Center for Energy Convergence Research, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 136-791, South Korea.
Nanoscale Res Lett. 2013 Aug 3;8(1):343. doi: 10.1186/1556-276X-8-343.
The intrinsic low conductivity of sulfur which leads to a low performance at a high current rate is one of the most limiting factors for the commercialization of lithium-sulfur battery. Here, we present an easy and convenient method to synthesize a mono-dispersed hollow carbon sphere with a thin graphitic wall which can be utilized as a support with a good electrical conductivity for the preparation of sulfur/carbon nano-composite cathode. The hollow carbon sphere was prepared from the pyrolysis of the homogenous mixture of the mono-dispersed spherical silica and Fe-phthalocyanine powder in elevated temperature. The composite cathode was manufactured by infiltrating sulfur melt into the inner side of the graphitic wall. The electrochemical cycling shows a capacity of 425 mAh g-1 at 3 C current rate which is more than five times larger than that for the sulfur/carbon black nano-composite prepared by simple ball milling.
硫的本征低电导率导致其在高电流速率下性能较低，这是阻碍锂硫电池商业化的最主要因素之一。在这里，我们提出了一种简便的方法，可合成具有薄石墨层的单分散空心碳球，将其用作具有良好导电性的载体，用于制备硫/碳纳米复合材料正极。空心碳球是通过均分散的球形二氧化硅和铁酞菁粉末在高温下的均匀混合物的热解制备的。复合正极是通过将硫熔体渗透到石墨层的内侧来制造的。电化学循环显示，在 3C 电流速率下的容量为 425mAh g-1，是通过简单的球磨制备的硫/炭黑纳米复合材料的五倍以上。
