context: Electrolyte additives may modify lithium deposition in several different ways, e.g. by influencing initial SEI formation on the current collector, the nucleation stage of lithium metal deposition, the growth of lithium metal deposits, or some combination thereof. To investigate during which step of lithium metal electrodeposition HF plays an active role, a cell was first galvanostatically brought down to 0 V vs. the counter electrode (CE, Li/Li+) at 0.5 mA cm−2 in LP30 containing 100 ppm added HF to form the initial SEI on copper (Fig. 3a). The electrolyte was then removed, the cell rinsed with as-received LP30, and refilled with as-received LP30 for deposition of lithium metal (Fig. 3b). There is no voltage plateau ∼2 V indicative of HF reduction, but we observe an additional small amount of capacity below 1 V which is consistent with solvent reduction. Lithium metal with a highly monodispersed columnar morphology (Fig. 3c) was still deposited although there was no HF in the electrolyte during electroplating. This demonstrates that it is the initial SEI on copper which directs the microstructure and that HF does not play an active role beyond the initial SEI formation. This experimental evidence is in agreement with studies in the literature that report the formation of a columnar microstructure without additives when a LiF rich layer was deposited ex situ on copper prior to cell assembly.