An In Situ Formed Surface Coating Layer Enabling LiCoO2 with Stable 4.6 V High‐Voltage Cycle Performances

• DOI: 10.1002/aenm.202001413
• Publication Date: 2020-06-15T08:04:18Z
• Authors: Yi Wang; Qinghua Zhang; Zhi‐Chen Xue; Lufeng Yang; Junyang Wang; Fanqi Meng; Qinghao Li; Hongyi Pan; Jie‐Nan Zhang; Zheng Jiang; Wanli Yang; Xiqian Yu; Lin Gu; Hong Li
• Keywords: Thermal Stability; High Voltage

Abstract The development of high‐voltage LiCoO 2 is essential for achieving lithium‐ion batteries with high volumetric energy density, however, it faces a great deal challenges owing to the materials, structure and interfacial instability issues. In this work, strategy developed, through heat annealing precoated surface layer in situ form high‐voltage‐stable coating layer, which demonstrated be highly effective improve performance . It discovered that reacts Li 1.5 Al 0.5 Ti (PO 4 ) 3 (LATP) at 700 °C exclusively spinel phases addition PO , are structurally coherent layered lattice thin LATP enables formation high‐quality layer. Spinel possess structures much weaker oxidizing ability oxygen than structure. addition, good conductor excellent chemical stability voltages. All these benefits contribute construction uniform conformal favorable lithium conducting kinetics surface. modified shows 4.6 V cycle both room temperature 45 °C. thermal greatly enhanced as well.