Abstract
To date, dilute ether electrolytes have been believed to be incompatible with graphite in Li-ion batteries due to the detrimental solvent cointercalation and graphite exfoliation. Here, we provide design criteria of dilute ether electrolytes for a reversible graphite anode based on tailoring the solvation structures and thermodynamic properties. We clarify that ether solvents can support graphite reversibly by modulating the anion. Our redesigned electrolyte consisting of a single-solvent 1,3-dioxolane (DOL) and 1 M single-salt lithium bis(fluorosulfonyl)imide (LiFSI) shows weakened Li-solvent interaction and results in an inorganic-rich solid-electrolyte interphase. Consequently, we achieved ∼99.9% Coulombic efficiency with >96% capacity retention (∼350 mAh/g) after 300 cycles at C/5 using natural graphite. The weakly solvated electrolyte maintains desirable transport properties, enabling better rate capability than carbonate electrolytes with an areal capacity of 2-4 mAh/cm2. We have demonstrated the potential of dilute ether electrolytes for facile desolvation-based intercalation chemistry in graphite, creating a viable path toward fast-charge Li batteries.
| Original language | English |
|---|---|
| Pages (from-to) | 1379-1389 |
| Number of pages | 11 |
| Journal | ACS Energy Letters |
| Volume | 8 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 10 2023 |
Funding
The work was supported by Institute for Critical Technology and Applied Science at Virginia Tech and the Sun Grant program of the National Institute of Food and Agriculture (NIFA), USDA, USA. E.P.K. and L.C. were supported by the Joint Center for Energy Storage Research (JCESR), a U.S. Department of Energy, Energy Innovation Hub. The use of the Stanford Synchrotron Radiation Light Source, SLAC National Accelerator Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under contract no. DE-AC02-76SF00515. This research used the electron microscopy resources of the Center for Functional Nanomaterials (CFN), which is a U.S. Department of Energy Office of Science User Facility, at Brookhaven National Laboratory under contract no. DE-SC0012704. We gratefully acknowledge the computing resources provided on Bebop, a high-performance computing cluster, operated by the Laboratory Computing Resource Center at Argonne National Laboratory. We thank Yijie Yin and Prof. Shirley Meng at UC San Diego for the Raman data collection. We thank Dr. Haodong Liu and Prof. Ping Liu at UC San Diego for providing LiFSI. We appreciate the help of Claudio Amaya Santos (Virginia Tech) in assisting the ATR-FTIR data collection.