Figure 5
Capacitance and Li-insertion/extraction contributions to charge storage/delivery and the Ragone plot.
(a), Cyclic voltammetric responses for S/NP Cu/MnO2 hybrid bulk electrode at a scan rate of 5 mV s−1. The Li-insertion/extraction contribution is evaluated according to Eq. (1) and shown by the shaded region. (b), Capacitance and Li-insertion capacity for S/NP Cu/MnO2 electrode as a function of scan rate. (c), The Ragone plot of the constituent MnO2 nanoparticles in S/NP Cu/MnO2 electrode, comparing with the energy and power densities of the active materials in the composites of CNT/FePO43, functionalized LBL-CNTs14, graphene/V2O558 (only the active materials are included in the weight). The values of Li-ion nanoporous carbon/LiFePO414,59, LiNi0.5Mn0.5O214,60 and supercapacitive electrodes11,14 are also included for comparison.
