Study on the surface modification of spinel LiNi0.45Cr0.1Mn1.45O4
Journal
Journal of Alloys and Compounds
Journal Volume
821
Date Issued
2020
Author(s)
Abstract
A amorphous compound Li–Al–Ti–O is coated on the surface of spinel LiNi0.45Cr0.1Mn1.45O4. Different from other coatings, the coating layer and the bulk material are not simply connected. There is a transition region between the coating layer and the bulk material, in which no sudden change of lattice emerges. High-resolution transmission electron microscopy (HRTEM) shows that lattice matching is formed at the contact region between coating layer and bulk material. The Cr K-edge XANES spectra show that the local structure of Cr has not changed before and after coating. According to the electrochemical impedance measurement, the diffusion coefficient of lithium ion has no much changes after coating. Compared with the pristine materials, this coated materials exhibits improved cycle performance. After 700 charging and discharging cycles, the capacity retention rate reaches over 83%, and the Coulomb efficiency of each cycle is 99.5%. This coating structure undoubtedly increases the bonding strength between the coating layer and the bulk material, and also reduces the resistance of lithium ions passing through transition region. This coating lays a good foundation for the practical application of the spinel LiNi0.45Cr0.1Mn1.45O4. ? 2019 Elsevier B.V.
Subjects
Chromium; Coated materials; Diffusion coatings; High resolution transmission electron microscopy; Lithium; Materials handling equipment; Surface treatment; Amorphous compounds; Capacity retention; Charge-discharge property; Coating structures; Electrochemical impedance measurements; Pristine materials; Spinel LiNi0.45Cr0.1Mn1.45O4; Structure characteristic; Aluminum coatings
SDGs
Type
journal article