Study On Prepartion And Performance Of Catalysts And Cathode Structure In Metal Air Battery

Metal air battery is a semi fuel battery with the characteristics of primary battery and fuel cell,it has the advantages of high specific energy,low cost,stable discharge voltage and so on.As an energy conversion device(energy storage device),the anode is mostly active metal,and the main reactant of the cathode reaction is oxygen without pollution,the theoretical energy tends to infinity,which has important research value.I studyed both air cathode catalyst preparation and air electrode preparation process optimization two aspects,in order to further improve the performance of metal-air batteries.In this paper,the spinel structure of CoFe2O4 was prepared by sol-gel method.Through the optimization of the process parameters,the suitable preparation conditions were determined to obtain the nano-sized powder material,and based on this,the effects of doping elements and doping amount on the structure,morphology and electrochemical properties of the materials were investigated.The results show that the polarization current density of CoFe1.9Mn0.1O4 can reach 376mA/cm2 when the polarization potential is—0.6V.In addition,NiCo2O4 and MnCo2O4 with different morphologies were also prepared in this paper.The results showed that the performance of nano-particle catalyst is better than that of nano-spherical catalyst in air electrode.Secondly,the preparation of air electrode was optimized in this paper.The optimum conditions for the catalyst,activated carbon,acetylene black and polytetraflu-oroethylene(PTFE)in the cathode catalyst layer were investigated by orthogonal experiment L16(34)Ratio.The experimental results showed that when the mass ratio is 3:4:1 and PTFE is 30%of the total mass,the oxygen reduction performance of the air electrode is the highest.Polarization potential of-0.6V,the polarization current dens-ity of 369 mA/cm2,the prepared air battery can work more than 35 h stablely;In addition,This paper also discussed the influence of the amount of catalyst layer coating and the direct electrodeposition method for the preparation of air electrode catalyst,and draw some useful conclusions.