Peng Sikan, Yan Shaojiu, Wang Nan, Nan Wenzheng, Wang Jixian, Chen Xiang, Wang Chen, Qi Xin, Dai Shenglong
Beijing Institute of Aeronautical Materials (BIAM) Beijing 100095 P. R. China
RSC Adv. 2018 Apr 3;8(23):12701-12707. doi: 10.1039/c8ra00226f.
It is a great challenge to obtain high performance carbon fluoride (CF ) cathodes with high specific capacity and good rate performance due to the electronic conductivity of CF being known to decrease with an increase in the specific capacity. Herein, we propose a novel fluorinated graphene (FG)/sulfur hybrid cathode to enhance both the energy density and power density of lithium/carbon fluoride (Li/CF ) batteries. Impressive enhancements of the specific capacity, discharge voltage, and rate capability are demonstrated with the novel FG/sulfur hybrid cathode. In comparison with the pristine FG cathode, the hybrid cathode exhibits higher electrochemical activity, lower overpotential, and faster ion transfer over the main discharge range. Furthermore, when the melt-diffusion method is used to prepare the hybrid cathode, the uncommon monoclinic sulfur is presented under ambient temperature. A significant synergistic effect which reduces the reaction resistance effectively is demonstrated with the presence of monoclinic sulfur, leading to the highest energy density of 2341 W h kg and a power density up to 13 621 W kg at 8.0 A g. Our results are expected to introduce a new generation of high energy and high power density lithium primary cells, based on a simple and effective strategy employing FG/S hybrid cathodes.
由于已知氟化碳（CF ）的电子电导率会随着比容量的增加而降低，因此获得具有高比容量和良好倍率性能的高性能氟化碳（CF ）阴极是一项巨大的挑战。在此，我们提出了一种新型的氟化石墨烯（FG）/硫混合阴极，以提高锂/氟化碳（Li/CF ）电池的能量密度和功率密度。新型FG/硫混合阴极在比容量、放电电压和倍率性能方面都有显著提升。与原始FG阴极相比，混合阴极在主要放电范围内表现出更高的电化学活性、更低的过电位和更快的离子转移。此外，当采用熔体扩散法制备混合阴极时，在室温下会出现罕见的单斜硫。单斜硫的存在证明了一种显著的协同效应，有效地降低了反应电阻，在8.0 A g时导致最高能量密度为2341 W h kg，功率密度高达13621 W kg。我们的结果有望基于一种使用FG/S混合阴极的简单有效策略，引入新一代高能量和高功率密度的锂原电池。
