Electrochemical analysis of electrolyte temperature and composition for all-iron redox flow battery

ABSTRACT

At present, aqueous all-iron flow batteries have become one of the most potentials flow batteries system due to their low cost and environmental-friendly operation. However, the battery performance and cycle-life will to a great extent be limited by the electrolytes, which are mainly influenced by temperature, electrolyte concentration, and electrolyte additives. Herein, we repeatedly conducted the electrochemical tests on catholyte and anolyte in varied temperatures and electrolyte concentrations. Based on the analyses, it is proved that the electrolyte of an all-iron flow battery is suitable for high-temperature conditions. By comparing the electrochemical performance of anolyte and anolyte with citrate, the citrate is proved to be an effective additive in solving the problem of anolyte reversibility. This work can guide the conditional design of all-iron flow battery energy storage devices, and meanwhile, the solution is proposed to enhance the anolyte reversibility of the all-iron flow battery.

KEYWORDS:

• All-iron flow battery
• electrochemical analysis
• electrolyte
• electrolyte additive
• reversibility

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Natural Science Foundation of Liaoning Province [Grant No. 2020-MS-012], the National Natural Science Foundation of China [Grant No. 21805290] and the Institute of Metal Research, Chinese Academy of Sciences.