One-Spot Facile Synthesis of Single-Crystal LiNi_0.5Co_0.2Mn_0.3O₂ Cathode Materials for Li-ion Batteries

Abstract

The layered lithium-metal oxides are promising cathode materials for Li-ion batteries. Nevertheless, their widespread applications have been limited by the high cost, complex process, and poor stability resulting from the Ni²⁺/Li⁺ mixing. Hence, we have developed a facile one-spot method combining glucose and urea to form a deep eutectic solvent, which could lead to the homogeneous distribution and uniform mixing of transition-metal ions at the atomic level. LiNi_0.5Co_0.2Mn_0.3O₂ (NCM523) polyhedron with high homogeneity could be obtained through in situ chelating Ni²⁺, Co³⁺, and Mn⁴⁺ by the amid groups. The prepared material exhibits a relatively high initial electrochemical property, which is due to the unique single-crystal hierarchical porous nano/microstructure, the polyhedron with exposed active surfaces, and the negligible Ni²⁺/Li⁺ mixing level. This one-spot approach could be expanded to manufacture other hybrid transition-metal-based cathode materials for batteries.