Thin and thick metal hydride (MH) electrodes used in air–MH batteries were evaluated with respect to electrochemical performances. The influence of electrode thickness on the discharge capacity, rate capability, charge and discharge voltages was investigated as well as the effect of MH packing density within electrodes on the electrode performances was also examined. The mass transport within the porous electrode was found to be the rate limiting step with increasing electrode thickness. The power output could be increased by either using thin electrodes or decreasing electrode density. This was, however, done at the expense of the energy density of the cell.