Recent Advances in the Application of Magnetite (FeO) in Lithium-Ion Batteries: Synthesis, Electrochemical Performance, and Characterization Techniques.

With the promotion of portable energy storage devices and the popularization of electric vehicles, lithium-ion battery (LiB) technology plays a crucial role in modern energy storage systems. Over the past decade, the demands for LiBs have centered around high energy density and long cycle life. These parameters are often determined by the characteristics of the active materials in the electrodes. Given its high abundance, environmental friendliness, low cost and high capacity, magnetite (FeO) emerges as a promising anode material. However, the practical application of FeO faces challenges, such as significant volume expansion during cycling. To overcome these obstacles and facilitate the commercialization of FeO, a comprehensive understanding of its properties and behavior is essential. This review provides an overview of recent FeO research advances, focusing on its synthesis, factors influencing its electrochemical performance, and characterization techniques. By thoroughly understanding the characteristics of FeO in LiB applications, we can optimize its properties and enhance its performance, thereby paving the way for its widespread use in energy storage applications. Additionally, the review concludes with perspectives on promoting the commercialization of FeO in LiBs and future research directions.