The electrochemical performance of aqueous zinc-ion batteries is strongly governed by the properties of their components and their interactions. In this study, a monoclinic NH4V4O10 cathode (space group C2/m) was synthesized, and the combined effects of slurry preparation, separator thickness, and electrolyte composition on its electrochemical performance were systematically investigated. The results reveal that pre-grinding the electrode materials before slurry preparation effectively mitigates capacity fading by promoting a more homogeneous electrode structure. Furthermore, increasing the separator thickness from 0.142 mm to 0.276 mm significantly enhances cycling stability by improving ion transport and suppressing undesirable side reactions. The influence of electrolyte chemistry was also examined, demonstrating that a 1 M Zn (OTf)2 electrolyte outperforms the conventional 1 M ZnSO4 electrolyte owing to its ability to inhibit the formation of parasitic by-products and dramatically reduce the charge-transfer resistance from 520 Ω to 1.23 Ω. Under the optimized conditions, the assembled cell delivered an initial discharge capacity of 167 mAh g-1 at 0.1 A g-1 and maintained stable cycling for 225 cycles. These findings highlight the critical influence of electrode processing, separator design, and electrolyte selection on improving the structural stability and reaction kinetics of NH4V4O10-based aqueous zinc-ion batteries, providing practical guidelines for developing high-performance zinc-ion energy storage systems.