Data‐Driven Cation Engineering Guides Electrolyte Design for Sustainable Aqueous Zinc Battery Chemistries

ABSTRACT Vanadium oxides have emerged as attractive cathode materials for zinc‐based batteries owing to their high theoretical capacity and versatile redox chemistry. Nevertheless, their persistent dissolution in aqueous electrolytes remains a long‐standing challenge, hindering real‐world implementation. Here, we develop a cation‐engineered electrolyte strategy enabled by a data‐driven framework that integrates density functional theory (DFT) calculations, discrete wavelet transform (DWT)‐based multi‐scale analysis, and differential feature extraction, to efficiently screen potential hetero‐cations and their combinations with objective statistic quantification, while minimizing trial‐and‐error experimentation and selection bias. As a proof of concept, the Zn/VO x batteries with the predicted Na + ‐Mg 2+ ‐Zn 2+ tri‐cation electrolyte (NMZ) achieved exceptional reversibility and record‐long cycling stability, sustaining 500 cycles at 0.2 A g −1 (1400 h) and 10,000 cycles at 5 A g −1 . The tri‐cation electrolyte successfully triggers a potential‐driven sequential ion insertion pathway involving Na + , Mg 2+ , and Zn 2+ , thereby fundamentally suppressing proton intercalation above 1.3 V and hydrated Zn 2+ insertion near 1.0 V (vs Zn 2+ /Zn). This work not only provides valuable data‐driven insights into ion‐engineering electrochemistry for regulating insertion stability but also uncovers critical ion‐related factors that are frequently overlooked. This approach establishes a reusable and statistically robust framework for guiding research across diverse battery chemistries.