Development status, challenges, and perspectives of key components and systems of all-vanadium redox flow batteries

All-vanadium redox flow batteries (VRFBs) have experienced rapid development and entered the commercialization stage in recent years due to the characteristics of intrinsically safe, ultralong cycling life, and long-duration energy storage. However, VRFBs still face cost challenges, making it necessary to comprehensively optimize the performance and reduce the manufacturing costs of each component. The review first introduces the development history of VRFBs and emphasizes their huge market demand. Second, the bottlenecks existing in key components (electrodes, bipolar plates, membranes, and electrolytes) and battery management systems of VRFBs are summarized, and the corresponding latest improvement examples are proposed. Last, the review points out the future development direction of key components and systems of VRFBs. The review discusses the latest technology routes for reducing the cost and optimizing the performance of VRFBs, which are needed for accelerating applications and penetrations in large-scale and long-duration energy storage. • Development history and market demand of VRFBs are summarized. • Key component bottlenecks of VRFBs and corresponding solution routes are summarized. • Cost challenges and future development directions of VRFBs are summarized.