The Research On Discharge Performance Of Square Lithium-air Batteries

Lithium air batteries have recently received wide attention due to their extremely high theoretical energy densities.Although the lithium air battery is a very attractive system, there are still many challenges that need to be overcome before practical applications. Our research focused on cathode blockage by discharge products.Galvanostatic discharge, EIS, BETand SEM were employed for investigation. The battery was discharged to 2.0V at 0.1m A/cm2 for 1370 h at 25℃ and relative humidity of 30%. It was found that the Li air battery ends its discharge due to increase of charge transfer impedance caused by expansion of Air electrode.The effect of carbon loading and binder content on the discharge performance of lithiumair battery was investigated. The urea was used as pore former, Produced a dual porosity of the air electrode, and the discharge performance of the battery increased by 32 %.Perovskite catalyst samples La Ni0.5Co0.5O3 was successfully prepared By sol-gel method. Initial discharge time of the KB-LNCO air electrode was 1131 h at a current density of 0.1m A/cm2, and the battery showed good discharge performance at a high current density.Li PF6 electrolyte salt with PC/EC, TEGDME and DMSO were investigated on the influence of discharge charge performance of lithiumair batteries. Initial discharge time of the PC/EC, TEGDME and DMSO was 821 h, 840 h and 1076 h respectively. It demonstrated that DMSO as solvent delivered the best electrochemical performance. DMSO electrolyte with lithium salts including Li PF6, Li As F6, Li TFSI and Li Cl O4 were also investigated. It was found that discharge time of four different lithium salt electrolyte solute in prepared with lithium air batteries was similar. Last, modification of PE separator Using P(VDF+HFP), reducing the charge transfer changes in the internal impedance of the battery over time, to extend the discharge time.