Fig. 1: Electrolyte design principles for lean electrolyte LMBs with minimal Li corrosion.
From: Borate–pyran lean electrolyte-based Li-metal batteries with minimal Li corrosion
a, A scheme of electrolyte design strategy of the borate–pyran electrolyte. The conventional carbonate electrolyte exhibits dendritic Li morphology and Li corrosiveness, leading to the depletion of both Li and the electrolyte with a rapid drop in cell capacity. Recently developed Li-compatible electrolytes (for example, LHCE) exhibit a uniform Li morphology but still suffer from electrolyte depletion due to persistent Li corrosiveness showing sudden capacity drop. In contrast, the borate–pyran electrolyte not only maintains a uniform Li morphology but also limits Li corrosion by a restructured SEI, mitigating the depletion of Li and the electrolyte and enabling extended cycle life. b, A chemical process of SEI restructuring in the borate–pyran electrolyte. The reaction of BF3-THP formation from THP and BF4 and its reverse reaction (that is, dissolution of LiF by the BF3-THP) restructures LiF-containing SEI on Li with the borate–pyran electrolyte.
