title: A high performance hybrid capacitor with Li2CoPO4F cathode and activated carbon anode.
abstract: For the first time, we report the possibility of utilizing Li2CoPO4F as a novel cathode material for hybrid capacitor applications. Li2CoPO4F powders were prepared by a conventional two-step solid state method. A hybrid cell was fabricated using Li2CoPO4F as the cathode along with activated carbon (AC) as the anode in 1 M LiPF6 dissolved in 1 : 1 EC/DMC electrolyte and its electrochemical properties were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and constant current charge-discharge (C-D) techniques. The Li2CoPO4F/AC cell is capable of delivering a discharge capacitance of 42 F g(-1) at 150 mA g(-1) current density within 0-3 V region having excellent coulombic efficiency of over 99% even after 1000 cycles. Furthermore, the Li2CoPO4F/AC cell exhibited excellent rate performance with an energy density of ~24 W h kg(-1) at 1100 mA g(-1) current and maintained about 92% of its initial value even after 30,000 C-D cycles. Electrochemical impedance spectroscopy was conducted to corroborate the results that were obtained and described.
authors.affiliation: Faculty of Applied Chemical Engineering, Chonnam National University, Gwangju 500-757, Korea. leeys@chonnam.ac.kr.
authors.forename: K
authors.initials: K
authors.lastname: Karthikeyan
authors.forename: S
authors.initials: S
authors.lastname: Amaresh
authors.forename: K J
authors.initials: KJ
authors.lastname: Kim
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: K Y
authors.initials: KY
authors.lastname: Chung
authors.forename: B W
authors.initials: BW
authors.lastname: Cho
authors.forename: Y S
authors.initials: YS
authors.lastname: Lee