A boron-based electrolyte additive for calcium electrodeposition

Abstract In recent years, several organic electrolytes have been reported allowing calcium metal electrodeposition. In all cases, some degree of passivation on the surface of the calcium electrode was reported. Following a recent report on borate-based passivation layer playing a crucial role for Ca plating in electrolyte solutions containing Ca(BF4)2, here we report the use of a boron-containing additive. The presence of this additive allows Ca plating and stripping using a Ca(TFSI)2 containing electrolyte, which otherwise lead to the formation of a fully Ca2+ blocking passivation layer.