A novel aluminium-Air rechargeable battery with Al2O3 as the buffer to suppress byproduct accumulation directly onto an aluminium anode and air cathode

An aluminium-air secondary battery was prepared with aluminium oxide placed adjacent to an aluminium anode and air cathode. Plain salt water was used as an electrolyte. The new structure of the aluminium-air battery exhibited a capacity that was almost constant when NaCl solution was refilled repeatedly, whereas the capacity of an aluminium-air battery with the general structure drastically deteriorates after the 1st cycle. It was found that aluminium oxide behaved as a buffer to suppress the accumulation of byproducts directly onto the electrodes. It was also suggested that aluminium ions conduct through the electrolytes which exist at the space between the aluminium oxide particles, and not through the bulk aluminium oxide.