Nano Ceramic Coating on Polypropylene Separator for Safety-Enhanced Lithium Secondary Battery

고안전성 리튬이차전지 구현을 위한 나노 세라믹 코팅 분리막 제조 및 전기화학특성 분석

  • Received : 2017.01.10
  • Accepted : 2017.05.05
  • Published : 2017.05.31


Herein, we have fabricated an ultrathin aluminum oxide ($Al_2O_3$) coated PP separator by using a RF sputter deposition process. Approximately 20 nm thickness coating layer on the bare PP separator was formed at the power of 55 W for 2 minutes without thermal damage. Whereas only permeability of the coated separator was degraded slightly, other properties such as thermal stability, uptake amount of liquid electrolyte, and ionic conductivity were improved comparing to the bare PP separator. As a result, an only 20-nm-thick $Al_2O_3$ coating layer could improve the rate capability compared with a bare PP separator under a high current density.


Ceramic coated separator;RF sputter;Thermal stability;Lithium secondary battery


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Supported by : 한국연구재단