writer：Xuewen Yu, Dianbo Ruan, Changcheng Wu, Jing Wang, Zhiqiang Shi*
keywords：Spiro-(1,10)-bipyrrolidinium tetrafluoroborate, Electrical conductivity, Withstand voltage, Activated carbon electrode, Supercapacitors
source：期刊
specific source：Journal of Power Sources
Issue time：2014年

A novel quaternary ammonium salt based on spiro-(1,10)-bipyrolidinium tetrafluoroborate (SBP-BF4) has been synthesized and dissolved in propylene carbonate (PC) with 1.5 mol/L (M) concentration for electric double-layer capacitors (EDLCs). The physic-chemical properties and electrochemical performance of SBP-BF4/PC electrolyte are investigated. Compared with the standard electrolyte1.5 MTEMABF4 inPC, the novel SBP-BF4/PC electrolyte exhibited much better electrochemical performance due to its smaller cation size, lower viscosity and higher conductivity. The specific discharge capacitance of activated carbon electrode based EDLCs using SBP-BF4/PC electrolyte is120 F/g, the energy density and power density can reach 31 kW/kg and 6938 W/kg, respectively, when the working voltage is 2.7 V and current density is 50 mA/g. The withstand voltage of activated carbon based EDLCs with SBP-BF4/PC electrolyte can reach to 3.2 V, where the stable discharge capacitance and energy density are121 F/g and 43 Wh/kg, respectively.