Impact of LiTi2(PO4)3 coating on the electrochemical performance of Li1.2Ni0.13Mn0.54Co0.13O2 using a wet chemical method

NASICON-type solid-state electrolyte has been reported to improve the structural and electrochemical stability of high nickel positive electrode materials; however, the impact of NASICON-type solid-state electrolyte on the performance of lithium-rich cathode has been barely studied. In this work, various contents of LiTi2(PO4)3 (LTP)-coated Li1.2Ni0.13Mn0.54Co0.13O2 have been made via a wet chemical method followed by sintering at 550 °C for 3 h. Those modified materials failed to show improvement in electrochemical properties including specific capacity, coulombic efficiency (CE), rate capability, and cycle life compared with uncoated material. Thick LTP coating even decreases the average discharge voltage and increases the impedance and voltage hysteresis of cells. XRD, TEM, and SAED images revealed non-uniform coating with multiple components including LiTi2(PO4)3, TiP2O7, and TiO2. This work suggests LTP coating on Li1.2Ni0.13Mn0.54Co0.13O2 using a wet chemical method might be challenging and need to be carefully carried out.