Electrochemical Energy Laboratory, Materials Science and Engineering Program, The University of Texas at Austin, Austin, Texas 78712, USA.
Nat Commun. 2012;3:1166. doi: 10.1038/ncomms2163.
The limitations in the cathode capacity compared with that of the anode have been an impediment to advance the lithium-ion battery technology. The lithium-sulphur system is appealing in this regard, as sulphur exhibits an order of magnitude higher capacity than the currently used cathodes. However, low active material utilization and poor cycle life hinder the practicality of lithium-sulphur batteries. Here we report a simple adjustment to the traditional lithium-sulphur battery configuration to achieve high capacity with a long cycle life and rapid charge rate. With a bifunctional microporous carbon paper between the cathode and separator, we observe a significant improvement not only in the active material utilization but also in capacity retention, without involving complex synthesis or surface modification. The insertion of a microporous carbon interlayer decreases the internal charge transfer resistance and localizes the soluble polysulphide species, facilitating a commercially feasible means of fabricating the lithium-sulphur batteries.
与阳极相比，阴极的容量有限一直是锂离子电池技术发展的障碍。在这方面，硫体系很有吸引力，因为硫的容量比目前使用的阴极高出一个数量级。然而，低的活性材料利用率和较差的循环寿命阻碍了锂硫电池的实际应用。在这里，我们报告了对传统锂硫电池结构的简单调整，以实现高容量、长循环寿命和快速充电速率。在阴极和隔膜之间使用双功能微孔碳纸，我们不仅观察到活性材料利用率的显著提高，而且还观察到容量保持率的提高，而无需涉及复杂的合成或表面改性。微孔碳中间层的插入降低了内部电荷转移电阻并局部化了可溶性多硫化物物种，为制造锂硫电池提供了一种可行的商业方法。
