Dry Particle Fusion Assisted Ceramic Coatings for High Nickel Cathode for Scalable 18650 Lithium-Ion Batteries

Abstract

Over the last several decades, energy storage has become one of the central tools for facilitating energy transformation from (electro)chemical reactions to electricity. Rechargeable lithium-ion batteries (LIBs) are among the most popular and promising mature technologies for portable electronics, grids, and transportation. The cathode, a working horse, mainly determines the overall capacity among the various components. Off-late layered Li-rich or Ni-rich material plays a vital role, especially Ni-rich LiNixMnyCo1-x-yO2; x ≥ 0.8 (NMC) get significant attention. However, it is unfortunate that such Ni-rich cathode materials encountered severe capacity degradation and poor thermal instability concerning the Ni-concentration. Several strategies have already been proposed to mitigate those issues, including electrolyte additive, cation doping, and coating or surface modification. Among them, the modification of the cathode surface, like core-shell construction, is a practical approach. Herein, a core-shell architecture was achieved by employing the cost-effective dry particle fusion method over Ni-rich (LiNi0.8Mn0.1Co0.1O2 (NMC811), where the nano aluminum oxide was used as a shell material with an average thickness of 150-200 nm. Such NMC@alumina core-shell exhibits excellent cycling stability compared with pristine NMC811. The chemical lithium diffusion coefficient was calculated using galvanostatic (GITT) and the potentio-dynamics process. Additionally, the control of parasitic reaction between the delithiated cathode and electrolyte was analyzed using the in-situ Differential Electrochemical Mass Spectrometry (DEMs) technique, where the onset potential and the amount of gas generated are compared with pristine material.