Abstract
Anion-derived interphases are crucial for extending the cycle life of lithium metal batteries. While their benefits are often attributed to crystalline inorganic species like LiF and Li2O, the role of amorphous inorganic species and the interplay between the anode-electrolyte interphase (SEI) and the cathode-electrolyte interphase (CEI) remain largely unexplored. In this study, we examine two model electrolyte systems─one with solvent-derived interphases and the other with anion-derived interphases─using advanced X-ray scattering and spectroscopy techniques. Our findings reveal that anion-derived interphases contain substantial amounts of amorphous inorganic species, leading to a unique synchronization of “breathing” between SEI and CEI. During charging, the SEI grows while the CEI shrinks; during discharging, these roles reverse. This distinctive interfacial behavior originates from the competition of deposition and dissolution of amorphous inorganics during cycling. The study highlights the unique role of amorphous inorganics in anion-derived interphases, providing new insights into improving battery performance and durability.
| Original language | English |
|---|---|
| Pages (from-to) | 3746-3754 |
| Number of pages | 9 |
| Journal | ACS Energy Letters |
| Volume | 10 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 8 2025 |
| Externally published | Yes |
Funding
The work done at Brookhaven National Laboratory was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the US Department of Energy (DOE) through the Advanced Battery Materials Research (BMR) Program, including Battery500 Consortium under contract no. DE-SC0012704. This research used beamlines 28-ID-2, 23-ID-2, 8-BM and 7-ID-2 (managed by the National Institute of Standards and Technology) of the National Synchrotron Light Source II, a US DOE Office of Science user facility operated for the DOE Office of Science by Brookhaven National Laboratory under contract no. DE-SC0012704. TEM and EDS measurements used the resources of the Center for Functional Nanomaterials, a US DOE Office of Science User Facility at BNL, under contract no. DE-SC0012704. The cathode electrodes were provided by Cell Analysis, Modeling, and Prototyping (CAMP) Facility at Argonne National Laboratory. The CAMP Facility is fully supported by the DOE Vehicle Technologies Office.