Perspective of operando/in situ scanning electron microscope in rechargeable batteries

With an ever-increasing demand for clean energy, rechargeable batteries have undergone significant development, owing to their high energy density, power density, safety, and affordability. It is crucial to employ qualitative and quantitative techniques that can operate under real battery working conditions. These techniques enable the determination of the dynamic evolution of the microstructure, phase composition, chemical composition, and local chemical environment of the battery interior and interface. Operando/in situ scanning electron microscopy (SEM) has emerged as a valuable tool in rechargeable battery research, benefited from its high temporo-spatial resolution and comprehensive analysis capabilities facilitated by multiple detectors. It has found widespread application in understanding the fundamental mechanisms and real-time tracking of reaction dynamics in rechargeable batteries. This concise review focuses specifically on operando/in situ SEM with various configurations for investigating interfacial phenomena in rechargeable batteries. Furthermore, notable future opportunities and developments have been discussed.