A novel LiCoPO4-coated core–shell structure for spinel LiNi0.5Mn1.5O4 as a high-performance cathode material for lithium-ion batteries

Abstract

The electrochemical performance of spinel LiNi_0.5Mn_1.5O₄ is strongly influenced by the content of Mn³⁺. In this work, a novel olivine LiCoPO₄ shell coated structure was designed to tune the content of Mn³⁺ in LiNi_0.5Mn_1.5O₄. The results indicated that after modification, LiNi_0.5Mn_1.5O₄@LiCoPO₄ can greatly improve the electrochemical performance by inducing an appropriate amount of Mn³⁺. A sample containing 5 wt% LiCoPO₄ addition shows the best properties delivering 137 mA h g⁻¹ at a current density of 0.5C and remains at 132 mA h g⁻¹ with 98.5% charge/discharge efficiency after 100 cycles and 130 mA h g⁻¹ at a high current density of 20C, better than any other samples. This novel functional cathode material can be considered as a promising and useful choice for next generation LIB devices.