Zhao Yun, Huang Limin, Zhao Dan, Yang Lee Jim
Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117585, Singapore, Singapore.
Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Avenue, 518055, Shenzhen, P. R. China.
Angew Chem Int Ed Engl. 2023 Sep 4;62(36):e202308976. doi: 10.1002/anie.202308976. Epub 2023 Jul 28.
The two major issues confronting the commercialization of rechargeable lithium-sulfur (Li-S) batteries are the sluggish kinetics of the sulfur electrochemical reactions on the cathode and inadequate lithium deposition/stripping reversibility on the anode. They are commonly mitigated with additives designed specifically for the anode and the cathode individually. Here, we report the use of a single cathode modifier, In Se , which can effectively catalyse the polysulfide reactions on the cathode, and also improve the reversibility of Li deposition and removal on the anode through a LiInS /LiInSe containing solid electrolyte interface formed in situ by the Se and In ions dissolved in the electrolyte. The amounts of dissolved Se and In are small relative to the amount of In Se administered. The benefits of using this single modification approach were verified in Li-metal anode-free Li-S batteries with a Li S loading of 4 mg cm and a low electrolyte/Li S ratio of 7.5 μL mg . The resulting battery showed 60 % capacity retention after 160 cycles at the 0.2 C rate and an average Coulombic efficiency of 98.27 %, comparing very well with recent studies using separate electrode modifiers.
可充电锂硫（Li-S）电池商业化面临的两个主要问题是阴极上硫电化学反应的动力学缓慢以及阳极上锂沉积/剥离的可逆性不足。通常分别使用专门为阳极和阴极设计的添加剂来缓解这些问题。在此，我们报告了使用单一阴极改性剂InSe，它可以有效催化阴极上的多硫化物反应，还能通过溶解在电解质中的Se和In离子原位形成的含LiInS/LiInSe固体电解质界面来提高阳极上锂沉积和去除的可逆性。相对于所添加的InSe的量，溶解的Se和In的量较少。在锂硫负载量为4 mg cm且电解质/锂硫比例低至7.5 μL mg的无锂金属阳极锂硫电池中验证了使用这种单一改性方法的益处。所得电池在0.2 C倍率下经过160次循环后容量保持率为60%，平均库仑效率为98.27%，与最近使用单独电极改性剂的研究相比表现出色。
