LAUSR

Acid-base flow batteries (ABFB) are promising and environmentally benign class of flow batteries that utilize neutralization energy. Among the other flow batteries, ABFBs outstand 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, we report a novel two-membrane ABFB with two hydrogen electrodes to overcome main ABFB issues. Proposed concept demonstrates high power density up to 6.1 mW cm -2 at 13 mA cm -2 . It is shown that battery performance is greatly limited by negative electrode overvoltage. Analysis of the voltage losses allows us to estimate main power losses and highlight the possible ways to its minimization.