Aqueous zinc-ion batteries (AZIBs) offer inherent safety, low cost, and high volumetric capacity, but face challenges such as dendrite formation and side reactions between zinc anodes and electrolytes. This study proposes a novel electrolyte additive, penta-sodium diethylene-triaminepentaacetic acid (DTPA-Na), with intermediate chelation strength to enhance electrochemical stability. DTPA-Na effectively modulates the anode/electrolyte interface, inhibits water-related side reactions, and suppresses dendrite growth by removing water molecules from the zinc metal-electrolyte interface and adjusting the solvation sheath of zinc ions. The additive also enhances the passivation of the zinc surface, reducing hydrogen evolution and corrosion. Zn||Zn symmetric cells with DTPA-Na additives can operate stably for over 3500 hours at 1 mA cm⁻². Zn||NH₄V₄O₁₀ full cells with DTPA-Na additives exhibit excellent cycling stability, retaining 84.6% of their capacity after 500 cycles at 1 A g⁻¹. The additive also improves the reversibility of Zn plating/stripping by modifying Zn²⁺ diffusion and deposition. The study demonstrates that DTPA-Na effectively suppresses dendrite formation and side reactions, leading to highly reversible Zn electrodes. The logical design of electrolytes based on chelation strength provides a practical approach for developing reliable aqueous zinc-ion batteries. The results highlight the potential of DTPA-Na as an effective additive for enhancing the performance and stability of AZIBs.Aqueous zinc-ion batteries (AZIBs) offer inherent safety, low cost, and high volumetric capacity, but face challenges such as dendrite formation and side reactions between zinc anodes and electrolytes. This study proposes a novel electrolyte additive, penta-sodium diethylene-triaminepentaacetic acid (DTPA-Na), with intermediate chelation strength to enhance electrochemical stability. DTPA-Na effectively modulates the anode/electrolyte interface, inhibits water-related side reactions, and suppresses dendrite growth by removing water molecules from the zinc metal-electrolyte interface and adjusting the solvation sheath of zinc ions. The additive also enhances the passivation of the zinc surface, reducing hydrogen evolution and corrosion. Zn||Zn symmetric cells with DTPA-Na additives can operate stably for over 3500 hours at 1 mA cm⁻². Zn||NH₄V₄O₁₀ full cells with DTPA-Na additives exhibit excellent cycling stability, retaining 84.6% of their capacity after 500 cycles at 1 A g⁻¹. The additive also improves the reversibility of Zn plating/stripping by modifying Zn²⁺ diffusion and deposition. The study demonstrates that DTPA-Na effectively suppresses dendrite formation and side reactions, leading to highly reversible Zn electrodes. The logical design of electrolytes based on chelation strength provides a practical approach for developing reliable aqueous zinc-ion batteries. The results highlight the potential of DTPA-Na as an effective additive for enhancing the performance and stability of AZIBs.