A Stable High Capacity Lithium-Ion Battery Using a Biomass-Derived Sulfur-Carbon Cathode and Lithiated Silicon Anode.

A full lithium-ion sulfur cell with a remarkable cycle life is achieved by combining environmentally a biomass-derived sulfur-carbon cathode and a pre-lithiated silicon oxide anode. X-ray diffraction (XRD), Raman spectroscopy, energy dispersive spectroscopy (EDS), and thermogravimetry (TGA) of the cathode evidence the disordered nature of the carbon matrix in which sulfur is uniformly distributed with a weight content as high as 75 %, while scanning and transmission electron microscopy (SEM, TEM) reveal the micrometric morphology of the composite. The sulfur-carbon electrode exhibits in lithium half-cell a maximum capacity higher than 1200 mAh gS-1 , reversible electrochemical process, limited electrode/electrolyte interphase resistance, and a rate capability up to C/2. The material shows a capacity decay of about 40% with respect to the steady state value over 100 cycles, likely due to the reaction with the lithium metal of polysulfides or impurities including P detected in the carbon precursor. Therefore, the replacement of the lithium metal with a less challenging anode is suggested, and the sulfur-carbon composite is subsequently investigated in the full lithium-ion sulfur battery employing a Li-alloying silicon oxide anode. The full-cell reveals an initial capacity as high as 1200 mAh gS-1 , a retention increased to more than 79% for 100 galvanostatic cycles, and of 56 % over 500 cycles. The data reported herein well indicate the reliability of energy storage devices with extended cycle life employing high-energy, green and safe electrode materials.