Comprehensive Analysis of Critical Issues in All-Vanadium Redox Flow Battery

Abstract

Vanadium redox flow batteries (VRFBs) can effectively solve the intermittent renewable energy issues and gradually become the most attractive candidate for large-scale stationary energy storage. However, their low energy density and high cost still bring challenges to the widespread use of VRFBs. For this reason, performance improvement and cost reduction of VRFBs are the keys to their commercialization and large-scale energy storage applications. On the basis of this, this perspective briefly describes the development status of renewable energy and energy storage technology and summarizes the existing bottlenecks that affect the development of VRFBs. Meanwhile, the critical technologies of VRFBs are reviewed, and the research progress in recent years and the challenges that need to be overcome are introduced. This perspective focuses on four aspects, including core component material, system modeling, optimization operations, and future business challenges. Then, a comprehensive analysis of critical issues and solutions for VRFB development are discussed, which can effectively guide battery performance optimization and innovation. The views in this perspective are expected to provide effective and extensive understanding of the current research and future development of vanadium redox flow batteries.

A Physical Organic Chemistry Approach to Developing Cyclopropenium-Based Energy Storage Materials for Redox Flow Batteries

“…The energy density is directly proportional to three properties of the anolyte/catholyte: (1) solubility in the electrolyte solution (which determines the overall concentration), (2) redox potential of the catholyte and anolyte (the difference between which dictates the cell voltage, V cell ), and (3) number of reversible redox events on each side of the cell (which determines the number of electrons transferred, n ). Commercial aqueous vanadium RFBs have concentrations of 1–1.5 M, V cell of ∼1 V, and n = 1, resulting in energy densities of ∼25 Wh/L. ,, …”

“…Commercial aqueous vanadium RFBs have concentrations of 1−1.5 M, V cell of ∼1 V, and n = 1, resulting in energy densities of ∼25 Wh/L. 8,9,20…”

“…Most commercial RFBs use aqueous solutions of vanadium salts as the anolyte and catholyte. , However, over the past decade there have been accelerating efforts to shift to redox active organic molecules (ROMs) as the energy storage materials. − ROMs have numerous desirable attributes for this application. First, they are composed of elements (carbon, hydrogen, nitrogen, oxygen) that are earth abundant and inexpensive.…”

The role of energy density for grid-scale batteries

“…With a plethora of available BESS technologies, including lithium-ion, sodium-sulfur and flow batteries, much attention has been dedicated to energy density as a key metric for economic and practical viability. [19][20][21][22][23][24][25][26][27] In principle, more energy-dense batteries allow more energy to be stored on a site with a given footprint, reducing costs and associated infrastructure needs. In fact, low energy density is frequently highlighted as the key limitation of flow batteries in academic literature and media reports, with the energy density on cell level typically being an order of magnitude lower than for lithium-ion batteries (LIB).…”

Study on the Self-Discharge of an All-Vanadium Redox Flow Battery through Monitoring Individual Cell Voltages

“…Flow battery modules still have problems such as low power density and low energy density. Huang et al 9 reviewed the current development status of renewable energy and energy storage technologies. The report also summarized the research progress and challenges in the development of VRFB.…”