“…However, both extremely low wettability with liquid electrolytes and weak thermal stability have limited its further application in energy storage systems especially in hybrid electric vehicles (HEVs) areas [ 4 , 5 , 6 ]. To remedy the above defects, different kinds of separators were reported, such as polymers’ surface grafting modification of polyolefin separators [ 7 , 8 , 9 ], ceramic coating separators [ 6 , 10 , 11 , 12 , 13 , 14 ], nonwoven membrane [ 15 , 16 , 17 , 18 , 19 , 20 ] and polymer electrolyte used as separators [ 21 , 22 , 23 , 24 , 25 , 26 ].…”