Nanoscale gadolinium doped ceria (GDC) surface modification of Li-rich layered oxide as a high performance cathode material for lithium ion batteries

Nanoscale gadolinium doped ceria (GDC) has been successfully coated on Li-rich layered oxides Li1.2Mn0.54Ni0.13Co0.13O2 by a wet chemical deposition approach. Structure and morphology of the fabricated materials are characterized by XRD, SEM, TEM and XPS. The electrochemical testing results demonstrated that Li1.2Mn0.54Ni0.13Co0.13O2 with 3 wt% GDC coating shows outstanding electrochemical performance in regards of capacity retention and charge transfer resistance. The improved electrochemical performance can be ascribed to that the GDC coating layer can protect the Li1.2Mn0.54Ni0.13Co0.13O2 from being corroded by the organic electrolyte and provide sufficient active sites for electrons and Li+ ions diffusion and transportation. Moreover, the GDC coating layer can effectively suppress the oxygen loss from bulk Li1.2Mn0.54Ni0.13Co0.13O2 in the first charge process due to the oxygen vacancies in GDC, which resulting in an improved initial coulombic efficiency. The nanoscale GDC layer homogenously incorporated into LLMO surface can effectively keep the structure stability and mitigate the voltage fade during cycling.