Lithium battery using sulfur infiltrated in three-dimensional flower-like hierarchical porous carbon electrode

Three dimensional, flower-like hierarchical porous carbon (FPC) and its CO2-activation (AFPC) are reported as sulfur-hosting matrixes in Li/S battery. The composites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms as well as by galvanostatic cycling and electrochemical impedance spectroscopy (EIS) in lithium-cell. Both samples show well defined micrometric morphology and a sulfur content as high as 66% expected to reflect into rather high practical energy density of the electrode in lithium-sulfur battery. The lithium sulfur cell using the FPC-S composite exhibits at 25 degrees C a moderate cycling stability with delivered capacity ranging from 1000 to about 610 mAh g(-1) upon 50 cycles at 100 mA g(-1). The AFPC-S composite reveals increased cycling stability and delivers a capacity ranging from 1000 to 680 mAh g(-1). Improved capacity is achieved by slightly increasing the temperature, as demonstrated by cycling the FPC-S at 35 degrees C using a current as high as 500 mA g(-1). The excellent rate capability of the electrode is associated to the carbon texture and morphology that significantly lower the cell resistance, as indeed demonstrated by EIS measurement upon cycling. (C) 2016 Elsevier B.V. All rights reserved.