Bao Hongfei, Dong Yujiao, Wu Xuesong, Li Guangfu, Zhu Fulong, Guan Wei, Wang Xinlong, Su Zhongmin
National & Local United Engineering Laboratory for Power Battery, Key Laboratory of Polyoxometalate Science, Institute of Functional Material Chemistry, Northeast Normal University, Changchun, Jilin 130024, China.
Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry, School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022, China.
ACS Appl Mater Interfaces. 2020 Aug 12;12(32):36220-36227. doi: 10.1021/acsami.0c10811. Epub 2020 Aug 3.
The lithium-sulfur battery is a promising high-energy-density storage system, which suffers from severe capacity fading due to the "shuttle effect" and low Coulombic efficiency caused by the dissolution of lithium polysulfides. At the molecular level, suppressing the shuttle effect has been greatly required for high-performance Li-S batteries. Herein, we propose a new strategy by utilizing a protonated organic absorbent (,-bis(pyridine-3-ylmethyl)butane-1,4-diammonium nitrate ([HPBD]·(NO)) for ultrafast absorption of polysulfides through electrostatic attractions and for fixing the polysulfides in the cathode by hydrogen-bond interactions. A lithium-sulfur battery cathode based on a commercial carbon black (CB) and an absorbent (10%) with high sulfur content (70%) exhibits a low capacity decay of 0.099% per cycle over 400 cycles at a rate of 0.5C along with 91% Coulombic efficiency. This strategy and the finding of an electrostatic absorbent offer a new alternative insight into designing cheaper lithium-sulfur batteries for their practical application in the future.
锂硫电池是一种很有前景的高能量密度存储系统，由于“穿梭效应”导致严重的容量衰减，以及多硫化锂溶解导致库仑效率低。在分子水平上，高性能锂硫电池非常需要抑制穿梭效应。在此，我们提出一种新策略，利用质子化有机吸收剂（1,4-双（吡啶-3-基甲基）丁烷-1,4-二铵硝酸盐（[HPBD]·(NO₃)₂））通过静电吸引超快吸收多硫化物，并通过氢键相互作用将多硫化物固定在阴极中。基于商业炭黑（CB）和高硫含量（70%）吸收剂（10%）的锂硫电池阴极在0.5C倍率下400次循环中每循环容量衰减低至0.099%，同时库仑效率为91%。该策略以及静电吸收剂的发现为未来设计更便宜的锂硫电池以实现其实际应用提供了新的见解。
