Journal:Nature Energy, 2021, 6, 517-528

Key Words:Polysulfide is one of the most promising aqueous redox chemistries for grid storage owing to its inherent safety, high energy and low cost. However, its poor cycle life resulting from polysulfide cross-over has prohibited its successful commercialization. To exploit low-cost and high-capacity polysulfide flow batteries with industrial-relevant cycling stability, we develop a charge-reinforced ion-selective membrane to retain polysulfide/iodide, restrain membrane swelling and prevent water/OH− migration. The polysulfide/polyiodide static cell demonstrates a low capacity decay rate (0.005% per day and 0.0004% per cycle) over 2.9 months (1,200 cycles) at a 100% state of charge. A flow cell containing 4.0 M KI/2.0 M K2S2 demonstrated stable cycling at 17.9 Ah l−1 posolyte+negolyte over 3.1 months (500 cycles). Small-angle X-ray scattering and in-situ attenuated total reflectance–Fourier transform infrared/solid-state NMR revealed reduced water cluster size and restrained water movement in the charge-reinforced ion-selective membrane compared to commercial Nafion membrane. Techno-economic analysis shows that the developed polysulfide flow battery promises competitive levelized cost of storage for long-duration energy storage.

Note:This paper is highlighted as the cover for Nature Energy

Co-author:Zhejun Li

Indexed by:Journal paper

Correspondence Author:Yi-Chun Lu*

Document Code:https://doi.org/10.1038/s41560-021-00804-x

Volume:6

Page Number:517-528

Translation or Not:no

Date of Publication:2021-09-25