Abstract
For its superior heat resistance and high liquid preserving ability, nonwoven with ceramic coating have been widely focused in the field of EV/HEV battery separator. In this paper, five separators with different ceramic coating (Al2O3, SiO2, YSZ, BaTiO3 and LixLa1-xTiO3) were prepared. Then, their morphologies were characterized by SEM. Thermal properties were analyzed under the standard of SAE J 2983-2012. Besides, proper electrolytes were chosen by wettability and electrolyte-retention test. Moreover, the electrochemical properties of them were characterized by linear sweep voltammetry (LSV) and galvanostatic method after assembling with the chosen electrolyte. Results show that those separators are successfully prepared and the incorporation of PET enhances the mechanical property, thermal shrinkage property and incombustible property. Cells performance tests show that the cell with SiO2-PET separator has the highest capacity retention when discharged at 4C and the best cycling capacity retention. In general, the ceramic coating PET is potentially extendable to high-performance separator for high power lithium ion battery with enhanced safety and performance. This article may provide a practical technical support for the application of ceramic-PET separators in the field of EV and HEV batteries.
KEYWORDS Lithium-ion battery, separator, ceramic coating, PET nonwoven, electrolyte matching