This study introduces a proton-selective coating strategy to enhance the charge-storage kinetics and mass loading of high-mass-loading cathodes in zinc batteries (ZBs). The coating, a two-dimensional polyimine membrane (2DPM), is designed with dual ion-transport nanochannels that facilitate H+ conduction while blocking Zn2+. This approach enables a transition from Zn2+-dominated to H+-dominated Faradic reactions, significantly improving the performance of cathode materials such as NaV2O4·1.5H2O (NVO). The 2DPM coating enhances the specific capacity, areal capacity, and energy density of NVO, achieving a 56% increase in specific capacity and a state-of-the-art energy density of 33.8 Wh m-2. The coating also improves cycling stability, maintaining 87.8% of its original capacity after 1000 cycles compared to 68.6% for pristine NVO. Additionally, the 2DPM coating is shown to be universally effective for other cathode materials like ε-MnO2 and α-MoO3, demonstrating its potential for broader application in sustainable zinc batteries.This study introduces a proton-selective coating strategy to enhance the charge-storage kinetics and mass loading of high-mass-loading cathodes in zinc batteries (ZBs). The coating, a two-dimensional polyimine membrane (2DPM), is designed with dual ion-transport nanochannels that facilitate H+ conduction while blocking Zn2+. This approach enables a transition from Zn2+-dominated to H+-dominated Faradic reactions, significantly improving the performance of cathode materials such as NaV2O4·1.5H2O (NVO). The 2DPM coating enhances the specific capacity, areal capacity, and energy density of NVO, achieving a 56% increase in specific capacity and a state-of-the-art energy density of 33.8 Wh m-2. The coating also improves cycling stability, maintaining 87.8% of its original capacity after 1000 cycles compared to 68.6% for pristine NVO. Additionally, the 2DPM coating is shown to be universally effective for other cathode materials like ε-MnO2 and α-MoO3, demonstrating its potential for broader application in sustainable zinc batteries.