Surface modification of Ni-rich LiNi0.8Co0.1Mn0.1O2 cathode materials via a novel mechanofusion alloy route

Abstract

This study aimed to prepare a composite coating material comprising a solid ionic conductor of lithium aluminum titanium phosphate (Li1.4Al0.4Ti1.6(PO4)3, LATP) and porous carbon through a sol-gel method. LiNi0.8Co0.1Mn0.1O2 (LNCM811) cathode material with dual-functional composite conductors (i.e., LATP@porous carbon), denoted as LATP-PC, was prepared. The dry-coating method, also called the “mechanical-fusion alloy route,” was used to modify Ni-rich LNCM811 cathode materials. X-ray diffraction (XRD), micro-Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed that the LATP ionic conductor generated herein was uniformly deposited on 3D porous carbon and served as a dual-functional composite coating on LNCM811. Furthermore, the capacity retention of LATP-PC@LNCM811 was approximately 85.57% and 80.86% after 100 cycles at −20 °C and 25 °C, respectively. By contrast, pristine LNCM811 had the capacity retention of 78% and 74.96% at −20 °C and 25 °C, respectively. Furthermore, the high-rate capability of the LATP-PC@LNCM811 material was markedly enhanced to 169.81 mAh g−1 at 10C relative to that of pristine LNCM811, which was approximately 137.67 mAh g−1. The electrochemical performance of LNCM811 was enhanced by the uniform dual-conductive composite coating. The results of the study indicate that the LATP-PC@LNCM811 composite material developed herein is a potentially promising material for future high-energy Li-ion batteries.