This paper is addressed on studying the electrolytes for electrical double layer capacitors with relatively high ionic conductivity and electrochemical stability for high energy density application. A systematic analysis of the electrochemical characteristics has been presented using spiro-(1,1′)-bipyrrolidinium tetrafluoroborate (SBP-BF4) with 1.5molL−1 (M) in variety of solvent compositions including propylene carbonate (PC), ethylene carbonate (EC) and dimethyl carbonate (DMC), while the solvent mixtures are PC+DMC (1:1 in volume) and PC+DMC+EC (1:1:1 in volume). The physical properties and electrochemical performance of SBP-BF4-based electrolytes are improved by tuning solvent mixtures compositions for high working voltage application. The binary solvent system of PC+DMC electrolyte exhibits lowest viscosity of about 3.14 mPas, while the ternary solvent system of PC+DMC+EC electrolyte exhibits highest conductivity of about 18.08mScm−1. The SBP-BF4/PC-based electrolytes display excellent upper voltage hold capability about 3.5V. The binary solvent system exhibits superior rate performance, when the charge cut-off voltage is lower than 3.2V. The ternary solvent system exhibits superior rate performance than that of other two solvent systems electrolytes, when the charge cut-off voltage is higher than 3.2V. The maximum energy density and power density of EDLCs using the ternary solvent system electrolyte are 41.5Whkg−1 and 17.0kWkg−1, respectively. The spiral cylindrical capacitors based on ternary solvent system electrolyte exhibits better cycle performance than that of other two solvent system electrolytes at the high working voltages.