Abstract
Neutral zinc-iron flow batteries (ZIFBs) remain attractive due to features of low cost, abundant reserves, and mild operating medium. However, the ZIFBs based on Fe(CN)63-/Fe(CN)64- catholyte suffer from Zn2Fe(CN)6 precipitation due to the Zn2+ crossover from the anolyte. Even worse, the opposite charge properties of positive and negative active species enable a big contradiction in the design of a suitable membrane. Herein, sodium citrate (Cit) was introduced to coordinate with Zn2+, which effectively alleviated the crossover and precipitation issues. Meanwhile, the redox species exhibited considerable kinetics and reversibility with a good capability of hydrogen evolution inhibition. As a result, the assembled battery demonstrated a high energy efficiency of 89.5% at 40 mA cm-2 and operated for 400 cycles with an average Coulombic efficiency of 99.8%. Even at 100 mA cm-2, the battery showed an energy efficiency of over 80%. This paper provides a possible solution toward a low-cost and sustainable grid energy storage.
| Original language | English |
|---|---|
| Pages (from-to) | 3426-3432 |
| Number of pages | 7 |
| Journal | ACS Energy Letters |
| Volume | 9 |
| Issue number | 7 |
| Early online date | 24 Jun 2024 |
| DOIs | |
| Publication status | Published - 12 Jul 2024 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2024 American Chemical Society.
Funding
This work was financially supported by the National Natural Science Foundation of China (Grant No. 22209179), International collaborative project of CAS (121421KYSB20210028), and Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA21070100 and XDB17020000).
