Leš, K.K.LešSchönewerk, J.J.SchönewerkGlenneberg, JensJensGlennebergJordan, C.S.C.S.Jordan2022-12-012022-12-012022https://publica.fraunhofer.de/handle/publica/42945910.1007/s10853-022-07431-12-s2.0-85134067070he performance of solid polymer electrolytes is characterized by lower ionic conductivity than conventional liquid electrolytes but provides advantages in terms of operational safety. A quasi-solid polymer electrolyte (QSPE) based on a new plasticizer 4,7,10,13-tetraoxahexadecane-1,16-dinitrile (bCN-PEG4) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) incorporated into a polyacrylates matrix was successfully prepared via UV-induced copolymerization. The matrix consists of units of trimethylolpropane ethoxylate triacrylate (ETPTA), poly(ethylene glycol) diacrylate (PEGDA), and the monoacrylate poly(ethylene glycol) methyl ether acrylate (mPEGa). The QSPE containing 55 wt% bCN-PEG4 exhibits highly uniform morphology, thermal stability > 200 °C, ionic conductivity of 1.8 × 10−4 S cm−1 at 30 °C, and 1.3 × 10−3 S cm−1 at 80 °C, coupled with very high electrochemical stability (> 5 V vs. Li/Li+) and a low glass transition temperature (− 55.7 °C). A cycling experiment in a Li/QPSE/Li cell setup demonstrated the compatibility toward lithium metal additionally. The bCN-PEG4 offers an overall satisfying performance as a plasticizer in a poly(ethylene oxide)-based solid polymer electrolyte. The new QSPE is an alternative to dinitrile-based (e.g., succinonitrile) or glycol ether-based (e.g., tetraglyme) plasticizers with application potential in high-voltage lithium-ion batteries.enjournal article