A Co-Axial Microtubular Flow Battery with Ultra-High Volumetric Power

Abstract

The increasing application of renewable energy sources has created the need for efficient electric energystorage. Redox flow batteries offer a viable alternative for these applications, having the advantages of long-life cycles and decoupling the power output and the storage capacity. Current RFBs use a planarconfiguration for the reactor. This configuration has been thoroughly studied and it has probably reached itsupper limit with respect to power density. This work presents a scalable hollow-fiber based co-axialmicrotubular flow battery design which proves to be a major leap forward in the power density of RFBs. Thisengineering solution provides significantly higher packing efficiency and membrane surface-to-area-ratio,lowering the capital cost and improving the volumetric power density. The performance of the new device isassessed by measuring the peak charge and discharge power densities, as well as the cycling performancefor both organic and inorganic redox couples.