Simulation of species transport in metal air battery

Abstract

In this study, the Li-air battery has investigated which has exceptionally high specific energy due to the high specific energy of lithium and the inexhaustible oxygen supply of the ambient air. Although, the high specific capacity of lithium-air battery, but, there formation of binary lithium oxide (Li2O2) which presents irreversible deposit inside cathode porous media. A one-dimensional model was developed to study the various properties of Li air batteries. Mainly, the discharge current, the effects of electrode thickness and the distribution of the porosity in the electrode are examined. Advanced studies on transport phenomena have not yet fully exploited the great potential of Li-Air batteries. This is mainly the result of limiting the mass transfer of the cathode electrode. The resistivity of the deposit layer provided by reaction products has great effects on the discharge characteristics of Li-air batteries. In this matter the investigation shows an important voltage drop according to specific capacity. The analysis of discharge curves shows that cathode porosity has an important effect on specific capacity of battery. But, the reaction rate has more influence on battery voltage. The diffusion of oxygen plays an important role in to drive the reactant inside the cathode. This characteristic encourages the chemical reaction which contributes to improve the battery performance. Finally, for future works, we recommend for deep studies and detailed analysis, to overcome the problem of Li2O2 deposit in order to improve the battery performances.