To explore advanced cathode materials for lithium ion batteries (LIBs), a nanoarchitectured LiNi1/3Co1/3Mn1/3O2 (LNCM) material is developed using a modified carbonate coprecipitation method in combination with a vacuum distillation‐crystallisation process. Compared with the LNCM materials produced by a traditional carbonate coprecipitation method, the prepared LNCM material synthesized through this modified method reveals a better hexagonal layered structure, smaller particle sizes (ca. 110.5 nm), and higher specific surface areas. Because of its unique structural characteristics, the as‐prepared LNCM material demonstrates excellent electrochemical properties including high rate capability and good cycleability when it is utilized as a cathode in the lithium ion battery (LIB).

Cobalt doped to modify the structure of lithium-rich cathode and obtain the material with superior electrochemical performance.

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A vanadium compound is applied as a coating material to improve the electrochemical performance of the lithium-rich layered oxide Li 1.2 Mn 0.6 Ni 0.2 O 2 . The physicochemical properties of the material before and after coating are characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), energy dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FT-IR). Results reveal that Li d V 2 O 5 (d is very small) is successfully coated on the as-prepared material, and the crystal properties of the powder have been modified after coating. The formation of the Li d V 2 O 5 coating layer is a result of some Li-ions diffusing from the Li 1.2 Mn 0.6 Ni 0.2 O 2 particle to the coating layer at the interface. The material before and after coating serve as the cathode for lithium-ion batteries and were investigated by galvanostatic measurements within a voltage range of 2.0-4.8 V (vs. Li/Li + ). The initial coulombic efficiency (CE1) of Li 1.2 Mn 0.6 Ni 0.2 O 2 is improved from 71.8% to 87.7% due to the Li d V 2 O 5 coating layer, which can act as an insertion host to accept the lithium ions that could not be inserted back into the bulk lattice during the first discharge process. Additionally, the electrochemical performances (cycling performance and rate capability) of the modified Li 1.2 Mn 0.6 Ni 0.2 O 2 are very superior to the pristine one. The significantly improved electrochemical performances are attributed primarily to: (i) the modified crystal properties after coating; (ii) the amelioration of the charge-transfer resistance after coating; (iii) the coating layer which can contribute to stabilizing the electrode surface by suppressing the side reactions between electrode and electrolyte.