Lithium−Air Battery: Promise and Challenges

TLDR

The lithium‑air battery, highlighted in 2009 as a potential electric‑vehicle power source rivaling gasoline energy density, relies on lithium oxidation at the anode and oxygen reduction at the cathode, but faces numerous scientific and technical challenges that must be overcome. This paper reviews the authors’ perspective on the promise and challenges of developing practical lithium‑air batteries and the current understanding of their chemistry. The authors summarize the electrochemical chemistry of lithium‑air batteries, noting that with aprotic electrolytes the lithium‑metal anode oxidation and air‑derived oxygen reduction can, in principle, be reversed by applying an external potential.

Abstract

The lithium−air system captured worldwide attention in 2009 as a possible battery for electric vehicle propulsion applications. If successfully developed, this battery could provide an energy source for electric vehicles rivaling that of gasoline in terms of usable energy density. However, there are numerous scientific and technical challenges that must be overcome if this alluring promise is to turn into reality. The fundamental battery chemistry during discharge is thought to be the electrochemical oxidation of lithium metal at the anode and reduction of oxygen from air at the cathode. With aprotic electrolytes, as used in Li-ion batteries, there is some evidence that the process can be reversed by applying an external potential, i.e., that such a battery can be electrically recharged. This paper summarizes the authors' view of the promise and challenges facing development of practical Li−air batteries and the current understanding of its chemistry. However, it must be appreciated that this perspective represents only a snapshot in a very rapidly evolving picture.