![]() ![]() Another approach to overcome this challenge of limited supply of O 2 is presented by Nichols et al., who reported about an improved cathode utilization by increasing the partial pressure of O 2 within the battery. One possibility to increase the concentration of dissolved O 2 within the electrolyte is to utilize perfluorinated additives. ![]() Our findings on the pulse discharging can be transferred to other metal-oxygen battery systems and might assist in achieving their full potential regarding practical energy density. Interestingly, we show for the first time that the superoxide is deposited in a very unusual form of stacked and highly oriented crystal layers. The higher amount of dissolved oxygen accumulated during the resting period after a current pulse is essential to form more of the discharge product, i.e., the metal oxide sodium superoxide. By implication, the pulse discharging mode ensures better supply with dissolved oxygen within the cathode. We optimize the chosen resting-to-pulse times, the applied current density, and elucidate that three-dimensional cathode materials yield higher capacities compared to two-dimensional ones. In this work, we achieve better cathode utilization and higher discharge capacities by using pulse discharging. However, the promised values for energy density and capacity are not met in practical studies yet due to poor utilization of the void space in the cathode during battery discharge. Using sodium metal in sodium-oxygen batteries with aprotic electrolyte enables achieving a very high theoretical energy density. ![]()
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