Fluorination from Surface to Bulk Stabilizing High Nickel Cathode Materials with Outstanding Electrochemical Performance

Abstract

Through interfacial fluorination and introducing F ions to bulk phase as anchors, the high-voltage high-rate cycling performance of high nickel cathodes is boosted. The fluorinated surface induces the formation of a thin, dense CEI layer to facilitate Li⁺ migration and hinder electrolyte erosion. Additionally, the substitution of F for O in bulk phase forms strong TM−F bonds, thereby enhancing surface and internal structural stability, and hindering the formation of microcracks and gas evolution.