The invention is a redox flow battery (1000) comprising n electrochemical cells 300 that are electrically connected in series (300) with each cell including a cathode (310) and an anode (320) that are separated by a membrane (330) and that are respectively passed through by a catholyte and an anolyte originating from a catholyte tank (110) and an anolyte tank (120). The cells are fluidically connected in parallel. The invention is also a system for decreasing bi-pass currents including means (700) for injecting a gas into the inlet ducts (401) and outlet ducts (501) of the cathode and anode of (n−1) cells to form gas bubbles; and a device (800) for removing the gas bubbles, placed, on the inlet ducts of the cathode and anode of the (n−1) cells, downstream of the means for injecting the gas and upstream of the cathode and anode of the cells.