Research progress of alkaline earth metal iron-based oxides as anodes for lithium-ion batteries

Anode materials are an essential part of lithium-ion batteries (LIBs), which determine the performance and safety of LIBs. Currently, graphite, as the anode material of commercial LIBs, is limited by its low theoretical capacity of 372 mA·h·g⁻¹, thus hindering further development toward high-capacity and large-scale applications. Alkaline earth metal iron-based oxides are considered a promising candidate to replace graphite because of their low preparation cost, good thermal stability, superior stability, and high electrochemical performance. Nonetheless, many issues and challenges remain to be addressed. Herein, we systematically summarize the research progress of alkaline earth metal iron-based oxides as LIB anodes. Meanwhile, the material and structural properties, synthesis methods, electrochemical reaction mechanisms, and improvement strategies are introduced. Finally, existing challenges and future research directions are discussed to accelerate their practical application in commercial LIBs.