Patel Sawankumar V, Lacivita Valentina, Liu Haoyu, Truong Erica, Jin Yongkang, Wang Eric, Miara Lincoln, Kim Ryounghee, Gwon Hyeokjo, Zhang Rongfu, Hung Ivan, Gan Zhehong, Jung Sung-Kyun, Hu Yan-Yan
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA.
Center of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
Sci Adv. 2023 Nov 24;9(47):eadj9930. doi: 10.1126/sciadv.adj9930. Epub 2023 Nov 22.
2LiX-GaF (X = Cl, Br, I) electrolytes offer favorable features for solid-state batteries: mechanical pliability and high conductivities. However, understanding the origin of fast ion transport in 2LiX-GaF has been challenging. The ionic conductivity order of 2LiCl-GaF (3.20 mS/cm) > 2LiBr-GaF (0.84 mS/cm) > 2LiI-GaF (0.03 mS/cm) contradicts binary LiCl (10 S/cm) < LiBr (10 S/cm) < LiI (10 S/cm). Using multinuclear Li, Ga, F solid-state nuclear magnetic resonance and density functional theory simulations, we found that Ga(F,X) polyanions boost Li-ion transport by weakening Li-X interactions via charge clustering. In 2LiBr-GaF and 2LiI-GaF, Ga-X coordination is reduced with decreased F participation, compared to 2LiCl-GaF. These insights will inform electrolyte design based on charge clustering, applicable to various ion conductors. This strategy could prove effective for producing highly conductive multivalent cation conductors such as Ca and Mg, as charge clustering of carboxylates in proteins is found to decrease their binding to Ca and Mg.
2LiX-GaF（X = Cl、Br、I）电解质为固态电池提供了有利特性：机械柔韧性和高电导率。然而，了解2LiX-GaF中快速离子传输的起源一直具有挑战性。2LiCl-GaF（3.20 mS/cm）> 2LiBr-GaF（0.84 mS/cm）> 2LiI-GaF（0.03 mS/cm）的离子电导率顺序与二元LiCl（10 S/cm）< LiBr（10 S/cm）< LiI（10 S/cm）相矛盾。通过多核Li、Ga、F固态核磁共振和密度泛函理论模拟，我们发现Ga(F,X)多阴离子通过电荷聚集削弱Li-X相互作用来促进锂离子传输。与2LiCl-GaF相比，在2LiBr-GaF和2LiI-GaF中，随着F参与度降低，Ga-X配位减少。这些见解将为基于电荷聚集的电解质设计提供信息，适用于各种离子导体。由于发现蛋白质中羧酸盐的电荷聚集会降低它们与Ca和Mg的结合，这种策略可能被证明对生产高导电性多价阳离子导体（如Ca和Mg）有效。
