Core-shell structure LiNi0.8Co0.1Mn0.1O2 cathode material with improved electrochemical performance at high voltage

Abstract

The design of Ni-rich core and Mn-rich shell is of great significance for improving the electrochemical performance of lithium-ion battery cathode materials at high voltage. The core-shell structure LiNi0.8Co0.1Mn0.1O2 (CS-NCM811) cathode materials is prepared through co-precipitation method. XRD shows that the cathode materials have α-NaFeO2 layered structure and SEM images show that the material has a good morphology. The elemental compositions in Ni, Co, and Mn of both the core and shell of the CS-NCM811 particles are analyzed by EDS. The electrochemical performance results show that the CS-NCM811 provides better cycling stability than the homogeneous. The capacity retention rate of CS-NCM811 at 3 C is significantly higher than that of homogeneous materials at 4.6 V. The change in morphology after 100 cycles proves that the core-shell structure can inhibit the side reaction and reduce polarization. In addition, the CS-NCM811 has better thermal stability with high exothermic temperature and low heat.