Liquid Phase Scanning Electron Microscopy: A New Approach to Investigate Lithium Dendrite Formation in Liquid Electrolytes

Abstract

Scanning electron microscopy (SEM) is a widely used tool for investigating the surface morphology of materials with a reasonable spatial resolution. Comparing with the high-resolution transmission electron microscopy (TEM), the beam-induced damage is much less in a SEM. With a proper scan rate, some relatively slow dynamic process, such as the lithium dendrite growth, can be observed in real time using a SEM. To mimic the real environment of a lithium battery, we designed a micro-liquid-electrochemical cell in which organic electrolytes could be introduced. We investigated the lithium deposition and dissolution processes in such a cell using electrolytes with different additives, and studied their effects on suppressing dendrite growth during lithium deposition. The results should shed light on developing more stable batteries using lithium metal as the anode material.