LiCrS2 and LiMnS2 Cathodes with Extraordinary Mixed Electron-Ion Conductivities and Favorable Interfacial Compatibilities with Sulfide Electrolyte
LiCrS2 and LiMnS2 Cathodes with Extraordinary Mixed Electron-Ion Conductivities and Favorable Interfacial Compatibilities with Sulfide Electrolyte
复制标题
LiCrS2 和 LiMnS2 阴极具有出色的混合电子-离子电导率以及与硫化物电解质良好的界面相容性
DOI：
10.1021/acsami.8b12026
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发表时间：
2018
影响因子：
9.5
通讯作者：
Zhu Hong
中科院分区：
文献类型：
--
作者：
Xu Zhen Ming;Bo Shou Hang;Zhu Hong
用于全固态锂离子电池的硫化物型固态电解质越来越受到人们的关注。然而，氧和硫元素之间的电负性差异使得硫化物型固态电解质与常规LiCoO 2阴极化学不相容。在这项工作中，我们提出了一系列黄铜矿结构的硫化物型材料，并通过第一性原理计算系统地评估了它们作为全固态锂离子电池正极材料的性能。所有五种金属LiMS 2（M = Cr、Mn、Fe、Co和Ni）材料都是超离子导体，具有在43至99 meV范围内的极小的锂离子迁移势垒，远低于大多数氧化物甚至硫化物型阴极。电压和体积计算表明，只有LiCrS 2和LiMnS 2阴极在循环过程中是结构稳定的，稳定的电压平台在0.3V，远高于P3 m1-LiTiS 2阴极。首次从电极/固体电解质界面电荷转移和再分布的新角度研究了界面锂输运电阻。LiCrS 2和LiMnS 2阴极与Li 3 PS4电解液具有良好的界面相容性。研究表明，金属LiCrS 2和LiMnS 2超离子导体在全固态锂离子电池中具有优异的倍率性能、高的能量密度、良好的结构稳定性以及与电解液Li 3 PS4良好的界面相容性。
Sulfide-type solid-state electrolytes for all-solid-state lithium ion batteries are capturing more and more attention. However, the electronegativity difference between the oxygen and the sulfur element makes sulfide-type solid-state electrolytes chemically incompatible with the conventional LiCoO2cathode. In this work, we proposed a series of chalcopyrite-structured sulfide-type materials and systematically assessed their performances as the cathode materials in all-solid-state lithium ion batteries by first-principle calculations. All the five metallic LiMS2(M = Cr, Mn, Fe, Co, and Ni) materials are superionic conductors with extremely small lithium ion migration barriers in the range from 43 to 99 meV, much lower than most oxide- and even sulfide-type cathodes. Voltage and volume calculations indicate that only LiCrS2and LiMnS2cathodes are structurally stable during cycling with the stable voltage plateaus at ∼3 V, much higher than that of theP3m1-LiTiS2cathode. For the first time, we studied the interfacial lithium transport resistance from a new perspective of charge transfer and redistribution at the electrode/solid-state electrolyte interface. LiCrS2and LiMnS2cathodes exhibit favorable interfacial compatibilities with Li3PS4electrolyte. Our investigations demonstrate that the metallic LiCrS2and LiMnS2superionic conductors would possess excellent rate capability, high energy density, good structural stability during cycling, and favorable interfacial compatibility with Li3PS4electrolyte in all-solid-state lithium ion batteries.