Ceramic composite separators coated with moisturized ZrO(2) nanoparticles for improving the electrochemical performance and thermal stability of lithium ion batteries.
We introduce a ceramic composite separator prepared by coating moisturized ZrO2 nanoparticles with a poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-12wt%HFP) copolymer on a polyethylene separator. The effect of moisturized ZrO2 nanoparticles on the morphology and the microstructure of the polymeric coating layer is investigated. A large number of micropores formed around the embedded ZrO2 nanoparticles in the coating layer as a result of the phase inversion caused by the adsorbed moisture. The formation of micropores highly affects the ionic conductivity and electrolyte uptake of the ceramic composite separator and, by extension, the rate discharge properties of lithium ion batteries. In particular, thermal stability of the ceramic composite separators coated with the highly moisturized ZrO2 nanoparticles (a moisture content of 16 000 ppm) is dramatically improved without any degradation in electrochemical performance compared to the performance of pristine polyethylene separators.
Advanced Batteries Research Center, Korea Electronics Technology Institute, 68 Yatap-dong, Bundang-gu, Seongnam 463-816, Republic of Korea. parkms@keti.re.kr.
Ki Jae
KJ
Kim
Hyuk Kwon
HK
Kwon
Min-Sik
MS
Park
Taeeun
T
Yim
Ji-Sang
JS
Yu
Young-Jun
YJ
Kim