Suppressed voltage decay and improved electrochemical performance by coating LiAl5O8 on the surface of Li1.2Mn0.54Ni0.13Co0.13O2

Understanding the Role of Alumina (Al2O3), Pentalithium Aluminate (Li5AlO4), and Pentasodium Aluminate (Na5AlO4) Coatings on the Li and Mn‐Rich NCM Cathode Material 0.33Li2MnO3·0.67Li(Ni0.4Co0.2Mn0.4)O2 for Enhanced Electrochemical Performance

“…[ 23–25 ] Heat treatment with inorganic materials or carbo‐thermal reduction has also been carried out for achieving improved redox kinetics and superior electrochemical cycling behavior. [ 26,27 ] One of the promising approaches is surface coatings using metal oxides like TiO 2 , [ 28 ] ZrO 2 , [ 29 ] Al 2 O 3 , [ 28,30,31 ] and Li‐ion conducting materials, for instance, lithium aluminate, [ 32–35 ] lithium zirconate, [ 29 ] sodium aluminate. [ 36,37 ] These coatings effectively lessen the undesired detrimental surface reactions of solutions species and HE‐NCM cathodes, diminishing thus TMs dissolution upon prolonged cycling.…”

“…[ 28,30,31 ] In contrast, the lithium aluminate coatings on these materials bring out the synergistic effect of surface protection due to high chemical stability and faster Li‐ion transport kinetics by reducing the cell impedance upon cycling. [ 32–35 ] The positive impact of sodium aluminate coating on layered cathode materials like LiCoO 2 [ 36 ] or Ni‐rich material (NCM523) [ 37 ] has also been studied where the formation of 2D ion diffusion channels [ 40 ] upon charging has been accounted for the superior electrochemical performances. It is important to emphasize that reducing HF concentrations in the electrolyte solution upon the consecutive electrochemical cycling were also observed for cells comprising alumina coated cathodes [ 41,42 ] as the alumina‐based coatings undergo chemical reactions with harmful HF forming a variety of AlO x F y H z species (including AlF 3 , AlO x H y ), what means effective scavenging of HF.…”

Li1.2Mn0.54Ni0.13Co0.13O2 nanosheets with porous structure as a high-performance cathode material for lithium-ion batteries

“…It can be seen that the nanosheets in this work deliver the comparable discharge capacities with those reported in the ref. 34–39 . It demonstrates that the 2D morphology and porous structure of the nanosheets facilitate the achievement of their high discharge capacities in lithium-rich layered oxide cathodes.…”

Dual Substitution Strategy in Co-Free Layered Cathode Materials for Superior Lithium Ion Batteries

“…They induce drawbacks in LRMs, such as the inferior rate and cycle performance as well as a severe voltage decay. − However, the O 2 formed in the bulk is captured and can be restored to form O 2– again during discharge, which causes voltage hysteresis in the first cycle of LRMs . It has been suggested that the voltage as well as decay of LRMs is related to the activation of low-voltage redox pairs, such as Co 2+ /Co 3+ and Mn 3+ /Mn 4+ , which are due to the oxygen loss . In short, the structural instability and phase transition during the cycle are closely related to the instability of the lattice oxygen, and the voltage decay will lead to a continuous capacity loss in the cycling process and increase the difficulty for battery design and management. − …”