Facile cyclic ammonium salt with the smallest size for high performance electric double layer capacitors

Abstract The smallest cyclic ammonium salt reported to date, N,N- dimethylpyrrolidinium tetrafluoroborate (P 11 -BF 4 ), was successively synthesized using a synthesis route without metal ions and halogen ions, then investigated as the electrolyte with Propylene carbonate in EDLCs. The electrochemical characteristics of EDLCs assembled by 1 mol/L P 11 -BF 4 /PC paired with activated carbon electrodes were compared to traditional electrolytes. P 11 -BF 4 has proven to have superior voltage resistance by using cyclic voltammetry and constant current charge-discharge testing. Moreover, P 11 -BF 4 exhibits a more brilliant rate performance due to its high conductivity. These results demonstrate that P 11 -BF 4 is an ideal electrolyte to improve the energy density and power density of supercapacitors.