Comparison of nonaqueous electrolytes on oxygen reduction in Li-air batteries

The influence of nonaqueous electrolytes has been applied in the rechargeable Li-air battery. Discharged Li-air battery cathodes are investigated with palladium oxide (PdO) catalysts in four electrolytes which are different mixtures of lithium perchlorate, lithium hexaflourophosphate, ethylene carbonate, dimethyl carbonate, diethyl carbonate. Lithium palladium oxide (LiPdO) catalyst as cathode material is prepared by the sol-gel process by applying calcination at different times. The electrochemical performances of LiPdO catalysts in different electrolytes are determined by using electrochemical impedance spectroscopy, cyclic voltammetry and polarization techniques. LiPdO catalysts are characterized by X-ray and Scanning electron microscopy (SEM). In SEM images, it is observed that the structure of the LiPdO catalyst changed with calcination time. The results reveal that the LiPdO catalyst has excellent electrochemical performances when it is prepared at 500 °C for 10 h. Also according to the results, the LiPdO catalyst has the structural stability and shows great electrochemical performances in LCEDM (lithium perchlorate, ethylene carbonate, dimethyl carbonate) for the Li-air batteries.