The tunable electrochemical performances of carbon fluorides/manganese dioxide hybrid cathodes by their arrangements

The study investigates the effects of arrangements to the electrochemical performances of carbon fluorides (CFx)/manganese dioxide (MnO2) hybrid cathodes. When CFx and MnO2 are in parallel arrangement (denoted as CFx parallel to MnO2), the hybrid cathode exhibits the best electrochemical performances than other types of arrangements, such as the mixed or stacked types. Based on the various electrochemical measurements, such as impedance spectra and galvanostatic intermittent titration technique, the charge transfer takes place at the interface of MnO2 and CFx particles because of the special arrangement in the CFx parallel to MnO2 hybrid cathode, in which the continuous MnO2 phase guarantees and facilitates the lithium ions transfer from electrolyte to current collector due to the lower charge transfer resistance. Therefore, CFx parallel to MnO2 exhibits the best rate capability, and the maximum delivered power density is up to 6599 W kg(-1) at 5C, associated with the energy density of 1814 Wh kg(-1). (C) 2014 Elsevier B.V. All rights reserved.