Lithium–air batteries possess a high theoretical energy density and are considered promising candidates for next-generation power sources for electric vehicles. However, one of the major challenges for practical application is the improvement of power performance. In particular, the low solubility and diffusivity of oxygen in the electrolyte limit oxygen transport to the cathode reaction surface, thereby causing a reduction in output during discharge. In this study, a low-dimensionalzed cathode was employed to mimic the oxygen transport phenomena in porous electrodes. This setup enabled discharge experiments to clarify the effect of oxygen transport on the spatial distribution of the discharge reaction. Previous study used structures where oxygen from the atmosphere was easily transported to the reaction surface; however, the present configuration allows discharge experiments that better represent oxygen transport through the pore of the porous cathode. The experimental results were compared with the analytical results obtained from a transmission line model to examine the distributions of oxygen concentration and discharge reaction. These findings will contribute to future considerations in designing cathode structures aimed at improving power output.
Sasaki et al. (Wed,) studied this question.