Adiponitrile-based electrochemical double layer capacitor

In this paper we report on the use of 0.7 M Et4NBF4 in ADN as electrolyte in EDLCs. 0.7 M Et4NBF4 in ADN displays a wide electrochemical stability window and promising values of conductivity and viscosity. Using this electrolyte it is possible to realize EDLCs with an operative voltage as high as 3.75 V. At RT, these high voltage EDLCs display high coulombic efficiencies, low ESRs and high specific capacitances stable for several thousands of cycles. The wide electrochemical stability of ADN contributes to preserve the integrity of the electrolyte at potentials in which other conventional organic electrolytes (e.g. ACN) are normally subject to deterioration and/or decomposition processes. Thanks to this intrinsic stability, EDLCs containing 0.7 M Et4NBF4 ADN as electrolyte display high capacitance retention over 35,000 cycles carried out with cell voltage as high as 3.5 V. (C) 2011 Elsevier B.V. All rights reserved.