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DOE OSTI · 2574074

Synchronized Breathing in Anion-Derived Interphases

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 Li 2 O, the role of amorphous inorganic species and the interplay between the anode-electrolyte interphase (SEI) and the cathode-electrolyte interphase (CEI) remain largely unexplored. Here, 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.

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Tan, Sha [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:000000018277893X), Xia, Kangxuan [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Wang, Nan [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000224500689), Yen, Dean [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Yu, Zhiao [Stanford Univ., CA (United States)] (ORCID:0000000187461640), Rahman, Muhammad Mominur [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Chen, Xiaobo [Univ. of Pittsburgh, PA (United States)], Chen, Yuelang [Stanford Univ., CA (United States)] (ORCID:0000000252490596), Yang, Xiao-Qing [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000236253478), Xiao, Jie [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000255205439), Liu, Jun [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000186637771), Cui, Yi [Stanford Univ., CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)] (ORCID:0000000261036352), Bao, Zhenan [Stanford Univ., CA (United States)] (ORCID:0000000209721715), Hu, Enyuan [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000218814534). 2025-07-12. Synchronized Breathing in Anion-Derived Interphases. https://doi.org/10.1021/acsenergylett.5c01756

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