Directly Regenerating of Spent LiCoO2 with Gradient F‐Doped Subsurface towards Ultra‐Stable Storage Properties

even at 5.0 C, with retention rate (88.3 %) in 3.0-4.5 V. Supported by detailed electrochemical and kinetic analysis, the structural advantages are confirmed to boost the improved redox activity of Co-ions and the alleviating of irreversible oxygen-release. Give this, the work is anticipated to reveal the evolutions of regenerated LCO with the introduced F-elements, whilst providing the practical regeneration strategies toward excellent high-voltage properties.