No abstract

Lithium–air battery (LAB) technology is currently being considered as a future technology for resolving energy and environmental issues. Here, we introduce recent advances and the remaining technical challenges in the development of LABs, particularly focusing on the cathodes based on a fundamental understanding of Li–O2electrochemistry.

Rechargeable metal-air batteries have attracted a great interest in recent years because of their high energy density. The critical challenges facing these technologies include the sluggish kinetics of the oxygen reduction-evolution reactions on a cathode (air electrode). Here, we report doped lanthanum nickelates (La2NiO4) with a layered perovskite structure that serve as efficient bifunctional electrocatalysts for oxygen reduction and evolution in an aqueous alkaline electrolyte. Rechargeable lithium-air and zinc-air batteries assembled with these catalysts exhibit remarkably reduced discharge-charge voltage gaps (improved round-trip efficiency) as well as high stability during cycling.

To realize all-solid-state lithium batteries, it is necessary to develop solid electrolytes with high ionic conductivity and stability. A total Li+ conductivity as high as 4.8 × 10−4 S cm−1 can be achieved for perovskite Li3xLa(2/3)−x□(1/3)−2xTiO3 at 25 °C via microstructural modifications.