Recent Progress and Perspective in Electrode Materials for K‐Ion Batteries

The development of rechargeable batteries using K ions as charge carriers has recently attracted considerable attention in the search for cost‐effective and large‐scale energy storage systems. In light of this trend, various materials for positive and negative electrodes are proposed and evaluated for application in K‐ion batteries. Here, a comprehensive review of ongoing materials research on nonaqueous K‐ion batteries is offered. Information on the status of new materials discovery and insights to help understand the K‐storage mechanisms are provided. In addition, strategies to enhance the electrochemical properties of K‐ion batteries and computational approaches to better understand their thermodynamic properties are included. Finally, K‐ion batteries are compared to competing Li and Na systems and pragmatic opportunities and future research directions are discussed. K‐ion batteries are attracting much attention as an emerging energy storage system for large‐scale applications. This review article provides the most up‐to‐date information on recent progress in the K‐technology focusing on important negative and positive electrode materials. This article also discusses the science behind their electrochemistry and K storage mechanism.