1,2-butylene carbonate as solvent for EDLCs

The solvent 1,2-butylene carbonate (1,2-BC) displays a set of properties and a price comparable with that of propylene carbonate (PC). In this work we investigate the use of 1,2-BC in combination with the salt butyl-1-methylpyrrolidinium tetrafluoroborate (Pyr14BF4). We showed that the electrolyte 1.5 M Pyr14BF4 in BC displays good conductivities and viscosities, and that is use allows the realization of EDLCs with operative cell potential as high as 3.15 V. These high potential devices display good cycling stability at room temperature. At higher temperature their stability appears comparable of that of devices containing standard electrolytes.