Enhancement of Thermal Stability and Cycling Performance of Lithium-Ion Battery at High Temperature by Nano-ppy/OMMT-Coated Separator

Authors

Shuo Yang, Tianjin University
Huiya Qin, Tianjin University
Xuan Li, Tianjin University
Hui Jun Li, University of WollongongFollow
Pei Yao, Tianjin UniversityFollow

RIS ID

112863

Publication Details

Yang, S., Qin, H., Li, X., Li, H. & Yao, P. (2017). Enhancement of Thermal Stability and Cycling Performance of Lithium-Ion Battery at High Temperature by Nano-ppy/OMMT-Coated Separator. Journal of Nanomaterials, 2017 6948183-1-6948183-10.

Abstract

Nanopolypyrrole/organic montmorillonite- (nano-ppy/OMMT-) coated separator is prepared by coating nano-ppy/OMMT on the surface of polyethylene (PE). Nano-ppy/OMMT-coated separator with three-dimensional and multilayered network structure is beneficial to absorb more organic electrolyte, enhancing the ionic conductivity (reach 4.31 mS ^. cm^-1). Meanwhile, the composite separator exhibits excellent thermal stability and mechanical properties. The strong covalent bonds (Si-F) are formed by the nucleophilic substitution reaction between F− from the thermal decomposition and hydrolysis of LiPF₆ and the covalent bonds (Si-O) of nano-ppy/OMMT. The Si-F can effectively prevent the formation of HF, POF₃, and LiF, resulting in the inhibition of the disproportionation of Mn³⁺ in LiNi_1/3Co_1/3Mn_1/3O₂ material as well as reducing the internal resistance of the cell. Therefore, the nano-ppy/OMMT-coated separator exhibits outstanding capacity retention and cycling performance at 80°C.