Quantification of Electrode Pulverization Enabled through Operando Video Microscopy of an Electrodeposited Antimony Anode

Alloying anodes, such as metallic antimony, demonstrate promise as alternative electrode materials for lithium-ion battery systems due to their high theoretical capacity of 660 mA h g–1. However, antimony undergoes anisotropic volume expansion and multiple crystallographic phase transformations upon lithiation and delithiation, which often lead to fracturing or pulverization of the electrode. This pulverization can result in the loss of electrical contact and poor cycling stability. To better understand the degradation mechanism of these electrodes, we demonstrate the use of operando video optical microscopy in tandem with electrochemical testing and a program for the quantification of pulverization for the development of failure mechanism hypotheses. This method is broadly applicable to the characterization and understanding of electrochemically induced mechanical failure mechanisms in high energy density electrodes.