Tailoring the performance of the LiNi0.8Mn0.1Co0.1O2 cathode using Al2O3 and MoO3 artificial cathode electrolyte interphase (CEI) layers through plasma-enhanced atomic layer deposition (PEALD) coating

Abstract

The Ni-rich layered oxide cathode has shown high energy density, proper rate capability, and longevity of the rechargeable battery, while poor stability and capacity fading are assumed to be its common cons. To address this obstacle, prospective cathode materials are synthesized by integrating the lithium transition metal oxides with an artificial cathode electrolyte interphase (CEI) layer. Herein, plasma-enhanced atomic layer deposition (PEALD) is employed to coat the LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) electrode with Al₂O₃ and MoO₃. The combined results from morphological examinations revealed the formation of uniform Al₂O₃ and MoO₃ sheets after 200 cycles of PEALD coating. Consistent results from the XRD analysis demonstrate that Al₂O₃ and MoO₃ artificial CEIs can reduce Li–Ni mixing. The cyclic voltammetry tests show the oxidation–reduction kinetic. The modified NMC811 structures with Al₂O₃ and MoO₃ represent a remarkable improvement in terms of capacity retention. The coated cathode with Al₂O₃ clearly outperforms the modified configuration with MoO₃ concerning ionic conductivity, charge/discharge reversibility, and capacity retention. The promising results obtained in this study open the possibility of synthesizing Ni-rich cathodes with enhanced electrochemical performance.