Entrapment of sulfur in hierarchical porous graphene for lithium-sulfur batteries with high rate performance from-40 to 60 °C
Entrapment of sulfur in hierarchical porous graphene for lithium-sulfur batteries with high rate performance from-40 to 60 °C
复制标题
DOI：
10.1016/j.nanoen.2012.10.003
复制
发表时间：
2013-03-01
期刊：
影响因子：
17.6
通讯作者：
Wei, Fei
中科院分区：
文献类型：
--
作者：
Huang, Jia-Qi;Liu, Xiao-Fei;Wei, Fei
Li-S电池具有比常规锂离子电池大得多的理论能量密度。实现高性能Li-S电池电极的关键在于将构建块排列成精心设计的结构，其中纳米碳框架不仅充当封装的活性材料的电子导管，而且还充当微型电化学反应室。因此，提出并制备了一种用于锂硫电池的纳米复合材料，其中硫被捕获到分级多孔石墨烯中。在0.5和10 C的电流密度下，纳米复合电极的放电容量分别为1068和543 mA·h·g（-1）。在-40摄氏度的超低温下可呈现386 mA h g（-1）的放电容量，远远超过了传统锂离子电池的工作范围。大规模制备的分级结构石墨烯主要被环氧基和羟基修饰，由于官能团的诱导作用，可以增强S与C-C键的结合。这些结果为具有高电容的能量存储装置提供了有前途的电极材料，这对于寒冷环境中日益增长的电源需求（例如用于寒冷地区电动车辆或航空应用的电池系统）是重要的。(C)2012爱思唯尔有限公司保留所有权利。
The Li-S battery is with a much greater theoretical energy density than those of conventional lithium ion batteries. The key to achieve a high performance electrode for Li-S battery lies in the arrangement of the building blocks into a well-designed structure, in which the nanocarbon framework not only acts as an electronic conduit to the encapsulated active materials but also serves as a mini-electrochemical reaction chamber. Therefore, a nanocomposite with sulfur entrapped into hierarchical porous graphene was proposed and fabricated for Li-S batteries. The nanocomposite electrode exhibits high discharging capacitance of 1068 and 543 mA h g(-1) at a current density of 0.5 and 10 C, respectively. The discharging capacity of 386 mA h g(-1) can be presented at ultra-low temperature of -40 degrees C, which far exceeds the operating range of conventional lithium-ion batteries. The large scale produced hierarchal graphene was mainly decorated with epoxy and hydroxyl groups, which can enhance the binding of S to the C-C bonds due to the induced ripples by the functional groups. These results provided a promising electrode material for energy storage device with high capacitance, which is important for the increasing demands of power sources in cold environments, such as battery systems for electric vehicles in cold zone or for aeronautic applications. (C) 2012 Elsevier Ltd. All rights reserved.