In-situ polymerized separator enables propylene carbonate electrolyte compatible with high-performance lithium batteries

Abstract

Propylene carbonate (PC) is a solvent of liquid electrolytes for lithium-based batteries. It has attracted considerable research attention, due to its high dielectric constant, high solubility for lithium salts, and wide liquid range. Lithium metal (Li) anodes do not have a graphitic intercalation structure, which prevents PC from forming a stable protective solid electrolyte interphase (SEI) and leads to catastrophic exfoliation; therefore, Li anodes are expected to use PC as the only solvent. However, batteries with the Li anodes are limited by low operating lifespans, because of the lithium dendrite and parasitic reaction between the electrolyte and Li electrode. Here, we report that by utilizing a uniform in-situ polymerized nanoporous separator, the lithium dendrite can be significantly suppressed. A Li-symmetric cell offers steady cycling for 1400 h. Moreover, a full LiCoO2│Li battery shows a good cycling performance even in a LiPF6/PC electrolyte both at room temperature and 60 °C. This work highlights the potential for the large-scale application of PC electrolytes in lithium batteries.