Microstructures and electrochemical performances of TiO2-coated Mg–Zr co-doped NCM as a cathode material for lithium-ion batteries with high power and long circular life

Abstract

To enhance the electrochemical properties of LiNi_1/3Co_1/3Mn_1/3O₂ (NCM) materials for lithium-ion batteries (LIBs), TiO₂-coated Mg–Zr co-doped NCM cathode materials (MZT-NCM) were fabricated via a two-step solid-state method using Mg(OH)₂, Zr(OH)₄ and Ti(OH)₃ as Mg, Zr and Ti sources, respectively. The electrochemical characteristics were assessed by the hybrid pulse power characteristic (HPPC) test, galvanostatic charge–discharge, EIS and CV test. Compared with NCM, the electrochemical properties of MZT-NCM as a cathode material in a pouch-cell were enhanced, especially high power performance and the stability of long cycle life. The MZT-NCM exhibits an excellent power performance of 2051 W, compared to that of the NCM, which only achieves 1736 W at 50% state of charge (SOC). Furthermore, the MZT-NCM samples deliver an outstanding capacity retention rate of 91.10% after 7000 cycles at 3C, which is nearly 10% higher than that of NCM. The modification strategy has a positive effect on the electrochemical characteristics of NCM cathode materials, which is expected to provide meaningful guidance for developing high power and long cycle life LIBs.