The relationship between the coating comma gap, electrode thickness, mass loading, and porosity are now assessed for the 8%Si/83%Gr slurry blend. Details on the coating parameters are presented in Methods. Table shows the resulting electrode properties when coating using 0.3 m/min line speed. When coating the 8%Si/83%Gr slurry blend, the comma gap and the resulting electrode's mass loading vary linearly. The porosity is nearly independent of the mass loading and the used casting gap. Surface and cross-sectional SEM images show the morphology of the electrodes when using a comma gap of 100 and 300 µm. The surface SEM images show that the big graphite grains are well distributed over the electrode and surrounded by lighter grey particles (see Figure and, respectively). The cross-sectional images evidence the contact of the electrode with the current collector. For the comma gap of 100 µm, the electrode has solid contact with the copper collector, contrary to the electrode coated a 300 µm, where there is a cavity between the current collector and the casted electrode (see Figure and d, respectively), causing cracking over the electrode (see Figure ). This lack of contact between the electrode and the current collector could be due to a poorer slurry contact with the copper foil, thus higher surface tension. The surface energy can be enhanced by oxidizing or texturizing the copper to improve the interaction between the slurry and the correct collector. In this case, the oxide groups in the current collector could bind more effectively with the CMC binder, and the rough-surface Cu foil could have a higher surface area and tighter contact between Si and Gr. Otherwise, the slurry's surface tension can be reduced by adding a cosolvent such as isopropanol. An alternative explanation for the cracks formed in this thick electrode could be the mixing sequence that may affect the casted properties of the electrode. In our slurry methodology, we mixed the active materials and conductive additive with the CMC binder, which may have facilitated a gel-like formation (see Figure , G' > G'' at 10 Hz). This gel-like may render a higher surface tension slurry that could not be suitable for thicker electrode preparation. In contrast, it does not affect when coating thinner electrodes down to 54 ± 1 µm.