A facile approach to enhance high-cutoff voltage cycle stability of LiNi0.5Co0.2Mn0.3O2 cathode materials using lithium titanium oxide

- LiNi0.5Co0.2Mn0.3O2 is coated with lithium titanium oxide via a facile process.
- Lithium titanium oxide possesses high electronic conductivity.
- Electrochemical performance of the LTO-coated NCM is significantly enhanced.

Ni-based layered LiNi0.5Co0.2Mn0.3O2 (NCM) compounds coated with lithium titanium oxide for lithium ion batteries were successfully achieved through a simple solid state synthesis process using TiO2 powder and CH3COOLi. Systematical measurements in structure, morphology and electrochemical properties have been applied. X-ray diffraction patterns showed the existence and conversion of lithium titanium oxide (Li4Ti5O12 and Li7Ti5O12 are labeled as LTO). A coating layer in the form of LTO could be observed and the thickness was approximately 10 nm with uniform distribution. Similarly, XPS was performed to confirm the existence of LTO. 1.0 wt.% LTO-coated NCM material exhibited higher capacity retentions of 91.0% than that of the bare one (64.3%) after 100 cycles at cutoff voltages of 4.5 V. Meanwhile, the LTO-coated NCM material showed significantly improved thermal stability compared with the pristine sample at an elevated 60 °C. In addition, it has proved that it is effective to enhance the electrochemical performances of electrodes by LTO modification.