Emerging Battery Systems with Metal as Active Cathode Material

The high‐cost and limited availability of raw materials for lithium‐ion batteries hinder their future development and urge researchers to explore alternative battery systems. Among them, batteries utilizing the electrochemical redox reaction of metals such as Cu, Fe, Sn, etc. as the cathode to reversibly store and release energy are attractive because their raw materials are common and abundant. This review examines this type of novel battery system, introduces its basic mechanism and problems, analyses the strategies that are used to improve its reversibility and cycling stability and also proposes some possible future directions of investigations. Metal‐cathode battery is a novel battery system where low‐cost, abundant metals with high electrode potential can be used as the positive electrode material. Recent progresses with emphases on the cathode, anode, electrolyte, and separator of the batteries are summarized and future research directions are proposed in this review paper.