Achieving Highly Proton‐Resistant Zn–Pb Anode through Low Hydrogen Affinity and Strong Bonding for Long‐Life Electrolytic Zn//MnO2 Battery

High-energy electrolytic Zn//MnO₂ batteries show potential for grid-scale energy storage, but the severe hydrogen evolution corrosion (HEC) caused by acidic electrolytes results in subdued durability. Here, an all-around protection strategy is reported for achieving stable Zn metal anodes. First, a proton-resistant Pb-containing (Pb and Pb(OH)₂ ) interface is constructed on a Zn anode (denoted as Zn@Pb), which in situ forms PbSO₄ during H₂ SO₄ corrosion and protects the Zn substrate from HEC. Second, to improve the plating/stripping reversibility of Zn@Pb, Pb(CH₃ COO)₂ an additive (denoted as Zn@Pb-Ad) is introduced, which triggers PbSO₄ precipitation and releases trace Pb²⁺ that can dynamically deposit a Pb layer on the Zn plating layer to suppress HEC. The superior HEC resistance stems from the low affinity of PbSO₄ and Pb for H⁺ , as well as strong bonding between Pb-Zn or Pb-Pb, which increase the hydrogen evolution reaction overpotential and the H⁺ corrosion energy barrier. Consequently, the Zn@Pb-Ad//MnO₂ battery runs stably for 630 and 795 h in 0.2 and 0.1 m H₂ SO₄ electrolytes, respectively, which are >40 times better than that of bare Zn. The as-prepared A h-level battery achieves a one-month calendar life, opening the door to the next generation of high-durable grid-scale Zn batteries.