Synthesis and Characteristics of Nanoporous Carbon Spheres/S Composite as Cathode Material for Li-S Battery

In this paper, three kinds of activated carbon microspheres with different particle size were prepared by hydrothermal method and carbon dioxide activation method by adjusting the concentration of sucrose solution (0.15M, 0.3M and 1.5M, respectively). Three kinds of composite materials, S-AMCS-0.15, SAMCS-0.3 and S-AMCS-1.5, were prepared by the real air phase method, and the corresponding sulfur contents were 52%, 46% and 42%, respectively. The structure and morphology of various materials were characterized. The electrochemical properties of the three composites were investigated and compared. The experimental results show that S-AMCS-0.15 has good electrochemical performance. Due to the small particle size of AMCS-0.15 carbon microspheres, the active materials inside the spheres can be fully reacted. In order to further optimize the electrochemical properties of the composite, the material was treated by ball milling. The results show that the capacity retention and cycling properties of the composite have been improved to a certain extent. The discharge specific capacity in the second week also increased from 720 mAh g(-1) to more than 1180 mAh g(-1). And the discharge capacity maintained above 800 mAh g(-1) for the first 60 cycles.