Abstract
Progress in renewable energy production has directed interest in advanced developments of energy storage systems. The all-vanadium redox flow battery (VRFB) is one of the attractive technologies for large scale energy storage due to its design versatility and scalability, longevity, good round-trip efficiencies, stable capacity and safety. Despite these advantages, the deployment of the vanadium battery has been limited due to vanadium and cell material costs, as well as supply issues. Improving stack power density can lower the cost per kW power output and therefore, intensive research and development is currently ongoing to improve cell performance by increasing electrode activity, reducing cell resistance, improving membrane selectivity and ionic conductivity, etc. In order to evaluate the cell performance arising from this intensive R&D, numerous physical, electrochemical and chemical techniques are employed, which are mostly carried out ex situ, particularly on cell characterizations. However, this approach is unable to provide in-depth insights into the changes within the cell during operation. Therefore, in situ diagnostic tools have been developed to acquire information relating to the design, operating parameters and cell materials during VRFB operation. This paper reviews in situ diagnostic tools used to realize an in-depth insight into the VRFBs. A systematic review of the previous research in the field is presented with the advantages and limitations of each technique being discussed, along with the recommendations to guide researchers to identify the most appropriate technique for specific investigations.
Highlights
The rapid development of industries for more than two centuries has heavily relied on the exploitation of fossil fuels
The findings suggested that local current distribution reflects the combined effect of the local concentration of electrolyte and electrolyte velocity
This study showed that the interdigitated open channel and interdigitated circular poked channel reduced the pressure drop with a uniform flow of electrolytes [129]
Summary
The rapid development of industries for more than two centuries has heavily relied on the exploitation of fossil fuels. The direction of the net electrolyte transfer depends on the type of membrane used in the stack (negative to positive half-cell for cation and opposite direction for anion exchange). Carbon felts are chemically inert and can withstand the highly corrosive positive half-cell electrolyte They are electrically conductive to transport current to the bipolar plate [9,16]. The ion exchange membrane divides two half-cells containing the negative and the positive electrolyte by allowing only charge transport to keep electrical neutrality. Numerous studies have been performed for vanadium redox flow batteries (VRFBs) on electrode pre-treatment, electrolyte stability, membrane and cell design to improve the overall cell performance.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
