Uncontrollable zinc (Zn) plating and hydrogen evolution greatly undermine Zn anode reversibility. Previous electrolyte designs focus on suppressing H2O reactivity, however, the accumulation of alkaline byproducts during battery calendar aging and cycling still deteriorates the battery performance. Here, we present a direct strategy to tackle such problems using a strong Brønsted acid, bis(trifluoromethanesulfonyl)imide (HTFSI), as the electrolyte additive. This approach reformulates battery interfacial chemistry on both electrodes, suppresses continuous corrosion reactions and promotes uniform Zn deposition. The enrichment of hydrophobic TFSI– anions at the Zn|electrolyte interface creates an H2O-deficient micro-environment, thus inhibiting Zn corrosion reactions and inducing a ZnS-rich interphase. This highly acidic electrolyte demonstrates high Zn plating/stripping Coulombic efficiency up to 99.7% at 1 mA cm–2 ( > 99.8% under higher current density and areal capacity). Additionally, Zn | |ZnV6O9 full cells exhibit a high capacity retention of 76.8% after 2000 cycles.
水系锌金属电池因锌负极的独特优势受到广泛关注，但其在水系电解质中的自腐蚀反应生成OH−，导致不利的副反应和碱性沉淀物积累，严重影响电池性能。我们团队提出了一种解决方案：在电解质中添加疏水性强酸双(三氟甲基磺酰)亚胺（HTFSI）。研究表明，HTFSI能够有效防止碱性不溶性副产物在锌表面的沉积，促进锌的均匀沉积。此外，疏水性阴离子TFSI−在锌表面积累，减少锌与水的接触，并与H+协同作用，形成富含ZnS的界面保护层，有效抑制锌自腐蚀。这一方法显著提高了锌金属负极的稳定性和电池整体性能。
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