These plots point to a main basis for our proposed method: the trend curve can be approximated as a function of the shape 𝛕 = 𝜺 𝟏-𝜶 , for a given value of the parameter 𝜶 that seems to depend on the CBD internal porosity. Note that this equation is now used at the electrode level instead of at the internal CBD microstructure level. The continuous line shows the best fit for this function, with the values for 𝜶 presented on the plots in the bottom row. For completeness, the same data is presented in the supporting information section but considering the generalized form of this function, equation . It is noteworthy that all the values of 𝜶 here determined lie between 𝜶 = 𝟏. 𝟓 and 𝜶 = 𝟐. 𝟎, which are the expected results for an arrangement of spheres and cylinders, respectively . Furthermore, 𝜶 closely follows a linear trend, approaching 1.5