Performance and Perspectives of an Acid/Base Flow Battery

Abstract

Recently, the utilisation of renewable energy sources is a matter of increasing importance in Europe for Energy Transition and to achieve energy independence. To this aim, tailored Electric Energy Storage (EES) devices must be employed to tackle the issue of fluctuating production from renewables. The Acid/Base Flow Battery (AB-FB) is a cutting-edge technology that allows energy to be stored in the form of acidic and alkaline solutions (van Egmond et al., 2018). This method employs two membrane processes, one for the charge phase and one for the discharge phase, namely Electrodialysis with Bipolar Membrane (EDBM) and Reverse Electrodialysis with Bipolar Membrane (REDBM), respectively. The polymeric membranes and the two electrodes are the main components of this battery. The AB-FB is a novel technology, and a lot of effort is needed to properly assess its current and future potential and identify the geometrical and operating conditions maximising its performance. This study presents a techno-economic analysis (TEA) carried out by using technically optimal results from a previous bi-objective optimisation (Culcasi, et al., 2022b). By assessing the sensitivity on the input parameters, the Levelized Cost of Storage (LCOS) of a battery operating in closed-loop and using current commercial membranes spanned from 0.17 € kWh−1 to 0.45 € kWh−1, indicating that the AB-FB has significant potential in the commercial market.