Balancing high energy density and chemical stability in redox flow batteries with symmetric tetrazines

27 December 2021, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Nonaqueous redox flow batteries are a promising technology for grid-scale energy storage, however, their commercial success relies on identifying redox active materials that exhibit extreme potentials, high solubilities in all states of charge, and long cycling stabilities. Meeting these requirements has been particularly challenging for molecules capable of storing negative charge. Within this context, the symmetric tetrazines remain unexplored despite their unique structural properties that enable them to meet these challenges. Herein, we prepared s-tetrazines substituted with methyl, methoxy, and thiomethyl substituents and evaluated their electrochemical properties, solubility, and cycling stability. These studies revealed that 3,6-dimethoxy-s-tetrazine undergoes a reversible one-electron reduction to generate a soluble (>0.5 M in electrolyte/solvent) and stable (t1/2 > 1240 h) radical anion. When implemented in a lab-scale flow battery, it exhibited a relatively slow capacity fade of 13% over 100 cycles (38 h). Given their uncommonly high solubility and cycling stability, we believe that s-tetrazine derivatives should be further explored for non-aqueous redox flow batteries.


redox flow batteries

Supplementary materials

Supporting Information File
Contains experimental details, and data/results referenced in the MS.


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.