Suppressing intergranular cracking with near-surface layer regulation for electrochemical-thermal stabilization of LiCoO 2

layered structure, suppressing intergranular cracking. An undistorted surface with reduced phase transitions was revealed by the HAADF-STEM. The interface regulation by post-cycle simulations and XRD stabilizes interplanar spacing. The strong B-O bonds lower the O 2p energies, preventing oxygen loss and side reactions confirmed by XPS and band structure. Therefore, even under 50 °C, the half-cell maintains a capacity retention rate of 79% after 200 cycles at 5C at 4.5 V.