of secondary particles is often used as the diffusion length to quantify diffusion coefficients in literature. However, a recent study shows that the diffusion length is independent of the secondary particle size for NMC cathode materials. The cracks formation and electrolyte penetration on the secondary NMC particles lead to shorter diffusion lengths, and irregular diffusion geometries. The traditional way to tackle this in FLW model is to fit a lumped parameter τ , where