Preparation And Electrochemical Performance Of Elemental Sulfur Composite Cathode Materials For Rechargeable Lithium Batteries

In the beginning of the paper, the present study and the actual applied complexion of cathode materials for the rechargeable lithium batteries were reviewed in detail. Our researchful purpose is the highest capacity sulfur material. We reviewed the market and technology development of sulfur positive material, compare advantage and disadvantage of sulfur positive material manufactured with different methods. Elemental sulfur is a kind of most promising cathode material for the next generation lithium batteries, due to its the highest specific capacity, abundant resources, and low toxicity. However, the insulating nature of sulfur and polysulfides and the loss of polysulfides in the liquid organic electrolyte make lithium-sulfur batteries have very low positive active material utilization and poor cyclability.In the study, three types of nano particle sulfur composite materials were designed and prepared, that is, conductive-polymer/sulfur composites and /nano-porous materials and /nano-catalyzed sulfur composite material , which can be used as advanced cathode materials for rechargeable lithium batteries. The structures and components of the resulting composites are systematically measured by means of H-NMR, FTIR, XRD, DSC, SEM, element analysis and BET. The cathodes, which were made of above-mentioned three composites, and gel polymer electrolytes were used for lithium batteries. The charge and discharge performances of different composites were studied by the charge and discharge; The structures of composites were characterized by SEM; The electrochemical properties of sulfur positive materials were characterized by cyclic voltammetry and EIS. We studied the charge process, discharge process, charge-discharge efficiency, self heat, and self-discharge of lithium-sulfur system on system shuttle constant, conduct the mechanism of these processes and simply analyse them.First to heat PVC and sulfur together at a certain temperature, where the melted sulfur being a fine dehydrogenating agent, captured hydrogen from PVC bone chain and led to an electrially conductive polymer with conjugated electrons. Remained sulfur, however, reacted with PVC almost in a melting state,...