Results in Chemistry (Jan 2023)
Advancements in polyelectrolyte membrane designs for vanadium redox flow battery (VRFB)
Abstract
The polyelectrolyte membrane (PEM) is deputed as a pivotal component of vanadium redox flow battery (VRFB) devices and allows long-cycling life for practical applications. However, the bottlenecks in stability and high performance PEM designs has limited the utilization of this technology to laboratory wisdom. Herein, this review focuses on the critical topic of recent advancements in PEM designs and state-of-the art methodologies to acquire alternate stable membrane structures for its application in VRFB. The importance of these advanced membrane materials underlies determining the economic feasibility, safety and desire performance outputs. Moreover, there is a drastic shift in exploring the anion exchange polyelectrolyte materials over cation exchange polyelectrolyte material with performance equivalence of Nafion®. And this has elaborated a newer prospect in polymer synthesis and functionalization. Embarking towards advanced materials, a much comprehensive literature on recent structures and various designing strategies is critically required. This literature comprehensively and systematically summarises the basics of VRFB and developments of high performance membranes. In addition, we cover different fabrication strategies, ionic designs, composite material reinforced PEMs and alternate fluorinated backbone based PEMs attributed with better performance than Nafion®. Furthermore, degradation mechanisms and oxidative stability enhancing strategies is also included. The modification of microstructures in these materials is critical to acquire desired electrochemical properties and hence influence of variable functional architecture is briefly reviewed. The objective of this review is to summarise the recent membrane designs for efficient VRFB performances.
