Study On The Performance And Preparation Process Of Air Battery With Metal Oxide Catalyst

As a clean energy, air battery has the advantages of high energy density, long storage time and environmental friendliness. When the battery works, the active metal, the anode of the air cell, does not produce any pollutions and the cathode has infinite theory of energy because they only consumes the oxygen in the air, which makes them widely used in the future. However, the oxygen reduction performance of the air electrode restrictes the output power of the air battery, so how to improve the oxygen reduction performance of air electrode has become the focus of research.In this paper, two aspects of catalyst preparation and air electrode process optimization has been explored to improve the oxygen reduction performance of air electrode.The perovskite type oxides (LaCoO3, LaMnO3, La0.95Sr0.05MnO3 and LaFeO3) and spinel type oxides (CoFe2-xMnxO4 (x=0.1,0.3,0.5)) were prepared by sol gel method. The XRD and SEM analysis showed that the products are all pure-phased.When the voltage is-0.4V, the polarization current density of LaCoO3 is 376mAcm-2, which is higher than that of LaMnO3 and LaFeO3. when add trace amounts of Sr into LaMnO3, the polarization current density were increased. After 5% Mn doped CoFe2O4, the polarization current density were rised from 311mAcm"2 to 365mAcm"2, increased by 17%; However, with the increase of Mn content, the polarization current density is decreased, which probably affected by the crystal lattice distortion.Through the experiment, the optimum ratio of gas diffusion layer and catalyst layer of air electrode was finally determined. That is, PTFE accounts for 30% of the total mass of the gas diffusion layer; the mass ratio of catalyst LaMnO3, active carbon and acetylene black in the catalyst layer was 3:4:1. And when PTFE accounted for 30% of the total mass, the oxygen reduction performance of the air electrode was the highest. When the voltage is-0.4V, the polarization current density of the air electrode is 369mAcm"2, which is higher than that of the general air electrode polarization current density, increased by 200%, and air electrode can work stably above 35h in this conditions.