Materials challenges and technical approaches for realizing inexpensive and robust iron–air batteries for large-scale energy storage

A high performance iron–air rechargeable battery has the potential of meeting the requirements of grid-scale energy storage. When successfully demonstrated, this battery technology can be transformational because of the extremely low cost of iron, the extraordinary environmental friendliness of iron and air, and the abundance of raw materials. The key technical challenges that hinder the successful commercialization of the iron–air battery are its efficiency and cycle life. An innovative multi-pronged strategy that aims at raising the round-trip energy efficiency from 50% to 80%, and the cycle life from 2000 to 5000 cycles is therefore necessary to meet the requirements of large scale energy storage.