High-energy-density lithium-sulfur (Li-S) batteries are among the most promising energy storage devices, but their potential has been constrained by the shuttle effect and poor active material utilization. Here, 3,3′-dithiodipropionic acid (DTPA), an efficient electrolyte additive, is applied to Li-S batteries while its underlying mechanism on the electrochemical performance is examined. The results show that the DTPA additive can quickly interact with the polysulfides scattered in the electrolyte, facilitating the conversion of long-chain polysulfides to Li₂S₂ and Li₂S. In this way, by lessening the shuttle effect of long-chain polysulfides towards the anode, the redox kinetics and the usage of active materials can both be improved. The electrochemical performance of Li-S batteries is thus enhanced by the addition of DTPA, with capacities of 1093.4 mA · h/g for the initial cycle and 714.8 mA · h/g after 250 cycles at 0.5C (DTPA concentration is 1.5 wt.%). Also, the DTPA-containing batteries have higher electrochemical stability, with a capacity retention rate of 57.5% relative to 0.1 C at 2C. The improved performance demonstrates the importance of electrolyte additives, and the DTPA introduced in this work offers a potential solution for reducing the shuttle effect of polysulfide to increase the capacity of Li-S batteries.

高能量密度锂硫（Li-S）电池是最有前途的储能装置之一，但其潜力受到穿梭效应和活性材料利用率差的限制。这里，3,3'-二硫代二丙酸（DTPA）是一种高效的电解液添加剂，被应用于锂硫电池，同时研究了其电化学性能的潜在机制。结果表明，DTPA添加剂能够快速与分散在电解液中的多硫化物相互作用，促进长链多硫化物转化为Li ₂ S ₂和Li ₂ S，从而通过减弱长链多硫化物的穿梭效应对于阳极，氧化还原动力学和活性材料的使用都可以得到改善。因此，添加DTPA增强了Li-S电池的电化学性能，初始循环容量为1093.4 mA·h/g，0.5 C下循环250次后容量为714.8 mA·h/g（DTPA浓度为1.5 wt.% ）。 %）。此外，含有DTPA的电池具有更高的电化学稳定性，在2C时相对于0.1C的容量保持率为57.5% 。性能的提高证明了电解质添加剂的重要性，这项工作中引入的DTPA为减少多硫化物的穿梭效应以提高Li-S电池的容量提供了潜在的解决方案。