In the quest for greener and more efficient energy storage solutions, the exploration and utilization of renewable raw materials is essential. In this context, cellulose-derived separators play a central role in enhancing the performance of green energy storage devices. However, these often exhibit disadvantageous porosity and limited wet strength. Here, we demonstrate a facile approach to tailor thickness (ca. 40 μm), air permeability (0.1-200 cm