Improved Electrochemical Performance of LiNi_0.8Co_0.1Mn_0.1O₂ Cathode Materials Induced by a Facile Polymer Coating for Lithium-Ion Batteries

Abstract

Ni-rich LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM) material has attracted intense attention because of the capacity and cost advantages. However, the poor cycling performance hampers the further development of NCM. As a coating layer, polysiloxane can improve the electrochemical properties of the NCM by eliminating remaining H 2 O on the surface of NCM and the reaction between HF in electrolyte and NCM, inhibiting the interfacial side reactions. Compared with the pristine NCM, the cycling performance of the NCM cathode coated with polysiloxane is significantly improved. The capacity retention of NCM coated with polysiloxane is 91.5% at 1 C after 120 cycles, while pristine NCM only maintains 71.4%. This study provides a method to alleviate the effects of interfacial side reactions and HF corrosion on NCM performance degradation after many cycles.

Coating of a Novel Lithium-Containing Hybrid Oligomer Additive on Nickel-Rich LiNi0.8Co0.1Mn0.1O2 Cathode Materials for High-Stability and High-Safety Lithium-Ion Batteries

“…Furthermore, it is easy to scale up for electrode slurry production. Particularly, in this work, the high polarity and strong affinity of the BTJ-L oligomer additive to NCM811 transition-metal oxide surfaces can facilitate the formation of a highly continuous porous film with a thickness on the nanoscale (4–7 nm) on the surface of active cathode materials (Figure c), thereby leading to satisfactory cycling performance, in comparison with recent advanced works − (Table ). In addition, this desirable characteristic in combination with its thermal polymerization at high temperature (Figure c) to form a dense polymer coating with highly cross-linked structure can impart high safety to LIBs subject to the thermal runaway threat.…”

Bifunctional surface modification coupled with oxygen defect engineering enables high performance Li-rich cathodes

“…It is noted here that the degree of deterioration is not uniform owing to differences in particle surface inhomogeneity and particle crystallographic orientation. [12][13][14][15] Therefore, the construction of a stable layer of interface on the material surface is benecial to stabilize the material structure, mitigate the release of oxygen from the surface and inhibit the side reactions occurring on the material surface.…”

Fundamental Understanding of the Effect of a Polyaniline Coating Layer on Cation Mixing and Chemical States of LiNi0.9Co0.085Mn0.015O2 for Li-Ion Batteries

“…Coating technology is one of the strategies for the physical protection of the cathode surface and for controlling the CEI layer thickness. Polymer materials with high conductivity and flexibility are used as protective barriers for cathodes, and many studies have been conducted on polymer coating layers, such as polyaniline (PANi), polypyrrole, polysiloxane, polyacrylonitrile, etc. Especially, PANi has special advantages over other polymers, including high thermal stability, a simple synthesis method, and the moderation ability of polarity between the cathode and the electrolyte, which suppresses polarization and interface resistance with a stable oxidation state.…”