Two‐Membrane Acid‐Base Flow Battery with Hydrogen Electrodes for Neutralization‐to‐Electrical Energy Conversion. Issue 20 (20th September 2021)

• Record Type: Journal Article
• Authors: Loktionov, Pavel; Bocharova, Anastasia; Konev, Dmitry; Modestov, Alexander; Pichugov, Roman; Petrov, Mikhail; Antipov, Anatoliy
• Is Part Of: ChemSusChem. Volume 14:Issue 20(2021)
• Page Start: 4583
• Page End: 4592
• Publication Date: 2021-09-20
• Subjects: electrochemistry -- energy conversion -- flow battery -- hydrogen -- neutralization; Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.202101460
• Languages: English
• ISSNs: 1864-5631

Abstract

Abstract: Acid‐base flow batteries (ABFB) are a promising and environmentally benign class of flow batteries that utilize neutralization energy. Among the other flow batteries, ABFBs stand out with low cost and high solubility of the electrolytes and the possibility to harvest neutralization energy of acidic and alkaline wastewaters. However, the main ABFB issues, such as low power caused by discharge current limitation and low energy density, are limiting the possibility of their implementation. In this work, a novel two‐membrane ABFB with two hydrogen electrodes was developed to overcome main ABFB issues. The proposed concept demonstrated high power density up to 6.1 mW cm −2 at 13 mA cm −2 . It was shown that battery performance was greatly limited by negative electrode overvoltage. Analysis of the voltage losses allowed to estimate main power losses and highlight the possible ways to its minimization. Abstract : Two for one : A novel two‐membrane acid–base flow battery with hydrogen electrodes is proposed. The battery demonstrates high power density up to 6.1 mW cm −2 at 13 mA cm −2 . In the galvanostatic discharge at 4 mA cm −2, the maximum energy efficiency is 53.9 % at 58.1 % electrolyte utilization. Measurements of electrode potential during cell polarization demonstrate that the main factor limiting power is the negative hydrogen electrode contacting with alkali.