Enhanced Electrochemical Performance of Ni-Rich Cathode Materials with Li_1.3Al_0.3Ti_1.7(PO₄)₃ Coating

Abstract

In this work, a fast ionic conductor, Li1.3Al0.3Ti1.7(PO4)3 (LATP), has been successfully coated on a Ni-rich LiNi0.8Co0.1Mn0.1O2 surface by an improved sol–gel method with postannealing at 575 °C. A series of electrochemical tests along with X-ray diffraction, scanning electron microscopy (SEM), energy dispersive spectrometry, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) are executed to study the physical characteristics and electrochemical properties of pristine LiNi0.8Co0.1Mn0.1O2 and LATP-coated LiNi0.8Co0.1Mn0.1O2 samples. Electrochemical results show that 0.5 wt % LATP-coated LiNi0.8Co0.1Mn0.1O2 exhibits the best electrochemical performance. In particular, 0.5 wt % LATP coating delivers great cycling stability with a capacity retention rate of 84.5% after 200 cycles at 2 C, while the pristine sample has a capacity retention rate of only 67.39%. The SEM-backscattered electron and TEM results of materials after cycling show that LATP coating can effectively improve the structural stability of the LiNi0.8Co0.1Mn0.1O2 cathode.