• • Symmetric Zn//Zn cells sustain 4590 h of cycling at 0.5 mA cm−2/0.5 mAh cm−2, a 3–5× improvement over conventional aqueous electrolytes, directly reducing battery replacement frequency in stationary storage.
• • At a high current density of 1.0 mA cm−2 and capacity of 5.0 mAh cm−2, the depth of discharge reaches 85.4%, enabling >80% zinc utilization and lowering anode material cost per kWh.
• • Full cells pairing Zn with V2O5·1.6H2O retain >5000 cycles at 1.0 and 2.0 A g−1 with Coulombic efficiency near 100%, matching the cycle life required for 10-year grid ancillary service contracts.
• • The in situ formed organic/inorganic hybrid SEI suppresses the tip effect and free-water attack, reducing hydrogen evolution and byproduct accumulation that typically cause capacity fade within 500 cycles in baseline ZIBs.