Sul Hyunki, He Jiarui, Manthiram Arumugam
Walker Department of Mechanical Engineering The University of Texas at Austin Austin TX 78712 USA.
Small Sci. 2023 Aug 22;3(10):2300088. doi: 10.1002/smsc.202300088. eCollection 2023 Oct.
Enhancing the reversibility of Li is crucial for extending the cycle life of Li-limited anode-free lithium-sulfur (Li-S) batteries. Incorporating tellurium (Te) in the system has proven to be highly effective by its reaction with polysulfides and forming a passivating interfacial layer on Li surface, which reduces the Li-ion diffusion barrier. However, due to the poor utilization of Te, a significant amount of Te is required to improve cell cycling performance. To address this, nanowire-structured Te (TeNW) is synthesized via a hydrothermal method and applied to LiS-based anode-free cells to minimize the Te content in the system while extending the cell cycle life. Coating TeNW onto the separator greatly enhances Te utilization and demonstrates a significant cycle life improvement (38% retention over 300 cycles) with only 4 wt% TeNW content relative to the active material. The versatility of TeNW is further demonstrated by utilizing them with carbon nanotubes as the anode substrate. The exceptional performance of TeNW is attributed to the high-surface-area nanostructure and excellent conductive network, facilitating efficient electron transfer during cell cycling. These advantageous properties position TeNW as a promising material to enhance the cycle life of Li-limited Li-S batteries.
提高锂的可逆性对于延长锂限量无负极锂硫（Li-S）电池的循环寿命至关重要。在该体系中引入碲（Te）已被证明是非常有效的，因为它能与多硫化物反应并在锂表面形成钝化界面层，从而降低锂离子扩散势垒。然而，由于碲的利用率较低，需要大量的碲来改善电池的循环性能。为了解决这个问题，通过水热法合成了纳米线结构的碲（TeNW），并将其应用于基于硫化锂的无负极电池中，以在延长电池循环寿命的同时尽量减少体系中的碲含量。将TeNW涂覆在隔膜上可大大提高碲的利用率，并且相对于活性材料仅含有4 wt%的TeNW含量时，电池循环寿命有显著提高（300次循环后保留率为38%）。通过将TeNW与碳纳米管一起用作阳极基底，进一步证明了TeNW的多功能性。TeNW的优异性能归因于其高表面积纳米结构和优异的导电网络，有助于电池循环过程中的高效电子转移。这些有利特性使TeNW成为一种有前途的材料，可用于延长锂限量Li-S电池的循环寿命。
