Al‐Air Batteries

Aluminum–air (Al–air) batteries have received tremendous attention due to the high energy density, light weight, low cost, and abundant reserve of Al anodes. This chapter presents the fundamentals and recent progress of primary Al–air batteries, and the newly emerged rechargeable Al–air batteries are also introduced. Firstly, the electrochemical reactions and electrode materials in Al–air batteries are presented. Then, the challenges and the associated solutions are discussed. The anode issue of Al–air batteries is the low anode utilization efficiency caused by self-corrosion, and various strategies are proposed. The cathode issue of Al–air batteries is to explore low-cost and high-performance electrocatalysts to replace Pt-based noble metals, and transition metal-based, carbon-based, and single atoms electrocatalysts are reported for oxygen reduction reactions. Furthermore, various electrolytes and structure design of Al–air batteries are supplemented for comprehensive understanding. We hope this chapter can help readers to understand the fundamentals and current research progress of Al–air batteries.