Enhancing electrochemical performance of lithium-rich manganese-based cathode materials through lithium sulfate coating

The surface modification of Li1.2Mn0.54Ni0.13Co0.13O2 cathode material is carried out by heat treatment of the mixtures of Mn0.75Ni0.25C2O4 and (NH4)2SO4 absorbed on the surface of Li1.2Mn0.54Ni0.13Co0.13O2 material. The structural analysis by XRD, XPS, FTIR, and Raman spectroscopy demonstrates that Li2SO4 and metal oxides exist in the coating layer. The loading of coating layer and the calcination temperature play a crucial role in the initial Coulomb efficiency and cyclic stability of Li1.2Mn0.54Ni0.13Co0.13O2 cathode material. Compared with the pristine and metal oxide-coated sample, modified Li1.2Mn0.54Ni0.13Co0.13O2 with Li2SO4 coating exhibits higher first discharge specific capacity (233 mAh g−1 at 0.1 A g−1) and longer cyclic stability (retention of 94.7