Stabilizing lithium metal using ionic liquids for long-lived batteries.
Suppressing dendrite formation at lithium metal anodes during cycling is critical for the implementation of future lithium metal-based battery technology. Here we report that it can be achieved via the facile process of immersing the electrodes in ionic liquid electrolytes for a period of time before battery assembly. This creates a durable and lithium ion-permeable solid-electrolyte interphase that allows safe charge-discharge cycling of commercially applicable Li|electrolyte|LiFePO4 batteries for 1,000 cycles with Coulombic efficiencies >99.5%. The tailored solid-electrolyte interphase is prepared using a variety of electrolytes based on the N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide room temperature ionic liquid containing lithium salts. The formation is both time- and lithium salt-dependant, showing dynamic morphology changes, which when optimized prevent dendrite formation and consumption of electrolyte during cycling. This work illustrates that a simple, effective and industrially applicable lithium metal pretreatment process results in a commercially viable cycle life for a lithium metal battery.
School of Applied Sciences, Applied Chemistry, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia.|Energy Flagship, Commonwealth Scientific and Industrial Research Organisation, Clayton, Melbourne, Victoria 3169, Australia.
A
A
Basile
Energy Flagship, Commonwealth Scientific and Industrial Research Organisation, Clayton, Melbourne, Victoria 3169, Australia.
A I
AI
Bhatt
School of Applied Sciences, Applied Chemistry, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia.|School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Queensland 4001, Australia.
A P
AP
O'Mullane