A Base Case Design and Capital Cost Analysis of an All Vanadium Redox-Flow Battery

Interest in the development of redox-flow batteries (RFBs) for large-scale grid storage is growing, and considerable investments have been made into the research and development of RFBs over the past few decades. Unfortunately, practical implementation has been hampered by various cost and performance issues typical of an immature state of development. One critical factor for the competitiveness of this technology is the installed cost. The purpose of this work is to develop an evolutionary procedure to be used for the base-case design of a Vanadium Redox-Flow Battery, and to incorporate recent developments in all-vanadium RFB research in order to present an analysis of the associated cost factors. The design methodology is based on the work of Douglas (1985) and provides a profitability analysis at each decision level so that more profitable alternatives and directions can be indentified before additional time and effort is expended on an impractical design. The major components of a RFB that affect installed cost are also identified and used as variables to create a capital cost function. The function is then used to calculate the rate of change of the capital costs with respect to the major components. The capital costs are also calculated for a range of component values and presented. Key findings include a high sensitivity of system capital cost to purity of vanadium and substantial fractions of the cost associated with perflurorosulfonic acid membranes currently used for proton transport. The key factors that contribute to the capital cost trends of different VRB designs are also examined, leading to a simple method for selecting key design variables before beginning the design process itself.