Enhanced electrochemical properties of lithium-reactive V2O5 coated on the LiNi0.8Co0.1Mn0.1O2 cathode material for lithium ion batteries at 60 °C

Abstract

The cycling performance of a lithium-reactive V₂O₅ coated LiNi_0.8Co_0.1Mn_0.1O₂ material at 60 °C is substantially improved by a wet-coating process. The V₂O₅-coated materials are obtained from drying a mixture consisting of NH₄VO₃ and LiNi_0.8Co_0.1Mn_0.1O₂ powders dispersed in ethanol at 85 °C followed by firing at 300 °C for 5 h. The morphology of the V₂O₅-coated LiNi_0.8Co_0.1Mn_0.1O₂ particle synthesized by this coating process is characterized by SEM, TEM and EDX analysis. The V₂O₅ layer is homogeneously coated onto the particle and the coating thickness was found to be approximately 10–30 nm. The capacity improvement at 60 °C is related to the fact that the highly distributed V₂O₅ near the surface diminishes the side reactions between the cathode and electrolyte. Moreover, the improvements may also benefit from the unique structure and properties of V₂O₅.