Liu Kaige, Fan Yepeng, Ali Asad, Shen Pei Kang
Collaborative Innovation Center of Sustainable Energy Materials, Guangxi Key Laboratory of Electrochemical Energy Materials, School of Physical Science and Technology, Guangxi University, Nanning, 530004, PR China.
Nanoscale. 2021 Feb 7;13(5):2963-2971. doi: 10.1039/d0nr08712b. Epub 2021 Jan 28.
Lithium-sulfur (Li-S) batteries with high energy density, which show great application potential in flexible electronic products, have attracted a lot of research enthusiasm. However, the low utilization of sulfur and shuttle effect limit the application of Li-S batteries. Materials with a void structure and high conductivity can be used as a sulfur host to overcome these issues. Herein, a flexible MXene-coated textile fabric electrode (MF@TiCT/S) is designed by integrating the MXene-coated textile fabric (MF) with in situ sulfur loaded MXene nanosheets (TiCT/S). The MF provides a flexible 3D conductive framework, which is covered with TiCT/S nanosheets to form the layer-by-layer structure. This unique structure not only provides enough space for volume expansion to maintain the structural stability in the electrochemical process, but also promotes the physical encapsulation and chemical adsorption of lithium polysulfides (LiPSs). Consequently, the MF@TiCT/S50 electrode exhibits a high initial capacity of 916 mA h g at 1C and an ultralong-term cycling stability of 674 mA h g at 1C after 1000 cycles. Furthermore, this electrode also exhibits excellent rate performance at a high energy density (290 mA h g at 5C after 800 cycles). A pouch cell is prepared by using the MF@TiCT/S50 electrode and shows excellent cycle performances at different bending angles, which indicates that this study is valuable in the field of flexible energy storage. This work provides a new concept design for flexible Li-S batteries, which have great application potential as wearable and portable electronic devices.
具有高能量密度的锂硫(Li-S)电池在柔性电子产品中显示出巨大的应用潜力,吸引了众多研究热情。然而,硫的低利用率和穿梭效应限制了Li-S电池的应用。具有孔隙结构和高导电性的材料可作为硫宿主来克服这些问题。在此,通过将MXene包覆的织物(MF)与原位负载硫的MXene纳米片(TiCT/S)相结合,设计了一种柔性MXene包覆织物电极(MF@TiCT/S)。MF提供了一个柔性的三维导电框架,其表面覆盖有TiCT/S纳米片以形成层状结构。这种独特的结构不仅为体积膨胀提供了足够的空间,以在电化学过程中保持结构稳定性,还促进了多硫化锂(LiPSs)的物理封装和化学吸附。因此,MF@TiCT/S50电极在1C时表现出916 mA h g的高初始容量,在1000次循环后在1C时具有674 mA h g的超长循环稳定性。此外,该电极在高能量密度下(800次循环后在5C时为290 mA h g)也表现出优异的倍率性能。使用MF@TiCT/S50电极制备了软包电池,其在不同弯曲角度下均表现出优异的循环性能,这表明该研究在柔性能量存储领域具有重要价值。这项工作为柔性Li-S电池提供了一种新的概念设计,作为可穿戴和便携式电子设备具有巨大的应用潜力。