Designing Advanced Electrolytes for High-Voltage High-Capacity Disordered Rocksalt Cathodes

Ahmed, Ridwan A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000329186219); Mohanakrishnan, Rohith Srinivaas [University of California, Berkeley, CA (United States)]; Wang, Jingyang [University of California, Berkeley, CA (United States)]; Koirala, Krishna P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:000000029137917X); Zhao, Qian [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Environmental Molecular Sciences Laboratory (EMSL)] (ORCID:0000000344893691); Fu, Yanbao [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017752680X); Chen, Ying [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)]; Rastinejad, Justin C. [University of California, Berkeley, CA (United States)]; Li, Tianyu [University of California, Berkeley, CA (United States)]; Zhong, Lirong [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:000000015052939X); Zuba, Mateusz [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000232097922); Siu, Carrie [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000225035408); Kahvecioglu, Ozgenur [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000239883301); Clément, Raphaële J. [Univ. of California, Santa Barbara, CA (United States)]; McCloskey, Bryan D. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000165992336); Battaglia, Vincent S. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000255969148); Persson, Kristin [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000324955509); Wang, Chongmin [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Environmental Molecular Sciences Laboratory (EMSL)] (ORCID:0000000333270958); Xu, Wu [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000226858684)

doi:10.1002/smll.202501600

DOE OSTI · 2536763

Designing Advanced Electrolytes for High-Voltage High-Capacity Disordered Rocksalt Cathodes

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Abstract

Lithium (Li)-excess transition metal oxide materials which crystallize in the cation-disordered rock salt (DRX) structure are promising cathodes for realizing low-cost, high-energy-density Li batteries. However, the state-of-the-art electrolytes for Li-ion batteries cannot meet the high-voltage stability requirement for high-voltage DRX cathodes, thus new electrolytes are urgently demanded. It has been reported that the solvation structures and properties of the electrolytes critically influence the performance and stability of the batteries. In this study, the structure–property relationships of various electrolytes with different solvent-to-diluent ratios are systematically investigated through a combination of theoretical calculations and experimental tests and analyses. This approach guides the development of electrolytes with unique solvation structures and characteristics, exhibiting high voltage stability, and enhancing the formation of stable electrode/electrolyte interphases. These electrolytes enable the realization of Li||Li 1.094 Mn 0.676 Ti 0.228 O 2 (LMTO) DRX cells with improved performance compared to the conventional electrolyte. Specifically, Li||LMTO cells with the optimized advanced controlled-solvation electrolyte deliver higher specific capacity and longer cycle life compared to cells with the conventional electrolyte. Additionally, the investigation into the structure–property relationship provides a foundational basis for designing advanced electrolytes, which are crucial for the stable cycling of emerging high-voltage cathodes.

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25 ENERGY STORAGE cathode electrolyte interphase disordered rocksalt cathode electrolyte high voltage solid electrolyte interphase

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Ahmed, Ridwan A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000329186219), Mohanakrishnan, Rohith Srinivaas [University of California, Berkeley, CA (United States)], Wang, Jingyang [University of California, Berkeley, CA (United States)], Koirala, Krishna P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:000000029137917X), Zhao, Qian [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Environmental Molecular Sciences Laboratory (EMSL)] (ORCID:0000000344893691), Fu, Yanbao [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017752680X), Chen, Ying [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)], Rastinejad, Justin C. [University of California, Berkeley, CA (United States)], Li, Tianyu [University of California, Berkeley, CA (United States)], Zhong, Lirong [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:000000015052939X), Zuba, Mateusz [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000232097922), Siu, Carrie [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000225035408), Kahvecioglu, Ozgenur [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000239883301), Clément, Raphaële J. [Univ. of California, Santa Barbara, CA (United States)], McCloskey, Bryan D. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000165992336), Battaglia, Vincent S. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000255969148), Persson, Kristin [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000324955509), Wang, Chongmin [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Environmental Molecular Sciences Laboratory (EMSL)] (ORCID:0000000333270958), Xu, Wu [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)] (ORCID:0000000226858684). 2025-03-24. Designing Advanced Electrolytes for High-Voltage High-Capacity Disordered Rocksalt Cathodes. https://doi.org/10.1002/smll.202501600

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