Electrochemical Performance Analysis Of Porous Cathode Structures And Bifunctional Cathode Catalysts For Lithium Air Batteries

With the phenomenon of environmental pollution and non-renewable energy shortage is increasing,the development of a new environmentally friendly sustainable energy is imperative.Lithium-air batteries have been widely concerned around the world because of their high theoretical energy.However,many problems about achieving the commercialization of Lithium-air batteries are as following:the electrolyte solvent is easily volatile,easy to break the electrolyte charge,lithium metal is easily corroded,lithium dendrite growth and the cathode gap is blockaged.These problems are the hot spots of lithium air battery research,then how to effectively protect the lithium anode and improve the catalytic performance of the cathode catalyst is the key to improve the performance of lithium air batteries.This paper presents a double gas channel porous anode structure of the lithium air battery,which can form a dynamic balance of gas doping in the internal of the battery,effectively inhibit the oxygen into the anode penetration,thus protecting the lithium anode.The anodic corrosion is confirmed by electron scanning microscopy and Raman spectroscopy analysis of the anode chips after the discharge.Accoring to analysising the cyclic voltammetry,AC impedance,constant current charge and discharge and power energy characteristics,this new type of lithium-ion battery has a great performance,the first discharge capacity can reach 2910 mAh g^-1,the specific energy of 7200 Wh kg^-1,cycle life can attain 38 times.In this paper,the cathode catalyst for lithium air battery is also studied.A nanometer material catalyst MnO/Mn₃O₄ was prepared by vacuum DC arc method.The new materials are characterized by XRD,SEM and BET,the results shows that this material has lattice defects and vacancies,which greatly improves the electronic conductivity and catalytic activity of the materials,and the particle size and pore size are suitable for the lithium air battery.The electrochemical properties of the composites are analyzed by cyclic voltammetry,AC impedance,constant current charge and discharge.It is found that this catalyst has a good performance in oxygen oxidation and oxygen reduction,because it can greatly improve the battery cycle life,and with the capacity limit of 0.100 mA cm-2 current density 1000 mAh g^-1,it can work for 29 cycles.