Abstract:

As the increasing demands of energy storage devices, high energy density rechargeable batteries have been strongly considered. Thanks to the low mass density, high theoretical specific energy density, and lowest redox potential, metallic lithium becomes one of the most promising anode materials to build high-performance rechargeable batteries. However, the formation of lithium dendrites causes rapid capacity degradation, short cycle life, and potential safety hazard of working lithium batteries. This hinders its practical applications. In-situ observation is highly beneficial to explore the growth mechanism of lithium dendrites and improve the battery performance. In this review, the progress on in-situ observation devices, their applications in Li dendrite observation and the obtained models for dendrite growth are summarized. Finally, the perspective of lithium metal anode through in-situ/operando characterization is discussed.

Key words:  lithium metal anode, lithium dendrites, growth mechanism, in-situ characterization, optical microscope, electron microscopy