Guiding bubble motion of rechargeable zinc-air battery with electromagnetic force

Rechargeable metal-air batteries will be a promising candidate for energy storage due to their high energy density. However, bubbles coalescence near the electrode blocks the following electrochemical reaction, seriously worsening the cycling performance of rechargeable zinc-air battery. Here we present control of oxygen bubbles movement with electromagnetic coupling, where a permanent magnet is placed near the electrode, and the strength of magnetic field at the electrode surface can be changed by means of spacing adjustment between the electrode and the magnet. The bubbles from oxygen evolution reaction can be quickly detached from the electrode surface under the condition of the electromagnetic field, achieving directional movement of oxygen bubbles. The results show that the electromagnetic field can inhibit bubbles coalescence, reducing phase transformation impedance and improving the performance of rechargeable zinc-air battery. The proposed solutions will be available for improving the morphology of metal electrodeposition as well as rechargeable metal-air batteries.