Surface‐Anchored Nanoparticles Enable Electrode ζ‐Potential Control: Modulating Electrolyte Solvation to Form Inorganic‐Rich CEI for High‐Voltage Lithium‐Ion Batteries

Abstract The electrolyte, as the medium for charge transport, is critical to the stable cycling of lithium‐ion batteries. However, severe electrolyte decomposition hinders the widespread adoption of high‐voltage cathodes. Enhancing electrolyte stability and constructing a robust cathode‐electrolyte interface (CEI) are therefore essential. In this study, it demonstrates that anchoring metal oxide nanoparticles with positive ζ potentials (zeta potential) on the cathode surface effectively modulates the solvation environment of ions at the electrode‐electrolyte interface. This modulation alters ion distribution at the interface, promoting the formation of a stable, inorganic‐rich CEI. When applied to a conventional LiNi _0.5 Mn _1.5 O ₄ (LNMO) high‐voltage cathode, the surface‐anchored nanoparticles (SAN) strategy suppresses parasitic side reactions, prevents Mn ²⁺ dissolution, and improves cycling stability when paired with conventional carbonate electrolytes across wide electrochemical windows. This study presents a novel approach for designing the cathode‐electrolyte interface, advancing the practical application of high‐voltage lithium‐ion batteries.