In-situ UV cured acrylonitrile grafted epoxidized natural rubber (ACN-g-ENR) - LiTFSI solid polymer electrolytes for lithium-ion rechargeable batteries

摘要

Solid polymer electrolytes (SPEs) of newly synthesized acrylonitrile grafted epoxidized natural rubber (ACN-gENR) were successfully prepared with lithium bis(trifluoromethanesulfonyl)imide salt (LiTFSI) via UV curing technique. The highest ionic conductivity of the SPEs was accomplished at 40 wt% LiTFSI with conductivity value of 1.1 x 10-6 S cm- 1 at room temperature. Further analysis indicates that the ion transport of the SPEs follows the VTF model. Chronoamperometry study estimated low lithium ions contribution to overall ionic conductivity (ca. 3%). A persuasive value of 2.7 V was obtained from the electrochemical stability. It is suitable to be applied in lithium-ion rechargeable batteries. An additional investigation by infrared (FTIR) spectroscopy revealed the polymer salt complexation occurred between Li+ of dopant salt with the ether group (C-O-C) oxygen of the epoxy ring. The inclusion of LiTFSI salts was decreased crystallinity, nevertheless, the glass transition temperature (Tg) and thermal stability, as well as the dynamic mechanical properties of the polymer electrolytes were enhanced. All in all, the initial electrochemical characteristics showed a promising potential of ACN-g-ENR host polymeric electrolyte to be used in lithium-ion storage energy applications.