Abstract
This work deals with the comparative analysis of fluoride coatings, i.e., 5 wt.% AlF3 and LiF, applied as surface layer of Li-rich Li1.2Ni0.13Co0.13Mn0.54O2 (LNCM) layered oxides synthesized via facile and cost-effective sol–gel route. The detailed structural and morphological characterizations demonstrate that AlF3 and LiF deposits have a pivotal role in enhancing the electrochemical properties of LNCM. These electrochemical properties include galvanostatic charge–discharge (GCD), differential capacity (dQ/dV), electrochemical impedance spectroscopy (EIS), and area-specific impedance (ASI). A much lower decay of the discharge capacity of 0.22 and 0.25 mAh g−1 per cycle was obtained for AlF3- and LiF-coated LMNC, respectively, after 100 charge/discharge cycles at 0.1 C compared with 0.42 mAh g−1 per cycle for pristine LNCM. Results evidence the non-evolution of the charge transfer resistance, enhanced lithium-ion kinetics and stabilization of electrode/electrolyte interface during cycling.