Ionic liquid-modified poly(propylene carbonate)-based electrolyte for all-solid-state lithium battery

Due to their high safety and excellent thermal stability, all-solid-state lithium batteries have been explored widely in the recent years, which are highly in demand for future energy storage. Herein, we propose a novel type of all-solid-state electrolyte, which is prepared by the modification of ionic liquid with poly(propylene carbonate) (PPC)-based polymer electrolyte. The selected ionic liquid, 1-vinylimidazole bis(trifluoromethanesulfonyl)imide (VIm-TFSI), acts as a plasticizer to be integrated into the PPC matrix. Such a VIm-TFSI-modified PPC-based electrolyte (PPC-25IL) has an ionic conductivity of 8.2 × 10−5 S cm−1 at room temperature. Moreover, it enables a highly reversible Li plating/stripping for Li anode, resulting in a dramatically improved rate and cyclic performance of LiFePO4-Li all-solid-state batteries. The VIm-TFSI plasticizer not only increases the ionic conductivity of PPC-based electrolyte but also improves the interfacial comparability of PPC-based electrolyte with the electrode. This work proposes a new strategy to develop all-solid-state lithium battery for real applications.