Moss-like Growth of Metal Electrodes: On the Role of Competing Faradaic Reactions and Fast Charging

Uncontrolled crystal growth during electroreduction of reactive metals in liquid electrolytes produces mossy metal deposits. Here, we use electroanalytical rotating disk electrode (RDE) studies to elucidate the origin moss-like electrodeposition metals. Competing Faradaic reactions on surface are shown be source phenomenon. A regime can accessed by subtle shifts electrolyte chemistry and deposition rate. For Zn─a that conventionally is not known form electrodeposits─obvious patterns emerge at low-current densities strongly alkaline electrolytes. Conversely, under conditions where rate large relative competing reactions, Zn eliminated. The same principle holds for Li deposition. On basis, an empirical rule proposed─an applied current density i satisfies relation 10 < 0.8 ilim required achieving favorable electrodeposit morphology fast charging batteries.