Materials and Electrochemistry of Metal-Air Battery

Abstract

To explore clean and sustainable energy storage systems with high energy density, metal-air batteries have recently gained great interest. Metal-air batteries have turned out to be promising candidates for next-generation rechargeable batteries due to their high energy densities compared to commercial Li-ion batteries, lead acid batteries, and nickel-metal hydride batteries. Since there is much progress noted in the field of metal-air batteries over the past decade, however, its practical application is still under investigation due to several issues such as unstable anode in atmospheric moisture, large polarization, and slow kinetics. It was found that the design of electrode materials and regulation of catalytic oxygen reduction of metal-air batteries must be scrutinized for large-scale device application. Metal-air batteries are a group of electrochemical cells that produce electricity via oxidation of metal and reduction of atmospheric oxygen. Several types of metal-air batteries are under discussion, which is typically based on metal species (e.g., Zn, Li, Mg, Al, etc.) and electrolyte (aqueous or non-aqueous). Since the electrode reactions of metal-air batteries vary as per their metal anode and electrolyte, Li-air batteries (non-aqueous) and Zn-air batteries (aqueous) are two types of metal-air batteries that have attracted much attention due to their high energy density and cell potential. Therefore, this chapter will cover the fundamentals of the electrochemistry involved in aqueous and non-aqueous metal-air batteries.