Abstract: State-of-the-art flow batteries suffer from drawbacks such as congestion of their electrodes, defects in liquid tightness, or shunt currents, all of which may lead to efficiency drop. Solution The problem is solved by a flow battery comprising multi-chambered ducts (100) mutually plugged together, each duct containing an integrated air electrode (111) and partition walls being partly ion-permeably perforated and partly impermeable, and nonconducting joining elements with integrated passages, the joining elements plugged bilaterally onto the ducts (100).