Recent advances and prospects of K-ion conducting polymer electrolytes

Potassium resources are at the top of the list of options, not only due to their availability but also due to their comparable physical and chemical similarities to lithium. In order to fabricate the K-ion-conducting electro-chemical devices, the development of electrolytes is as important as that of the electrodes. The key challenges in developing K-ion conducting electrolytes include the extreme side reactions at the electrolyte and potassium metal, the unstable electrolyte/electrode interface, and poor coulombic efficiency. Polymer electrolytes possess the same ion-transport characteristics as liquid electrolytes. This review examines the recent advances and pro-spects of K-ions conducting polymer electrolytes. This review highlights the key challenges of solid polymer electrolytes, viz. conventional solid polymer electrolytes, blended polymer electrolytes, and nanocomposite polymer electrolytes. A comprehensive discussion on using carbonate, glymes, and ionic liquid-based K-ion conducting electrolytes is also provided. The timeline development and possible applications of the K-ion con-ducting electrolytes is discussed. The future directions for exploring the hidden potential of K-ion conducting polymer gel electrolytes for electrochemical systems are summarized.