The performances obtained with methoxypropionitrile/ethylene carbonate mixture based electrolytes were investigated in supercapacitor application. The incorporation of methoxypropionitrile allows a good compromise between electrochemical performances and safety issue to be exhibited in a wide temperature range. This improvement is associated with the decrease of electrolyte viscosity without compromising the salt solubility and dissociation. The highest conductivity values, 20 mS cm(-1) at 30 degrees C compared to 14 mS cm-1 in PC (propylene carbonate), were obtained with both 1 M tetraethylammonium tetrafluoroborate (TEABF(4)) and spiro-(1,1')-bipyrrolidium tetrafluoroborate (SBPBF4) salts. Bulk liquid state was conserved for these electrolytes in a wide temperature range. Then, interesting electrolyte conductivities were obtained at low temperature (5.2 mS cm(-1) at 25 degrees C) which is twice that of PC + TEABF(4) 1 M electrolyte at the same conditions. Moreover, the capacitor performance of EC/MP based electrolyte is better than PC one at room temperature. (C) 2013 Elsevier Ltd. All rights reserved.