Stable High-Temperature Lithium-Metal Batteries Enabled by Strong Multiple Ion-Dipole Interactions.

Abstract

Lithium-metal batteries (LMBs) capable of operating stably at high temperature application scenarios are highly desirable. Conventional lithium-ion batteries could only work stably under 60 °C because of the thermal instability of electrolyte at elevated temperature. Here we design and develop a thermal stable electrolyte based on stable solvation structure using multiple ion-dipole interactions. The strong coordination in solvated structure of electrolyte defines the Li deposition behaviour and the evolution of solid electrolyte interphase at high temperature, which is important to achieve high Li Coulombic efficiency and avoid Li dendritic growth. For high mass loading LiFePO4 -Li cells, the cells at 60 °C with conventional electrolyte easily run into failures, but the cells with our electrolyte at 90 °C and 100 °C could cycle more than 120 and 50 cycles respectively. This work provides new insight into electrolyte design and contributes to the development of high temperature LMBs.