title: Formulation of ionic-liquid electrolyte to expand the voltage window of supercapacitors.
abstract: An effective method to expand the operating potential window (OPW) of electrochemical capacitors based on formulating the ionic-liquid (IL) electrolytes is reported. Using model electrochemical cells based on two identical onion-like carbon (OLC) electrodes and two different IL electrolytes and their mixtures, it was shown that the asymmetric behavior of the electrolyte cation and anion toward the two electrodes limits the OPW of the cell and therefore its energy density. Also, a general solution to this problem is proposed by formulating the IL electrolyte mixtures to balance the capacitance of electrodes in a symmetric supercapacitor.
authors: A. J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104 (USA).
authors: Katherine L
authors: KL
authors: Van Aken
authors: Majid
authors: M
authors: Beidaghi
authors: Yury
authors: Y
authors: Gogotsi
keywords: electrochemical capacitor; electrochemistry; energy density; ionic liquids; operating potential window