Protic and Aprotic Acetate‐Based Ionic Liquids as Electrolytes for Electrical Double Layer Capacitors

Abstract This work presents the synthesis, characterization, and application of a series of aprotic and protic acetate‐based ionic liquids (AcILs). These cost‐effective ILs can be obtained through a simple synthesis and display good transport and thermal properties. When used as electrolytes in electrical double‐layer capacitors (EDLC) they enable the fabrication of devices with an operating voltage as high as 1.8 V, which display very good cycling and float stability. The performance of these devices can be tuned by adjusting the water content of the ILs. Notably, EDLCs containing AcILs can also be realized using aluminum current collectors.