Polyamide-Imide Binder with Higher Adhesive Property and Thermal Stability as Positive Electrode of 4V-Class Lithium-Ion Batteries.

Polyamide-imide (PAI) was used as the advanced binder for the 4V-class LiNi_1/3Co_1/3Mn_1/3O₂ (LNCMO) electrode. The PAI binder showed a higher adhesive property and thermal stability than the polyvinylidene difluoride (PVdF) ones. The cycling stability at 60°C for the LNCMO electrodes was improved by using the PAI binder. The capacity retention ratio after 500 cycles at the 5C-rate was 23% for the electrode using the PVdF binder, whereas that increased to 80% for the electrode using the PAI one. A part of the LNCMO particle surface was coated by a thin layer of the PAI binder based on SEM observations, and EDS and XPS analyzes. The PAI layer was effective for suppressing the electrolyte decomposition on the particle surface and decreasing the generated total heat, thus showing the high thermal stability of the LNCMO electrode. [ABSTRACT FROM AUTHOR]