Ionic liquid additive for lithium-ion battery
An ionic liquid for adding to an electrolyte of a lithium-ion battery, the ionic liquid comprises a compound with a dual core structure having the general formula (I): wherein each of cationic group X 1 and X 2 are heterocyclic aromatic and amine.
1. A lithium ion battery comprising a positive electrode, a negative electrode, a separator, an electrolyte and an ionic liquid, wherein an overall amount of ionic liquid added to the electrolyte is 0.1-15 wt.%, the ionic liquid comprising a compound with a dual core structure X 1 -Y-W and anionic group Z 1 ,
wherein W is an aromatic group, and Y is a C3-C10 alkyl, sulfonyl, carbonic acid, ether, ketone or ester group,
wherein the compound X 1 YW is selected from the group consisting of:
Benzyl-2-(1-methylpyrrolidinium 1-yl) ethyl ether,
Benzyl-4-(1-methylpyrrolidinium 1-yl) butyl ether,
1-(1-Benzoyl)-1-methyl pyrrolidinium,
1-(2-Phenacyl)-1-methyl pyrrolidinium,
1-(Furan 2-yl)-1-methyl pyrrolidinium,
1-(butyl furan 2-yl)-1-methyl pyrrolidinium,
1-(2-Furoyl)-1-methyl pyrrolidinium,
1-Benzensulfonyl-1-methyl pyrrolidinium, and
1-p-Toluenesulfonyl-1-methyl pyrrolidinium; and
wherein Z 1 is selected from the group consisting of PF 6 - (hexafluorophosphate), POF 2 (difluorophosphate), BF 4 - (tetrafluoroborate), B(C 2 O 4 ) 2 - (BOB - , bis(oxalato) borate), BF 2 (C 2 O 4 ) - (ODFB - , difluoro(oxalato)borate), CF 3 BF 3 - (trifluoromethyltrifluoroborate), (FSO 2 ) 2 N - (FSI - , bis(fluorosulfonyl)imide), (CF 3 SO 2 ) 2 N - (TFSI - , bis(trifluoromethane)sulfonamide), CH 3 SO 4 - and (MeSO 4 - , methyl sulfate).