Energetic and dynamic principles of potassium electrodeposition in potassium metal batteries

Abstract

Potassium metal batteries offer a sustainable and cost-effective solution for high-energy storage applications. However, uncontrolled potassium dendrite growth remains a major obstacle to achieving long-term stability. In this review, we provide a holistic overview by establishing a theoretical framework for potassium nucleation and early-stage growth, identifying key factors that influence stable electrodeposition. We discuss representative materials and substrate design strategies that address these factors and emphasize the importance of several energetic parameters, including contact angle, surface energy, interfacial energy, binding energy, and combined binding/interfacial energies. These descriptors offer insight into the thermodynamic and kinetic processes governing potassium deposition. In addition, we explore the dynamic role of the solid-electrolyte interphase, particularly its mechanical properties and ionic conductivity, which critically impact deposition behavior. Finally, we outline future research directions toward a principle-driven, knowledge-based approach for regulating potassium electrodeposition, aiming to lay the groundwork for the practical development of next-generation potassium metal batteries.