In this work, we address the diffusion impedance on the basis of Fickian diffusion framework, in which the origin the anomalous diffusion behavior is associated with inhomogeneous diffusion paths. In literature , a lognormal distribution of the diffusion lengths is incorporated into the diffusion model to model the inhomogeneous diffusion paths and the anomalous diffusion impedance. However, as shown in Figure (a), the LNMO electrode, as thin as 80 nm, unlikely exhibits a log-normal distribution of the diffusion lengths, we hence propose a different perspective by incorporating different solid-state diffusion coefficients as main cause of the anomalous diffusion impedance instead of different diffusion lengths.